Effect of high pressure on gelation of meat paste and inactivation of actomyosin Ca-ATPase prepared from milkfish

Milkfish was used as a raw material to establish and obtain fundamental data about the gelation of meat paste and inactivation of actomyosin Ca-ATPase by means of high pressure-treatment. Suwari, a setting phenomenon at low temperature, occurred at 50 degrees C, while modori, a disintegrating phenomenon at high temperature, occurred at 60-70 degrees C. The suwari temperature of meat paste treated at 3,000 atm for 1 h decreased from 50 to 30 degrees C. Excellent gel was obtained after pressurizing at 1,000, 3,000, and 5,000 atm for 1 h and subsequently heating at 90 degrees C for 10 min. Heat-induced suwari was improved and modori was inhibited after pressuring at 3,000 atm for 1 h. The activity of Ca-ATPase was almost lost by treating at 3,000 atm for 5 min. Different patterns in Ca-ATPase inactivation were observed when actomyosin was treated by pressurizing, heating after pressurizing, or pressurizing combined heating. Liability to denaturation of the protein indicated that pressure treatment was applicable to milkfish processing.