Heat-induced inactivation mechanisms of Kunitz trypsin inhibitor and Bowman-Birk inhibitor in soymilk processing

详细信息    查看全文

• 作者：Yeming Chen ; Zhicun Xu ; Caimeng Zhang ; Xiangzhen Kong ; Yufei Hua
• 关键词：Soymilk ; NaCl ; Kunitz trypsin inhibitor (KTI) ; Trypsin inhibitor activity (TIA) ; Bowman-Birk inhibitor (BBI) ; Chymotrypsin inhibitor activity (CIA) ; Disulfide bond ; Protein aggregate ; Peptide bond cleavage
• 刊名：Food Chemistry
• 出版年：1 July, 2014
• 年：2014
• 卷：154
• 期：Complete
• 页码：108-116
• 全文大小：1873 K

文摘

Trypsin inhibitor activity (TIA) is an important antinutritional factor in soymilk. In this study, the effects of NaCl preaddition on TIA and the heat-induced TIA inactivation mechanisms were examined. The results showed that Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI) contributed 74% and 26% to raw soymilk TIA, respectively. The heat-induced quick KTI incorporation into protein aggregates was the reason for its quick TIA inactivation. The heat-induced slow cleavage of one BBI peptide bond was the reason for its slow TIA inactivation. Heat-induced protein aggregate formation had little effect on BBI inactivation owing to the fact that BBI and its degradation product tended to remain in the supernatant (197,000g, 1 h) in all conditions used in this study. NaCl could accelerate the KTI incorporation into protein aggregates and the cleavage of one BBI peptide bond, which supplied a simple and quick method for low TIA soymilk processing.