On heat coagulation of water soluble proteins from deep sea fishes

The heat coagulation of water soluble proteins from walleye pollack, rat-tail, morid fish, eel-pout, halibut, and mackerel was examined to compare the difference in thermostabillty among fish species. From the thermodynamic parameters accompanying the heat coagulation process, it was shown that van't Hoff plots gave two lines with different slope in the temperature range of between 50° to 60°C. The ΔG° of walleye pollack, rat-tail, and morid fish showed the negative values at both 50° and 80°C. The results suggested that the thermostability of these fish proteins was lower, compared to that of the other fishes examined. The thermal reaction at 50°C resulted in a large value of the ΔS°.