饥饿胁迫对南美白对虾冷藏保鲜效果的影响与酶学机制研究

Preservation effect and enzymatic mechanism of starvation stress for Penaeus vannamei during chilled storage

为评价饥饿胁迫对南美白对虾保鲜效果及其内源性酶活力的影响,本实验对南美白对虾进行饥饿胁迫后4℃冷藏,以感官、生化和细菌总数为指标评价其保鲜效果,并检测饥饿胁迫下对虾内源性蛋白酶和酚氧化酶的变化。结果表明：饥饿胁迫处理4d可较好控制对虾因腐败引起的p H与TVB-N值的升高,微生物的生长受到明显抑制,较好地保持了对虾的感官品质。与对照组相比,饥饿胁迫4d可使内源性蛋白酶活力降低41.2%,但对酚氧化酶活力影响无显著性差异（p〉0.05）。综合分析,饥饿胁迫处理4d保鲜效果最佳,与对照相比可延长货架期1~2d,其作用机理之一是通过抑制内源性蛋白酶活力来延缓对虾品质下降。

The study was conducted to investigate the preservation effect and enzymatic mechanism of starvation stresses in Penaeus vannamei.Shrimps were exposed to starvation stresses and then preserved at 4℃.In order to evaluate the effect of starvation stresses on quality changes of shrimps, sensory evaluation, biochemical indicator and total bacteria count were determined,and the influences of starvation on the activities of polyphenol oxidase and protease were studied.The results showed that the group with starvation treatment for 4d could restrain the increase of pH and TVB- N value, reduce the change of total bacteria counts and keep the sensory quality of shrimp significantly.Compared with control group,the endogenous protease activity of the group with starvation stress for 4d were reduced by 41.2%, but there were no significant differences（ p 〉 0.05）in the impact on phenol oxidase activities.The group with starvation stress for 4d had good preservation effect and could prolong the shelf -life for 1-2d,the mechanism was to inhibit the activity of endogenous protease and delay the quality decline in shrimp.