对豆浆和大豆浓缩蛋白(SPC)乳在不同温度(90~130℃)和时间(0~60 min)的热处理,并测定样品中硫胺素含量的变化。其中SPC蛋白乳中按照国标加入硫胺素进行营养强化。结果硫胺素在豆浆和SPC蛋白乳中的热破坏率都随加热温度的升高而增加。各温度下硫胺素含量减少90%所需要的时间(D值)也符合一级反应动力学的变化规律。根据阿累尼乌斯方程所得的反应动力学参数可以看出2种样品中硫胺素的热损失都符合一级反应动力学,但二者的动力学参数不相同,豆浆较SPC蛋白乳的热敏性较差。
Soymilk and Soybean protein concentrate(SPC)milk were heated under certain temperatures(90-130℃)and times(0-60 min).The thiamine content of the two samples was determined.The thiamine was putted in SPC milk according to GB14800-1994.Thermal degradation of thiamine in soymilk and SPC milk increased as the temperature increases.The decimal reduction time(D value),which was the time for 90% destruction of the thiamine at the specified temperature,was fitted the first-order reaction.According to the Arrhenius Equation,kinetic data on the thermal degradation of thiamine in soymilk and SPC milk were fitted with the first-order reaction but the kinetic parameters of the two samples were different.As compared to SPC milk,soymilk was less sensitive to thermal processing.