加热温度对混合肉肌原纤维蛋白质结构的影响  

Effects of temperature on the structure of myofibrillar protein in blended meat

作　　者：桂萍 罗永康[1] 冯力更[1] GUI Ping;LUO Yongkang;FENG Ligeng(College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China)

机构地区：[1]中国农业大学食品科学与营养工程学院,北京100083

出　　处：《中国农业大学学报》2018年第5期93-101,共9页Journal of China Agricultural University

基　　金："十二五"国家科技支撑计划项目(2015BAD28B00);国家现代农业产业技术体系建设专项(CARS-46)

摘　　要：为更好地了解鲢鱼(Hypophthalmichthys molitrix)肉、鸡胸肉和混合肉(鲢鱼肉与鸡肉质量比1∶1)中肌原纤维蛋白质在加热过程中理化特性的变化,对不同温度条件下盐溶性蛋白质质量浓度、巯基质量摩尔浓度以及蛋白质构象变化和分子量分布(SDS-PAGE)进行研究。结果表明:随温度升高,3种肉蛋白质质量浓度均下降至1.00mg/mL以下,巯基质量摩尔浓度均下降60%以上,色氨酸荧光强度与α螺旋含量均降低至某一水平后基本保持不变。混合肉肌原纤维蛋白质与鸡胸肉盐溶性蛋白质质量浓度、巯基质量摩尔浓度,以及色氨酸荧光强度与α螺旋含量的下降趋势类似,0~40℃基本保持不变,而后剧烈下降,50℃时下降到最低;鲢鱼肌原纤维蛋白质则在0~30℃变化缓慢,之后迅速下降,40℃时下降到最低。变性温度和SDS-PAGE结果显示:鲢鱼肉、混合肉和鸡胸肉肌球蛋白质重链分别在40、50和50℃时减少,这表明在加热过程中,3种肉蛋白质在变性温度附近,肌球蛋白质重链聚集、蛋白质分子构象发生变化;另外,混合肉肌原纤维蛋白质的热变性规律与单一蛋白质略有差异,能够结合单一蛋白质的优点,改善温度对蛋白质结构的影响。The physiochemical changes of myofibrillar protein from silver carp,chicken breast and their mixture（m（silver carp）∶ m（chicken）=1∶1）were investigated by measuring the content of salt-soluble protein and sulfhydryl group,and the changes of protein conformation and SDS-PAGE during heating also analyzed.The results showed that：The content of salt-soluble protein decreased to 1.00 mg/mL,and the total content of sulfhydryls decreased over 60%,and the fluorescence intensity of the tryptophan and the content of theα-helix decreased to a stable level with temperature for three proteins.The changes of the blended myofibrillar protein were similar to chicken breast myofibrilIar,which was previously expected to be constant from 0 to 40 ℃,then dropped dramatically to the lowest at 50 ℃.However,the changes of the myofibril from silver carp basically kept the same at the range of 0 to30 ℃,and then reached a low point at 40 ℃.The thermal denaturation and SDS-PAGE results displayed that the myofibrillar of the silver carp denatured at 40 ℃ and the mixed meat and chicken protein denatured at 50 ℃.Above results indicated that the accumulation of myosin heavy chains led to changes in the molecular conformation of the protein at denatured temperature during the heating process.In addition,there were differences between the blended protein and single protein,which improved gel properties of blended protein by combining the advantage of single protein.

关 键 词：肌原纤维蛋白质 鲢鱼 鸡胸肉 混合肉 热变性温度 

分 类 号：TS251.1[轻工技术与工程—农产品加工及贮藏工程]