鳙鱼宰后pH值和僵直指数的变化及其对盐溶蛋白凝胶特性的影响

Changes in Muscle pH and Rigor Index of Big Head Carp during Ice Storage and Their Effects on Gel Properties of Salt-Soluble Proteins from Big Head Carp

以鳙鱼为材料,研究宰后冰藏期间pH值和僵直指数的变化及其对鳙鱼盐溶蛋白热诱导凝胶特性的影响。结果表明:宰后鳙鱼pH值迅速降低,宰后冰藏10h时pH值由7.26降至6.51,冰藏48h后pH值开始上升。僵直指数从宰后冰藏19h开始增加,48h达到最大,最大僵直指数为72.1%。宰后冰藏1h的鳙鱼盐溶蛋白凝胶强度最低,随着僵直指数的增加,凝胶强度不断增大,僵直指数最大时,凝胶强度最大。当僵直指数开始下降,凝胶强度缓慢降低。

The changes in muscle pH and rigor index during ice storage of big head carp and their effects on heat-induced gel properties of salt-soluble proteins from big head carp were determined.The experimental results indicated that the muscle pH of the fish obviously decreased from 7.26 to 6.51 after 10 h of post-mortem ice storage and then began to increase after 48 h.The rigor index began to increase after 19 h of post-mortem ice storage,and reached its maximum value after 48 h,72.1%.The lowest gel strength was observed for heat-induced gels from salt-soluble proteins extracted from big head carp muscle ice-stored for 1h.The gel strength was found to increase with increasing rigor index and they reached their maximum levels at the same time.The gel strength slowly decreased as the rigor index began to decrease.