Method for producing a concentrate of eicosapentaenoic and docosahexaenoic acids

Concentrate of esters of EPA and DHA obtained by:

• a) contacting crude or refined marine oil with at least one alkali and water at a temperature no higher than 100° C. to obtain mixture comprising saponified marine oil;
• b) contacting the saponified mixture with at least one organic solvent to form a refined phase comprising alkaline salts of fatty acids and an extracted phase;
• c) separating the extracted phase from the refined phase;
• d) mixing the refined phase with an aqueous solution of an acid to form a non-aqueous phase comprising fatty acids and an aqueous phase;
• e) separating the aqueous phase of the non-aqueous phase;
• f) mixing the separated non aqueous phase with an alcohol and an esterification catalyst at a temperature of at most 150° C. until an esterified mixture comprising esters of fatty acids is obtained;
• g) removing the catalyst from the esterified mixture to obtain the catalyst-free esterified mixture;
• h) removing any solvents from the catalyst-free esterified mixture to obtain esters of fatty acids, and
• i) distilling the esters of fatty acids in a short path distillation column at a temperature of at most 180° C. and a pressure of less than 1 mbar to obtain a concentrate comprising esters of EPA and DHA,
• wherein the total content of esters of EPA and DHA is at least 40% by weight of the concentrate, the content of trans isomers of the concentrates is equal to or lower than the content of trans isomers of the crude or refined marine oil, the concentrates have neutral organoleptic properties and oxidative stability, their content of PCBs is lower than 90 ng/g and their content of dioxins and furans is at most 2 pg/g of concentrate.