不同待宰季节对驴肉宰后成熟中Hsp70表达量及肌肉组织结构的影响

Influence of slaughter in different seasons on the expression of Hsp70 and muscle tissue structure during the postmortem aging of donkey meat

为研究不同待宰季节对驴肉成熟中热休克蛋白70表达量(Heat shock protein 70,Hsp70)及肌肉组织结构的影响,本文以3岁龄‘三粉母驴’为研究对象,分别在冬、春、夏3季进行屠宰,测定驴肉在成熟过程中挥发性盐基氮(Total volatile basic nitrogen,TVB-N)、肌原纤维小片化指数(Myofibril fragmentation index,MFI)、Hsp70表达量、肌肉组织结构等指标的差异。结果表明:夏季组pH值1~3 d显著低于冬、春两季(P<0.05),4~7 d显著高于春季组(P<0.05);夏季组滴水损失显著高于春、冬两季(P<0.05),MFI值、TVB-N值、肌原纤维蛋白溶出量、糖原含量显著高于冬季组(P<0.05);冬季组pH值高于春季组,1~3 d显著高于夏季组(P<0.05);冬季组滴水损失、TVB-N值、MFI值、肌原纤维蛋白溶出量、糖原含量显著低于夏季组(P<0.05)。冬、夏两季Hsp70含量显著高于春季组(P<0.05)。夏季组肌纤维间隙大于春冬两季,形状更不规则。研究认为,夏季、冬季屠宰会增加驴肉中Hsp70表达量,对驴肉品质产生负面影响。

In order to study the effect of different slaughter seasons on the expression of heat shock protein 70(Hsp70)and muscle tissue structure of the donkey meat during the postmortem aging,the three-years-old‘Sanfen’female donkey was taken as the research object,and was slaughtered in winter,spring and summer.The difference among indices such as Hsp70,total volatile basic nitrogen(TVB-N),glycogen content,myofibril fragmentation index(MFI),and muscle tissue structure,were investigated.The results showed that the pH value of the summer group was significantly lower than that of spring and winter groups duriry the 1-3 d(P<0.05),and was significantly higher than that of spring group during the 4-7 d(P<0.05).The drip loss in summer group was significantly higher than that of spring and winter groups(P<0.05).The MFI value,TVB-N value,myofibrilar protein solubility,glycogen content in summer group were significantly higher than those in winter group(P<0.05);The pH value of the winter group was significantly higher than that of the spring group,and was higher than summer group on 1st^3rd.The drip loss,MFI value,TVB-N value and myofibrillar protein dissolution in winter group were significantly lower than summer group(P<0.05).The Hsp70 content of summer and winter groups were significantly higher than that of the spring group(P<0.05).The muscle fiber gap of summer group was significantly higher than that of the spring and winter groups,with the shape was more irregular.The results indicated that slaughter in summer and winter will increase the expression of Hsp70 in the donkey meat and have a negative impact on the quality of donkey meat.