面包酵母酶解液中水不溶性沉淀的形成机理  

The Research on the Formation Mechanism of Water Insoluble Precipitate in Baker's Yeast Hydrolyzate

作　　者：胡庆玲[1] 丛懿洁[1] 崔春[1] 赵谋明[1] 

机构地区：[1]华南理工大学轻工与食品学院

出　　处：《食品与发酵工业》2012年第3期58-61,共4页Food and Fermentation Industries

基　　金："十二五"国家科技支撑计划项目(食品香料香精制备关键技术研究及产业化)

摘　　要：以导致面包酵母木瓜蛋白酶酶解液浑浊的沉淀物质为研究对象,分析了该沉淀物质的基本化学组成、氨基酸组成、分子量分布以及在不同溶剂和不同pH值缓冲液中的溶解度,从而探讨了该沉淀物的形成机理。研究结果表明,沉淀物质(以干基计)主要组成成分为:蛋白质62.00%、总糖22.80%和灰分15.50%;分离沉淀前后酶解液的分子量分布结果表明,有分子量小于1000 u的肽分子参与沉淀物的构成;氨基酸分析显示,沉淀物质中的疏水氨基酸含量占46%,高于酶解液中的32.03%,说明疏水作用可能是该沉淀物形成的主要推动力;沉淀溶解度定性与定量测定显示沉淀在水和氨水中微溶,且等电点在pH6.5附近。Using the precipitation contributing to turbidity of the baker＇s yeast hydrolysates as the object,we analyzed the precipitation＇s basic composition,amino acid composition,molecular weight distribution,solubility in different solvents and buffer solution of different pH,and also discussed the formation mechanisms of the precipitation.Results showed that the precipitation was mainly composed of crude protein at 62.00%,sugar totaled 28.80% and ash at 15%;the molecular weight distribution of the hydrolysates before and after the precipitation＇s removal showed that peptides whose molecular weight were less than 1 000 u acontributed to the precipitation＇s composition.Amino acid analysis revealed that hydrophobic amino acid content of the precipitation was 46%,which was higher than that of the hydrolyzate at 32.03%.Then it illustrated that the hydrophobic interaction force may be the major force to drive the precipitation＇s formation.The qualitative and quantitative tests of precipitation＇s solubility showed that the precipitation was slightly soluble in water and ammonia,and the isoelectric point of the precipitation was near pH 6.5.

关 键 词：面包酵母 沉淀 疏水氨基酸 肽分子量 溶解性 

分 类 号：TS201.25[轻工技术与工程—食品科学]