Effects of Ultrasound and TGase on Physicochemical Properties of Grass Carp Meat during Restructuring

In this study,four treatment methods including control group(only adding NaCl),experimental group 1(adding NaCl and TGase),experimental group 2(adding NaCl then ultrasound),and experimental group 3(adding NaCl and TGase then ultrasound)were used to restructure the grass carp meat respectively. The effects of ultrasound and TGase on the physicochemical properties of grass carp meat during restructuring were analyzed based on the measurement of the intermolecular force,sulfhydryl content,turbidity,dissolution rate,etc. The results showed that ultrasound and TGase had different effects on ionic bonds,hydrogen bonds,hydrophobic interactions,disulfide bonds,and non-disulfide bonds,and promoted the formation of recombinant grass carp meat. In addition,it was found that ultrasound and TGase could accelerate the oxidation of sulfhydryl groups of myofibrillar protein to disulfide bonds,enhance surface hydrophobicity and turbidity of myofibrillar protein,and reduce the protein solubility of recombinant grass carp meat. According to the results of SDS-PAGE electrophoresis,the bands around 200 kDa in the three experimental groups faded gradually or even disappeared during restructuring. It could be seen that ultrasound and TGase mainly acted on myofibrillar protein heavy chain during the reorganization. The results demonstrated that both ultrasound and TGase could promote the cross-linking of grass carp protein,and the degree of cross-linking was the highest during interaction,which had certain reference value for guiding the production of grass carp meat industry.