控制酶解黄粉蛋白制备富含“条件必需氨基酸”rn—谷氨酰胺(Gln)活性肽营养液的研究rn(Ⅱ)Gln活性肽的制备工艺和最佳工艺条件的确定

摘要

The process and optimum conditions of a bioactive glutamine oligopeptide preparation were studied.Corn protein was hydrolyzed by prozyme A and pepsin incessantly.The conditions for prozyme A were pH8.5,［s］2%,［E］90000units/100g corn protein,DH10,temperature40℃;the conditions for pepsin were pH2.0,［E］20000units/100g corn protein,16h,temperature 37℃.The hydrolysate was separated by ultrafilter technology(COMW 5000),and then condensed by reverse osmosis(10Kg/cm2,room temperature,2h).The ratios of effective glutamine to total amino acids and to total glutamine in the end product were 18.16±2.6%and 84.71±2.15%,respectively.The protein yield was 20.25±2.41%.ln addition,reductants had no obvious effect to the hydrolysis of corn protein.Dates also showed that homogenization(25MPa)improved the enzymatic reaction.%确定了Gln活性肽的水解用酶和最佳酶解条件，采用复合酶A和胃蛋白酶两次酶解工艺制备Gln活性肽，复合酶A的选用条件为pH8.5、［S］2%、［E］9万u/100g黄粉、DH10、温度40℃；胃蛋白酶的条件为pH2.0、［E］2万u/100g黄粉、16h、温度37℃。酶解液通过超滤(COMW5000)、反渗浓缩(10kg/cm2，常温2h)，最后产品有效Gln组成(有效Gln占总氨基酸的百分比)为18.16±2.6%，有效Gln占总Gln的84.71±2.15%，总氮得率20.25±2.41%。本文提出酶解之前对黄粉蛋白液进行均质处理，均质压力25MPa，并发现还原剂对酶解过程没有明显的促进作用。