Long chain monounsaturated fatty acid composition and method for the production thereof
View Patent ↗In one aspect, the present invention is directed to a method for obtaining an enriched composition of long chain monounsaturated fatty acids from an oil composition, typically a fish oil composition, comprising both long chain monounsaturated fatty acids and long chain polyunsaturated fatty acids. In another aspect, the present invention is directed to a composition comprising at least 70% by weight of long chain monounsaturated fatty acids.
1. A method for obtaining an enriched composition of C 20 -C 22 long chain monounsaturated fatty acids comprising the steps of:
a) mixing an oil composition comprising C 20 -C 22 long chain polyunsaturated fatty acids and at least 15% by weight C 20 -C 22 long chain monounsaturated fatty acids with (i) an organic solvent selected from the group consisting of C 1 -C 5 alcohols and ketones of the formula R 1 (C═O)R 2 wherein R 1 and R 2 are each independently C 1 -C 5 alkyl; and (ii) a lithium salt to form a mixed composition comprising the lithium salts of long chain monounsaturated fatty acids and the lithium salts of the long chain polyunsaturated fatty acids at 55° C. to 80° C.;
b) reducing the temperature of the mixed composition formed in step a such that the lithium salts of the long chain monounsaturated fatty acids form a precipitate; and
c) removing the precipitate to obtain an enriched composition of long chain monounsaturated fatty acids.
2. The method of claim 1 , wherein the oil composition is derived from fish, crustaceans, algae, plankton or higher plants.
3. The method of claim 1 , wherein the oil composition is comprised of a member selected from the group consisting of free fatty acids and fatty acid monoesters.
4. The method of claim 3 , wherein the fatty acid monoesters comprise ethyl esters.
5. The method of claim 1 , wherein the oil composition has been subjected to a prior fractionation step to reduce the concentration of at least one of saturated fatty acids and shorter chain fatty acids.
6. The method of claim 1 , wherein an additional base is added in step a.
7. The method of claim 6 , wherein said additional base is potassium hydroxide.
8. The method of claim 1 , wherein the organic solvent is selected from the group consisting of ethanol and acetone.
9. The method of claim 1 , wherein the solvent is added in an amount of between 0.5 and 8 liters per kilogram of oil composition.
10. The method of claim 1 , wherein the lithium salt is selected from the group consisting of lithium carbonate, lithium bicarbonate and lithium hydroxide.
11. The method of claim 10 , wherein the lithium salt comprises lithium hydroxide.
12. The method of claim 1 , wherein the lithium salt is added in an amount of between 5 and 70 grams, calculated as lithium, per kilogram of oil composition.
13. The method of claim 1 , wherein the mixed composition is cooled to 10° C. or less in step b.
14. The method of claim 1 , wherein the oil composition is a fish oil composition.
15. The method of claim 1 , wherein the content of persistent organic environmental pollutants, as measured by the content of PCBs, is reduced by more than 90% compared to the starting oil composition.
16. A composition comprising at least 70% by weight C 20 -C 22 long chain monounsaturated fatty acids.
17. The composition of claim 16 wherein said composition comprises at least 80% by weight C 20 -C 22 long chain monounsaturated fatty acids.
18. The composition of claim 16 wherein said composition comprises free C 20 -C 22 long chain monounsaturated fatty acids.
19. The composition of claim 16 wherein said composition comprises monoesters of C 20 -C 22 long chain monounsaturated fatty acids.
20. The composition of claim 16 wherein said composition comprises triglycerides of C 20 -C 22 long chain monounsaturated fatty acids.