About Journal
Vol.42, No.19
September 2021
Semimonthly
ISSN 1002-0306
CN 11-1759/TS
- JournalOnline
- AcceptedManuscript
- Current Issue
- Archive
- Top View
Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
, Available online ,
doi: 10.13386/j.issn1002-0306.2021030026
Abstract:
, Available online ,
doi: 10.13386/j.issn1002-0306.2020010222
Abstract:
, Available online ,
doi: 10.13386/j.issn1002-0306.2020100019
Abstract:
, Available online ,
doi: 10.13386/j.issn1002-0306.2020100118
Abstract:
, Available online ,
doi: 10.13386/j.issn1002-0306.2020100030
Abstract:
Display Method:
2021, 42(19): 1-7.
doi: 10.13386/j.issn1002-0306.2021030247
Abstract:
Biospeckle laser technique is a spectroscopy technology that uses He-Ne laser to irradiate the surface of the sample, forming different speckle patterns due to the different light scattering capabilities of the sample, so as to realize the qualitative and quantitative analysis of sample quality and nutrients. The size of the biologic activity is related to the physical characteristics, chemical composition and internal quality of the sample during the biochemical reaction. This technique has the advantages of small damage to samples, short detection time, and can be applied to the aging detection, freshness detection and quality detection of agricultural and livestock products, but its poor stability and shallow penetration depth also limit its application. This article briefly describes the characteristics of biospeckle laser technique, focusing on its non-destructive detection principles and the research progress of its application effects in food aging, freshness, and quality detection, and prospects its application potential and limitations in food detection. It aims to provide theoretical and technical support for the application of this technique in the field of food non-destructive detection.
Biospeckle laser technique is a spectroscopy technology that uses He-Ne laser to irradiate the surface of the sample, forming different speckle patterns due to the different light scattering capabilities of the sample, so as to realize the qualitative and quantitative analysis of sample quality and nutrients. The size of the biologic activity is related to the physical characteristics, chemical composition and internal quality of the sample during the biochemical reaction. This technique has the advantages of small damage to samples, short detection time, and can be applied to the aging detection, freshness detection and quality detection of agricultural and livestock products, but its poor stability and shallow penetration depth also limit its application. This article briefly describes the characteristics of biospeckle laser technique, focusing on its non-destructive detection principles and the research progress of its application effects in food aging, freshness, and quality detection, and prospects its application potential and limitations in food detection. It aims to provide theoretical and technical support for the application of this technique in the field of food non-destructive detection.
More+
2021, 42(19): 8-14.
doi: 10.13386/j.issn1002-0306.2019080180
Abstract:
In order to study the interaction between Latifoloside G, Latifoloside C and Kudinoside G and bovine serum albumin (BSA) at different temperatures, and to provide experimental basis for the study of the transport and mechanism of Latifoloside in vivo, this paper used fluorescence spectroscopy to study the binding mechanism, binding mode, binding constants and binding sites of small molecules and proteins, and used circular dichroism to study the conformational changes of proteins. The results showed that all three saponins can effectively quench the endogenous fluorescence of BSA. Kudinoside G was static quenching, andLatifoloside G and Latifoloside C were dynamic quenching. With the increased of the concentration of the three small molecules, the endogenous fluorescence intensity of BSA decreases and the maximum emission peak of BSA was slightly blue-shifted (from 347 nm to 345 nm) at both temperatures, and the order of the binding ability of three saponins to BSA could be determined as Latifoloside G>Latifoloside C>Kudinoside G. The main types of forces between Kudinoside G and BSA were hydrogen bonding and Van der Waals forces, and the main forces between Latifoloside G and Latifoloside C and BSA were hydrophobic. The binding capacity of Latifoloside G and Kudinoside G with BSA was related to the polar group connected to C-28, and then Latifoloside C of alkane type was easier to insert into the hydrophobic cavity of BSA than Kudinoside G. The circular dichroism spectrum showed that the combination of three saponins with BSA could change the internal structural environment of BSA, the α-helix content increases, the microenvironment polarity decreases, and the hydrophobicity increased.
In order to study the interaction between Latifoloside G, Latifoloside C and Kudinoside G and bovine serum albumin (BSA) at different temperatures, and to provide experimental basis for the study of the transport and mechanism of Latifoloside in vivo, this paper used fluorescence spectroscopy to study the binding mechanism, binding mode, binding constants and binding sites of small molecules and proteins, and used circular dichroism to study the conformational changes of proteins. The results showed that all three saponins can effectively quench the endogenous fluorescence of BSA. Kudinoside G was static quenching, andLatifoloside G and Latifoloside C were dynamic quenching. With the increased of the concentration of the three small molecules, the endogenous fluorescence intensity of BSA decreases and the maximum emission peak of BSA was slightly blue-shifted (from 347 nm to 345 nm) at both temperatures, and the order of the binding ability of three saponins to BSA could be determined as Latifoloside G>Latifoloside C>Kudinoside G. The main types of forces between Kudinoside G and BSA were hydrogen bonding and Van der Waals forces, and the main forces between Latifoloside G and Latifoloside C and BSA were hydrophobic. The binding capacity of Latifoloside G and Kudinoside G with BSA was related to the polar group connected to C-28, and then Latifoloside C of alkane type was easier to insert into the hydrophobic cavity of BSA than Kudinoside G. The circular dichroism spectrum showed that the combination of three saponins with BSA could change the internal structural environment of BSA, the α-helix content increases, the microenvironment polarity decreases, and the hydrophobicity increased.
2021, 42(19): 15-20.
doi: 10.13386/j.issn1002-0306.2020090324
Abstract:
Objective: To improve the water solubility of Kudinoside D. Methods: Using atmospheric column chromatography, semi-preparative high performance liquid chromatography and other means to separate and purify saponins from Ilex kudingcha C.J.Tseng, the compound Kudinoside D was obtained. Using polyglutamic acid (γ-PGA) and L-phenylalanine ethyl ester (L-PAE) as raw materials, Kudinoside D nanoparticles were prepared by precipitation method and dialysis method respectively. The physical and chemical properties of nanoparticles were characterized by transmission electron microscopy and dynamic nanoparticle size analyzer, and their in vitro drug release characteristics were investigated by dialysis. Results: Compared with the precipitation method, the encapsulation efficiency and drug loading of Kudinoside D nanoparticles prepared by the dialysis method were increased by 1.5 and 4.5 times, respectively, the encapsulation rate reached 65.46%, and the drug loading reached 13.24%. Kudinoside D nanoparticles had a regular spherical shape with an average particle size of (75±25) nm and a Zeta potential of 33.7. Conclusion: In vitro drug release experiments show that Kudinoside D nanoparticles can significantly improve the water solubility of the drug and have a good sustained release effect in vitro.
Objective: To improve the water solubility of Kudinoside D. Methods: Using atmospheric column chromatography, semi-preparative high performance liquid chromatography and other means to separate and purify saponins from Ilex kudingcha C.J.Tseng, the compound Kudinoside D was obtained. Using polyglutamic acid (γ-PGA) and L-phenylalanine ethyl ester (L-PAE) as raw materials, Kudinoside D nanoparticles were prepared by precipitation method and dialysis method respectively. The physical and chemical properties of nanoparticles were characterized by transmission electron microscopy and dynamic nanoparticle size analyzer, and their in vitro drug release characteristics were investigated by dialysis. Results: Compared with the precipitation method, the encapsulation efficiency and drug loading of Kudinoside D nanoparticles prepared by the dialysis method were increased by 1.5 and 4.5 times, respectively, the encapsulation rate reached 65.46%, and the drug loading reached 13.24%. Kudinoside D nanoparticles had a regular spherical shape with an average particle size of (75±25) nm and a Zeta potential of 33.7. Conclusion: In vitro drug release experiments show that Kudinoside D nanoparticles can significantly improve the water solubility of the drug and have a good sustained release effect in vitro.
2021, 42(19): 21-28.
doi: 10.13386/j.issn1002-0306.2020120148
Abstract:
The purpose of this study was to investigate the effects of repeated freeze-thaw phenomenon on on water holding capacity, myofibrillar protein oxidation and dissolution characteristics of Tibetan mutton during chilled storage. Tibetan mutton was as the research objects and after repeated freezing-thawing for 0, 1, 3 and 5 times, the mutton was refrigerated at 4 ℃ for 1, 3, 5 and 7 days. And then the water holding capacity, myofibril oxidation characteristics, protein solubility and muscle fiber microstructure were determined. The results showed that compared with T3 group, the thawing loss rate of T5 group was significantly increased by 63.08%, 43.20%, 20.58% and 16.20%, and compared with T0 group, the drip loss rate of T5 group was significantly increased by 29.16%, 21.09%, 22.16% and 25.47%, respectively and the pressure loss rate significantly increased by 23.76%, 20.45%, 21.17% and 20.15% (P<0.05) during chilled storage. The carbonyl content and surface hydrophobicity all presented a significant increase and total sulfhydryl content presented a significant decrease (P<0.05), meanwhile, with the increase of freezing-thawing cycles the protein solubility decreased significantly as well as the damage degree of muscle fiber microstructure increased gradually. The correlation results showed that freezing-thawing cycles times were significantly correlated with the degree of protein oxidation and protein solubility (P<0.01), and the water holding capacity also had significant correlation with the above indexes (P<0.01). The above results indicated that the more times of freezing-thawing cycle, the more serious oxidative degree of myofibril protein, the more serious damage to muscle fiber microstructure, and the lower protein solubility, which was therefore not conducive to the maintenance of meat water holding capacity. At the same time, the refrigeration process also had adverse effects on water holding capacity, myofibril oxidation, protein solubility and muscle fiber microstructure. Therefore, the control of temperature fluctuation during meat storage, transportation and production is of great significance to maintain meat quality.
The purpose of this study was to investigate the effects of repeated freeze-thaw phenomenon on on water holding capacity, myofibrillar protein oxidation and dissolution characteristics of Tibetan mutton during chilled storage. Tibetan mutton was as the research objects and after repeated freezing-thawing for 0, 1, 3 and 5 times, the mutton was refrigerated at 4 ℃ for 1, 3, 5 and 7 days. And then the water holding capacity, myofibril oxidation characteristics, protein solubility and muscle fiber microstructure were determined. The results showed that compared with T3 group, the thawing loss rate of T5 group was significantly increased by 63.08%, 43.20%, 20.58% and 16.20%, and compared with T0 group, the drip loss rate of T5 group was significantly increased by 29.16%, 21.09%, 22.16% and 25.47%, respectively and the pressure loss rate significantly increased by 23.76%, 20.45%, 21.17% and 20.15% (P<0.05) during chilled storage. The carbonyl content and surface hydrophobicity all presented a significant increase and total sulfhydryl content presented a significant decrease (P<0.05), meanwhile, with the increase of freezing-thawing cycles the protein solubility decreased significantly as well as the damage degree of muscle fiber microstructure increased gradually. The correlation results showed that freezing-thawing cycles times were significantly correlated with the degree of protein oxidation and protein solubility (P<0.01), and the water holding capacity also had significant correlation with the above indexes (P<0.01). The above results indicated that the more times of freezing-thawing cycle, the more serious oxidative degree of myofibril protein, the more serious damage to muscle fiber microstructure, and the lower protein solubility, which was therefore not conducive to the maintenance of meat water holding capacity. At the same time, the refrigeration process also had adverse effects on water holding capacity, myofibril oxidation, protein solubility and muscle fiber microstructure. Therefore, the control of temperature fluctuation during meat storage, transportation and production is of great significance to maintain meat quality.
2021, 42(19): 29-35.
doi: 10.13386/j.issn1002-0306.2020120156
Abstract:
To explore the effect of different ratio of light on physiological reaction and main amino acid accumulation of annual Fuding-dabaicha leaves. The L1 (red light accounted for 71.8%), L2 (blue light accounted for 62.7%), L3 (red 43.1%, blue 29%, green accounted for 27.9%) and L0 (green light accounted for 82.1%) were set in artificial climate boxes with 100 μmol·m−2·s−1 photosynthetic photon flux density and 12 h photo period. The leaf growth index were determined by nitrogen balance index instrument and the theanin, glutamate and aspartate contents were determined by an automatic amino acid analyzer. The results showed that with the increase of treatment time, the chlorophyll index and nitrogen balance index of tea leaves were significantly increased by all light treatments. Compared with L0, L1 significantly increased the nitrogen balance index of tea leaves (P<0.05), followed by L3, index of flavonoids and polyphenols content between different light treatment had no significant difference. Compared with L0, the content of theanine, glutamate and aspartate under L3 and L2 treatments increased significantly. In conclusion, L3 (an equilibrium ratio of red, blue and green light) can be considered as a suitable artificalight source for tea leaves growth and to ensure the maximun retention of main amino acid.
To explore the effect of different ratio of light on physiological reaction and main amino acid accumulation of annual Fuding-dabaicha leaves. The L1 (red light accounted for 71.8%), L2 (blue light accounted for 62.7%), L3 (red 43.1%, blue 29%, green accounted for 27.9%) and L0 (green light accounted for 82.1%) were set in artificial climate boxes with 100 μmol·m−2·s−1 photosynthetic photon flux density and 12 h photo period. The leaf growth index were determined by nitrogen balance index instrument and the theanin, glutamate and aspartate contents were determined by an automatic amino acid analyzer. The results showed that with the increase of treatment time, the chlorophyll index and nitrogen balance index of tea leaves were significantly increased by all light treatments. Compared with L0, L1 significantly increased the nitrogen balance index of tea leaves (P<0.05), followed by L3, index of flavonoids and polyphenols content between different light treatment had no significant difference. Compared with L0, the content of theanine, glutamate and aspartate under L3 and L2 treatments increased significantly. In conclusion, L3 (an equilibrium ratio of red, blue and green light) can be considered as a suitable artificalight source for tea leaves growth and to ensure the maximun retention of main amino acid.
2021, 42(19): 36-42.
doi: 10.13386/j.issn1002-0306.2020120233
Abstract:
In order to investigate the changes of protein and lipid oxidation and flavor substances of mutton during cold storage, mutton was stored at 4 ℃ and relative humidity 48%, and packaged with ordinary PE plastic wrap, determination of different cold storage time of mutton thiobarbituric acid reactive substances (TBARS) value, sulfhydryl content and the change of volatile flavoring substances. Results showed that during refrigeration storage, the value of TBARS increased first, then decreased and then increased. The sulfhydryl value decreased on the four days ago and increased from the 5th day. Nine kinds of volatile components were detected from the refrigeration mutton, a total of 31 kinds of volatile compounds, the content of 1-butanolwith a smell of camphor was reduced with the storage time. The main flavoring substances of heptanal, octanal and hexanal were the highest levels on the third day, the 3-hydroxy-2-butanone and 2-heptanone were detected on the 5th day. 3-methylbutanal and dimethyl disulfide were detected which caused sour and rancid smell, on the 7th day. In conclusion, the flavor quality of mutton on the 3th day is better under refrigeration storage conditions, and the turning point of mutton deterioration may be on the 5th day.
In order to investigate the changes of protein and lipid oxidation and flavor substances of mutton during cold storage, mutton was stored at 4 ℃ and relative humidity 48%, and packaged with ordinary PE plastic wrap, determination of different cold storage time of mutton thiobarbituric acid reactive substances (TBARS) value, sulfhydryl content and the change of volatile flavoring substances. Results showed that during refrigeration storage, the value of TBARS increased first, then decreased and then increased. The sulfhydryl value decreased on the four days ago and increased from the 5th day. Nine kinds of volatile components were detected from the refrigeration mutton, a total of 31 kinds of volatile compounds, the content of 1-butanolwith a smell of camphor was reduced with the storage time. The main flavoring substances of heptanal, octanal and hexanal were the highest levels on the third day, the 3-hydroxy-2-butanone and 2-heptanone were detected on the 5th day. 3-methylbutanal and dimethyl disulfide were detected which caused sour and rancid smell, on the 7th day. In conclusion, the flavor quality of mutton on the 3th day is better under refrigeration storage conditions, and the turning point of mutton deterioration may be on the 5th day.
2021, 42(19): 43-55.
doi: 10.13386/j.issn1002-0306.2020120282
Abstract:
In this paper, the differences in physical and chemical index, nutrients and volatile aroma compounds of 24 brown sugar (Traditional brown sugar (Tbs), Processed brown sugar (Pbs), Mechanism brown sugar (Mbs)) samples processed by different methods were analyzed and compared. The results showed that colors of 24 brown sugar samples were mainly brown composed of red and yellow, and the color of Mbs and Pbs was darker brown, while the color of Tbs was brownish yellow. Sucrose and reducing sugar were the main components of brown sugar, and the sucrose content of Tbs was lower than that of Mbs and Pbs, while the reducing sugar was the opposite. The ash content of Pbs and Mbs was 3.55% and 4.09%, respectively, and the ash content of Tbs was 2.26%. The protein and polyphenol contents of Pbs and Mbs were slightly higher than those of Tbs. The average carbohydrate and energy of Tbs were 92.94% and 1598.67 kJ, respectively, which were higher than those of Mbs and Pbs. There was little difference in fat content of brown sugars among the three processing methods. Brown sugar was rich in minerals and amino acids. Among brown sugar samples processed by different methods, K content was the highest, followed by Ca and P. Among the trace elements, the content of Fe was the most and the content of Se was the least, and the contents of Cu, Si and Zn have little difference among different processing methods. Seventeen kinds of amino acids were identified in Tbs, Mbs and Pbs, among which aspartic acid and glutamic acid were the main amino acids. A total of 104 volatile aroma compounds were detected in 9 kinds of brown sugar processed by different methods, among which acids, alcohols and pyrazines were the most.
In this paper, the differences in physical and chemical index, nutrients and volatile aroma compounds of 24 brown sugar (Traditional brown sugar (Tbs), Processed brown sugar (Pbs), Mechanism brown sugar (Mbs)) samples processed by different methods were analyzed and compared. The results showed that colors of 24 brown sugar samples were mainly brown composed of red and yellow, and the color of Mbs and Pbs was darker brown, while the color of Tbs was brownish yellow. Sucrose and reducing sugar were the main components of brown sugar, and the sucrose content of Tbs was lower than that of Mbs and Pbs, while the reducing sugar was the opposite. The ash content of Pbs and Mbs was 3.55% and 4.09%, respectively, and the ash content of Tbs was 2.26%. The protein and polyphenol contents of Pbs and Mbs were slightly higher than those of Tbs. The average carbohydrate and energy of Tbs were 92.94% and 1598.67 kJ, respectively, which were higher than those of Mbs and Pbs. There was little difference in fat content of brown sugars among the three processing methods. Brown sugar was rich in minerals and amino acids. Among brown sugar samples processed by different methods, K content was the highest, followed by Ca and P. Among the trace elements, the content of Fe was the most and the content of Se was the least, and the contents of Cu, Si and Zn have little difference among different processing methods. Seventeen kinds of amino acids were identified in Tbs, Mbs and Pbs, among which aspartic acid and glutamic acid were the main amino acids. A total of 104 volatile aroma compounds were detected in 9 kinds of brown sugar processed by different methods, among which acids, alcohols and pyrazines were the most.
2021, 42(19): 56-63.
doi: 10.13386/j.issn1002-0306.2020120284
Abstract:
Objective: The antioxidant and hypoglycemic effects in vitro of the extract from Blechnum orientale L. were compared. Methods: By using Folin-Ciocalteu method, the total polyphenol content of extracts were determined. The content of flavonoids was determined by NaNO2-Al(NO3)3 method. In addition, radicals scavenging (DPPH·, ABTS+·), reducing ability, α-glucosidase and α-amylase inhibitory were carry out to evaluate their antioxidant and hypoglycemic activities. Pearson correlation analysis method was used to measure the correlation of component content and activities. Results: The results showed that there were significant differences in the content of total phenolic and flavonoids, antioxidant activity and α-glucosidase inhibitory activity among different processing products of ethanol extracts from Blechnum orientale L. The alcohol extract from fresh product had the highest content of total phenols ((593±3.45) mg GA/g) and total flavonoids ((156.75±1.28) mg RT/g), and the fresh product showed the strongest iron ion reduction ability, ABTS free radical scavenging ability and DPPH free radical scavenging ability. The alcohol extract from wet product had the strongest inhibitory effect on α-glucosidase and α-amylase. The contents of total phenols and flavonoids in Blechnum orientale L. with different processing methods were significantly positively correlated with their antioxidant (P<0.01) and were significant positive correlated with their hypoglycemic activity (P<0.05). Conclusion: The alcohol extract from fresh product had the highest antioxidant activity and wet product had the strongest hypoglycemic activity in vitro. The active ingredient may be total phenolic and flavonoids.
Objective: The antioxidant and hypoglycemic effects in vitro of the extract from Blechnum orientale L. were compared. Methods: By using Folin-Ciocalteu method, the total polyphenol content of extracts were determined. The content of flavonoids was determined by NaNO2-Al(NO3)3 method. In addition, radicals scavenging (DPPH·, ABTS+·), reducing ability, α-glucosidase and α-amylase inhibitory were carry out to evaluate their antioxidant and hypoglycemic activities. Pearson correlation analysis method was used to measure the correlation of component content and activities. Results: The results showed that there were significant differences in the content of total phenolic and flavonoids, antioxidant activity and α-glucosidase inhibitory activity among different processing products of ethanol extracts from Blechnum orientale L. The alcohol extract from fresh product had the highest content of total phenols ((593±3.45) mg GA/g) and total flavonoids ((156.75±1.28) mg RT/g), and the fresh product showed the strongest iron ion reduction ability, ABTS free radical scavenging ability and DPPH free radical scavenging ability. The alcohol extract from wet product had the strongest inhibitory effect on α-glucosidase and α-amylase. The contents of total phenols and flavonoids in Blechnum orientale L. with different processing methods were significantly positively correlated with their antioxidant (P<0.01) and were significant positive correlated with their hypoglycemic activity (P<0.05). Conclusion: The alcohol extract from fresh product had the highest antioxidant activity and wet product had the strongest hypoglycemic activity in vitro. The active ingredient may be total phenolic and flavonoids.
2021, 42(19): 64-69.
doi: 10.13386/j.issn1002-0306.2021010197
Abstract:
In this paper, silver carp and cod were used as raw materials to make mixed surimi. Five heating methods (water bath two stage heating, microwave heating, water bath microwave combination, steam heating, high pressure ripening) were used to heat the mixed surimi. By SDS-PAGE gel electrophoresis and scanning electron microscopy, the effects of different heating methods on the gel properties of mixed surimi gel were studied. The results showed that different heating methods had different effects on the characteristics of mixed surimi gel. The strength of mixed surimi gel was 2979.47 g·cm compared with that of traditional water bath two-stage heating, microwave heating, steam heating and high pressure curing method, water bath microwave combined method was 94.33%, whiteness was 83.75, hardness, elasticity and chewiness were significantly improved (P<0.05). Scanning electron microscopy (SEM) showed that the three-dimensional network structure of surimi gel prepared by microwave coupling in water bath was tight, the pores of the gel were small and the surface was smooth. Combined with SDS-PAGE gel electrophoresis analysis, heating can affect the degradation of protein components in mixed surimi gel, while the main protein components of mixed surimi gel obtained by microwave coupling in water bath remain more.
In this paper, silver carp and cod were used as raw materials to make mixed surimi. Five heating methods (water bath two stage heating, microwave heating, water bath microwave combination, steam heating, high pressure ripening) were used to heat the mixed surimi. By SDS-PAGE gel electrophoresis and scanning electron microscopy, the effects of different heating methods on the gel properties of mixed surimi gel were studied. The results showed that different heating methods had different effects on the characteristics of mixed surimi gel. The strength of mixed surimi gel was 2979.47 g·cm compared with that of traditional water bath two-stage heating, microwave heating, steam heating and high pressure curing method, water bath microwave combined method was 94.33%, whiteness was 83.75, hardness, elasticity and chewiness were significantly improved (P<0.05). Scanning electron microscopy (SEM) showed that the three-dimensional network structure of surimi gel prepared by microwave coupling in water bath was tight, the pores of the gel were small and the surface was smooth. Combined with SDS-PAGE gel electrophoresis analysis, heating can affect the degradation of protein components in mixed surimi gel, while the main protein components of mixed surimi gel obtained by microwave coupling in water bath remain more.
2021, 42(19): 70-77.
doi: 10.13386/j.issn1002-0306.2021010205
Abstract:
Using purple brown rice as raw material, extruded purple brown rice flour was prepared by twin-screw extrusion technology, the changes of nutrition, hydration properties, gelatinization properties, thermal properties and rheological properties of purple brown rice flour before and after extrusion were analyzed. The results showed that , compared with the raw materials, the total starch, amylopectin and fat content of the extruded purple brown rice flour decreased by 12.45%, 16.03%, and 67.45% respectively, the protein, total amino acid, calcium and zinc content changes were not change significantly (P>0.05). Besides, the content of total phenols, total flavonoids and total anthocyanins were reduced by 23.70%, 28.34% and 29.16% respectively, and the antioxidant activity was weakened. The water solubility index and water absorption index were increased by 2.80, 1.07 times respectively, and the color became deeper. Under the same shear rate, the extruded flour has lower shear stress, which easier to stir. The results of RVA and DSC showed that the peak viscosity, lowest viscosity, attenuation value, final viscosity and retrogradation value of extruded purple brown rice flour decreased by 3528.50, 2038.83, 1489.00, 3975.33, 1937.00 cP, the gelatinization degree was 93.15%, and the enthalpy reduced from 5.23 J/g to 0.74 J/g, indicating that most of the starch has been gelatinized. According to this, the nutritive value retention of the extruded purple brown rice flour was still at a relatively high level, the hydration capacity was significantly improved, the taste was good, and it had good application value.
Using purple brown rice as raw material, extruded purple brown rice flour was prepared by twin-screw extrusion technology, the changes of nutrition, hydration properties, gelatinization properties, thermal properties and rheological properties of purple brown rice flour before and after extrusion were analyzed. The results showed that , compared with the raw materials, the total starch, amylopectin and fat content of the extruded purple brown rice flour decreased by 12.45%, 16.03%, and 67.45% respectively, the protein, total amino acid, calcium and zinc content changes were not change significantly (P>0.05). Besides, the content of total phenols, total flavonoids and total anthocyanins were reduced by 23.70%, 28.34% and 29.16% respectively, and the antioxidant activity was weakened. The water solubility index and water absorption index were increased by 2.80, 1.07 times respectively, and the color became deeper. Under the same shear rate, the extruded flour has lower shear stress, which easier to stir. The results of RVA and DSC showed that the peak viscosity, lowest viscosity, attenuation value, final viscosity and retrogradation value of extruded purple brown rice flour decreased by 3528.50, 2038.83, 1489.00, 3975.33, 1937.00 cP, the gelatinization degree was 93.15%, and the enthalpy reduced from 5.23 J/g to 0.74 J/g, indicating that most of the starch has been gelatinized. According to this, the nutritive value retention of the extruded purple brown rice flour was still at a relatively high level, the hydration capacity was significantly improved, the taste was good, and it had good application value.
2021, 42(19): 78-83.
doi: 10.13386/j.issn1002-0306.2021010208
Abstract:
In order to solve the problem of poor hydrophobicity of anthocyanins, in this paper, the blueberry anthocyanin was acylated with ferulic acid and caffeic acid, and the structure, hydrophobicity and antioxidant activity of related products were analysed. The FTIR and UV-Vis analysis indicated that ferulic acid and caffeic acid were grafted on the -OH of the glycosyl of the blueberry anthocyanins through acylation reaction, and the acylation degree of the anthocyanins acylated with ferulic acid (Fe-An) and caffeic acid (Ca-An) was 3.65% and 3.71%, respectively. Meanwhile, the total anthocyanidin content was decreased from 370.2 mg/g (Na-An) to 219.2 mg/g (Fe-An) and 222.18 mg/g (Ca-An), respectively. In addition, the hydrophobicity and antioxidant activity of blueberry anthocyanins were significantly improved after acylation with the two phenolic acids. The octanol-water partition coefficient (KOW) was increased from −0.20 (Na-An) to 0.66 (Fe-An) and 0.78 (Ca-An), DPPH clearance increased from 66.3% (Na-An) to 68.4% (Fe-An) and 74.7% (Ca-An), and inhibition ratio of β-carotene bleaching increased from 63.1% (Na - An) to 85.5% (Fe-An) and 90.3% (Ca-An). The results show that the introduction of ferulic acid and caffeic acid significantly improve the hydrophobicity and antioxidant activity of blueberry anthocyanins, which will greatly expand the application of anthocyanins in high-fat foods.
In order to solve the problem of poor hydrophobicity of anthocyanins, in this paper, the blueberry anthocyanin was acylated with ferulic acid and caffeic acid, and the structure, hydrophobicity and antioxidant activity of related products were analysed. The FTIR and UV-Vis analysis indicated that ferulic acid and caffeic acid were grafted on the -OH of the glycosyl of the blueberry anthocyanins through acylation reaction, and the acylation degree of the anthocyanins acylated with ferulic acid (Fe-An) and caffeic acid (Ca-An) was 3.65% and 3.71%, respectively. Meanwhile, the total anthocyanidin content was decreased from 370.2 mg/g (Na-An) to 219.2 mg/g (Fe-An) and 222.18 mg/g (Ca-An), respectively. In addition, the hydrophobicity and antioxidant activity of blueberry anthocyanins were significantly improved after acylation with the two phenolic acids. The octanol-water partition coefficient (KOW) was increased from −0.20 (Na-An) to 0.66 (Fe-An) and 0.78 (Ca-An), DPPH clearance increased from 66.3% (Na-An) to 68.4% (Fe-An) and 74.7% (Ca-An), and inhibition ratio of β-carotene bleaching increased from 63.1% (Na - An) to 85.5% (Fe-An) and 90.3% (Ca-An). The results show that the introduction of ferulic acid and caffeic acid significantly improve the hydrophobicity and antioxidant activity of blueberry anthocyanins, which will greatly expand the application of anthocyanins in high-fat foods.
2021, 42(19): 84-91.
doi: 10.13386/j.issn1002-0306.2021010256
Abstract:
In this paper, the polysaccharides from the body wall of Urechis unicinctus was extracted by pepsin, and the composition of the extracted polysaccharides were analyzed. The adsorption of polysaccharides on MCM-41 was studied by the adsorption kinetics, adsorption thermodynamics. The results of composition analysis showed that the content of the total sugar was (78.82%±1.4%), the content of total protein was (10.5%±1.07%), and the content of sulfate radical was (0.52%±0.06%). The monosaccharide mainly contained glucose, mannose, galactose and xylose. The results of infrared spectrum analysis showed that the polysaccharide contained characteristic groups such as O-H, C-O-C, C=O, S=O, which indicated that there were uronic acid in the polysaccharide, and there was substitution of sulfate group. The mesoporous material MCM-41, with the average pore diameter 3.85 nm and the pore volume 1.25 cm3/g, was used to enrich the polysaccharide. It was found that the adsorption kinetics of the polysaccharide on MCM-41 conformed to the pseudo second order adsorption kinetics (PSO) model, in which the external diffusion and intra particle diffusion controlled the adsorption process. The adsorption thermodynamics of the polysaccharide on MCM-41 was consistent with both the Langmuir model and Freundlich model, indicating that the adsorption process of MCM-41 was mainly monolayer and accompanied by the adsorption of multi-layer. It was found that 10% SDS had stronger elution ability, which was caused by the destruction of hydrogen bond interaction between polysaccharide and water. The study on the adsorption mechanism of polysaccharides from the Urechis unicinctus on mesoporous material MCM-41 is expected to provide theoretical guidance for the enrichment and separation of polysaccharides, oligosaccharides, glycoproteins and glycopeptides in food industry.
In this paper, the polysaccharides from the body wall of Urechis unicinctus was extracted by pepsin, and the composition of the extracted polysaccharides were analyzed. The adsorption of polysaccharides on MCM-41 was studied by the adsorption kinetics, adsorption thermodynamics. The results of composition analysis showed that the content of the total sugar was (78.82%±1.4%), the content of total protein was (10.5%±1.07%), and the content of sulfate radical was (0.52%±0.06%). The monosaccharide mainly contained glucose, mannose, galactose and xylose. The results of infrared spectrum analysis showed that the polysaccharide contained characteristic groups such as O-H, C-O-C, C=O, S=O, which indicated that there were uronic acid in the polysaccharide, and there was substitution of sulfate group. The mesoporous material MCM-41, with the average pore diameter 3.85 nm and the pore volume 1.25 cm3/g, was used to enrich the polysaccharide. It was found that the adsorption kinetics of the polysaccharide on MCM-41 conformed to the pseudo second order adsorption kinetics (PSO) model, in which the external diffusion and intra particle diffusion controlled the adsorption process. The adsorption thermodynamics of the polysaccharide on MCM-41 was consistent with both the Langmuir model and Freundlich model, indicating that the adsorption process of MCM-41 was mainly monolayer and accompanied by the adsorption of multi-layer. It was found that 10% SDS had stronger elution ability, which was caused by the destruction of hydrogen bond interaction between polysaccharide and water. The study on the adsorption mechanism of polysaccharides from the Urechis unicinctus on mesoporous material MCM-41 is expected to provide theoretical guidance for the enrichment and separation of polysaccharides, oligosaccharides, glycoproteins and glycopeptides in food industry.
2021, 42(19): 92-96.
doi: 10.13386/j.issn1002-0306.2021020102
Abstract:
To improve the quality and drying rate of Diospyros lotus L. under the hot-air drying technology, the effects of constant temperature and staged cooling hot-air drying process on its drying characteristics, heat-sensitive nutrients, sensory quality and rehydration were compared. The technique of subsection temperature-changing than thermostatic shortened the drying time by 1/4, which significantly improved quality of finished products. The optimized conditions of the subsection temperature-changing hot air drying were as follows: preheated at (40±1) ℃ for 15 min, reduced moisture content to 41.0%±0.5%, 37.0%±0.5% and 35.0%±0.5% at (68±1), (63±1) and (55±1) ℃, respectively. The content of total sugar, total phenol and VC of dried Diospyros lotus L. were 49.53%±0.31%, (0.94±0.01) mg/g and (16.41±0.28) mg/100 g. The retention rate of nutrient substance were increased by 11.47%, 10.01% and 47.91%, respectively. Otherwise, drying rate increased to 18.75% and the sensory quality and re-hydration were better. Therefore, the product is easily accepted by consumers. The research results can provide theoretical basis and technical guidance for the industrial drying of Diospyros lotus L.
To improve the quality and drying rate of Diospyros lotus L. under the hot-air drying technology, the effects of constant temperature and staged cooling hot-air drying process on its drying characteristics, heat-sensitive nutrients, sensory quality and rehydration were compared. The technique of subsection temperature-changing than thermostatic shortened the drying time by 1/4, which significantly improved quality of finished products. The optimized conditions of the subsection temperature-changing hot air drying were as follows: preheated at (40±1) ℃ for 15 min, reduced moisture content to 41.0%±0.5%, 37.0%±0.5% and 35.0%±0.5% at (68±1), (63±1) and (55±1) ℃, respectively. The content of total sugar, total phenol and VC of dried Diospyros lotus L. were 49.53%±0.31%, (0.94±0.01) mg/g and (16.41±0.28) mg/100 g. The retention rate of nutrient substance were increased by 11.47%, 10.01% and 47.91%, respectively. Otherwise, drying rate increased to 18.75% and the sensory quality and re-hydration were better. Therefore, the product is easily accepted by consumers. The research results can provide theoretical basis and technical guidance for the industrial drying of Diospyros lotus L.
2021, 42(19): 97-105.
doi: 10.13386/j.issn1002-0306.2021030006
Abstract:
Objective: To study the 5α-Reductase (5α-R) inhibitory activity of Camellia oleifera (COLE) leaves extract, and to analyze the material basis of its extract with high 5α-R inhibitory activity. Method: Firstly, a 5α-R enzymatic reaction system was established, and the 5α-R activity was measured by high performance phase chromatography(HPLC). The extracts of Camellia oleifera leaves with different solvents were prepared, and the 5α-R inhibitory activity was measured and compared, with Dutasteride as the positive drug; 5α-R inhibition rate was used to select the best solvent of Camellia oleifera leaves extract; Folin-Ciocalteu method and sodium nitrite-aluminum nitrate-sodium hydroxide color method was used to determine the total phenol and total flavonoid content of each extract, and correlation between the 5α-R inhibition rate of each extract and the content of polyphenol and flavonoids was analyzed; ultra-high performance liquid chromatography tandem triple quadrupole time-of-flight mass spectrometry (UPLC-TRIPLE TOF-MS/MS) was used to analyze the chemical components of extract with the highest 5α-R inhibitory activity. Results: The enzymatic reaction system was determined as follows: 300 μL of phosphate buffer, 500 μL of 0.76 mg/mL enzyme extract, 50 μL of 2.0 mmol/L testosterone, 50 μL of sample, 2.0 mmol/L of NADPH 100 μL, reacted at 37 ℃ for 30 min. Different Camellia oleifera extracts had different levels of 5α-R inhibitory activity. The 50% ethanol extract of Camellia oleifera had the highest inhibition rate, reaching 49.77% ± 4.43%. Taking 5α-R inhibitory effect as an indicator, 50% ethanolwas the best extraction solvent. Pearson correlation analysis showed that the 5α-R inhibition rate of each Camellia oleifera extract was highly correlated with the content of total phenols and total flavonoids (r>0.6, r>0.8); UPLC-TRIPLE TOF-MS/MS analysis 22 kinds substances, five of which were reported that had the 5α-R inhibitory activity. Conclusion: The extract of Camellia oleifera leaves had 5α-R inhibitory activity and was a potential 5α-R inhibitor. Its inhibitory activity was related to the content of polyphenols and flavonoids. Quercetin, rutin, catechin, 3-O-galloyl-4, 6, -[(S)-hexahydroxybiphth-aloyl]-α/β-D-glucopyranose (Gemin D), 3, 4, 6-tri-O-galloyl-α/β-D-glucopyranose (GAG), might be the material basis for COLE to exert 5α-R inhibitory activity.
Objective: To study the 5α-Reductase (5α-R) inhibitory activity of Camellia oleifera (COLE) leaves extract, and to analyze the material basis of its extract with high 5α-R inhibitory activity. Method: Firstly, a 5α-R enzymatic reaction system was established, and the 5α-R activity was measured by high performance phase chromatography(HPLC). The extracts of Camellia oleifera leaves with different solvents were prepared, and the 5α-R inhibitory activity was measured and compared, with Dutasteride as the positive drug; 5α-R inhibition rate was used to select the best solvent of Camellia oleifera leaves extract; Folin-Ciocalteu method and sodium nitrite-aluminum nitrate-sodium hydroxide color method was used to determine the total phenol and total flavonoid content of each extract, and correlation between the 5α-R inhibition rate of each extract and the content of polyphenol and flavonoids was analyzed; ultra-high performance liquid chromatography tandem triple quadrupole time-of-flight mass spectrometry (UPLC-TRIPLE TOF-MS/MS) was used to analyze the chemical components of extract with the highest 5α-R inhibitory activity. Results: The enzymatic reaction system was determined as follows: 300 μL of phosphate buffer, 500 μL of 0.76 mg/mL enzyme extract, 50 μL of 2.0 mmol/L testosterone, 50 μL of sample, 2.0 mmol/L of NADPH 100 μL, reacted at 37 ℃ for 30 min. Different Camellia oleifera extracts had different levels of 5α-R inhibitory activity. The 50% ethanol extract of Camellia oleifera had the highest inhibition rate, reaching 49.77% ± 4.43%. Taking 5α-R inhibitory effect as an indicator, 50% ethanolwas the best extraction solvent. Pearson correlation analysis showed that the 5α-R inhibition rate of each Camellia oleifera extract was highly correlated with the content of total phenols and total flavonoids (r>0.6, r>0.8); UPLC-TRIPLE TOF-MS/MS analysis 22 kinds substances, five of which were reported that had the 5α-R inhibitory activity. Conclusion: The extract of Camellia oleifera leaves had 5α-R inhibitory activity and was a potential 5α-R inhibitor. Its inhibitory activity was related to the content of polyphenols and flavonoids. Quercetin, rutin, catechin, 3-O-galloyl-4, 6, -[(S)-hexahydroxybiphth-aloyl]-α/β-D-glucopyranose (Gemin D), 3, 4, 6-tri-O-galloyl-α/β-D-glucopyranose (GAG), might be the material basis for COLE to exert 5α-R inhibitory activity.
2021, 42(19): 106-117.
doi: 10.13386/j.issn1002-0306.2021030193
Abstract:
The volatile flavor compounds of five dominant aquatic raw materials (Litopenaeus vannamei, Procypris merus, Tilapia, Nemipterus virgatus and Pinctada martensii) in Guangxi were studied. They were analyzed by using electronic nose, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace-solid phase micro-extraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS) technology combined with sensory evaluation. The results showed that the fishy odors of the five aquatic raw materials was prominent. According to the analysis of electronic nose, inorganic sulfides, aromatic compounds (organic sulfides) and methyl compounds were the overall odors of the five aquatic raw materials. Among them, octanal, benzaldehyde (monomer), pentanal (monomer), 2-pentanone (monomer), 2-pinene, 2-butanone (monomer), butanal (dimer), ethyl propanoate, hexanal (monomer), benzaldehyde (dimer), heptanal (monomer) were considered to be the common compounds of the five aquatic raw materials. A total of 57 volatile compounds were identified by GC-MS. Alcohols, aldehydes and aromatic compounds were considered to be the main volatile compounds of five aquatic raw materials. 1-Octen-3-ol and nonanal were the key flavor compounds of five aquatic raw materials.
The volatile flavor compounds of five dominant aquatic raw materials (Litopenaeus vannamei, Procypris merus, Tilapia, Nemipterus virgatus and Pinctada martensii) in Guangxi were studied. They were analyzed by using electronic nose, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace-solid phase micro-extraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS) technology combined with sensory evaluation. The results showed that the fishy odors of the five aquatic raw materials was prominent. According to the analysis of electronic nose, inorganic sulfides, aromatic compounds (organic sulfides) and methyl compounds were the overall odors of the five aquatic raw materials. Among them, octanal, benzaldehyde (monomer), pentanal (monomer), 2-pentanone (monomer), 2-pinene, 2-butanone (monomer), butanal (dimer), ethyl propanoate, hexanal (monomer), benzaldehyde (dimer), heptanal (monomer) were considered to be the common compounds of the five aquatic raw materials. A total of 57 volatile compounds were identified by GC-MS. Alcohols, aldehydes and aromatic compounds were considered to be the main volatile compounds of five aquatic raw materials. 1-Octen-3-ol and nonanal were the key flavor compounds of five aquatic raw materials.
More+
2021, 42(19): 118-125.
doi: 10.13386/j.issn1002-0306.2020120115
Abstract:
To analyze the effects of β-glucosidase on the aroma characteristics of Rosa roxburghii Tratt (Rosa roxburghii) wine, a strain of Wickerhamomyces anomalus (W. anomalus) C4 producing β-glucosidase was used as the starting strain, and its β-glucosidase activity was further improved by mutagenesis using ethylmethanesulfonate (EMS). R. roxburghii wine was produced via pure or mixed inoculatation of W. anomalus or together with Saccharomyces cerevisiae. The β-glycosidase producing ability was examined using p-nitrophenyl-β-D-glucopyranoside colorimetry. Headspace solid phase microextraction (HS-SPME) and gas phase mass spectrometry (GC-MS) were performed to determine the volatile aroma substances of each group of R. roxburghii wine. A mutant strain W.anomalus E3 with stable β-glucosidase produced activity was obtained using the mutagenic agent EMS, and the enzyme activity of W.anomalus E3 was (55.05±1.74) U/L, which increased 31.70% compared with the starting strain W.anomalus C4. β-glucosidase activity increased gradually, reached its maximum at the 10th day, and then decreased rapidly during the fermentation process of R. roxburghii wine. Inoculation with W.anomalus C4 and E3 could reduce theacidity value including total acid, volatile acid and pH of the R. roxburghii wine, and the total sugar content was also decreased. Moreover, inoculation with W.anomalus C4 and E3 also regulate the aroma characteristics, such as increasing the volatile ester and alcohol content and the OAVs of the main aroma components. Therefore, it was helpful to regulate the aroma characteristics and increase the complexity and richness of the R. roxburghii wine when inoculation with W.anomalus strain producing β-glucosidase.
To analyze the effects of β-glucosidase on the aroma characteristics of Rosa roxburghii Tratt (Rosa roxburghii) wine, a strain of Wickerhamomyces anomalus (W. anomalus) C4 producing β-glucosidase was used as the starting strain, and its β-glucosidase activity was further improved by mutagenesis using ethylmethanesulfonate (EMS). R. roxburghii wine was produced via pure or mixed inoculatation of W. anomalus or together with Saccharomyces cerevisiae. The β-glycosidase producing ability was examined using p-nitrophenyl-β-D-glucopyranoside colorimetry. Headspace solid phase microextraction (HS-SPME) and gas phase mass spectrometry (GC-MS) were performed to determine the volatile aroma substances of each group of R. roxburghii wine. A mutant strain W.anomalus E3 with stable β-glucosidase produced activity was obtained using the mutagenic agent EMS, and the enzyme activity of W.anomalus E3 was (55.05±1.74) U/L, which increased 31.70% compared with the starting strain W.anomalus C4. β-glucosidase activity increased gradually, reached its maximum at the 10th day, and then decreased rapidly during the fermentation process of R. roxburghii wine. Inoculation with W.anomalus C4 and E3 could reduce theacidity value including total acid, volatile acid and pH of the R. roxburghii wine, and the total sugar content was also decreased. Moreover, inoculation with W.anomalus C4 and E3 also regulate the aroma characteristics, such as increasing the volatile ester and alcohol content and the OAVs of the main aroma components. Therefore, it was helpful to regulate the aroma characteristics and increase the complexity and richness of the R. roxburghii wine when inoculation with W.anomalus strain producing β-glucosidase.
2021, 42(19): 126-134.
doi: 10.13386/j.issn1002-0306.2020120275
Abstract:
Objective: Microbial species level identification in Chinese liquor fermentation, key enzymatic character and enzymatic mechanism study benefits to improve quality of Chinese liquor. Methods: Based on the morphological and physiological characteristics, 16S rRNA, gyrB gene and antiSMASH analysis to identify a micro-organism. 3D model by 3D structure modeling was gained and the mechanism regulating by molecular docking was insighted. Results: The strain was identified as gram-negative Bacillus velezensis with carboxylesterase gene. The growth curve was typical S-shaped growth curve. Product curve was typical S-shaped. The range of carboxylesterase-activity was from pH5.0 to pH9.0. Molecular docking indicated that Phe21A was responsible for the primarily hydrolysis reaction in catalytic site where glyceryl tributyrate was hydrolyzed into glycerol and butyric acid. Glyceryl tributyrate experiencing conformational changes were transported into catalytic site and then hydrolysed; Interactions of hydrophilic and hydrophobic interface were beneficial to the substrate transferred downward. The hydrolyzed substrates went to the enzyme surface from hydrophobic channel. Conclusion: The stain is identificated as gram-negative Bacillus velezensis with carboxylesterase gene and this study provides a new view of substrate recognition, transfer and catalysis mechanism when carboxylesterase hydrolyzes substances, such as glyceryl tributyrate.
Objective: Microbial species level identification in Chinese liquor fermentation, key enzymatic character and enzymatic mechanism study benefits to improve quality of Chinese liquor. Methods: Based on the morphological and physiological characteristics, 16S rRNA, gyrB gene and antiSMASH analysis to identify a micro-organism. 3D model by 3D structure modeling was gained and the mechanism regulating by molecular docking was insighted. Results: The strain was identified as gram-negative Bacillus velezensis with carboxylesterase gene. The growth curve was typical S-shaped growth curve. Product curve was typical S-shaped. The range of carboxylesterase-activity was from pH5.0 to pH9.0. Molecular docking indicated that Phe21A was responsible for the primarily hydrolysis reaction in catalytic site where glyceryl tributyrate was hydrolyzed into glycerol and butyric acid. Glyceryl tributyrate experiencing conformational changes were transported into catalytic site and then hydrolysed; Interactions of hydrophilic and hydrophobic interface were beneficial to the substrate transferred downward. The hydrolyzed substrates went to the enzyme surface from hydrophobic channel. Conclusion: The stain is identificated as gram-negative Bacillus velezensis with carboxylesterase gene and this study provides a new view of substrate recognition, transfer and catalysis mechanism when carboxylesterase hydrolyzes substances, such as glyceryl tributyrate.
2021, 42(19): 135-143.
doi: 10.13386/j.issn1002-0306.2021030041
Abstract:
In this study, Cupei was used as the research object in solid-state fermentation process of Sichuan Sun vinegar (SV), the bacterial community structure and richness were analyzed by high-throughput sequencing. The results showed that a total of 166 genera of bacterial communities were detected in Cupei during the whole fermentation process. On the 15th day of fermentation, a total of 79 genera in 45 families in 36 orders in 14 classes in 11 phyla were obtained by operational taxon analysis (OTUs), which was the highest among all samples. UPGMA cluster analysis was used to preliminarily explore the boundary nodes of saccharification, alcohol fermentation and acetic acid fermentation in the co-fermentation, during the first three days of fermentation, the dominant bacteria are Lactobacillus and Weissella. Lactobacillus and Acetobacter were the dominant bacteria at the middle fermentation period, and the richness and diversity of bacteria community were reached the highest value on the 7th day of fermentation. At the later fermentation stage (13~17 d), the dominant bacteria were Acetobacter, Cupriavidus, Pelomonas and Sphingomonas. This research revealed the bacterial community succession during the solid-state fermentation of Sun vinegar, which provided a theoretical basis for microbial community structure in solid-state fermentation of Sun vinegar.
In this study, Cupei was used as the research object in solid-state fermentation process of Sichuan Sun vinegar (SV), the bacterial community structure and richness were analyzed by high-throughput sequencing. The results showed that a total of 166 genera of bacterial communities were detected in Cupei during the whole fermentation process. On the 15th day of fermentation, a total of 79 genera in 45 families in 36 orders in 14 classes in 11 phyla were obtained by operational taxon analysis (OTUs), which was the highest among all samples. UPGMA cluster analysis was used to preliminarily explore the boundary nodes of saccharification, alcohol fermentation and acetic acid fermentation in the co-fermentation, during the first three days of fermentation, the dominant bacteria are Lactobacillus and Weissella. Lactobacillus and Acetobacter were the dominant bacteria at the middle fermentation period, and the richness and diversity of bacteria community were reached the highest value on the 7th day of fermentation. At the later fermentation stage (13~17 d), the dominant bacteria were Acetobacter, Cupriavidus, Pelomonas and Sphingomonas. This research revealed the bacterial community succession during the solid-state fermentation of Sun vinegar, which provided a theoretical basis for microbial community structure in solid-state fermentation of Sun vinegar.
2021, 42(19): 144-151.
doi: 10.13386/j.issn1002-0306.2021030061
Abstract:
Objective: The study of V. parahaemolyticus specific surface antigens is of importance to develop immunoassays of immune detection. The immunogenicity study of V. parahaemolyticus differential outer membrane protein (VP1008) and ferric vibrioferrin receptor (pvuA) has not been revealed. Methods: The target genes were amplified from the genome DNA and the recombinant plasmids pET-28a(+) were respectively constructed and transformed into E. coli BL21. The two recombinant proteins were both induced by Isopropyl-β-D-Thiogalactoside (IPTG). After purified by a NI-NTA column, the purified recombinant proteins were immunized to the BALB/c mice. The cross-reaction of the polyclone antibodies (pAb) with different isolates of V. parahaemolyticus and other Vibrio species was studied by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results: The recombinant protein VP1008 and Vibrio ferritin receptor were expressed as inclusion bodies, the pAb both strongly reacted to the corresponding recombinant protein (>1000 K), reacted with 7 strains of V. parahaemolyticus (4.5~13.5 K), and basically did not react with 10 strains of Vibrio, the cross-reaction with Enterobacteriaceae strains was related with the residual proteins of E. coli during the purification steps. The pAb also both reacted with the target protein in the cell lysates of the V. parahaemolyticus strains. Comparatively, the pAb against VP1008 had a higher antibody titer and immunogenicity. Conclusion: The pAb against the recombinant Omp VP1008 recognized the V. parahaemolyticus strains with higher titer, which laid the foundation for preparing a new immunoassay against V. parahaemolyticus.
Objective: The study of V. parahaemolyticus specific surface antigens is of importance to develop immunoassays of immune detection. The immunogenicity study of V. parahaemolyticus differential outer membrane protein (VP1008) and ferric vibrioferrin receptor (pvuA) has not been revealed. Methods: The target genes were amplified from the genome DNA and the recombinant plasmids pET-28a(+) were respectively constructed and transformed into E. coli BL21. The two recombinant proteins were both induced by Isopropyl-β-D-Thiogalactoside (IPTG). After purified by a NI-NTA column, the purified recombinant proteins were immunized to the BALB/c mice. The cross-reaction of the polyclone antibodies (pAb) with different isolates of V. parahaemolyticus and other Vibrio species was studied by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results: The recombinant protein VP1008 and Vibrio ferritin receptor were expressed as inclusion bodies, the pAb both strongly reacted to the corresponding recombinant protein (>1000 K), reacted with 7 strains of V. parahaemolyticus (4.5~13.5 K), and basically did not react with 10 strains of Vibrio, the cross-reaction with Enterobacteriaceae strains was related with the residual proteins of E. coli during the purification steps. The pAb also both reacted with the target protein in the cell lysates of the V. parahaemolyticus strains. Comparatively, the pAb against VP1008 had a higher antibody titer and immunogenicity. Conclusion: The pAb against the recombinant Omp VP1008 recognized the V. parahaemolyticus strains with higher titer, which laid the foundation for preparing a new immunoassay against V. parahaemolyticus.
2021, 42(19): 152-162.
doi: 10.13386/j.issn1002-0306.2021030196
Abstract:
In order to deeply analyze the flavor contribution and characteristic aroma components of Lactococcus lactis in fermented milk, twenty-one strains of Lactococcus lactis were isolated from different commercial starters, and subjected to single-strain fermentation. The aroma type was defined according to the results of sensory evaluation, and then determination of volatile flavor compounds in fermented milk was performed using GC-IMS technology, and finally flavor substances were analyzed by chemometric method. The results showed that these single-strain fermented milk can be divided into three flavor types: Milk flavor, cream flavor, and butter flavor. Twenty-five compounds were identified by GC-IMS, including nine alcohols, eight ketones, three aldehydes, one carboxylic acid, and four esters. By drawing the GC-IMS fingerprint map, the characteristic compound composition of fermented milk from different strains was presented. The fermented milks of four strains of Lactococcus lactis subsp. lactis var. diacetylactis were well distinguished by principal component analysis, and the results were consistent with the sensory evaluation results. The correlation between sensory flavor classification and volatile components was analyzed by PLSR, and it was found that the volatile flavor components that had a greater contribution to the “butter flavor” were 1-hexanal and 1-hexanol, the compound which had a greater contribution to the “creamy flavor” was ethyl acetate, the compounds which contributed to the “milk flavor” were obscure, and further analysis was needed for revealing the key ingredients. This research provides a reference for exerting the flavor enhancement effect of Lactococcus lactis in fermented milk.
In order to deeply analyze the flavor contribution and characteristic aroma components of Lactococcus lactis in fermented milk, twenty-one strains of Lactococcus lactis were isolated from different commercial starters, and subjected to single-strain fermentation. The aroma type was defined according to the results of sensory evaluation, and then determination of volatile flavor compounds in fermented milk was performed using GC-IMS technology, and finally flavor substances were analyzed by chemometric method. The results showed that these single-strain fermented milk can be divided into three flavor types: Milk flavor, cream flavor, and butter flavor. Twenty-five compounds were identified by GC-IMS, including nine alcohols, eight ketones, three aldehydes, one carboxylic acid, and four esters. By drawing the GC-IMS fingerprint map, the characteristic compound composition of fermented milk from different strains was presented. The fermented milks of four strains of Lactococcus lactis subsp. lactis var. diacetylactis were well distinguished by principal component analysis, and the results were consistent with the sensory evaluation results. The correlation between sensory flavor classification and volatile components was analyzed by PLSR, and it was found that the volatile flavor components that had a greater contribution to the “butter flavor” were 1-hexanal and 1-hexanol, the compound which had a greater contribution to the “creamy flavor” was ethyl acetate, the compounds which contributed to the “milk flavor” were obscure, and further analysis was needed for revealing the key ingredients. This research provides a reference for exerting the flavor enhancement effect of Lactococcus lactis in fermented milk.
More+
2021, 42(19): 163-172.
doi: 10.13386/j.issn1002-0306.2020110210
Abstract:
With the amniotic bacteria sub-entity as the main raw material, by cellulase, papaya protease complex enzyme solution, ultrasound assisted extraction to obtain Morchella esculenta polysaccharides
With the amniotic bacteria sub-entity as the main raw material, by cellulase, papaya protease complex enzyme solution, ultrasound assisted extraction to obtain Morchella esculenta polysaccharides
2021, 42(19): 173-181.
doi: 10.13386/j.issn1002-0306.2020110215
Abstract:
In order to avoid the production of okara in soybean milk industry, whole soybean milk (WSM)was prepared using dehulled soybeans as raw materials by high-pressure microfluidizer without filtration process, and the storage stability of WSM was also studied. Taking sensory evaluation and stability as indicators, according to single factor and orthogonal experiments, the optimum process parameters of preparing whole soybean milk were as follows: the ratio of material to water was 1:8 (w/w), the content of soluble solid was 10%, the pressure of microfluidizer was 90 MPa, the steam heating condition was 5 min at 95 ℃, the added amount of sugar was 4% and the sterilization condition was 145 ℃ for 5 s. The results of storage experiment showed that the whole soybean milk prepared by this optimized process possessed the best sensory score and excellent stability. The soymilk showed no precipitation and stratification within 90 days at 4 ℃, and the total number of bacterial colonies met the national standard of soybean milk products. According to the shelf-life calculation, it was estimated that the shelf life of WSM could reach 8 months under the storage of 4 ℃ and 3 months under the storage of room temperature (25 ℃). In summary, the optimized process could prepare a kind of WSM that was self-stable and had a good taste and flavor without filtering and adding stabilizer.
In order to avoid the production of okara in soybean milk industry, whole soybean milk (WSM)was prepared using dehulled soybeans as raw materials by high-pressure microfluidizer without filtration process, and the storage stability of WSM was also studied. Taking sensory evaluation and stability as indicators, according to single factor and orthogonal experiments, the optimum process parameters of preparing whole soybean milk were as follows: the ratio of material to water was 1:8 (w/w), the content of soluble solid was 10%, the pressure of microfluidizer was 90 MPa, the steam heating condition was 5 min at 95 ℃, the added amount of sugar was 4% and the sterilization condition was 145 ℃ for 5 s. The results of storage experiment showed that the whole soybean milk prepared by this optimized process possessed the best sensory score and excellent stability. The soymilk showed no precipitation and stratification within 90 days at 4 ℃, and the total number of bacterial colonies met the national standard of soybean milk products. According to the shelf-life calculation, it was estimated that the shelf life of WSM could reach 8 months under the storage of 4 ℃ and 3 months under the storage of room temperature (25 ℃). In summary, the optimized process could prepare a kind of WSM that was self-stable and had a good taste and flavor without filtering and adding stabilizer.
2021, 42(19): 182-189.
doi: 10.13386/j.issn1002-0306.2020120097
Abstract:
Ultrasound-assisted enzyme extraction method was used to extract collagen peptide of boneless chicken feet. Alcalase was selected to hydrolyze collagen from five commercial enzymes (papain, alkaline protease, complex protease, pepsin and trypsin) and the yield of collagen peptide was used as an indicator. On that basis, the single-factor experiments were carried out with material-liquid ratio, ultrasonic power, ultrasonic time and enzyme extraction time. Then, with collagen peptide yield as the response value, three factors that significantly affected enzymatic hydrolysis were selected for response surface analysis to conduct three-factor three-level experiments. The results showed that the influence of various factors on the extraction rate was as follows: material-liquid ratio>enzyme extraction time>ultrasonic power. The optimal extraction process was the material-liquid ratio of 1:26 (g/mL), ultrasonic power of 250 W and the extraction time of 4 h, and the final collagen peptide yield was 49.24%±0.98%. The solubility of the collagen peptide from boneless chicken feet obtained by process optimization was above 90%. Therefore, Ultrasound-assisted enzyme extraction method can be used in processing industrial production to expand the application market of chicken by-product collagen.
Ultrasound-assisted enzyme extraction method was used to extract collagen peptide of boneless chicken feet. Alcalase was selected to hydrolyze collagen from five commercial enzymes (papain, alkaline protease, complex protease, pepsin and trypsin) and the yield of collagen peptide was used as an indicator. On that basis, the single-factor experiments were carried out with material-liquid ratio, ultrasonic power, ultrasonic time and enzyme extraction time. Then, with collagen peptide yield as the response value, three factors that significantly affected enzymatic hydrolysis were selected for response surface analysis to conduct three-factor three-level experiments. The results showed that the influence of various factors on the extraction rate was as follows: material-liquid ratio>enzyme extraction time>ultrasonic power. The optimal extraction process was the material-liquid ratio of 1:26 (g/mL), ultrasonic power of 250 W and the extraction time of 4 h, and the final collagen peptide yield was 49.24%±0.98%. The solubility of the collagen peptide from boneless chicken feet obtained by process optimization was above 90%. Therefore, Ultrasound-assisted enzyme extraction method can be used in processing industrial production to expand the application market of chicken by-product collagen.
2021, 42(19): 190-196.
doi: 10.13386/j.issn1002-0306.2020120293
Abstract:
The Physalis pubescens L. seeds defatted as materials, the extraction rate of protein as index, on the basis of single factor experiments, such as ultrasonic power, extraction temperature, extraction time and extraction solution pH, the optimal extraction conditions were optimized by orthogonal experiment, and the solubility, emulsibility and foamability properties of the protein were analyzed. The extraction conditions of protein from Physalis pubescens L. seeds by ultrasonic-assisted alkali-soluble acid-precipitation method were optimized by orthogonal experiment. The solubility, emulsibility and foamability of the protein were analyzed. The results showed that the influence order of various factors on the extraction rate of protein was as follows: Extraction temperature>ultrasonic power>extraction solution pH>extraction time. When solid-liquid ratio was 1:15(g/mL), the optimum conditions of protein from Physalis pubescens L. seeds by ultrasound-assisted treatment were as follows: The extraction temperature 50 ℃, the extraction power 300 W, the pH of the extract solution 9.0, and the extraction time 50 min. Under this condition, the extraction rate of protein from Physalis pubescens L. seeds could reach 90.45%±0.16%. The protein from Physalis pubescens L. seeds extracted by ultrasonic-assisted method had the best solubility and emulsification when pH was 10.0, with the nitrogen solubility index (NSI) of 58.32% and the emulsification ability of 68.94 m2/g, and the foaming characteristic of the protein was the best at pH7.0, which was 43%. The extraction process can efficiently extract the protein from Physalis pubescens L. seeds, which provides a theoretical basis for the further application of the protein.
The Physalis pubescens L. seeds defatted as materials, the extraction rate of protein as index, on the basis of single factor experiments, such as ultrasonic power, extraction temperature, extraction time and extraction solution pH, the optimal extraction conditions were optimized by orthogonal experiment, and the solubility, emulsibility and foamability properties of the protein were analyzed. The extraction conditions of protein from Physalis pubescens L. seeds by ultrasonic-assisted alkali-soluble acid-precipitation method were optimized by orthogonal experiment. The solubility, emulsibility and foamability of the protein were analyzed. The results showed that the influence order of various factors on the extraction rate of protein was as follows: Extraction temperature>ultrasonic power>extraction solution pH>extraction time. When solid-liquid ratio was 1:15(g/mL), the optimum conditions of protein from Physalis pubescens L. seeds by ultrasound-assisted treatment were as follows: The extraction temperature 50 ℃, the extraction power 300 W, the pH of the extract solution 9.0, and the extraction time 50 min. Under this condition, the extraction rate of protein from Physalis pubescens L. seeds could reach 90.45%±0.16%. The protein from Physalis pubescens L. seeds extracted by ultrasonic-assisted method had the best solubility and emulsification when pH was 10.0, with the nitrogen solubility index (NSI) of 58.32% and the emulsification ability of 68.94 m2/g, and the foaming characteristic of the protein was the best at pH7.0, which was 43%. The extraction process can efficiently extract the protein from Physalis pubescens L. seeds, which provides a theoretical basis for the further application of the protein.
2021, 42(19): 197-203.
doi: 10.13386/j.issn1002-0306.2021010006
Abstract:
In this study, silver carp and cod were selected as main raw materials, potato starch, Glutamine transaminase (TGase) and egg white protein as the single factor. The composite surimi gel strength was used as the response value. Box-Behnken response surface test was used to optimize the performance of composite surimi gel. The optimum composite surimi gel properties were verified by texture analysis and scanning electron microscope. The results showed that the amount of silver carp and cod surimi in potato starch was 16%, Glutamine transaminase (TGase) added 0.4%, egg white protein added 6.0%, the gel strength of composite surimi was the largest. According to the formula (optimized process group), the masticatory, adhesive, breaking force and breaking distance of the composite chymotryme texture parameters were significantly higher than those of the common process group without adding exogenous substances (P<0.05). At the same time, the SEM of the composite surimi of the optimized process group showed that the gel structure was dense, the gel holes were small, it is proved that exogenous additives can improve the strength of composite surimi gel.
In this study, silver carp and cod were selected as main raw materials, potato starch, Glutamine transaminase (TGase) and egg white protein as the single factor. The composite surimi gel strength was used as the response value. Box-Behnken response surface test was used to optimize the performance of composite surimi gel. The optimum composite surimi gel properties were verified by texture analysis and scanning electron microscope. The results showed that the amount of silver carp and cod surimi in potato starch was 16%, Glutamine transaminase (TGase) added 0.4%, egg white protein added 6.0%, the gel strength of composite surimi was the largest. According to the formula (optimized process group), the masticatory, adhesive, breaking force and breaking distance of the composite chymotryme texture parameters were significantly higher than those of the common process group without adding exogenous substances (P<0.05). At the same time, the SEM of the composite surimi of the optimized process group showed that the gel structure was dense, the gel holes were small, it is proved that exogenous additives can improve the strength of composite surimi gel.
2021, 42(19): 204-210.
doi: 10.13386/j.issn1002-0306.2021010036
Abstract:
In order to improve the utilization rate of the coelomic fluid of Phascoloma esculenta, the optimal extraction technology and its antioxidant properties in vitro were explored. The polysaccharide of Phascoloma esculenta was extracted by alkali extraction method and optimized by orthogonal experiment. The total reducing power, DPPH scavenging rate and hydroxyl radical scavenging rate were used to determine its antioxidant properties. The composition of monosaccharides was determined by high performance liquid chromatography, and the polysaccharide composition was analyzed by infrared spectroscopy. The results showed that the optimal extraction process conditions for polysaccharides from the coelomic fluid of Phascoloma esculenta were extraction temperature of 50 ℃, alkaline extraction time of 3 h, and NaOH concentration of 1.5%. The yield of polysaccharides under this process was 0.92%. The half scavenging concentration (IC50) of the total reducing power, DPPH scavenging rate and hydroxyl radical scavenging rate were 2.976, 0.567 and 0.605 mg/mL, respectively. The results of HPLC showed that the polysaccharide was mainly composed of glucose and infrared spectroscopy showed that the polysaccharide contained acetylamino and pyran rings and connected by α-glycosidic bonds. It could be seen that the polysaccharides from the coelomic fluid of Phascoloma esculenta have good antioxidant properties and application prospect.
In order to improve the utilization rate of the coelomic fluid of Phascoloma esculenta, the optimal extraction technology and its antioxidant properties in vitro were explored. The polysaccharide of Phascoloma esculenta was extracted by alkali extraction method and optimized by orthogonal experiment. The total reducing power, DPPH scavenging rate and hydroxyl radical scavenging rate were used to determine its antioxidant properties. The composition of monosaccharides was determined by high performance liquid chromatography, and the polysaccharide composition was analyzed by infrared spectroscopy. The results showed that the optimal extraction process conditions for polysaccharides from the coelomic fluid of Phascoloma esculenta were extraction temperature of 50 ℃, alkaline extraction time of 3 h, and NaOH concentration of 1.5%. The yield of polysaccharides under this process was 0.92%. The half scavenging concentration (IC50) of the total reducing power, DPPH scavenging rate and hydroxyl radical scavenging rate were 2.976, 0.567 and 0.605 mg/mL, respectively. The results of HPLC showed that the polysaccharide was mainly composed of glucose and infrared spectroscopy showed that the polysaccharide contained acetylamino and pyran rings and connected by α-glycosidic bonds. It could be seen that the polysaccharides from the coelomic fluid of Phascoloma esculenta have good antioxidant properties and application prospect.
2021, 42(19): 211-217.
doi: 10.13386/j.issn1002-0306.2021010058
Abstract:
The purification process of total flavonoids that extract from roots of Cirsium japonicum DC. with macroporous resin was optimized by response surface experiments based on single factor tests, and anti-bacterial activity of flavonoid were compared before and after purification. The static adsorption and desorption performances of different types macroporous resin were observed by static adsorption-desorption experiment for confirmed the best type resin. Then, the best purified process was determined by dynamic adsorption-desorption experiment. Meanwhile, the resistant abilities against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis of two products were detected by filtering paper method. The results showed that D101 was the best purified resin. The optimal parameters for purification were as follows: the sample concentration of 2.96 mg/mL, the sample pH value of 4.97, the sample flow rate of 1.0 mL/min, ethanol concentration of 70.2% eluting agent volume of 180 mL, and desorption rate of 1.0 mL/min. Under these conditions, total flavonoids had a recovery rate of 69.8% and a purity of 67.4%. The results of anti-bacterial test in vitro showed that compared with extract, the diameter of inhibition zone which flavonoid after purification inhibited three tested bacteria were obviously all increasing (P<0.05). Therefore, its anti-bacterial activity was better.
The purification process of total flavonoids that extract from roots of Cirsium japonicum DC. with macroporous resin was optimized by response surface experiments based on single factor tests, and anti-bacterial activity of flavonoid were compared before and after purification. The static adsorption and desorption performances of different types macroporous resin were observed by static adsorption-desorption experiment for confirmed the best type resin. Then, the best purified process was determined by dynamic adsorption-desorption experiment. Meanwhile, the resistant abilities against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis of two products were detected by filtering paper method. The results showed that D101 was the best purified resin. The optimal parameters for purification were as follows: the sample concentration of 2.96 mg/mL, the sample pH value of 4.97, the sample flow rate of 1.0 mL/min, ethanol concentration of 70.2% eluting agent volume of 180 mL, and desorption rate of 1.0 mL/min. Under these conditions, total flavonoids had a recovery rate of 69.8% and a purity of 67.4%. The results of anti-bacterial test in vitro showed that compared with extract, the diameter of inhibition zone which flavonoid after purification inhibited three tested bacteria were obviously all increasing (P<0.05). Therefore, its anti-bacterial activity was better.
2021, 42(19): 218-225.
doi: 10.13386/j.issn1002-0306.2021010186
Abstract:
Ultrasonic assisted aqueous two-phase extraction of total flavonoid from loquat flower and its antioxidant activity were studied. With the yield of total flavonoid as the index, the extraction conditions were optimized by single factor test and response surface design, and the antioxidant effect was evaluated by measuring the damage of H2O2, the scavenging rate of ·OH and total reducing power.The results showed that the optimum extraction condition were determined as follows: The time of ultrasonic was 45 min, the mass content of loquat flower, (NH4)2SO4 and PEG400 was 0.2%, 18% and 28%. By adopting the process, the extraction yield of total flavonoid from loquat flower was 26.96%.The damage of H2O2 to total flavonoid was not obvious, the half scavenging concentration (IC50) values of ·OH was 0.297 mg/mL.The scavenging effect was superior to vitamin C (VC). The results suggest that total flavonoid from loquat flower is potential natural antioxidant.
Ultrasonic assisted aqueous two-phase extraction of total flavonoid from loquat flower and its antioxidant activity were studied. With the yield of total flavonoid as the index, the extraction conditions were optimized by single factor test and response surface design, and the antioxidant effect was evaluated by measuring the damage of H2O2, the scavenging rate of ·OH and total reducing power.The results showed that the optimum extraction condition were determined as follows: The time of ultrasonic was 45 min, the mass content of loquat flower, (NH4)2SO4 and PEG400 was 0.2%, 18% and 28%. By adopting the process, the extraction yield of total flavonoid from loquat flower was 26.96%.The damage of H2O2 to total flavonoid was not obvious, the half scavenging concentration (IC50) values of ·OH was 0.297 mg/mL.The scavenging effect was superior to vitamin C (VC). The results suggest that total flavonoid from loquat flower is potential natural antioxidant.
2021, 42(19): 226-237.
doi: 10.13386/j.issn1002-0306.2021020074
Abstract:
The sugar-free probiotic preserved kiwifruit was processed by the microwave-ultrasonic synergistic sugar penetration method. Based on the results of single-factor experiments, the response surface test was used to optimize the processing technology of preserved kiwifruit, and a regression digital model was established. It showed that the optimal process conditions were determined as follows: 28% xylitol addition, 0.16% excipient compound addition, microwave 35 min-ultrasound 1.25 h, the comprehensive score of the total sugar content and sensory evaluation of the obtained product was 61.93. Nutritional quality analysis showed that microwave-ultrasonic synergistic sugar penetration could not only greatly improve the sugar infiltration effect, but also reduce the loss of Vc, which maintained 86% of fresh kiwifruit Vc, and increased the contents of free amino acids, total phenols and flavonoids by 52%, 38% and 56%, respectively.High performance liquid chromatography (HPLC) analysis showed that the contents of 7 kinds of organic acids in the preserved kiwifruit processed with microwave-ultrasonic synergistic sugar penetration increased, including citric acid, malic acid, tartaric acid, and quinic acid, etc. Gas chromatography-mass spectrometry (GC-MS) analysis results showed that the main volatile flavor compounds of kiwifruit were changed from 2-hexenal to ethyl caproate after kiwifruit was processed into sugar-free probiotic preserved kiwifruit. It showed that microwave-ultrasonic synergistic sugar penetration treatment preserved the original flavor of kiwifruit to the greatest extent, more flavor substances such as fruit aroma and lipid aroma were produced at the same time, which made the preserved kiwifruit more flavorful.
The sugar-free probiotic preserved kiwifruit was processed by the microwave-ultrasonic synergistic sugar penetration method. Based on the results of single-factor experiments, the response surface test was used to optimize the processing technology of preserved kiwifruit, and a regression digital model was established. It showed that the optimal process conditions were determined as follows: 28% xylitol addition, 0.16% excipient compound addition, microwave 35 min-ultrasound 1.25 h, the comprehensive score of the total sugar content and sensory evaluation of the obtained product was 61.93. Nutritional quality analysis showed that microwave-ultrasonic synergistic sugar penetration could not only greatly improve the sugar infiltration effect, but also reduce the loss of Vc, which maintained 86% of fresh kiwifruit Vc, and increased the contents of free amino acids, total phenols and flavonoids by 52%, 38% and 56%, respectively.High performance liquid chromatography (HPLC) analysis showed that the contents of 7 kinds of organic acids in the preserved kiwifruit processed with microwave-ultrasonic synergistic sugar penetration increased, including citric acid, malic acid, tartaric acid, and quinic acid, etc. Gas chromatography-mass spectrometry (GC-MS) analysis results showed that the main volatile flavor compounds of kiwifruit were changed from 2-hexenal to ethyl caproate after kiwifruit was processed into sugar-free probiotic preserved kiwifruit. It showed that microwave-ultrasonic synergistic sugar penetration treatment preserved the original flavor of kiwifruit to the greatest extent, more flavor substances such as fruit aroma and lipid aroma were produced at the same time, which made the preserved kiwifruit more flavorful.
2021, 42(19): 238-246.
doi: 10.13386/j.issn1002-0306.2021020142
Abstract:
Mung beans as raw materials were used to prepare probiotic-rich mung bean powder, the preparation process conditions were optimized. The applicability of the preparation process conditions to different miscellaneous beans were verified, and the shelf life of different miscellaneous bean powders were explored. The Plackett-Burman design was used to select soaking temperature, homogenization pressure, and inlet temperature as three of the eight significant factors that affect the fermentation in mung bean powder. The best process parameters were as follows: soaking temperature 50 ℃, homogenizing pressure 200 Bar and inlet temperature 115 ℃ as determined by the Box-Behnken design. Under these conditions, the experimental value of Lactobacillus fermentum in mung bean powder was 2.39×108 CFU/g, which was not significantly different from the predicted value of 2.46×108 CFU/g. In addition, by examining the effects of this optimized condition on red beans, chickpeas, cowpeas, peas and tiger skin kidney beans, it was found that the bacterial activity in the bean powder could exceed 107 CFU/g. This was met the requirements of probiotic foods. Among them, tiger skin kidney bean powder was the highest, reaching 3.27×108 CFU/g, indicating that these conditions had universal applicability for miscellaneous beans. The Arrhenius model predicted that the storage temperature of the bean powder products for one year should be less than 10 ℃. In addition, the moisture content in the miscellaneous bean powder were low, which were conducive to storage.
Mung beans as raw materials were used to prepare probiotic-rich mung bean powder, the preparation process conditions were optimized. The applicability of the preparation process conditions to different miscellaneous beans were verified, and the shelf life of different miscellaneous bean powders were explored. The Plackett-Burman design was used to select soaking temperature, homogenization pressure, and inlet temperature as three of the eight significant factors that affect the fermentation in mung bean powder. The best process parameters were as follows: soaking temperature 50 ℃, homogenizing pressure 200 Bar and inlet temperature 115 ℃ as determined by the Box-Behnken design. Under these conditions, the experimental value of Lactobacillus fermentum in mung bean powder was 2.39×108 CFU/g, which was not significantly different from the predicted value of 2.46×108 CFU/g. In addition, by examining the effects of this optimized condition on red beans, chickpeas, cowpeas, peas and tiger skin kidney beans, it was found that the bacterial activity in the bean powder could exceed 107 CFU/g. This was met the requirements of probiotic foods. Among them, tiger skin kidney bean powder was the highest, reaching 3.27×108 CFU/g, indicating that these conditions had universal applicability for miscellaneous beans. The Arrhenius model predicted that the storage temperature of the bean powder products for one year should be less than 10 ℃. In addition, the moisture content in the miscellaneous bean powder were low, which were conducive to storage.
2021, 42(19): 247-254.
doi: 10.13386/j.issn1002-0306.2021040259
Abstract:
Edible Jiaosu gel was prepared with sodium alginate, chitosan and mulberry Jiaosu as raw materials, and calcium chloride as ionic cross-linking agent. The effects of the mass ratio of sodium alginate to chitosan, cross-linking time, and calcium chloride concentration on the hardness, gumminess and chewiness of the Jiaosu gel were studied by single factor experiment and Box-Behnken response surface methodology. The results showed that the optimal preparation process of Jiaosu gel was as follows: the mass ratio of sodium alginate to chitosan 5:2.82, the cross-linking time 131 min, and the concentration of calcium chloride 17.9 mg/mL. Under the optimized conditions, the hardness of the Jiaosu gel was 7.19 N, the adhesiveness was 6.60 N, and the chewiness was 0.70 kgf. The optimized results are accurate and reliable, which can provide theoretical basis and technical reference for the further development and utilization of functional food of Jiaosu.
Edible Jiaosu gel was prepared with sodium alginate, chitosan and mulberry Jiaosu as raw materials, and calcium chloride as ionic cross-linking agent. The effects of the mass ratio of sodium alginate to chitosan, cross-linking time, and calcium chloride concentration on the hardness, gumminess and chewiness of the Jiaosu gel were studied by single factor experiment and Box-Behnken response surface methodology. The results showed that the optimal preparation process of Jiaosu gel was as follows: the mass ratio of sodium alginate to chitosan 5:2.82, the cross-linking time 131 min, and the concentration of calcium chloride 17.9 mg/mL. Under the optimized conditions, the hardness of the Jiaosu gel was 7.19 N, the adhesiveness was 6.60 N, and the chewiness was 0.70 kgf. The optimized results are accurate and reliable, which can provide theoretical basis and technical reference for the further development and utilization of functional food of Jiaosu.
More+
2021, 42(19): 255-260.
doi: 10.13386/j.issn1002-0306.2021030219
Abstract:
The aim of this study was to investigate the synergistic effect of Sanxan (SAN) and Sodium alginate (SA) and the properties of composite film. SAN and SA were mixed at different mass ratios, and glycerin was added as plasticizer to prepare composite films. The tensile strength of films, elongation at break, light transmittance, solubility and water vapor transmittance were measured. Differential scanning calorimetry analysis of composite films was carried out. The microstructure of films was characterized by fourier transform infrared spectrum and scanning electron microscope. The results showed that the tensile strength of the SAN/SA film with the mass ratio of 5:5 was the highest, and the difference between the film with the ratio of 4:6 was not significant (P>0.05), but was significantly higher than that of other films (P<0.05). The flexibility of film with SAN/SA mass ratio of 6:4 was significantly increased (P<0.05), the water vapor transmittance and solubility of this film were the lowest. Differential scanning calorimetry analysis showed that the heat resistance of the composite film was improved. According to the results of fourier transform infrared spectrum, hydrogen bond interaction existed between SAN and SA molecules, indicating good compatibility and synergistic effect between them. The microstructure showed that the network structure of the composite film was arranged more orderly and the pores of the film surface were smaller. The results showed that SAN had a good synergistic effect with sodium alginate, and the properties of SAN/SA composite film were significantly improved. As a newly approved natural polymer which can be used in the food field, the application prospect of SAN is broad.
The aim of this study was to investigate the synergistic effect of Sanxan (SAN) and Sodium alginate (SA) and the properties of composite film. SAN and SA were mixed at different mass ratios, and glycerin was added as plasticizer to prepare composite films. The tensile strength of films, elongation at break, light transmittance, solubility and water vapor transmittance were measured. Differential scanning calorimetry analysis of composite films was carried out. The microstructure of films was characterized by fourier transform infrared spectrum and scanning electron microscope. The results showed that the tensile strength of the SAN/SA film with the mass ratio of 5:5 was the highest, and the difference between the film with the ratio of 4:6 was not significant (P>0.05), but was significantly higher than that of other films (P<0.05). The flexibility of film with SAN/SA mass ratio of 6:4 was significantly increased (P<0.05), the water vapor transmittance and solubility of this film were the lowest. Differential scanning calorimetry analysis showed that the heat resistance of the composite film was improved. According to the results of fourier transform infrared spectrum, hydrogen bond interaction existed between SAN and SA molecules, indicating good compatibility and synergistic effect between them. The microstructure showed that the network structure of the composite film was arranged more orderly and the pores of the film surface were smaller. The results showed that SAN had a good synergistic effect with sodium alginate, and the properties of SAN/SA composite film were significantly improved. As a newly approved natural polymer which can be used in the food field, the application prospect of SAN is broad.
More+
2021, 42(19): 261-266.
doi: 10.13386/j.issn1002-0306.2020110131
Abstract:
Based on the limited research of mineral content of infant formula, 12 kinds of mineral content from 170 batches of older infant formula were selected and determined. The results showed that all the mineral content from 170 batches of older infant formula satisfied the standard of 《GB 10767-2010 National food safety standard older infant and baby formula》. However, part of copper, iodine and selenium didn’t satisfied the standard of Regulation (EU) 2016/127. In the 170 batches, 12 minerals content were in the tolerable upper intake level of 《Reference intake of dietary nutrients for Chinese residents(2013)》, part of sodium, magnesium, iron, iodine, chlorine, selenium and manganese didn’t meet the recommended nutrient intakes. The research indicated that the insufficient of mineral content in older infant formula could affect the development of infant. It’s necessary to consider all factors in order to guide enterprises to production and meet the growth and development needs of older infant.
Based on the limited research of mineral content of infant formula, 12 kinds of mineral content from 170 batches of older infant formula were selected and determined. The results showed that all the mineral content from 170 batches of older infant formula satisfied the standard of 《GB 10767-2010 National food safety standard older infant and baby formula》. However, part of copper, iodine and selenium didn’t satisfied the standard of Regulation (EU) 2016/127. In the 170 batches, 12 minerals content were in the tolerable upper intake level of 《Reference intake of dietary nutrients for Chinese residents(2013)》, part of sodium, magnesium, iron, iodine, chlorine, selenium and manganese didn’t meet the recommended nutrient intakes. The research indicated that the insufficient of mineral content in older infant formula could affect the development of infant. It’s necessary to consider all factors in order to guide enterprises to production and meet the growth and development needs of older infant.
2021, 42(19): 267-274.
doi: 10.13386/j.issn1002-0306.2020110260
Abstract:
Moringa oleifera leaf tea were fermented by natural fermentation, yeast fermentation, Rhizopus fermentation and Aspergillus niger fermentation. Color indexs, sensory quality and chemical components of Moringa oleifera leaf tea samples in different fermentation stages were determined, and correlations among chemical components were analyzed. Results showed that the main chemical components and quality of Moringa oleifera leaf tea samples in different fermentation stages were converted obviously. When Moringa oleifera leaf tea was fermented for 16 days, its sensory quality had been improved, and the contents of soluble protein and caffeine increased, while the contents of polyphenol, flavonoid, polysaccharide and water extract decreased. The color indexes △E* value, a* value and b* value of soups of Moringa oleifera leaf tea fermented samples increased with the increase of pile-up times. The fourth pile-up sample of Moringa oleifera leaf tea fermented by Aspergillus niger had the best sensory quality, the contents of its polyphenol, flavonoid, soluble protein, polysaccharide, caffeine and water extract were 13.48, 10.99, 16.46, 27.38, 2.39 and 342.70 mg/g, and the color indexes a* value, △E* value and b* value of its soup were 15.66, 28.48 and 36.42, respectively. The contents of water extracts (Y) of different fermented samples of Moringa oleifera leaf tea were significantly positively correlated with the contents of polyphenol (X1), soluble protein (X3) and polysaccharide (X4), their correlation coefficients were 0.8821, 0.7598 and 0.7240, respectively, and the regression equation was Y=15.8337+0.6793X1+0.2360X3+0.0897X4. The results of this study can provide the references for exploitation of Moringa oleifera leaf fermentation tea and utilization of this resource.
Moringa oleifera leaf tea were fermented by natural fermentation, yeast fermentation, Rhizopus fermentation and Aspergillus niger fermentation. Color indexs, sensory quality and chemical components of Moringa oleifera leaf tea samples in different fermentation stages were determined, and correlations among chemical components were analyzed. Results showed that the main chemical components and quality of Moringa oleifera leaf tea samples in different fermentation stages were converted obviously. When Moringa oleifera leaf tea was fermented for 16 days, its sensory quality had been improved, and the contents of soluble protein and caffeine increased, while the contents of polyphenol, flavonoid, polysaccharide and water extract decreased. The color indexes △E* value, a* value and b* value of soups of Moringa oleifera leaf tea fermented samples increased with the increase of pile-up times. The fourth pile-up sample of Moringa oleifera leaf tea fermented by Aspergillus niger had the best sensory quality, the contents of its polyphenol, flavonoid, soluble protein, polysaccharide, caffeine and water extract were 13.48, 10.99, 16.46, 27.38, 2.39 and 342.70 mg/g, and the color indexes a* value, △E* value and b* value of its soup were 15.66, 28.48 and 36.42, respectively. The contents of water extracts (Y) of different fermented samples of Moringa oleifera leaf tea were significantly positively correlated with the contents of polyphenol (X1), soluble protein (X3) and polysaccharide (X4), their correlation coefficients were 0.8821, 0.7598 and 0.7240, respectively, and the regression equation was Y=15.8337+0.6793X1+0.2360X3+0.0897X4. The results of this study can provide the references for exploitation of Moringa oleifera leaf fermentation tea and utilization of this resource.
2021, 42(19): 275-282.
doi: 10.13386/j.issn1002-0306.2020120105
Abstract:
In order to achieve identification of different storage years of red wine, an electronic tongue identification method based on ensemble empirical modal decomposition(EEMD), whale optimization algorithm (WOA) and least square support vector machine (LSSVM) was proposed. The voltammetry electronic tongue was used to collect the "fingerprint" information of the aged red wine with four storage years, and then the ensemble empirical modal decomposition was used to carry out the original signal of the electronic tongue. The scale decomposition obtained a set of intrinsic mode functions, and finally obtained its singular spectral entropy and Hilbert marginal spectrum as feature data. Finally, the whale optimization algorithm was used to optimize the parameters of the least square support vector machine, and the analysis model of red wine storage age was established. The experimental results showed that the accuracy, precision, recall, F1-score and Kappa coefficient of EEMD-WOA-LSSVM model were 97.5%, 97.75%, 97.5%, 0.98 and 0.97, respectively, which had discrimination better performance for storage year of red wine compared with SVM, GA-LSSVM and PSO-LSSVM. This research can provide a technical reference and research approach of red wine storage year.
In order to achieve identification of different storage years of red wine, an electronic tongue identification method based on ensemble empirical modal decomposition(EEMD), whale optimization algorithm (WOA) and least square support vector machine (LSSVM) was proposed. The voltammetry electronic tongue was used to collect the "fingerprint" information of the aged red wine with four storage years, and then the ensemble empirical modal decomposition was used to carry out the original signal of the electronic tongue. The scale decomposition obtained a set of intrinsic mode functions, and finally obtained its singular spectral entropy and Hilbert marginal spectrum as feature data. Finally, the whale optimization algorithm was used to optimize the parameters of the least square support vector machine, and the analysis model of red wine storage age was established. The experimental results showed that the accuracy, precision, recall, F1-score and Kappa coefficient of EEMD-WOA-LSSVM model were 97.5%, 97.75%, 97.5%, 0.98 and 0.97, respectively, which had discrimination better performance for storage year of red wine compared with SVM, GA-LSSVM and PSO-LSSVM. This research can provide a technical reference and research approach of red wine storage year.
2021, 42(19): 283-290.
doi: 10.13386/j.issn1002-0306.2020120143
Abstract:
In order to establish organic acid quality control method including short chain volatile fatty acids for Baijiu distillery, the quantitative method of 18 organic acids was developed by HPLC. Each organic acid was separated effectively by flow rate and gradient optimization. The final optimized analytical conditions were listed as follows: the column was Atlanis T3 column(4.6 mm×250 mm, 5 μm), flow rate was 0.4 mL/min, gradient elution was adopted, column temperature was 30 ℃, detection wavelength was 210 nm, and sample loading volume was 10 μL. This method had a wide linear range, R2>0.989, as well as quantitative limits were from 0.280 to 3.138 mg/L, recovery rates were from 93.03% to 107.21%, relative standard deviations were less than 3.70%. The results of tracking the changes of the contents of organic acids in the ferment broth of rice-flavored liquor during its fermentation process showed that the content of each organic acid showed different changing trends during fermentation. Comparing with those of initial fermented mash, the contents of all the organic acids except citric acid, L-malic acid, fumaric acid increased in the fermented mash of 12th day. L-lactic acid, acetic acid, isobutyric acid, isovaleric acid and succinic acid were the five most abundant organic acids in fermented mash of 12th day, the amounts of them were all more than 10% of total organic acid. In addition to the even increasing of the total organic acid amount, the distributions of organic acids in different stages of fermentation were significantly different. It was suggested that the composition of rice flavor organic acids could be effectively controlled by adjusting the fermentation duration. This method is an effective analysis method for the acidity quality control of rice-flavored liquor production.
In order to establish organic acid quality control method including short chain volatile fatty acids for Baijiu distillery, the quantitative method of 18 organic acids was developed by HPLC. Each organic acid was separated effectively by flow rate and gradient optimization. The final optimized analytical conditions were listed as follows: the column was Atlanis T3 column(4.6 mm×250 mm, 5 μm), flow rate was 0.4 mL/min, gradient elution was adopted, column temperature was 30 ℃, detection wavelength was 210 nm, and sample loading volume was 10 μL. This method had a wide linear range, R2>0.989, as well as quantitative limits were from 0.280 to 3.138 mg/L, recovery rates were from 93.03% to 107.21%, relative standard deviations were less than 3.70%. The results of tracking the changes of the contents of organic acids in the ferment broth of rice-flavored liquor during its fermentation process showed that the content of each organic acid showed different changing trends during fermentation. Comparing with those of initial fermented mash, the contents of all the organic acids except citric acid, L-malic acid, fumaric acid increased in the fermented mash of 12th day. L-lactic acid, acetic acid, isobutyric acid, isovaleric acid and succinic acid were the five most abundant organic acids in fermented mash of 12th day, the amounts of them were all more than 10% of total organic acid. In addition to the even increasing of the total organic acid amount, the distributions of organic acids in different stages of fermentation were significantly different. It was suggested that the composition of rice flavor organic acids could be effectively controlled by adjusting the fermentation duration. This method is an effective analysis method for the acidity quality control of rice-flavored liquor production.
2021, 42(19): 291-297.
doi: 10.13386/j.issn1002-0306.2020120169
Abstract:
In this experiment, Staphylococcus aureus was selected as the model target, and a pair of aptamers were used as the recognition molecules. An aptamer-based lateral flow test strip (ABLF) was prepared for the qualitative detection of Staphylococcus aureus based on the sandwich-type model and principle of lateral flow chromato gram. Several crucial parameters were investigated, including the NaCl concentrations, aptamer concentrations, the loaded amounts of gold nanoparticle-aptamer conjugates and capture probe to obtain the best preparation conditions for ABLF. The sensitivity and specificity of the ABLF were tested under optimized conditions. Finally, the ABLF approach was applied for qualitative detection of Staphylococcus aureu in 116 food samples, and was validated using sandard method (GB 4789.10-2016). The results showed that the optimal conditions for preparing ABLF were as follows: NaCl concentration 80 mmol/L, aptamer concentration 1 µmol/L, dilution volume ratio of gold nanoparticles-aptamer 1:2, capture probe concentration 25 μmol/L. Under the optimal experimental conditions, the visual limit of detection of the strip for Staphylococcus aureus were 2×103 CFU/mL. The assay can be completed within 5 min, and no significant cross-reactivity with other foodborne pathogens such as Salmonella typhimurium, Listeria monocytogenes, Escherichia coli, Bntorobater sakazakii, Shigella dysenteriae were observed. The test results obtained by the proposed method were found to be in consistency with those obtained from GB sandard method. The method developed was simple, rapid, accurate and inexpensive, which could be a potential screening tool for the qualitative detection of Staphylococcus aureus in food samples.
In this experiment, Staphylococcus aureus was selected as the model target, and a pair of aptamers were used as the recognition molecules. An aptamer-based lateral flow test strip (ABLF) was prepared for the qualitative detection of Staphylococcus aureus based on the sandwich-type model and principle of lateral flow chromato gram. Several crucial parameters were investigated, including the NaCl concentrations, aptamer concentrations, the loaded amounts of gold nanoparticle-aptamer conjugates and capture probe to obtain the best preparation conditions for ABLF. The sensitivity and specificity of the ABLF were tested under optimized conditions. Finally, the ABLF approach was applied for qualitative detection of Staphylococcus aureu in 116 food samples, and was validated using sandard method (GB 4789.10-2016). The results showed that the optimal conditions for preparing ABLF were as follows: NaCl concentration 80 mmol/L, aptamer concentration 1 µmol/L, dilution volume ratio of gold nanoparticles-aptamer 1:2, capture probe concentration 25 μmol/L. Under the optimal experimental conditions, the visual limit of detection of the strip for Staphylococcus aureus were 2×103 CFU/mL. The assay can be completed within 5 min, and no significant cross-reactivity with other foodborne pathogens such as Salmonella typhimurium, Listeria monocytogenes, Escherichia coli, Bntorobater sakazakii, Shigella dysenteriae were observed. The test results obtained by the proposed method were found to be in consistency with those obtained from GB sandard method. The method developed was simple, rapid, accurate and inexpensive, which could be a potential screening tool for the qualitative detection of Staphylococcus aureus in food samples.
Determination of 7 Nucleosides Contents in Cortex of Morus australis, Morus cathayana and Morus alba
2021, 42(19): 298-306.
doi: 10.13386/j.issn1002-0306.2021010190
Abstract:
Objective: Seven nucleosides, including adenine, adenosine, cytidine, hypoxanthine, guanosine, uracil and 2'- deoxyadenosine, were determined and analyzed by HPLC in the root bark of Morus australis, Morus cathayana and Morus alba from different areas, so as to provide reference for formulating quality standards. Methods: A venusil MP C18 (5 μm, 250 mm × 4.6 mm) column was used. The mobile phases of methanol and water were used for gradient elution. Detection wavelength was 260 nm. The flow rate was 1.0 mL/min. The column temperature was 30 ℃. Results: There was a good linear relationship between the seven nucleosides in their respective concentration ranges (r≥0.9998). The average recoveries were 97.49%~101.45% with RSD ≤3%. There were significant differences in the contents of seven nucleosides in the root bark of Morus australis, Morus cathayana and Morus alba from different producing areas. The contents of uracil and hypoxanthine in the root bark of Morus alba and Morus australis were higher, but the contents of hypoxanthine in different varieties were different, and the content of cytidine was the lowest. The content of guanosine and adenine in root bark of Morus alba was higher than that of 2'- deoxyadenosine. The nucleoside composition of Morus australis and Morus cathayana was slightly lower than that of Morus alba. The results of independent sample t-test showed that there was no significant difference among the seven nucleosides in the root bark of Morus australis, Morus cathayana and Morus alba (P>0.05) and its nucleoside components had certain isotropy. The results of principal component analysis and cluster analysis showed that Morus australis, Morus cathayana and Morus alba could not be distinguished according to the difference of nucleoside content, indicating that Australis Cortex Mori from Morus australis, Morus cathayana could be used as the substitute of Cortex Mori. Conclusion: There is no significant difference in nucleoside contents among the root bark of Morus australis, Morus cathayana and Morus alba. This study provides a scientific basis for the study on the quality equivalence of Morus australis, Morus cathayana and Morus alba.
Objective: Seven nucleosides, including adenine, adenosine, cytidine, hypoxanthine, guanosine, uracil and 2'- deoxyadenosine, were determined and analyzed by HPLC in the root bark of Morus australis, Morus cathayana and Morus alba from different areas, so as to provide reference for formulating quality standards. Methods: A venusil MP C18 (5 μm, 250 mm × 4.6 mm) column was used. The mobile phases of methanol and water were used for gradient elution. Detection wavelength was 260 nm. The flow rate was 1.0 mL/min. The column temperature was 30 ℃. Results: There was a good linear relationship between the seven nucleosides in their respective concentration ranges (r≥0.9998). The average recoveries were 97.49%~101.45% with RSD ≤3%. There were significant differences in the contents of seven nucleosides in the root bark of Morus australis, Morus cathayana and Morus alba from different producing areas. The contents of uracil and hypoxanthine in the root bark of Morus alba and Morus australis were higher, but the contents of hypoxanthine in different varieties were different, and the content of cytidine was the lowest. The content of guanosine and adenine in root bark of Morus alba was higher than that of 2'- deoxyadenosine. The nucleoside composition of Morus australis and Morus cathayana was slightly lower than that of Morus alba. The results of independent sample t-test showed that there was no significant difference among the seven nucleosides in the root bark of Morus australis, Morus cathayana and Morus alba (P>0.05) and its nucleoside components had certain isotropy. The results of principal component analysis and cluster analysis showed that Morus australis, Morus cathayana and Morus alba could not be distinguished according to the difference of nucleoside content, indicating that Australis Cortex Mori from Morus australis, Morus cathayana could be used as the substitute of Cortex Mori. Conclusion: There is no significant difference in nucleoside contents among the root bark of Morus australis, Morus cathayana and Morus alba. This study provides a scientific basis for the study on the quality equivalence of Morus australis, Morus cathayana and Morus alba.
2021, 42(19): 307-313.
doi: 10.13386/j.issn1002-0306.2021030328
Abstract:
To find out the kinds of volatile flavor compounds in giant salamander head soup and evaluate the quality of the soup, the volatile flavor fingerprints of Andrias davidianus soup with different stewing time (30, 60, 90, 120 and 150 min) were investigated by gas chromatography ion migration chromatography (GC-IMS). The results showed that: GC-IMS technology could achieve better separation of volatile flavor compounds of salamander head soup at different stewing time. A total of 35 volatile flavor compounds were identified in different stewing time, including 17 aldehydes, 8 esters, 4 ketones, 4 alcohols, 1 acid and 1 pyrazine. With the extension of stewing time (30~150 min), the concentrations of propanal, 3-methylbutan-1-ol, ethanol, heptanal, 2-heptanone, ethyl acetate, nonanal and octanal decreased significantly, while the concentrations of n-hexanol, butanal, ethyl 2-methylbutyrate, hexyl propanoate, 2-butanone, pentanal, 3-methylbutanal, benzaldehyde, ethyl propanoate and ethyl butyrate increased gradually. In this study, the volatile flavor fingerprints of salamander head soup during stewing were established, and the volatile flavor profiles of salamander head soup at different stewing time were visualized, which provided a reference for quality control, quality evaluation and standard formulation of salamander head soup in the future.
To find out the kinds of volatile flavor compounds in giant salamander head soup and evaluate the quality of the soup, the volatile flavor fingerprints of Andrias davidianus soup with different stewing time (30, 60, 90, 120 and 150 min) were investigated by gas chromatography ion migration chromatography (GC-IMS). The results showed that: GC-IMS technology could achieve better separation of volatile flavor compounds of salamander head soup at different stewing time. A total of 35 volatile flavor compounds were identified in different stewing time, including 17 aldehydes, 8 esters, 4 ketones, 4 alcohols, 1 acid and 1 pyrazine. With the extension of stewing time (30~150 min), the concentrations of propanal, 3-methylbutan-1-ol, ethanol, heptanal, 2-heptanone, ethyl acetate, nonanal and octanal decreased significantly, while the concentrations of n-hexanol, butanal, ethyl 2-methylbutyrate, hexyl propanoate, 2-butanone, pentanal, 3-methylbutanal, benzaldehyde, ethyl propanoate and ethyl butyrate increased gradually. In this study, the volatile flavor fingerprints of salamander head soup during stewing were established, and the volatile flavor profiles of salamander head soup at different stewing time were visualized, which provided a reference for quality control, quality evaluation and standard formulation of salamander head soup in the future.
More+
2021, 42(19): 314-320.
doi: 10.13386/j.issn1002-0306.2020070312
Abstract:
To explore the effect of lactobionic acid compound preservative on the fresh-keeping effect and quality of chilled meat, lactobionic acid was used as the main raw material and uncoated chilled meat was used as control group, chitosan and tea polyphenols were combined to make the compound preservative. The effects of the compound on the quality of chilled meat were investigated by measuring the sensory, physical and chemical and microbial indexes of chilled meat. The results showed that the logarithm of the total number of chilled meat, the TVB-N value, the TBARs value , and the juice loss rate after treatment with the lactobionic acid compound preservative were significantly lower than those of the control group (P<0.05), and the hardness, elasticity and sensory scoring values were significantly higher than those of the control group (P<0.05). The shelf life of chilled fresh meat could be extended to 9 d after the compound fresh-keeping treatment. Lactobionic acid compound preservative can extend the shelf life of chilled meat, and improve the quality deterioration during refrigeration.
To explore the effect of lactobionic acid compound preservative on the fresh-keeping effect and quality of chilled meat, lactobionic acid was used as the main raw material and uncoated chilled meat was used as control group, chitosan and tea polyphenols were combined to make the compound preservative. The effects of the compound on the quality of chilled meat were investigated by measuring the sensory, physical and chemical and microbial indexes of chilled meat. The results showed that the logarithm of the total number of chilled meat, the TVB-N value, the TBARs value , and the juice loss rate after treatment with the lactobionic acid compound preservative were significantly lower than those of the control group (P<0.05), and the hardness, elasticity and sensory scoring values were significantly higher than those of the control group (P<0.05). The shelf life of chilled fresh meat could be extended to 9 d after the compound fresh-keeping treatment. Lactobionic acid compound preservative can extend the shelf life of chilled meat, and improve the quality deterioration during refrigeration.
2021, 42(19): 321-328.
doi: 10.13386/j.issn1002-0306.2020090055
Abstract:
Objective: In order to explore the effect of 1-Methylcyclopropene (1-MCP) on the storage quality of Lonicera caerulea L., with a view to providing theoretical and practical basis for Lonicera caerulea L. storage and preservation technology. Methods: The experiment using the Lonicera caerulea L. variety “Lanjingling” as the test material, after harvesting, it was treated with a concentration of 1 µL/L 1-MCP for 24 h, and the effect of 1-MCP treatment on the storage quality, physiological changes and anti-oxidant effects of the fruits during storage at ice temperature (−0.5±0.3) ℃ was studied. Results: Compared with the control, 1-MCP treatment delayed the decrease of good fruit rate, frost coverage index and flavor index during storage. The hardness was 1.39 kg/cm2 at 60 days of storage, which was significantly higher than the hardness of CK group (0.95 kg/cm2) during the same period and maintained the organoleptic qualities and inherent texture of the fruit. In early storage, 1-MCP treatment such as ascorbic acid, anthocyanins, flavones and total phenol content was maintained at a high level, while suppressing respiration and MDA content of the fruits, the biologically active material was suppressed and the decrease of delaying the senescence of fruits. In terms of antioxidant properties, 1-MCP could effectively slow down the decrease of T-GSH, GSH, and GSSG content, while maintaining high GR and SOD activities in the early stage of storage, thereby achieving the ability to maintain the antioxidant capacity of the fruits. Conclude: 1-MCP can effectively maintain the quality of Lonicera caerulea L. during the postharvest storage period.
Objective: In order to explore the effect of 1-Methylcyclopropene (1-MCP) on the storage quality of Lonicera caerulea L., with a view to providing theoretical and practical basis for Lonicera caerulea L. storage and preservation technology. Methods: The experiment using the Lonicera caerulea L. variety “Lanjingling” as the test material, after harvesting, it was treated with a concentration of 1 µL/L 1-MCP for 24 h, and the effect of 1-MCP treatment on the storage quality, physiological changes and anti-oxidant effects of the fruits during storage at ice temperature (−0.5±0.3) ℃ was studied. Results: Compared with the control, 1-MCP treatment delayed the decrease of good fruit rate, frost coverage index and flavor index during storage. The hardness was 1.39 kg/cm2 at 60 days of storage, which was significantly higher than the hardness of CK group (0.95 kg/cm2) during the same period and maintained the organoleptic qualities and inherent texture of the fruit. In early storage, 1-MCP treatment such as ascorbic acid, anthocyanins, flavones and total phenol content was maintained at a high level, while suppressing respiration and MDA content of the fruits, the biologically active material was suppressed and the decrease of delaying the senescence of fruits. In terms of antioxidant properties, 1-MCP could effectively slow down the decrease of T-GSH, GSH, and GSSG content, while maintaining high GR and SOD activities in the early stage of storage, thereby achieving the ability to maintain the antioxidant capacity of the fruits. Conclude: 1-MCP can effectively maintain the quality of Lonicera caerulea L. during the postharvest storage period.
2021, 42(19): 329-335.
doi: 10.13386/j.issn1002-0306.2020110174
Abstract:
In this study, polypropylene (PP) with chemical resistance, heat resistance, high strength mechanical properties and high wear resistance processing properties was selected as the base material to blend with the biodegradable material PBAT resin with high moisture permeability. After mixing, selected the ratio of the best modification effect (PP80%/PBAT20%) to make PPT2 blend film, and carried out PPT2 vacuum packaging and PPT2 sealed packaging on Flammulina velutipes. By comparing the blank group without packaging, the market packaging group, the PPT2 sealing group and the PPT2 vacuum group, it was found that the unpackaged group wilted and rotted at the 3rd day and lost its edible value. The market packaging group had a decline in soluble solid content at 18 days and condensation and swelling on the packaging bag lost its edible value. PPT2 was sealed due to the unstable atmosphere control of the packaging group in the early stage, the soluble solid content appears to rise suddenly when breathing is strong. PPT2 vacuum packaging group Flammulina velutipes weight loss rate, Vc content change, and soluble solid content decreased relatively smoothly, and there was no phenomenon such as swelling and condensation, and wilting and rotting do not appear until 27 days of storage. It losed its edible value. The comparison was excellent. Therefore, the PPT2 blend film combined with vacuum packaging could effectively control the elongation of the stalk caused by the growth of Flammulina velutipes, thereby extending the shelf life.
In this study, polypropylene (PP) with chemical resistance, heat resistance, high strength mechanical properties and high wear resistance processing properties was selected as the base material to blend with the biodegradable material PBAT resin with high moisture permeability. After mixing, selected the ratio of the best modification effect (PP80%/PBAT20%) to make PPT2 blend film, and carried out PPT2 vacuum packaging and PPT2 sealed packaging on Flammulina velutipes. By comparing the blank group without packaging, the market packaging group, the PPT2 sealing group and the PPT2 vacuum group, it was found that the unpackaged group wilted and rotted at the 3rd day and lost its edible value. The market packaging group had a decline in soluble solid content at 18 days and condensation and swelling on the packaging bag lost its edible value. PPT2 was sealed due to the unstable atmosphere control of the packaging group in the early stage, the soluble solid content appears to rise suddenly when breathing is strong. PPT2 vacuum packaging group Flammulina velutipes weight loss rate, Vc content change, and soluble solid content decreased relatively smoothly, and there was no phenomenon such as swelling and condensation, and wilting and rotting do not appear until 27 days of storage. It losed its edible value. The comparison was excellent. Therefore, the PPT2 blend film combined with vacuum packaging could effectively control the elongation of the stalk caused by the growth of Flammulina velutipes, thereby extending the shelf life.
2021, 42(19): 336-341.
doi: 10.13386/j.issn1002-0306.2021010051
Abstract:
In this study, the best antibacterial method "US-NaClO-phytic acid" for fresh-cut lettuce after cleaning was selected from 8 methods included tap water, ultrasound (US), slightly acidic electrolyzed water (SAEW), US combined with SAEW, US combined with phytic acid, NaClO combined with phytic acid, US-NaClO-SAEW, and US-NaClO-phytic acid, and the quality indexes of fresh-cut lettuce treated by US-NaClO-phytic acid during storage were measured and sterile distilled water was used as a control. The antibacterial effect of US-NaClO-phytic acid on Escherichia coli O157:H7 (E.coli O157:H7) as well as on the storage quality of fresh-cut lettuce were investigated. The results showed that US-NaClO-phytic acid had the best antibacterial effect and the inhibitory rate reached 99.97%. On the 14th day of storage, fresh-cut lettuce treated by US-NaClO-phytic acid had the mass loss rate of 3.45%, the total color difference of 5.39, the Vc content of 2.93 mg/100 g, the chlorophyll content of 0.56 mg/g, and the moisture content of 90.54%, which were all better than those of the control group. Compared with the control group, the peroxidase and polyphenol oxidase activities were effectively inhibited, and the total phenolics content remained the higher level. Therefore, US-NaClO-phytic acid can improve the antibacterial effect on E.coli O157:H7 and the storage quality of fresh-cut lettuce. In conclusion, US-NaClO-phytic acid could effectively maintain the fresh-keeping effect of fresh-cut lettuce and prolong its shelf life.
In this study, the best antibacterial method "US-NaClO-phytic acid" for fresh-cut lettuce after cleaning was selected from 8 methods included tap water, ultrasound (US), slightly acidic electrolyzed water (SAEW), US combined with SAEW, US combined with phytic acid, NaClO combined with phytic acid, US-NaClO-SAEW, and US-NaClO-phytic acid, and the quality indexes of fresh-cut lettuce treated by US-NaClO-phytic acid during storage were measured and sterile distilled water was used as a control. The antibacterial effect of US-NaClO-phytic acid on Escherichia coli O157:H7 (E.coli O157:H7) as well as on the storage quality of fresh-cut lettuce were investigated. The results showed that US-NaClO-phytic acid had the best antibacterial effect and the inhibitory rate reached 99.97%. On the 14th day of storage, fresh-cut lettuce treated by US-NaClO-phytic acid had the mass loss rate of 3.45%, the total color difference of 5.39, the Vc content of 2.93 mg/100 g, the chlorophyll content of 0.56 mg/g, and the moisture content of 90.54%, which were all better than those of the control group. Compared with the control group, the peroxidase and polyphenol oxidase activities were effectively inhibited, and the total phenolics content remained the higher level. Therefore, US-NaClO-phytic acid can improve the antibacterial effect on E.coli O157:H7 and the storage quality of fresh-cut lettuce. In conclusion, US-NaClO-phytic acid could effectively maintain the fresh-keeping effect of fresh-cut lettuce and prolong its shelf life.
More+
2021, 42(19): 342-349.
doi: 10.13386/j.issn1002-0306.2020080011
Abstract:
In order to study the antioxidant effect of dietary fiber in long-lived people in Bemba, Guangxi, six-week-old healthy C57BL/6 mice were selected as study subjects. Seven kinds of dietary fiber (DF), which the most representative of longevity population in Bama, Guangxi, were selected, including banana, navel orange, pumpkin seedling, sweet potato leaf, water spinach, Ixeris sonchifolia and agrocybe chaxingu, and 10 feeding patterns were designed. Mice were fed with these 10 patterns for 4 weeks. The contents of malondialdehyde (MDA) and lipofuscin (Lip), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in serum and liver tissues of the tested mice were determined. The results showed that except for Ixeris sonchifolia dietary fiber, the addition of single dietary fiber had no significant effect on the weight gain of mice. In a certain range, the larger the addition of compound dietary fiber, the slower the weight gain rate of mice. Among them, the heart coefficients of mice in the 7.5% and 15% compound dietary fiber addition groups were increased by 7.22 % (P<0.05) and 6.92 % (P<0.05), respectively. The spleen coefficients of mice were increased by 10.00%, 15.00% by adding pumpkin seedling dietary fiber isolate and 30% composite dietary fiber isolate. The dietary fiber isolates in each group could effectively reduce the levels of MDA and lipofuscin Lip in serum and liver of mice , and improve the activities of SOD, GSH-Px and T-AOC in serum and liver of mice. Comprehensive analysis shows that adding compound dietary fiber to the diet of mice has stronger antioxidant stress and better antioxidant effect.
In order to study the antioxidant effect of dietary fiber in long-lived people in Bemba, Guangxi, six-week-old healthy C57BL/6 mice were selected as study subjects. Seven kinds of dietary fiber (DF), which the most representative of longevity population in Bama, Guangxi, were selected, including banana, navel orange, pumpkin seedling, sweet potato leaf, water spinach, Ixeris sonchifolia and agrocybe chaxingu, and 10 feeding patterns were designed. Mice were fed with these 10 patterns for 4 weeks. The contents of malondialdehyde (MDA) and lipofuscin (Lip), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in serum and liver tissues of the tested mice were determined. The results showed that except for Ixeris sonchifolia dietary fiber, the addition of single dietary fiber had no significant effect on the weight gain of mice. In a certain range, the larger the addition of compound dietary fiber, the slower the weight gain rate of mice. Among them, the heart coefficients of mice in the 7.5% and 15% compound dietary fiber addition groups were increased by 7.22 % (P<0.05) and 6.92 % (P<0.05), respectively. The spleen coefficients of mice were increased by 10.00%, 15.00% by adding pumpkin seedling dietary fiber isolate and 30% composite dietary fiber isolate. The dietary fiber isolates in each group could effectively reduce the levels of MDA and lipofuscin Lip in serum and liver of mice , and improve the activities of SOD, GSH-Px and T-AOC in serum and liver of mice. Comprehensive analysis shows that adding compound dietary fiber to the diet of mice has stronger antioxidant stress and better antioxidant effect.
2021, 42(19): 350-356.
doi: 10.13386/j.issn1002-0306.2020100020
Abstract:
In order to evaluate the ability of chitotriose guanidine hydrochloride to improve insulin resistance, this study used high-sugar and high-fat to induce HepG2 cells to establish an insulin resistance cell model, and intervened the cell model with different concentrations and guanidine substituted chitotriose guanidine hydrochloride. Then, indicators such as glucose uptake of model cells were detected. The results showed that 300 µg/mL and 600 µg/mL chitotriose guanidine hydrochloride could significantly increase the glucose uptake of the model cells (P<0.05), while 600 µg/mL displayed a superior effect. Chitotriose guanidine hydrochloride with different guanidine substitution degrees could significantly increase the glucose uptake of model cells (P<0.05), while 78% guanidine substitution had the best effect. Chitotriose guanidine hydrochloride with 600 µg/mL and 78% guanidine substitution degree significantly increased the glucose uptake of the model cells and glycogen content (P<0.05), while reducing the iNOS activity in the cells (P<0.05), and exhibiting a beneficial effect on the insulin-resistant cell model, which provides a theoretical basis for the development of new functional foods that have a good effect in type 2 diabetes intervention.
In order to evaluate the ability of chitotriose guanidine hydrochloride to improve insulin resistance, this study used high-sugar and high-fat to induce HepG2 cells to establish an insulin resistance cell model, and intervened the cell model with different concentrations and guanidine substituted chitotriose guanidine hydrochloride. Then, indicators such as glucose uptake of model cells were detected. The results showed that 300 µg/mL and 600 µg/mL chitotriose guanidine hydrochloride could significantly increase the glucose uptake of the model cells (P<0.05), while 600 µg/mL displayed a superior effect. Chitotriose guanidine hydrochloride with different guanidine substitution degrees could significantly increase the glucose uptake of model cells (P<0.05), while 78% guanidine substitution had the best effect. Chitotriose guanidine hydrochloride with 600 µg/mL and 78% guanidine substitution degree significantly increased the glucose uptake of the model cells and glycogen content (P<0.05), while reducing the iNOS activity in the cells (P<0.05), and exhibiting a beneficial effect on the insulin-resistant cell model, which provides a theoretical basis for the development of new functional foods that have a good effect in type 2 diabetes intervention.
2021, 42(19): 357-362.
doi: 10.13386/j.issn1002-0306.2020100085
Abstract:
Objective: To investigate the effect and mechanism of multiple composite resistant starch (RS) on glucose and lipid metabolism in high-sugar and high-fat model mice. Methods: The mice were divided into six groups, namely the normal control group, the high-sugar and high-fat model group, the positive control group and multiple composite RS low dose group, multiple composite RS middle dose group, multiple composite RS high dose group. The effects of multiple complex RS on body mass, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL-C), liver glycogen in high-glycemic and high-fat mice and the influence of short chain fatty acids (SCFAs) in intestinal contents. Results: RS high dose group compared with the mice in the model control group, the body mass, blood glucose, TC, and TG in the serum of mice in the multiple composite RS group were significantly decreased by 9.23%, 59.71%, 31.22%, and 36.72%, respectively, and HDL-C was significantly increased by 58.93%; the content of liver glycogen was positively correlated with the dose of multiple composite RS, and the content of liver glycogen increased significantly by 207.86%. The contents of acetic acid, propionic acid and butyric acid in the intestines increased significantly. Conclusion: The multiple compound RS can reduce the blood sugar level of high-sugar and high-fat model mice, increase the content of acetic acid, propionic acid and butyric acid in the intestine.
Objective: To investigate the effect and mechanism of multiple composite resistant starch (RS) on glucose and lipid metabolism in high-sugar and high-fat model mice. Methods: The mice were divided into six groups, namely the normal control group, the high-sugar and high-fat model group, the positive control group and multiple composite RS low dose group, multiple composite RS middle dose group, multiple composite RS high dose group. The effects of multiple complex RS on body mass, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL-C), liver glycogen in high-glycemic and high-fat mice and the influence of short chain fatty acids (SCFAs) in intestinal contents. Results: RS high dose group compared with the mice in the model control group, the body mass, blood glucose, TC, and TG in the serum of mice in the multiple composite RS group were significantly decreased by 9.23%, 59.71%, 31.22%, and 36.72%, respectively, and HDL-C was significantly increased by 58.93%; the content of liver glycogen was positively correlated with the dose of multiple composite RS, and the content of liver glycogen increased significantly by 207.86%. The contents of acetic acid, propionic acid and butyric acid in the intestines increased significantly. Conclusion: The multiple compound RS can reduce the blood sugar level of high-sugar and high-fat model mice, increase the content of acetic acid, propionic acid and butyric acid in the intestine.
2021, 42(19): 363-368.
doi: 10.13386/j.issn1002-0306.2020110181
Abstract:
This study investigated the effects of rice bran protein on lipid metabolism and its mechanism in rats fed with high-cholesterol diet. The experiment designed 4 groups including casein group (CAS, control), rice bran protein group(RBP), brown rice protein group (BRP) and rice protein group(WRP). The rats were fed with high-cholesterol diet supplemented with 20% casein, 15% casein+5% rice bran protein, 15% casein+5% brown rice protein and 15% casein+5% rice protein for 3 weeks. The levels of total cholesterol (TC) and contents of triglyceride (TG) in serum, and TC, TG and total lipid in liver of rats were measured. The feces were collected for 3 days before the animals were sacrificed, and the excretion of total bile acids and neutral sterols were determined. The micellar solubility of cholesterol with CAS, RBP, BRP and WRP, and the abilities of different concentrations CAS and RBP to bind with bile acid were determined by simulating human gastrointestinal environment in vitro. The results showed that compared with casein and other protein groups, rice bran protein significantly reduced serum TC (P<0.05) and atherosclerotic index (P<0.05); liver TC level was significantly reduced (P<0.05) and the total bile acid excretion in feces was significantly increased (P<0.05). The in vitro experiments showed that rice bran protein could bound to bile acids and significantly inhibited the solubility of cholesterol micelles (P<0.05). To sum up, rice bran protein bound to bile acids in vivo to inhibit its absorption in the intestines and increase its excretion in feces, and finally achieved the effects of reducing serum lipids.
This study investigated the effects of rice bran protein on lipid metabolism and its mechanism in rats fed with high-cholesterol diet. The experiment designed 4 groups including casein group (CAS, control), rice bran protein group(RBP), brown rice protein group (BRP) and rice protein group(WRP). The rats were fed with high-cholesterol diet supplemented with 20% casein, 15% casein+5% rice bran protein, 15% casein+5% brown rice protein and 15% casein+5% rice protein for 3 weeks. The levels of total cholesterol (TC) and contents of triglyceride (TG) in serum, and TC, TG and total lipid in liver of rats were measured. The feces were collected for 3 days before the animals were sacrificed, and the excretion of total bile acids and neutral sterols were determined. The micellar solubility of cholesterol with CAS, RBP, BRP and WRP, and the abilities of different concentrations CAS and RBP to bind with bile acid were determined by simulating human gastrointestinal environment in vitro. The results showed that compared with casein and other protein groups, rice bran protein significantly reduced serum TC (P<0.05) and atherosclerotic index (P<0.05); liver TC level was significantly reduced (P<0.05) and the total bile acid excretion in feces was significantly increased (P<0.05). The in vitro experiments showed that rice bran protein could bound to bile acids and significantly inhibited the solubility of cholesterol micelles (P<0.05). To sum up, rice bran protein bound to bile acids in vivo to inhibit its absorption in the intestines and increase its excretion in feces, and finally achieved the effects of reducing serum lipids.
2021, 42(19): 369-375.
doi: 10.13386/j.issn1002-0306.2020110238
Abstract:
Objective: To study the effects of three kinds of animal fats on gastric mucosa damage induced by ethanol in rats. Methods: Low (500 mg/kg) and high doses (850 mg/kg) of deer oil, butter and lard were given to rats by gavage for 30 days. Except for the normal group, rats in the other groups were given 1.0 mL of absolute ethanol per rat. One hour later, blood was taken from anesthesia, and gastric tissue was taken. Morphological observation, histopathological examination and the determination of acute injury indexes were performed on the gastric mucosa of rats. Detect the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in serum of rats in each group. The ELISA method was used to determine the serum levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and RT-PCR was used to detect erythropoietin (EPO) and erythropoietin receptor (EPOR) mRNA expression level. Results: Compared with the model group, the weight of rats in each administration group did not change significantly in each period. The stomach weight/body mass of the rats in the deer oil pretreatment group was extremely significantly reduced(P<0.001), and the gastric mucosal surface had fewer bleeding bands and thinner bleeding bands. The cells were arranged tightly and orderly, the inflammatory infiltration was reduced, the gastric mucosal congestion area and the injury score index were extremely significantly redu(P<0.001)ced, which could significantly increase the activity of GSH-Px, SOD activity(P<0.01) and significantly reduced the level of MDA(P<0.05), thereby improving the body's antioxidant capacity to protect the stomach. In mucosa, deer oil highly significantly reduced the levels of inflammatory factors TNF-α and IL-6 in the serum, could regulate the inflammatory factors produced by the damage of ethanol to the gastric mucosa, and reduced the mRNA expression of EPO and EPOR; rats in the butter pretreatment group, there were many slender bleeding bands on the surface of the gastric mucosa, the color was slightly darker, the cell arrangement was more orderly, the gastric mucosal congestion area and the injury score index were reduced, which could significantly increase the SOD activity(P<0.001) and reduce the MDA level to enhance the antioxidant capacity and protected the gastric mucosa; In the lard pretreatment group, there were many wide bleeding bands on the gastric mucosa surface, which were darker in color, and had no obvious effect on acute gastric mucosal injury. Conclusion: The protective effects of three animal fats on acute gastric mucosal injury are in order: deer oil>butter>lard. Deer oil has a significant protective effect on acute gastric mucosal injury in rats. The protective effect of butter is weak, while lard has no obvious protective effect.
Objective: To study the effects of three kinds of animal fats on gastric mucosa damage induced by ethanol in rats. Methods: Low (500 mg/kg) and high doses (850 mg/kg) of deer oil, butter and lard were given to rats by gavage for 30 days. Except for the normal group, rats in the other groups were given 1.0 mL of absolute ethanol per rat. One hour later, blood was taken from anesthesia, and gastric tissue was taken. Morphological observation, histopathological examination and the determination of acute injury indexes were performed on the gastric mucosa of rats. Detect the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in serum of rats in each group. The ELISA method was used to determine the serum levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and RT-PCR was used to detect erythropoietin (EPO) and erythropoietin receptor (EPOR) mRNA expression level. Results: Compared with the model group, the weight of rats in each administration group did not change significantly in each period. The stomach weight/body mass of the rats in the deer oil pretreatment group was extremely significantly reduced(P<0.001), and the gastric mucosal surface had fewer bleeding bands and thinner bleeding bands. The cells were arranged tightly and orderly, the inflammatory infiltration was reduced, the gastric mucosal congestion area and the injury score index were extremely significantly redu(P<0.001)ced, which could significantly increase the activity of GSH-Px, SOD activity(P<0.01) and significantly reduced the level of MDA(P<0.05), thereby improving the body's antioxidant capacity to protect the stomach. In mucosa, deer oil highly significantly reduced the levels of inflammatory factors TNF-α and IL-6 in the serum, could regulate the inflammatory factors produced by the damage of ethanol to the gastric mucosa, and reduced the mRNA expression of EPO and EPOR; rats in the butter pretreatment group, there were many slender bleeding bands on the surface of the gastric mucosa, the color was slightly darker, the cell arrangement was more orderly, the gastric mucosal congestion area and the injury score index were reduced, which could significantly increase the SOD activity(P<0.001) and reduce the MDA level to enhance the antioxidant capacity and protected the gastric mucosa; In the lard pretreatment group, there were many wide bleeding bands on the gastric mucosa surface, which were darker in color, and had no obvious effect on acute gastric mucosal injury. Conclusion: The protective effects of three animal fats on acute gastric mucosal injury are in order: deer oil>butter>lard. Deer oil has a significant protective effect on acute gastric mucosal injury in rats. The protective effect of butter is weak, while lard has no obvious protective effect.
2021, 42(19): 376-382.
doi: 10.13386/j.issn1002-0306.2021010168
Abstract:
Objective: To investigate the antioxidant activity of total flavonoids from paper mulberry fruits in vitro and its effect on brain damage induced by CCl4 in mice. Method: In order to study the antioxidant activity of total flavonoids from paper mulberry fruits in vitro, a biofilm experiment system with hydrogen peroxide (H2O2) inducing erythrocyte hemolysis, lipid peroxidation of liver and brain homogenate, and Fe2+-Vc inducing swelling of liver mitochondria were established. Meanwhile, a CCl4-induced oxidative damage model was established. The in vivo study was performed on 60 KM mice divided into six groups: blank group, model group, positive control group (silymarin, 0.2 g/kg) and total flavonoids groups (0.15, 0.3, 0.6 g/kg). The corresponding dose of drugs was given by intragastric administration every day, and the CCl4 peanut oil solution (1:1, V:V) was injected intraperitoneally (2 mL/kg) every other day. The blank group was given the same volume of solvent (peanut oil) for 14 days. The contents of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-PX) and catalase (CAT) were determined and the pathological sections of hippocampus were observed to evaluate the antioxidant activity of total flavonoids in vivo. Result: The inhibitory effect of total flavonoids from paper mulberry fruits on erythrocytic hemolysis, lipid peroxidation of liver and brain homogenate and swelling of liver mitochondria increased with the increase of concentration, and its total antioxidant capacity also increased with the increase of concentration in vitro. In the CCl4 brain injury model, the total flavonoids could significantly increase the SOD, GSH-PX, CAT activity and GSH levels (P<0.05) in the brain tissues of mice, and significantly reduce the MDA level (P<0.05) in a dose-dependent manner, while improving the pathological changed of hippocampal neurons. Conclusion: The total flavonoids from paper mulberry fruits have strong antioxidant activity in vitro, and show a good protective effect on CCl4 induced oxidative injury in mice brain tissue, have good antioxidant capacity in vivo.
Objective: To investigate the antioxidant activity of total flavonoids from paper mulberry fruits in vitro and its effect on brain damage induced by CCl4 in mice. Method: In order to study the antioxidant activity of total flavonoids from paper mulberry fruits in vitro, a biofilm experiment system with hydrogen peroxide (H2O2) inducing erythrocyte hemolysis, lipid peroxidation of liver and brain homogenate, and Fe2+-Vc inducing swelling of liver mitochondria were established. Meanwhile, a CCl4-induced oxidative damage model was established. The in vivo study was performed on 60 KM mice divided into six groups: blank group, model group, positive control group (silymarin, 0.2 g/kg) and total flavonoids groups (0.15, 0.3, 0.6 g/kg). The corresponding dose of drugs was given by intragastric administration every day, and the CCl4 peanut oil solution (1:1, V:V) was injected intraperitoneally (2 mL/kg) every other day. The blank group was given the same volume of solvent (peanut oil) for 14 days. The contents of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-PX) and catalase (CAT) were determined and the pathological sections of hippocampus were observed to evaluate the antioxidant activity of total flavonoids in vivo. Result: The inhibitory effect of total flavonoids from paper mulberry fruits on erythrocytic hemolysis, lipid peroxidation of liver and brain homogenate and swelling of liver mitochondria increased with the increase of concentration, and its total antioxidant capacity also increased with the increase of concentration in vitro. In the CCl4 brain injury model, the total flavonoids could significantly increase the SOD, GSH-PX, CAT activity and GSH levels (P<0.05) in the brain tissues of mice, and significantly reduce the MDA level (P<0.05) in a dose-dependent manner, while improving the pathological changed of hippocampal neurons. Conclusion: The total flavonoids from paper mulberry fruits have strong antioxidant activity in vitro, and show a good protective effect on CCl4 induced oxidative injury in mice brain tissue, have good antioxidant capacity in vivo.
More+
2021, 42(19): 383-394.
doi: 10.13386/j.issn1002-0306.2020070392
Abstract:
Antagonistic microorganisms have the advantages of natural, eco-friendly, safety and efficiency, which have been focused by researches on the research and application of fresh fruits and vegetables. Antagonistic microorganisms can reduce the post-harvest decay loss of fruits and vegetables, and have been developed as various biological agents for industries. This paper reviewed the mechanism of action, screening methods and research of antagonistic microorganisms of fruits and vegetables in recent years, and summarized the control and prevention of antagonistic microorganisms in fruits and vegetables, meanwhile, the existing problems and prospects of antagonists were analyzed in this review.
Antagonistic microorganisms have the advantages of natural, eco-friendly, safety and efficiency, which have been focused by researches on the research and application of fresh fruits and vegetables. Antagonistic microorganisms can reduce the post-harvest decay loss of fruits and vegetables, and have been developed as various biological agents for industries. This paper reviewed the mechanism of action, screening methods and research of antagonistic microorganisms of fruits and vegetables in recent years, and summarized the control and prevention of antagonistic microorganisms in fruits and vegetables, meanwhile, the existing problems and prospects of antagonists were analyzed in this review.
2021, 42(19): 395-402.
doi: 10.13386/j.issn1002-0306.2020080026
Abstract:
Cow milk is the best alternative to breast milk for infants and young children with rich nutrient. Most infant formula isproduced based on cow milk. In order to reduce milk protein allergens and minimize nutritional loss, non-thermal processing techniques is used. This paper introduce the structure and epitopes of major allergens in cow milk and summarizedthe research progress of hypo- or non-allergenic infant formula on the market. The effect of non-thermal processing techniques including high pressure, microwave, fermentation and its combination with enzymolysis on the allergenicity of milk protein is mainly discussed, moreover, its application in hypo- or non-allergenic infant formula is concluded, and its future development is prospected. This paper aim to provide theoretical support for the development and preparation of milk based infant formula with nutrition, palatability and low allergenicity.
Cow milk is the best alternative to breast milk for infants and young children with rich nutrient. Most infant formula isproduced based on cow milk. In order to reduce milk protein allergens and minimize nutritional loss, non-thermal processing techniques is used. This paper introduce the structure and epitopes of major allergens in cow milk and summarizedthe research progress of hypo- or non-allergenic infant formula on the market. The effect of non-thermal processing techniques including high pressure, microwave, fermentation and its combination with enzymolysis on the allergenicity of milk protein is mainly discussed, moreover, its application in hypo- or non-allergenic infant formula is concluded, and its future development is prospected. This paper aim to provide theoretical support for the development and preparation of milk based infant formula with nutrition, palatability and low allergenicity.
2021, 42(19): 403-410.
doi: 10.13386/j.issn1002-0306.2020080035
Abstract:
Milk safety problems occur frequently, in order to assure the food safety and avoid health risks to consumers, rapid and non-invasive analytical procedures need to be proposed for detection of dairy industry. Surface-enhanced Raman Spectroscopy (SERS) is a fast and sensitive molecular fingerprint technology. Because of its easy operation, non-invasive, fast and unaffected by water, it is widely used in the detection of dairy products. The stability and reproducibility of SERS signals mainly depend on the preparation of SERS substrates. This article reviews the preparation methods of SERS substrates in milk testing in recent years, the most study of SERS substrate materials are high-cost precious metal materials, which leads to some limitations in the application of precious metal substrates. Therefore, SERS substrates of new materials are one of the prospects of surface-enhanced Raman spectroscopy research. In addition, the currently reported SERS substrates used in milk detection are only part of the many pollutants in milk, adulterants such as formaldehyde, hydrogen peroxide, dichromic acid and salicylic acid have not been reported.
Milk safety problems occur frequently, in order to assure the food safety and avoid health risks to consumers, rapid and non-invasive analytical procedures need to be proposed for detection of dairy industry. Surface-enhanced Raman Spectroscopy (SERS) is a fast and sensitive molecular fingerprint technology. Because of its easy operation, non-invasive, fast and unaffected by water, it is widely used in the detection of dairy products. The stability and reproducibility of SERS signals mainly depend on the preparation of SERS substrates. This article reviews the preparation methods of SERS substrates in milk testing in recent years, the most study of SERS substrate materials are high-cost precious metal materials, which leads to some limitations in the application of precious metal substrates. Therefore, SERS substrates of new materials are one of the prospects of surface-enhanced Raman spectroscopy research. In addition, the currently reported SERS substrates used in milk detection are only part of the many pollutants in milk, adulterants such as formaldehyde, hydrogen peroxide, dichromic acid and salicylic acid have not been reported.
2021, 42(19): 411-417.
doi: 10.13386/j.issn1002-0306.2020080044
Abstract:
Meat and its products are highly perishable food, and its quality has been the focus of academic attention. Edible film, which is composed of protein, lipid and polysaccharide, can be used as carrier of natural active substance to increase the color, flavor and function of meat products. It can effectively prolong the shelf life of meat products without burdening the environment. Different Meat and meat products need specific packaging conditions, composite bio-based film in the field of meat preservation has broad potential. In this paper, the preparation methods of edible film and its application in meat and meat products at home and abroad are reviewed to provide reference for the application of functional edible film in meat and meat products.
Meat and its products are highly perishable food, and its quality has been the focus of academic attention. Edible film, which is composed of protein, lipid and polysaccharide, can be used as carrier of natural active substance to increase the color, flavor and function of meat products. It can effectively prolong the shelf life of meat products without burdening the environment. Different Meat and meat products need specific packaging conditions, composite bio-based film in the field of meat preservation has broad potential. In this paper, the preparation methods of edible film and its application in meat and meat products at home and abroad are reviewed to provide reference for the application of functional edible film in meat and meat products.
2021, 42(19): 418-428.
doi: 10.13386/j.issn1002-0306.2020080068
Abstract:
Heavy metal ions are highly toxic contaminants in food and environment, which can easily cause foodborne diseases and irreversible damage to human being. There are several limitations in traditional detection methods for heavy metal ions such as time consuming and expensive, so it’s urgent to develop a rapid technology for heavy metal detection in food. Due to their rapid, high sensitivity and specificity, nanomaterial-based electrochemical aptasensors are perspective in real-time detection of heavy metal ions. This paper summarize the characters of metallic nanomaterials (such as gold nanoparticles), metal oxide nanomaterials (such as Fe3O4 nanoparticles), and carbon nanomaterials (such as carbon nanotubes and graphene) and then review the application of electrochemical aptasensors based on nanomaterials in heavy metal detection (mainly lead (II), mercury (II), arsenic (III) and cadmium (II)), in order to provide inspiration for the development of heavy metal detection methods.
Heavy metal ions are highly toxic contaminants in food and environment, which can easily cause foodborne diseases and irreversible damage to human being. There are several limitations in traditional detection methods for heavy metal ions such as time consuming and expensive, so it’s urgent to develop a rapid technology for heavy metal detection in food. Due to their rapid, high sensitivity and specificity, nanomaterial-based electrochemical aptasensors are perspective in real-time detection of heavy metal ions. This paper summarize the characters of metallic nanomaterials (such as gold nanoparticles), metal oxide nanomaterials (such as Fe3O4 nanoparticles), and carbon nanomaterials (such as carbon nanotubes and graphene) and then review the application of electrochemical aptasensors based on nanomaterials in heavy metal detection (mainly lead (II), mercury (II), arsenic (III) and cadmium (II)), in order to provide inspiration for the development of heavy metal detection methods.
2021, 42(19): 429-435.
doi: 10.13386/j.issn1002-0306.2020080312
Abstract:
During the storage of fish, many physical and chemical changes take place, which will cause the quality deterioration of fish. There are many factors that can affect the quality of fish, and endogenous proteases play an important role in quality deterioration. This review focuses on the three endogenous proteases, including matrix metalloproteinases, calpains and cathepsins, which are related to the decline of fish quality during storage. Also the theoretical basis of these three enzymes on fish protein are discussed. The mechanism of quality changes of fish meat induced by endogenous proteases, including flavor, water retention, color and texture, are reviewed in order to clarify the role of endogenous proteases in quality deterioration. Some techniques and methods to inhibit the activity of endogenous proteases in fish meat are reviewed, aiming to provide a reference for the development of quality detection and control technology for fish meat and its products.
During the storage of fish, many physical and chemical changes take place, which will cause the quality deterioration of fish. There are many factors that can affect the quality of fish, and endogenous proteases play an important role in quality deterioration. This review focuses on the three endogenous proteases, including matrix metalloproteinases, calpains and cathepsins, which are related to the decline of fish quality during storage. Also the theoretical basis of these three enzymes on fish protein are discussed. The mechanism of quality changes of fish meat induced by endogenous proteases, including flavor, water retention, color and texture, are reviewed in order to clarify the role of endogenous proteases in quality deterioration. Some techniques and methods to inhibit the activity of endogenous proteases in fish meat are reviewed, aiming to provide a reference for the development of quality detection and control technology for fish meat and its products.
2021, 42(19): 436-442.
doi: 10.13386/j.issn1002-0306.2020090019
Abstract:
Dietary fiber is the "seventh nutrient" of human beings. It has physiological activities such as preventing obesity and regulating intestinal flora. Citrus peel is one of the good sources of dietary fiber, but the current domestic research on citrus peel dietary fiber mainly focuses on the preparation process, and the industrial application of citrus peel dietary fiber in food is still relatively weak. Therefore, the development and utilization of dietary fiber from citrus peel has become a hot research topic. Citrus peel dietary fiber can be used as a dietary supplement in food production because of its excellent physical and chemical properties. Therefore, this article mainly summarizes the types and content of dietary fiber in citrus peel, the nature of dietary fiber, and the application of citrus peel dietary fiber in foods, in order to provide a useful reference for the better development and utilization of dietary fiber in citrus peel.
Dietary fiber is the "seventh nutrient" of human beings. It has physiological activities such as preventing obesity and regulating intestinal flora. Citrus peel is one of the good sources of dietary fiber, but the current domestic research on citrus peel dietary fiber mainly focuses on the preparation process, and the industrial application of citrus peel dietary fiber in food is still relatively weak. Therefore, the development and utilization of dietary fiber from citrus peel has become a hot research topic. Citrus peel dietary fiber can be used as a dietary supplement in food production because of its excellent physical and chemical properties. Therefore, this article mainly summarizes the types and content of dietary fiber in citrus peel, the nature of dietary fiber, and the application of citrus peel dietary fiber in foods, in order to provide a useful reference for the better development and utilization of dietary fiber in citrus peel.
2021, 42(19): 443-450.
doi: 10.13386/j.issn1002-0306.2020090064
Abstract:
Fish oil is rich in n-3 polyunsaturated fatty acids (n-3 PUFA), especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). DHA and EPA can produce eicosanoids with anti-inflammatory properties in the body, such as prostaglandins (PGs), thromboxanes (TX), resolvins (RV), leukotrienes (LTs) and other oxidative derivatives. Moreover, fish oil supplementation can reduce the levels of inflammatory aging related factors (serum IL-6, IL-1, TNF-α and CRP), and has positive preventive effect on inflammatory aging related diseases.In this paper, the icosahedron derivation of DHA and EPA and their relationship with the derivatization of arachidonic acid (AA) are introduced. Meanwhile, based on the relationship between fish oil supplement and inflammatory aging related factors, the effects of dietary fish oil on cardiovascular disease, rheumatoid arthritis, cognitive impairment and type 2 diabetes mellitus in middle-aged and elderly people were summarized. Data have shown that fish oil has a positive clinical effect in reducing inflammatory aging factors, improving dyslipidemia and reducing the symptoms of rheumatoid arthritis.However, there is insufficient evidence of a therapeutic or preventive effect on cognitive impairment and type 2 diabetes.
Fish oil is rich in n-3 polyunsaturated fatty acids (n-3 PUFA), especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). DHA and EPA can produce eicosanoids with anti-inflammatory properties in the body, such as prostaglandins (PGs), thromboxanes (TX), resolvins (RV), leukotrienes (LTs) and other oxidative derivatives. Moreover, fish oil supplementation can reduce the levels of inflammatory aging related factors (serum IL-6, IL-1, TNF-α and CRP), and has positive preventive effect on inflammatory aging related diseases.In this paper, the icosahedron derivation of DHA and EPA and their relationship with the derivatization of arachidonic acid (AA) are introduced. Meanwhile, based on the relationship between fish oil supplement and inflammatory aging related factors, the effects of dietary fish oil on cardiovascular disease, rheumatoid arthritis, cognitive impairment and type 2 diabetes mellitus in middle-aged and elderly people were summarized. Data have shown that fish oil has a positive clinical effect in reducing inflammatory aging factors, improving dyslipidemia and reducing the symptoms of rheumatoid arthritis.However, there is insufficient evidence of a therapeutic or preventive effect on cognitive impairment and type 2 diabetes.
2021, 42(19): 451-458.
doi: 10.13386/j.issn1002-0306.2020100217
Abstract:
Protease is the most widely used industrial enzyme preparation, and its sales volume accounts for 60% of the total amount of enzyme preparations in the world. More than two-thirds of industrial protease is produced by microbial fermentation. In this paper, the industrial production strains of microbial protease, the selection of high-yield strains, enzymatic properties, separation and purification methods and application in food industry are summarized, in order to better understand microbial protease. It lays a foundation for further research and exploration of microbial protease and industrial production of protease.
Protease is the most widely used industrial enzyme preparation, and its sales volume accounts for 60% of the total amount of enzyme preparations in the world. More than two-thirds of industrial protease is produced by microbial fermentation. In this paper, the industrial production strains of microbial protease, the selection of high-yield strains, enzymatic properties, separation and purification methods and application in food industry are summarized, in order to better understand microbial protease. It lays a foundation for further research and exploration of microbial protease and industrial production of protease.
More+
Submission Guidelines
Download Center
