碱性蛋白酶Alcalase凝固豆乳的物性特征

Texture properties of soymilk coagulated by an alkaling proteinase-Alcalase

在Alcalase凝固豆乳过程中pH下降程度小于0.2,SDS-PAGE电泳表明,大豆蛋白质各亚基在凝固过程中均降解为8～14kDa的肽段,说明大豆蛋白的部分降解是Alcalase凝固豆乳的根本原因。对Alcalase与盐类凝固剂氯化镁和氯化钙凝固豆乳的主要流变学性质比较发现,Alcalase凝固豆乳的硬度比盐类凝固剂大,凝胶强度比盐类凝固剂低,粘附性比盐类凝固剂高10倍以上,使凝胶较粘,乳清不易排出。

During the process of soymilk coagulation by AIcalase, the milk pH value dropped by 0.2, and all the subunits of soy protein were hydrolyzed to 8-14 kDa peptides, indicating that the main reason for the coagulation by Aicalase was the partial degradation of the peptide chains. The comparative tests of the rheological properties between Alcalase and saline coagulants （Magnesium Chloride and Calcium Chloride） showed that the hardness of Alcalase-induced soy coagulum was higher than that of saline coagulants, while the fracturability （Gel Strength） was lower. The adhesiveness of Alcalase-induced soy coagulum was more than 10 times higher than that of the saline group, which gave a viscous gel and the whey of it was not easy to drain.