Production of triglycerides enriched in long-chain n-3 polyunsaturated fatty acids from fish oil

Processes that combine enzymic and physical techniques have been studied for concentrating and separating eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil. Candida rugosa lipase was used in hydrolysis reactions to concentrate these acids in the glyceride fraction. By controlling the degree of hydrolysis, two products have been obtained, one enriched in total n-3 (similar to 50%), the other enriched in DHA and depleted in EPA (DHA similar to 40%, EPA similar to 7%). The glyceride fraction from these reactions was recovered by evaporation and converted back to triglycerides by partial enzymic hy: drolysis, followed by enzymic esterification. Both reactions were carried out with Rhizomucor miehei lipase. DHA-depleted free fatty acids from a C. rugosa hydrolysis were fractionated to increase the EPA level (similar to 30%) and re-esterified to triglycerides by reaction with glycerol and R. miehei.