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

To confirm the contribution of polymerization and degradation of myosin hea vy chain (MHC) during preheating to the gel-forming ability of fish meat pa ste, walleye pollack surimi paste was preheated at 30 degreesC and 50 degre esC prior to heating at 80 degreesC in the presence of various inhibitors. At 30 degreesC, ethyleneglycol bis(2-aminoethyl ether) -N,N,N'N'-tetraaceti c acid (EGTA) and ethylenediaminetetraacitic acid (EDTA) inhibited gel form ation as well as the polymerization of MHC, whereas dithiothreitol (DTT) an d leupeptin promoted gel formation, which was accompanied by the enhancemen t of MHC polymerization and decreased MHC degradation, respectively. At 50 degreesC, leupeptin inhibited MHC degradation and improved gel strength, wh ereas EGTA, EDTA and DTT had no effect on MHC polymerization and degradatio n and did not affect gel formation. The results demonstrate that the gel st rength of cooked gel (80 degreesC) is not affected by preheating at 30 degr eesC and 50 degreesC and does not inhibit polymerization and degradation. R esults suggest that the gel strength of cooked gel is dependent on the poly merization and degradation of MHC during preheating.