Abstract
Fish protein hydrolysate (FPH) was prepared from the underutilized residues of 3-marine fish species disposed of by-products processing by protease treatment. The major component of the FPH was hydrolyzed protein (82-86%). The concentration dependent protective effect of FPH (2.5-10.0%, dry weight/wet weight) on the wanieso lizardfish (Saurida wnieso) frozen surimi at -25°C was evaluated by determining gel-forming ability, unfrozen water, and myofibrillar Ca-ATPase activity. The gel-forming ability and total myofibrillar Ca-ATPase activity of the surimi with FPH showed significantly higher values than those of without FPH (control) during frozen storage. The amount of unfrozen water in the frozen surimi with FPH was significantly increased compared to that in the control. The results indicate that FPH stabilized the hydrated water surrounding myofibrils. These findings suggest that the FPH prevent the freeze-induced denaturation of the surimi during frozen storage.