梅山猪与三元杂交猪肌内脂肪含量、μ-钙蛋白酶和蛋白降解对嫩度的影响  

Effect of Intramuscular Fat Content,μ-Calpain and Protein Degradation on Pork Tenderness:a Comparative Study between Meishan and Three-Crossbred Pigs

作　　者：王娟[1] 闫祥林[1] 周光宏[1] 徐幸莲[1] 张万刚[1] 

机构地区：[1]南京农业大学食品科技学院,肉品加工与质量控制教育部重点实验室,食品安全与营养协同创新中心,江苏南京210095

出　　处：《食品科学》2015年第13期52-56,共5页Food Science

基　　金：“十二五”国家科技支撑计划项目(2012BAD28B03)

摘　　要：目的:比较梅山猪与三元杂交猪(杜洛克猪×长白猪×大白猪)的剪切力、肌内脂肪含量、μ-钙蛋白酶及蛋白降解的差异,分析影响梅山猪肉嫩度的因素。方法:选取6头纯种梅山猪和6头三元杂交猪,取背最长肌为实验材料,采用变性聚丙烯酰胺凝胶电泳和蛋白免疫印迹技术测定μ-钙蛋白酶在宰后45 min的降解和整联蛋白、伴肌动蛋白在宰后成熟1、3、7 d的降解情况。结果:梅山猪肉在宰后成熟1、3、7 d的剪切力值均显著低于三元杂交猪(P<0.05),在宰后成熟1 d的肌内脂肪含量显著高于三元杂交猪(P<0.05)。在宰后45 min,梅山猪的μ-钙蛋白酶的80 kD百分含量显著高于三元杂交猪,78 k D和76 kD百分含量显著低于三元杂交猪(P<0.05),梅山猪的μ-钙蛋白酶的自我降解程度较低,这与梅山猪的蛋白降解情况相一致。梅山猪的整联蛋白在成熟3d的相对光密度值显著高于三元杂交猪(P<0.05),宰后成熟3 d和7 d的降解率显著低于三元杂交猪(P<0.05),伴肌动蛋白在成熟1 d和3 d的相对光密度值显著高于三元杂交猪(P<0.05)。结论:梅山猪的整联蛋白和伴肌动蛋白降解较少,这与μ-钙蛋白酶的降解有关,而μ-钙蛋白酶和蛋白降解对梅山猪肉的嫩度影响不大,梅山猪肉相对较高的肌内脂肪含量解释了其较高的嫩度。Objective：To compare the difference in shear force,intramuscular fat content,μ-calpain and protein degradation between Meishan and crossbred pigs in order to explore the factors contributing to the tenderness of Meishan pork.Methods：Six purebred Meishan pigs and six crossbred pigs（Duroc × Landrace × Yorkshire） were slaughtered.μ-Calpain at 45 min postmortem,integrin and nebulin degradation at 1,3 and 7 d of postmortem aging were determined by polyacrylamide gel electrophoresis（PAGE） and western blotting.Results：Meishan pork presented lower shear force and higher intramuscular fat content compared to crossbred pork（P 0.05）.At 45 min postmortem,crossbred pork presented enhanced degradation of μ-calpain,as evidenced by significantly lower proportions of 80 k D fragments and significantly higher proportions of 78 k D and 76 k D fragments percentage compared to Meishan pork（P 0.05）.Lessened degradation of μ-calpain in Meishan pork at 45 min postmortem potentially forecasted that Meishan pork could have lower protein degradation during the subsequent aging time.The degree of integrin degradation was lower in Meishan pork compared to crossbred pork at 3 and 7 d of postmortem aging.Additionally,the relative optical density of nebulin was lower in Meishan pork compared to crossbred pork at 1 and 3 d of postmortem aging,which represents lower degradation of nebulin.Conclusion：μ-calpain and protein degradation may not be key factors contributing to the higher tenderness of Meishan pork,while the higher intramuscular fat content may help explain the lower shear force in Meishan pork.

关 键 词：梅山猪 μ-钙蛋白酶 整联蛋白 伴肌动蛋白 

分 类 号：TS251.1[轻工技术与工程—农产品加工及贮藏工程]