Patent ID: 9540306
Date: 2017-01-10
CPC Classifications: A23D,A23L,A61K,A61P,B01D,C07C,C11B,C11C

Claim:
1. A method of producing a highly unsaturated fatty acid or a highly unsaturated fatty acid ethyl ester with reduced contents of polychlorinated dibenzoparadioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar PCB (Co-PCBs), wherein the highly unsaturated fatty acid is eicosapentaenoic acid or dihomo-γ-linoleic acid, the method comprising the steps of: a) removing free fatty acids and environmental pollutants by thin-film distillation from a feedstock oil containing highly unsaturated fatty acids as constituent fatty acids; b) ethyl esterifying the highly unsaturated fatty acids present as constituent of fat or oil contained in the product of step (a); c) refining the product of step (b) by rectification and column chromatography, wherein a concentration of the highly unsaturated fatty acid ethyl ester in the sum of fatty acid ethyl esters is at least 80 area %.