Effects of natural trypsin inhibitor from soybean on texture deterioration of the bay scallop ( Argopecten irradians ) during cold storage and its mechanism

Summary In this study, the inhibitory effects of natural trypsin inhibitor from soybean (SBTI) on texture deterioration of adductor muscle of scallop (AMS) during cold storage and its mechanism were revealed by determining the changes of structural proteins of AMS in situ and in vitro , respectively. Results indicated that the endogenous proteolysis resulted in the disintegration of connective tissue proteins, the degradation of myosin and actin, as well as the reduction of α‐helix, the increase of β‐sheet and amino acid side chains, and the exposure of tryptophan residues of isolated myofibrillar proteins (MPs). These changes in structural proteins contribute to the texture deterioration of AMS as reflected in a significant decrease in hardness, chewiness, adhesiveness and springiness, but a significant increase in cohesiveness. SBTI significantly inhibited the conformational changes of structural proteins caused by endogenous proteolysis, improved the MP gel‐forming ability and consequently retarded the texture deterioration of AMS.