纳米粉碎对乳清浓缩蛋白及其微凝胶颗粒结构和界面性质的影响  

Influence of Nano Grinding on Structure and Interfacial Properties of Whey Protein Concentrate and Its Micro-gel Particles

作　　者：郭雅娴 李姿坤 张喜瑞 张满 梁彬 姬长建 孙婵婵 GUO Ya-xian;LI Zi-kun;ZHANG Xi-rui;ZHANG Man;LIANG Bin;JI Chang-jian;SUN Chan-chan(College of Life Sciences,Yantai University,Yantai 264003,Shandong,China;College of Food Engineering,Ludong University,Yantai 264001,Shandong,China;Department of Physics and Electronic Engineering,Qilu Normal University,Jinan 250200,Shandong,China)

机构地区：[1]烟台大学生命科学学院,山东烟台264003 [2]鲁东大学食品工程学院,山东烟台264001 [3]齐鲁师范学院物理与电子工程学院,山东济南250200

出　　处：《食品研究与开发》2022年第14期23-31,共9页Food Research and Development

基　　金：国家自然科学基金青年科学基金项目(32101904);山东省自然科学基金青年基金项目(ZR2020QC219);山东省自然科学基金博士基金项目(ZR2019BC036)。

摘　　要：该文研究纳米粉碎对乳清浓缩蛋白(whey protein concentrate,WPC)及乳清浓缩蛋白微凝胶颗粒(whey protein concentrate micro-gel particles,WPM)粒径、分子量、游离巯基含量和内源性荧光光谱的影响,探究蛋白质多尺度结构的变化对WPM稳定乳液的微流变特性、贮藏稳定性和微观形貌的影响,以表征乳清浓缩蛋白界面性质的变化规律。研究结果表明:纳米粉碎预处理可以显著降低乳清浓缩蛋白的粒径并增强粒径分布的集中程度。纳米粉碎预处理后,蛋白质分子量并无明显差异,但是游离巯基含量明显减少,证明了大量分子内二硫键的形成;内源性荧光光谱结果显示WPC的最大吸收波长由333 nm红移至339 nm处,说明内埋的疏水性基团暴露,表面疏水性增强。经纳米粉碎和微粒化处理后,sWPM-8h乳液具有最强的黏性和弹性、较小的固液平衡值、最小的流动性指数和最高的贮藏稳定性。综上,纳米粉碎可以改善乳清浓缩蛋白的界面性质。This paper investigated the influence of nano grinding on particle size,molecular weight,free sulfhydryl content,and endogenous fluorescence spectrum of whey protein concentrate(WPC)and whey protein concentrate micro-gel particles(WPM),as well as the effect of the changing protein multi-scale structure on the micro-rheological properties,storage stability,and microstructure of the emulsion stabilized by whey protein concentrate and WPM,to characterize the change rule of the interfacial properties of WPC.The results showed that nano grinding could significantly reduce the particle size of WPC and strengthen the concentration of particle size distribution.The molecular weight of proteins showed no significant variation after the nano grinding.However,the content of free sulfhydryl groups obviously decreased,indicating the formation of a large number of intramolecular disulfide bonds.According to the endogenous fluorescence spectra,the maximum absorption wavelength of WPC shifted from 333 nm to 339 nm,suggesting the exposure of embedded hydrophobic group and the enhancement of surface hydrophobicity.Compared with the other emulsions,the sWPM-8h emulsion had the strongest elasticity index and macroscopic viscosity index,the lower solid-liquid equilibrium value,the lowest fluidity index and the highest storage stability after nano grinding and microparticulation treatment.All the results indicated that nano grinding could improve the interface properties of whey protein concentrate.

关 键 词：纳米粉碎 乳清浓缩蛋白 乳清浓缩蛋白微凝胶颗粒 结构 界面性质 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]