Influence of gender and spawning on thermal stability and proteolytic degradation of proteins in Australian red claw crayfish (Cherax quadricarinatus) muscle stored at 2 °C

Thermal stability and proteolytic degradation of male (M), nonspawning female (F) and spawning female (SF) red claw crayfish (Cherax quadricarinatus) muscle proteins during refrigerated storage (2 °C) were investigated. The thermal transition temperatures (T_max) of myosin and actin remained relatively constant during storage, but their enthalpies of denaturation (ΔH) increased, especially in SF samples. SF muscle proteins were more heat‐stable (greater T_max and ΔH values, P < 0.05) than M and F muscle proteins. Protein degradation occurred in all muscle groups, more rapidly in M and F muscles than in SF muscle. The diminishments of a 69‐kDa component and troponin‐I and the appearance of a 55‐kDa polypeptide represented the most salient proteolytic changes. The results suggested that the spawning status was a more significant factor than gender in affecting the quality of red claw muscle proteins and their changes during refrigerated storage.