Myosin denaturation and cross-linking in Alaska pollack salted surimi during its preheating process as affected by temperature

Abstract

Myosin denaturation and cross-linking during the preheating process of Alaska pollack salted surimi at various preheating temperatures were studied. Thermal gel properties of preheated-gel and those after heating at 90°C were measured. At 15°C and 25°C, loss of salt-and urea-solubility of myosin preceded ATPase inactivation and cross-linking. At 35°C, a very quick ATPase inactivation and loss of salt-solubility was followed by a loss of urea-solubility of myosin. Myosin cross-linking reaction followed these changes. Preheating at these temperatures increased the breaking force of the two-step heated gel. At 45°C, despite a quick loss of ATPase and salt-solubility, urea-solubility remained high and no cross-linking was observed. Furthermore, there was no increment in breaking force upon preheating at this temperature. Thus, myosin aggregates, as revealed by the loss of urea-solubility as well as the cross-linking reaction, were important in improving thermal gel properties.