Effect of Enzymatic Fish Protein Hydrolysate from Fish Scrap on the State of Water and Denaturation of Lizard Fish (Saurida wanieso) Myofibrils during Dehydration

Abstract

Fish protein hydrolysate (FPH) was prepared from scraps of 5 marine species, in order to utilize by-products effectively by protease treatment. Protein was the major component of the FPH ranging 82–86%. The effects of 5% FPH (dried weight/wet weight) on the state of water and the denaturation of lizard fish Saurida wanieso myofibrils were evaluated by desorption isotherm curves, Ca-ATPase activity, and differential scanning calorimetry (DSC) during dehydration. The myofibrils with FPH showed a decreased water activity (Aw), while they exhibited significantly higher Ca-ATPase activity compared to myofibrils without FPH (control). The myofibrils with FPH had higher amount of unfrozen water than the control. These results suggest that the FPH suppressed dehydration-induced denaturation, which seems to be attributable to the stabilization of the hydrated water surrounding the myofibrils.