超高压均质对大豆分离蛋白乳化特性的影响

The Changes of Emulsify Properties of Soybean Protein Isolate Induced by Ultra High Pressure Homogenization

主要探讨超高压均质处理对大豆分离蛋白乳化特性的影响。将大豆分离蛋白10%的水溶液经60、80、100、120 MPa高压均质处理,与原大豆分离蛋白作对比进行研究。测定处理前后大豆分离蛋白的乳化性和乳化稳定性、ζ电势、粒径分布以及蛋白聚物变化趋势。研究表明,经过高压均质处理的大豆分离蛋白的乳化性显著提高(p<0.05);乳化稳定性显著下降(p<0.05);ζ电势随着处理压力的增加逐渐减小后增加,可以推测内部疏水基团的暴露;粒径分布发生显著的后移,表明高压均质处理导致大豆分离蛋白聚集程度不断加剧;同时,SDS-PAGE凝胶电泳表明,大豆分离蛋白产生了共价聚集。上述结果表明,超高压均质处理能在一定程度上改善大豆分离蛋白的乳化性质。

The objective of this study was to investigate the effect of Ultra high pressure homogenization（UHPH）on emulsifying properties of isolated soy proteins（SPI）. 10 % SPI solution which were prepared by UHPH at 60,80,100,120 MPa was compared with the base SPI（untreated）. The EAI and ESI,ζ-potential,particle size distributions and the changes of protein aggregation were investigated. The results revealed that the EAI was increased significantly（p〈0.05）;the ESI was significantly decreased（p〈0.05）. The ζ-potential decreased to a minimum value and then increased with the increase of pressure,which indicated that more hydrophobic groups were exposed. The particle size distributions showed that the aggregation degree was intensified. The SDS-PAGE patterns showed that linkage between proteins was produced by protein aggregation. These results showed that function characteristics of SPI were changed by UHPH treatment.