体外氧化对牦牛肉肌原纤维蛋白凝胶保水性的影响  

Effect of in Vitro Oxidation on the Water Retention of Myofibrillar Proteins Gel from Yak Meat

作　　者：杨玲[1] 王兆丰 王静[1] 孙玉婧 徐盛燕 张娜 王春霖[1] 赵慧军[1] YANG Ling;WANG Zhaofeng;WANG Jing;SUN Yujing;XU Shengyan;ZHANG Na;WANG Chunlin;ZHAO Huijun(Department of Biological Engineering,Lanzhou Vocational Technical College,Lanzhou 730070,China;Jingning Inspection Testing Center of Food and Drug,Jingning 743400,China)

机构地区：[1]兰州职业技术学院生物工程系,甘肃兰州730070 [2]静宁县市场监督管理局食品药品检验检测中心,甘肃静宁743400

出　　处：《食品科技》2021年第12期123-129,共7页Food Science and Technology

基　　金：甘肃省青年科技基金项目(20JR10RA572)。

摘　　要：文章探讨氧化对牦牛肉肌原纤维蛋白结构的影响以及肌原纤维蛋白凝胶的保水机制。在Fenton反应体系中,测定蛋白质羰基含量、巯基含量、表面疏水性、内源性荧光光谱、紫外光谱、蛋白质凝胶质构特性和低场核磁共振弛豫时间及保水性(WHC)。结果表明,蛋白质氧化随着H_(2)O_(2)浓度的增加而增加(P<0.05);低场核磁共振结果显示凝胶中的固定水逐渐减少,但游离水含量逐渐增加(P<0.05);适量的H_(2)O_(2)产生·OH会影响肌原纤维蛋白中氨基酸残基,引起蛋白质二级和三级结构的变化(内源荧光强度、紫外吸收光谱和表面疏水性),导致蛋白质去折叠和疏水基团的暴露,蛋白质发生聚集。此外,在凝胶形成过程中被适度氧化的蛋白质凝胶具有良好的质地特征,显示出增加的硬度和WHC;然而,过度氧化会影响蛋白质凝胶中水的状态,导致WHC减少。The aim of this study was to investigate the effects of oxidation on the structure of yak meat myofibrillar proteins(MPs) and the water retention mechanism of MPs gel.In a Fenton reaction system,the changes in carbonyl group,total sulfydryl group contents,surface hydrophobicity,endogenous fluorescence spectrum,ultraviolet spectrum,protein gel structure,low field nuclear magnetic resonance (NMR) relaxation times and water holding capacity were analyzed.The result showed that protein oxidation increases (P<0.05) with hydrogen peroxide (H_(2)O_(2)) concentration.Low field nuclear magnetic resonance results showed that immobilized water in the gel gradually decreased but free water content gradually increased (P<0.05).An appropriate amount of H_(2)O_(2)produced ·OH that affects the amino acid residues in myofibrillar proteins,which induce changes in the secondary and tertiary structures,such as endogenous fluorescence intensity,UV absorption spectra,and surface hydrophobicity.These changes will cause proteins unfolding and exposure of the hydrophobic group.Proteins gel that is moderately oxidized during gel formation have good texture characteristics,showing increased hardness and WHC.However,excessive oxidation leads to change in water states of gel,leading to lower WHC.

关 键 词：氧化 肌原纤维蛋白 保水性 

分 类 号：TS251[轻工技术与工程—农产品加工及贮藏工程]