W/O乳液凝固剂对SPI冷凝胶流变特性与微观结构的影响  

Effect of W/O Emulsion Coagulants on Rheological Properties and Microstructure of Cold-set SPI Gels

作　　者：朱巧梅[1] 郦金龙[1] 范鑫[1] 殷丽君[1] 

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：《农业机械学报》2015年第2期240-246,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(31171648);'十二五'国家科技支撑计划资助项目(2012BAD34B03)

摘　　要：采用扫描电镜(SEM)、质地剖面分析(TPA)及动态流变技术研究卤水及不同油包水(W/O)乳液凝固剂对大豆分离蛋白(SPI)冷凝胶微观结构及流变特性的影响。流变结果表明,弹性模量(G')的变化高度依赖W/O乳液中的镁盐释放速度。随着反应时间的延长,G'值不断增大,与传统卤水相比,新型W/O乳液凝固剂延长了冷凝胶的凝固时间,在凝胶形成过程中,W/O乳液对镁盐起到了缓释作用。对比不同W/O乳液凝固剂发现,含有乳清分离蛋白(WPI)的乳液形成SPI冷凝胶的时间更长,而且弹性模量值更小。此外,电镜结果表明W/O乳液凝固剂能显著降低冷凝胶的硬度并改善蛋白凝胶的网络结构,使SPI冷凝胶具有更小的网孔孔隙和更加均匀的网状结构。Scanning electron microscopy （SEM）, texture profile analysis （TPA） and dynamic rheology technique were applied to investigate the effect of traditional bittern and different water in oil （W/O） emulsion coagulants on the rheological properties and microstructure of cold-set SPI gels. Rheological tests suggested that the development of the mechanical moduli （G＇） of these SPI gels was highly dependent on the release rate of magnesium salts from W/O emulsions. The values of G＇ in all cold-set SPI gels gradually increased with the extension of time and W/O emulsion coagulants prolonged the solidification time of cold-set SPI gels in comparison with traditional bittern coagulant. This could be attributed to the controlled-release properties of W/O emulsion coagulants. In addition, cold-set SPI gel prepared with W/O emulsion coagulant containing WPI exhibited a longer solidification time and a lower value of G＇ than W/O emulsions without WPI. Cold-set SPI gels induced by W/O emulsion coagulants had better mierostructure than that of traditional bittern coagulant as shown by SEM results, which elucidated that W/O emulsion coagulants could obviously decrease the strength of cold-set SPI gels and produce protein gels with smaller pores and more homogeneous network structure.

关 键 词：冷凝胶 油包水乳液 凝固剂 流变特性 微观结构 质构分析 

分 类 号：TS201.7[轻工技术与工程—食品科学]