Hydrogen and other polar bondings in fish flesh gel and setting gel.

Abstract

Hydrogen and other polar bondings are known to become stronger at lower temperature. Here the physical properties of muscle protins were determined during heating at 80°C for 20min (fish flesh gel) and at 40°C for 60min (setting gel). On heating the actomyosin sols at 40°C and 80°C, their electrostatic capacities, determined with an AC bridge (1K Hz), increased. This increase was larger at 80°C than at 40°C. The electrostatic capacities decreased on cooling and increased again on reheating. The capacities deccreased on the addition of wheat starch (5% of the sol). The shear modulus of the resulting gels increased on cooling. On heating the actomyosin solution at 40°C, its viscosity increased after an initial rapid decrease. On cooling the solution in the course of heating, its viscosity increased further, this increment was cancelled on reheating. Based on the above results, the relationship between hydrophobic amino acid residues and the hydrophilic ones during the formation of the fish flesh gel and the setting was discussed.