pH偏移结合加热处理对大豆分离蛋白乳化特性的影响  

The Influence of Emulsify Properties of Soybean Protein Isolate Induced by pH-shifting Combined with Heating Treatment

作　　者：耿蕊[1] 卢岩[1] 孔保华[1] 刘骞[1] 吕红 

机构地区：[1]东北农业大学食品学院,哈尔滨150030 [2]哈尔滨轻工业学校,哈尔滨150076

出　　处：《中国食品学报》2016年第1期173-180,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家"863计划"项目(2013AA102208-2)

摘　　要：探讨p H偏移结合加热处理对大豆分离蛋白乳化特性的影响。将大豆分离蛋白经酸性(p H 1.5)结合加热(50℃和60℃)处理0,1,3,5 h,然后恢复中性条件,测定处理前后大豆分离蛋白的乳化活性和乳化稳定性、ζ电势、浊度、粒径分布以及蛋白聚合物变化趋势。研究结果表明,p H 1.5偏移结合加热处理条件下,大豆分离蛋白的乳化活性显著提高(P<0.05);虽然乳化稳定性在处理1 h后显著提高(P<0.05),但是长时间的处理会降低乳化稳定性(P<0.05);ζ电势和浊度随着处理时间的延长逐渐增强(P<0.05),可以推测内部疏水基团暴露;粒径分布发生显著的后移,表明加热导致大豆分离蛋白聚集程度不断加剧;SDS-PAGE凝胶电泳表明,大豆分离蛋白产生非二硫键的共价聚集。结论:p H偏移结合加热处理在一定程度上改善大豆分离蛋白的乳化性。This study mainly investigated the changes of emulsify capability of soybean protein isolate（SPI） induced by pH shifting combined with heating treatment. SPI was treated 0, 1, 3, 5 h by acidic pH shifting（pH 1.5） combined with heating（50 ℃ and 60 ℃） treatment, followed by refolding at neutral pH. The EAI and ESI, ζ-potential,turbidity, 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 increased after 1h（P〈0.05）, however, the ESI decreased for longer heating time（P〈0.05）. The ζ-potential and turbidity increased significantly（P〈0.05） as time extending, which indicated that more hydrophobic groups were exposed. The particle size distributions showed that the aggregation degree was intensified by heating treatment. The SDS-PAGE patterns showed that non-disulphides linkage between proteins was produced by protein aggregation. These results showed that function characteristics of SPI were changed via p H shifting combined with heating treatment.

关 键 词：大豆分离蛋白 pH偏移 加热 乳化特性 

分 类 号：TS201.21[轻工技术与工程—食品科学]