New insights into the cross-linking between myosin and alkali-treated pea protein by transglutaminase under low ionic conditions: Contribution of legumin and vicilin fractions

This study investigated the cross-linking of myosin with pH(12)-shifted legumin (11S(pH)) or vicilin (7S(pH)), and the gel properties of composite gels, with or without transglutaminase, in 0.3 M NaCl. The free sulfhydryl content of 7S(pH)/11S(pH) increased significantly (P < 0.05). The covalent cross-linking degree between 7S(pH)/11S(pH) and myosin was enhanced, with the vicilin of approximately 45 kDa showing more pronounced cross-linking. SDS-PAGE analysis of myosin subfragments revealed that S1 and light meromyosin were the primary cross-linking regions for 11S(pH), reducing the Ca2+-ATPase activity of the myosin head, while S2 was an alternative cross-linking region for 7S(pH). The cross-linking of 7S(pH)/11S(pH) enhanced the thermal aggregation of S1. The cross-linking degree of tails followed this order: myosin > myosin+7S(pH) > myosin+11S(pH). Thus, the use of 7S(pH)/11S(pH) and transglutaminase offers a new approach to improving texture in low-salt meat products.