Abstract:
To promote the usage of oil palm in food industry,the nutrition value and functional properties of glutelin-2 were studied in this paper. The glutelin-2 was extracted from defatted oil palm with stepwise extraction method,and its amino acid composition,
in vitro digestibility and biological value,emulsifying property and viscosity were studied. Results showed that the contents of total essential amino acid(48.65 g/100 g)of defatted oil palm glutelin-2(DOPG-2)was much higher than the standard recommend by FAO/WHO(12.7 g/100 g,
P<0.05),and the contents of sulphur-containing amino acid,branched amino acids and asparagines were all high. Moreover,the biological value and
in vitro digestibility of DOPG-2 were 63.03 and 70.02 g/100 g,respectively. It meant that the nutritional value of DOPG-2 was high. Result of Bigelow parameters analysis demonstrated that the ratio of polar side chains to nonpolar side chains of DOPG-2 was 2.18,and its surface hydrophobicity was 37.29. SDS-PAGE analysis showed that there were 5 subunits with mlecular weight of 22.1~133.5 kDa,and some disulfide bonds in DOPG-2. Furthermore,DOPG-2 exhibit significant higher emulsifier capacity(251.58±5.28)m
2/g and emulsion stability(84.40%)than that of soy protein isolate(32.57 m
2/g). And its foam stability(17.61%)and viscosity(21.33 cp)were similar with that of soy protein isolate. These results indicated that DOPG-2 had relatively high nutritional value and functional properties,could be used as a nutrient enhancer,emulsifier,thickener and other products.