乳清分离蛋白-壳聚糖复合颗粒的构建及其微观结构表征  

Construction and Microstructural Characterization of Whey Protein Isolate-Chitosan Composite Particles

作　　者：庞志花 孙梦雅 李博睿 刘萍[1] 李梦飞 陈存社[1] 刘新旗[1] PANG Zhihua;SUN Mengya;LI Borui;LIU Ping;LI Mengfei;CHEN Cunshe;LIU Xinqi(School of Food and Health,Beijing Technology and Business University,Beijing 100048,China)

机构地区：[1]北京工商大学食品与健康学院,北京100048

出　　处：《食品科学技术学报》2023年第1期99-105,共7页Journal of Food Science and Technology

基　　金：国家自然科学基金资助项目(31901817)。

摘　　要：为研究蛋白-多糖复合颗粒的形成条件,特别是工艺条件对构建其核壳结构的影响,以乳清分离蛋白(WPI)和自然界唯一带正电荷的多糖——壳聚糖(CS)为原料,构建蛋白为核,多糖为壳的结构化复合颗粒,针对颗粒的形成条件及影响因素进行研究,并对所形成颗粒的粒径、电位及微观结构进行表征。pH值和盐离子浓度是二者发生复合作用的重要条件。实验结果表明,当盐离子浓度为0、pH值达到5.47时,体系浊度最大,达98.34%,二者的复合程度最高。在该条件下制备复合颗粒,研究混合方式、处理温度和剪切处理对复合颗粒的组成及粒径的影响,结果表明:热-混方式(先对蛋白进行热处理再与壳聚糖混合)与混-热方式(先将蛋白和壳聚糖混合再进行热处理)形成复合微粒的组成没有明显差异,但热-混形成颗粒的粒径更小且电位绝对值更大,说明颗粒稳定性更高;75、85、95℃热处理条件下,复合颗粒中蛋白质和多糖的组成基本一致,但温度越高颗粒粒径越大,电位绝对值越小;剪切处理可有效降低颗粒粒径。复合颗粒的共聚焦扫描图像结果显示:75℃热处理的复合颗粒表现出明显的蛋白、多糖荧光共定位现象。研究表明,75℃热处理、热-混方式、辅助高速剪切可以制备具有完整“核壳”结构、粒径为744.5 nm的复合微粒。To study the formation conditions of protein and polysaccharide composite particles,especially the effect of processing conditions on the construction of their core-shell structure,whey protein isolate(WPI)and chitosan(CS),the only naturally positively charged polysaccharide,were used to form composite particles with protein as core and polysaccharide as shell.The conditions of particle formation and the influencing factors were investigated,and the particle size,potential and microstructure of the formed particles were characterized.The pH value and salt ionic strength were important factors for composite reactions of the two substance.The results showed that when the salt ionic strength was 0 and the pH value reached 5.47,the turbidity of the system reached maxium,which was 98.34%and complexation of the two substance reached the highest degree.Therefore,composite particles prepared at these conditions were used to study the effect of mixing mode,treatment temperature and shear treatment on the composition and particle size of composite particles.The results showed that there was no significant difference in the composition of the composite particles formed by heat-mixing(heat treatment of protein followed by mixing with chitosan)and heat-mixing(mixing of protein and chitosan followed by heat treatment),but the particle size of the particles formed by heat-mixing was smaller and the absolute value ofξpotential was larger,indicating that the particles were more stable.There was no significant difference in the proportion of protein and polysaccharide in the composite particles under heat treatment conditions of 75,85,95℃,but the higher temperature,the larger particle size and the smaller absolute value of the potential.The particle size could be effectively reduced by shear treatment.The confocal laser scanning microscopy showed that the composite particles formed at 75℃exhibited a clear co-localization of protein and polysaccharide fluorescence.The results showed that complete core-shell structured composit

关 键 词：乳清分离蛋白 壳聚糖 复合颗粒 粒径 Ζ电位 微观结构 

分 类 号：TS201.3[轻工技术与工程—食品科学]