Gelling Properties of Actomyosin from Pre- and Post-Spawning Hake (Merluccius hubbsi)

ABSTRACT The biochemical properties and the characteristics of heat‐induced gelation of natural actomyosin (NAM) from pre‐ and post‐spawning hake were studied. Mg2+ ATPase activity, reduced viscosity and myosin/actin mole ratio of NAM from post‐spawning fish were higher than those of pre‐spawning ones. Gelation of both actomyosin at 10 mg mL−1 of protein concentration was optimal at 60°C and pH 6.0. The highest rigidity was reached at 0.40M and 0.44M KCl with NAM from pre and post‐spawning hake, respectively. Irrespective of heating temperature, ionic strength conditions and at pH range 5.5–7.5, rigidity of post‐spawning hake NAM gels was higher than those of pre‐spawning fish. Scanning electron micrographs of pre‐ and post‐spawning hake NAM showed “actin‐type” and “myosin‐type” ultrastructures, respectively.