Pouw M, Gruppen H
Department of Food Science, Food and Bioprocess Engineering Group, Wageningen Agricultural University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
J Agric Food Chem. 1998 Jan 19;46(1):281-285. doi: 10.1021/jf970506+.
The inactivation of trypsin inhibitors (TIs) in soy flour exhibits a two-phase inactivation behavior. It is sometimes assumed that this behavior is caused by a difference in the heat stabilities of the Kunitz soybean trypsin inhibitor (KSTI) and the Bowman-Birk inhibitor (BBI). Kinetics studies with KSTI and BBI in soy flour showed that this two-phase inactivation behavior of TIs could not be explained by the difference in the heat stabilities of KSTI and BBI. Inactivation of KSTI and BBI in an aqueous solution and in a starch matrix followed a first-order reaction. KSTI and BBI in a starch matrix with added cysteine showed a two-phase inactivation behavior. The existence of thiols in soy flour seems to be responsible for the two-phase inactivation of TIs in soy flour. It is suggested that TIs in soy flour are inactivated by sulfhydryl-disulfide interchange during the first inactivation phase and by heat during the second phase.
大豆粉中胰蛋白酶抑制剂（TI）的失活表现出两相失活行为。有时认为这种行为是由库尼茨大豆胰蛋白酶抑制剂（KSTI）和鲍曼-伯克抑制剂（BBI）热稳定性的差异引起的。对大豆粉中KSTI和BBI的动力学研究表明，TI的这种两相失活行为不能用KSTI和BBI热稳定性的差异来解释。KSTI和BBI在水溶液和淀粉基质中的失活遵循一级反应。添加半胱氨酸的淀粉基质中的KSTI和BBI表现出两相失活行为。大豆粉中硫醇的存在似乎是大豆粉中TI两相失活的原因。有人提出，大豆粉中的TI在第一个失活阶段通过巯基-二硫键交换失活，在第二个阶段通过加热失活。
