低压电刺激对不同部位宰后牦牛肉肌原纤维蛋白水解的影响  

Effect of low voltage electrical stimulation on myofibrillar proteolysis of different parts of yak meat

作　　者：贾青[1] 余群力[1] 田园[1] 孙志昶[1] 李洪波 

机构地区：[1]甘肃农业大学食品科学与工程学院,甘肃兰州730070 [2]甘肃陇原中天生物工程股份有限公司,甘肃陇西748100

出　　处：《食品工业科技》2015年第5期53-57,共5页Science and Technology of Food Industry

基　　金：国家现代农业(肉牛牦牛)产业技术体系资助项目(CARS-38);国家科技支撑计划(2012BAD28B01)

摘　　要：研究电刺激对不同部位牦牛肉宰后成熟过程中微观结构及肌原纤维蛋白水解的影响。将牦牛宰后5min内进行低压电刺激（21V,50Hz,90s）并冷却排酸,于宰后0、1、3、5d取前部肱三头肌（TB）中部背最长肌（ML）和后部半膜肌（SM）,分析其肌节长度、肌纤维直径、MFI指数、肌原纤维超微结构和全肌肉蛋白电泳图谱。结果表明：电刺激使不同部位牦牛肉肌节长度显著变化（p〈0.05）,肌纤维直径平均缩小6%、5%和9%;TB、ML和SM宰后0-5d MFI值分别上升54%、55%和92%,SM嫩度显著增大（p〈0.01）;不同部位牦牛肉肌原纤维超微结构中挛缩带占有率分别为23.9%、26.3%和31.2%,肌原纤维结构形变溶解;SDS-PAGE电泳图谱显示,TB、ML和SM部肌原纤维蛋白均在48-75ku之间降解彻底。本研究证实了电刺激缩短牦牛肉宰后成熟时间,对不同部位牦牛肉嫩度改善,特别是对肉质较差的SM效果显著。After being treated by electrical stimulation in yak meat, changes in microstructure and myofibrillar proteolysis were studied.The raw materials were yaks slaughtered with electrical stimulation within 5min （21V,50Hz, 90s）, and then chilled （0-4℃, wind speed 0.5 m/s） .Taking front triceps （ TB）, central Iongissimus muscle （ML） and posterior semimembranosus （SM）as material, respectively, then determined sarcomere length, muscle fiber diameter, MFI value, muscle fiber microstructures and SDS-PAGE electrophoresis after postmortem 0, 1,3 and 5d. The results indicated that after electrical stimulation, sarcomere length of different parts of yak meat changed significantly（ p 〈 0.05）;the average diameter of the muscle fibers shortened 6% ,5% and 9% repectively, MFI values increased by 54% ,55% and 92% significantly,tenderness of SM increased significantly（p 〈0.05）.Share of different parts of yak meat myofibrillar ultrastructure contracture were 23.9%, 26.3% and 31.2%. Myofibrillar ultrastructural changed significantly.The view of the SDS-PAGEphotograph, TB, ML and SM Myofibrillar protein degradated completely between 48-75ku.In a conclusion, electrical stimulation could shorten the aging time, and improve tenderness of yak meat,especially, make a significant difference to poorer SM part（p 〈0.05）.

关 键 词：牦牛 电刺激 宰后成熟 肌原纤维蛋白 

分 类 号：TS251.1[轻工技术与工程—农产品加工及贮藏工程]