Method for preparing diglyceride by enzymatically catalyzing glycerol by supercritical CO2 system

Abstract

The invention discloses a method for preparing diglyceride by enzymatically catalyzing glycerol by a supercritical CO2 system. Diglyceride (Diglyceride, DAG) is a natural ingredient of oil, has the content of about 5 percent, is an ingredient with stronger function in natrual oil and can be divided into two kinds of 1, 2-DAG and 1, 3-DAG according to different combination positions of acyl and glycerol hyroxyl, wherein the active function of the 1, 3-DAG is better. In recent years, by taking the natural oil as a raw material, the method for preparing the DAG comprises a glycerolysis method, a hydrolysis method, a hydrolysis-esterification combined method and the like. At present, the glycerolysis method is mainly adopted, but has low reaction yield and has little 1, 3-DAG content. In a supercritical state, a CO2 fluid simultaneously plays the roles of a solvent and a catalyst and can efficiently avoid the phenomena of catalyst positioning, inactivation and the like. In addition, moreimportantly, the CO2 fluid can prevent glycerolysis reverse reaction in the reaction environment. The diglyceride content in a product generated through the method is 70.2 percent, wherein the content of the 1, 3-DAG can reach 48.8 percent.

Description

Technical field: [0001] The invention relates to the field of edible oil processing, in particular to a method for preparing diglycerides by using carbon dioxide as a fluid and adopting lipase-catalyzed glycerolysis in a supercritical system. Background technique: [0002] With the improvement of people's living standards and the formation of bad living habits, obesity, cardiovascular disease, fatty liver and other wealthy diseases are becoming more and more common, which have seriously threatened human health. Diglycerides can not only improve the flavor of food and prolong the storage period, but also are the main additive of functional foods. It can reduce the accumulation of fat in the body and prevent and treat hyperlipidemia and related diseases. [0003] Diacylglycerol is abbreviated as diglyceride (DAG), which is obtained by esterification of glycerol and two fatty acids. It is a trace component in natural vegetable oils and an endogenous intermediate product of fat metabol...

AI Technical Summary

Problems solved by technology

[0004] The use of chemical solvents improves the reaction rate to a certain extent, but it cannot fundamentally change the phenomenon of low enzymatic conversion rate and target product yield; at the same time, from the perspective of industrial production, the safety is reduced and the cost is increased.