不同Ca^2+浓度下猪肉肌球蛋白的热聚集体机制研究  

Effects of Different Ca^2+ Concentrations on Heat-induced Aggregation of Pork Myosin

作　　者：潘腾 陈星 沈清武 张炎 罗洁 PAN Teng;CHEN Xing;SHEN Qingwu;ZHANG Yan;LUO Jie(Newhope Liuhe Co.,Ltd.,Beijing 100102,China;Key Laboratory of Feed and Livestock and Poultry Products Quality&Safety Control,Ministry of Agriculture and Rural Affairs,Beijing 100102,China;College of Food Science and Technology,Hunan Agricultural University,Changsha 410128,China;College of Food Science and Nutritional Engineering,China Agricultural University,Beijing 100083,China)

机构地区：[1]新希望六和股份有限公司,北京100102 [2]农业农村部饲料及畜禽产品质量安全控制重点实验室,北京100102 [3]湖南农业大学食品科学技术学院,长沙410128 [4]中国农业大学食品科学与营养工程学院,北京100083

出　　处：《农业机械学报》2020年第9期329-336,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金青年科学基金项目(31801572);国家重点研发计划项目(2018YFD0401205);现代农业产业技术体系北京市生猪产业创新团队项目(BAIC02-2019)。

摘　　要：为探究不同Ca^2+浓度下肌球蛋白的热聚集行为,以猪背最长肌为原料,提取其肌球蛋白,加入不同浓度的氯化钙(0.01、0.02、0.03、0.04、0.05、0.075、0.1 mol/L),通过热变性动力学分析,研究加热过程中聚集体形态结构的变化和凝胶特性,探究猪肉肌球蛋白热聚集形成机制。结果表明,氯化钙浓度由0.01 mol/L升至0.1 mol/L,蛋白变性温度由40.2、52.4℃降至36.5、50.8℃,显著(p<0.05)降低了肌球蛋白的热稳定性;随着温度的升高、氯化钙浓度的增加,肌球蛋白浊度、粒度、变性率逐步增大;显著(p<0.05)提高了肌球蛋白初始状态的Ca^2+ATP酶活性,降低了肌球蛋白互相结合形成聚集体的温度;电镜观察发现,Ca^2+浓度越高,聚集速率越快,0.1 mol/L处理下,蛋白聚集体体积显著增大,形成无序聚集体;80℃、0.1 mol/L处理组凝胶强度显著(p<0.05)高于其他处理组,氯化钙浓度由0.01 mol/L升高至0.1 mol/L,凝胶强度由4.58 N升至5.28 N。因此,随着温度升高、氯化钙浓度增加,易形成猪肉肌球蛋白聚集体,且凝胶强度增加。In order to investigate the thermal aggregation behavior of myosin at different Ca^2+concentrations,the myosin was extracted from longissimus dorsi muscle of pigs.By adding different concentrations of calcium chloride(0.01 mol/L,0.02 mol/L,0.03 mol/L,0.04 mol/L,0.05 mol/L,0.075 mol/L and 0.1 mol/L),the changes of morphology and structure of aggregates during the heating process and gel properties were studied by means of thermal denaturation kinetics,differential fluorescence scanning instrument and negative staining transmission electron microscope.The aim was to elucidate the mechanism of myosin thermal aggregation in pork.The results showed that the concentration of Ca^2+was increased from 0.01 mol/L to 0.1 mol/L,the denaturation temperature of protein was decreased from 40.2℃and 52.4℃to 36.5℃and 50.8℃,the thermal stability of myosin was decreased significantly(p<0.05);with the increase of temperature and calcium chloride concentration,the turbidity,particle size and denaturation rate of myosin were increased gradually;the activity of Ca^2+ATPase was increased significantly(p<0.05)at the initial state of myosin,and the temperature of myosin binding to form aggregates was decreased.Electron microscope observation showed that the higher the concentration of Ca^2+was,the faster the aggregation rate was.Under the concentration of 0.1 mol/L CaCl2,the volume of protein aggregates was increased significantly to form disordered aggregates.The concentration of Ca^2+was increased from 0.01 mol/L to 0.1 mol/L,and the gel strength was increased from 4.58 N to 5.28 N.Gel strength of 80℃and 0.1 mol/L calcium chloride treatment group was significantly(p<0.05)higher than other treatment groups.Therefore,with the increase of temperature and calcium chloride concentration,pork myosin aggregates were easy to form and the gel strength was increased.

关 键 词：猪肉肌球蛋白 氯化钙浓度 聚集机制 

分 类 号：TS251.5[轻工技术与工程—农产品加工及贮藏工程]