Effect of Heat Treatment on the Emulsifying Properties of Carp Myosin

Abstract

Myosin solutions were prepared and heated at 20°, 40°, 60°, 80°, and 100°C for 15min atneutral pH, and the emulsifying properties of the heat-treated myosins were investigated.
Emulsification of myosin and triolein was carried out by sonification at 60W for 1min. Aninverse relation was observed between the emulsifying properties and heating temperature of myosin solutions.
Vector analysis showed that the emulsions were dcmulsified in the direction ofocculation and coalescence when the heating temperature of myosin was 40°C or below and that of separation (i.e. creaming) and coalescence when the heating temperature was 60°C or above.
As for the interaction between protein and lipids, adsorption of myosin to triolein globules by the emulsification process showed the Low affinity type. The higher the heating temperature and the greater the amount of myosin adsorbed, the greater the concentration of myosin in theadsorbing membrane.
It was concluded that the interfacial phenomena of myosin were affected by the heat denatura-tion of myosin. In addition, the interfacial phenomena suggest a remarkable change near 45°C (transition temperature). The transition temperature for the heat denaturation was calculated from the change in the hydrophobicity.