以高酸值米糠油为原料,采用无溶剂体系酶法催化制备富含甘油二酯的米糠油.考察了脂肪酶种类及添加量,酯化剂种类,底物质量比,反应时间,反应温度对甘油二酯含量和游离脂肪酸残余量的影响.通过单因素试验和响应面试验,确定酶法催化酯化的最佳工艺条件为:固定化脂肪酶Lipozyme RM IM作为催化剂,油酸甘油一酯作为酯化剂,底物质量比0.25:1,反应温度56℃,反应时间5.75 h,脂肪酶添加量4.77%.在此条件下,产物中甘油二酯含量和游离脂肪酸残余量分别为27.61%和0.25%.%High acid rice bran oil was catalyzed to prepare rice bran oil rich in diacylglycerol(DAG) by lipase in a solvent -free system. The effects of lipase, esterification agent, mass ratio of substrate, reaction temperature, reaction time and lipase dosage on the content of DAG and the residual content of free fatty acid (FFA) were investigated. The reaction conditions were optimized by single factors experiment and response surface methodology as follows: immobilized Lipozyme RM IM used as a catalyst, glyceryl monooleate used as a esterification agent, mass ratio of substrate 0.25: 1, reaction temperature 56 ℃, reaction time 5.75 h and lipase dosage 4.77％. Under. the optimal conditions the content of DAG and residual content of FFA were 27.61％ and 0.25 ％, respectively.
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