超临界体系酶法催化甘油解制备甘油二酯的研究

Study on enzymatic synthesis of diacylglycerol by glycerolysis in supercritical system

对在CO2超临界体系酶法催化甘油解反应制备甘油二酯进行研究,考察了底物大豆一级油/甘油的摩尔比、反应温度、加酶量、加水量、时间和搅拌速度等因素对甘油二酯含量的影响。通过单因素与正交实验,确定了最优工艺条件为:大豆一级油与甘油摩尔比2∶1,反应温度65℃,加酶量2.5%,甘油含水量1%,反应时间7h,搅拌速度120r/min,得到反应产物中甘油二酯含量为70.2%,其中1,3-甘油二酯含量达56.2%。与常规甘油解相比,甘油二酯含量要高出7%左右,其中1,3-甘油二酯含量要高出5%左右,并且,时间减少2h左右。

The preparation of DG by enzymatic glycerolysis in the CO2 supercritical system was studied. The effect of substrate soybean oil/glycerin molar ratio,temperature,amount of enzyme,water content of glycerol, time and stirring speed on the preparation of DG were studied. Through the single factor and orthogonal tests, the optimum conditions were determined as follows： ubstrate molar ratio 2：1, temperature 65℃, amount of enzyme 2.5%,water content of glycerol 1%, time 7h, stirring speed 120r/min. The product content of DG were 70.2% ,of which 1,3-DG were 56.2%. Compared with the conventional glycerolysis,the content of DG were much more than 7%, of which 1,3-DG were much more than 5%,and time reduced about two hours.