【作者】 陈静；

【导师】 张和平；

【作者基本信息】 内蒙古农业大学 ， 农产品加工及贮藏工程， 2004， 硕士

【摘要】 本试验采用酶-膜反应器技术连续化水解婴儿配方乳中的蛋白质。实验通过对来源安全、丰富的三种蛋白酶的比较筛选，采用pH－drop的方法最终确定以胰蛋白酶为水解用酶，对牛乳蛋白质进行改性研究；采用单因素实验设计方法，以水解液的5%三氯乙酸可溶性氨基氮为指标，选择确定胰蛋白酶作用于婴儿配方乳蛋白的最适温度40℃、最适pH8.0；采用三因素三水平正交旋转回归实验设计方法，以蛋白质的水解度为指标，选择确定胰蛋白酶水解婴儿配方乳蛋白的最适酶底比(E/S，w/w)1.84%、最适底物浓度(S，w/v) 4%、最适压力(P，MPa)为0.05MPa；使用SAS软件对三因素三水平正交旋转回归实验结果做回归分析，建立婴儿配方乳中蛋白质在酶－膜反应器中连续化水解的数学模型，其数学模型为Y＝36.4＋5.4162X1－8.20X2－0.6233X3＋0.7068X12＋0.5619X1X2＋0.7193X22－0.2886X3X1－0.0214X3X2＋0.0306X32；对婴儿配方乳蛋白水解液做理化指标的分析，包括水解液的电泳检测，蛋白质含量测定，以及可溶性氨基氮的测定，可以得出：水解前后蛋白含量有有明显的差异，乳蛋白在水解之后含量明显下降，尤其是酪蛋白，其中αs-酪蛋白水解掉90%以上，乳清中的β－乳球蛋白有部分的水解，水解液中可溶性氨基氮升高；对脱脂奶粉、婴儿配方奶粉、婴儿配方乳蛋白水解液的冻干粉进行动物消化实验，检测实验小鼠的胃液、肠液的5%TCA可溶性氨基氮含量，以及取小鼠进食1h的胃液做氨基酸分析，可以得出：婴儿配方乳经过一定程度的初步消化以后，其消化率有明显的提高。更多还原

【Abstract】 Milk protein from infant formulas was continuously hydrolyzed in an enzyme membrane reactor . After choosing three kinds of safe and abundant enzymes and comparing with each other, it was decided to use tyrpsin as hydrolyzing enzyme to modify the protein. And studied the follow variables during the CSTMR’s operation: optimum temperature，optimum pH，optimum enzyme substrate ratio(E/S，w/w)，optimum substrate concentration (S，w/v)，and optimum pressure(P, MPa). We finally chose temperature of 45℃,pH 8.0,E/S 1.84%,S 0.4%,and P 0.05MPa as the CSTMR’s optimum parameter. Through analyzing the result of orthogonality experiment, we get an analog equation to be used for practice. The analog equation is Y=36.4＋5.4162X1－8.20X2－0.6233X3＋0.7068X12＋0.5619X1X2＋0.7193X22－0.2886X3X1－0.0214X3X2＋0.0306X32.Also studied the physical and chemical properties of the hydrolysate, using some biochemical technologies, such as electrophoresis analysis, soluble amino nitrogen determent, and protein distribution etc. It was found that the hydrolysate had fewer proteins than the infant formula before being hydrolyzed and more soluble amino nitrogen. Especially the hydrolyate had much more fewer αs-casein and β-lactoglobulin. These all were helpful to prove that the hydrolyzed infant formula had improving digestibility and absorptivity and probably had more lower allergy. We also did the animal experiment to prove its high digestibility and absorptivity. The result was very notable.更多还原