Inhibiting effect of polymerization and degradation of myosin heavy chain during preheating at 30oC and 50oC on the gel-forming ability of walleye pollack surimi

Abstract

To confirm the contribution of polymerization and degradation of myosin heavy chain (MHC) during preheating to the gel-forming ability of fish meat paste, walleye pollack surimi paste was preheated at 30∞C and 50∞C prior to heating at 80∞C in the presence of various inhibitors. At 30∞C, ethyleneglycol bis(2-aminoethyl ether)-N,N,N¢,N¢-tetraacetic acid (EGTA) and ethylenedi- aminetetraacitic acid (EDTA) inhibited gel formation as well as the polymerization of MHC, whereas dithiothreitol (DTT) and leupeptin promoted gel formation, which was accompanied by the enhance- ment of MHC polymerization and decreased MHC degradation, respectively. At 50∞C, leupeptin inhib- ited MHC degradation and improved gel strength, whereas EGTA, EDTA and DTT had no effect on MHC polymerization and degradation and did not affect gel formation. The results demonstrate that the gel strength of cooked gel (80∞C) is not affected by preheating at 30∞C and 50∞C and does not inhibit polymerization and degradation. Results suggest that the gel strength of cooked gel is depen- dent on the polymerization and degradation of MHC during preheating.