Extraction and winterization of lipids from oilseed and microbial sources
View Patent ↗A process for purifying a lipid composition having predominantly neutral lipid components having at least one long chain polyunsaturated fatty acid is disclosed. The process employs contacting the lipid composition with a polar solvent, such as acetone, wherein the solvent is selected such that contaminants are less soluble in the solvent than is the long chain polyunsaturated fatty acid. The process is typically conducted at cooler temperatures, including about 0° C. Upon precipitation of the contaminants from the lipid composition, a separation is conducted to remove the precipitated material from the lipid composition. The long chain polyunsaturated fatty acids can include ARA, DPA, EPA, and/or DHA. The process of the present invention effectively winterizes lipid compositions, thereby reducing the tendency of such compositions to become hazy.
1. A process for recovering a lipid composition comprising predominantly neutral lipid from a biomass, wherein the biomass comprises cellular debris, at least one long chain polyunsaturated fatty acid (LCPUFA) and at least one other compound, the process comprising the steps:
(a) contacting the biomass with a nonpolar solvent to recover lipid in an extraction process;
(b) processing the lipid composition by at least one step selected from the group consisting of refining the lipid composition, bleaching the lipid composition, and deodorizing the lipid composition and combinations thereof;
(c) adding a polar solvent to the lipid composition;
(d) cooling the polar solvent and lipid composition to selectively precipitate at least one other compound; and
(e) separating the precipitated other compound from the lipid composition.
2. The process of claim 1 , wherein the step of processing the lipid composition comprises processing the lipid composition by two or more steps selected from the group consisting of refining the lipid composition, bleaching the lipid composition, and deodorizing the lipid composition.
3. The process of claim 1 , wherein the step of processing the lipid composition comprises refining the lipid composition, bleaching the lipid composition and deodorizing the lipid composition.
4. The process of claim 1 , wherein the step of processing the lipid composition is conducted after the step of cooling of the polar solvent and lipid composition.
5. The process of claim 1 , wherein the LCPUFA is obtained from a source from the group consisting of Schizochytrium biomass, Thraustochytrium biomass and Crypthecodinium cohnii biomass and oilseeds from genetically modified plants containing genes from Schizochytrium or Thraustochytrium.
6. The process of claim 1 , wherein the LCPUFA is docosahexaenoic acid (DHA).
7. The process of claim 1 , wherein the at least one other compound comprises at least one compound selected from the group consisting of trisaturated glycerides, phosphorus-containing materials, wax esters, saturated fatty acid containing sterol esters, sterols, squalene, and hydrocarbons.
8. The process of claim 1 , wherein the at least one other compound comprises at least one compound selected from the group consisting trisaturated glycerides of lauric (C 12:0), myristic (C14:0), palmitic (C16:0) and stearic (C18:0) fatty acids and mixtures thereof.
9. The process of claim 1 , wherein the at least one other compound results in the formation of haze when present in the initial concentration in the initial lipid composition of step (b).
10. The process of claim 1 , wherein the nonpolar solvent is hexane.
11. The process of claim 1 , wherein most of the nonpolar solvent is removed from the lipid composition.
12. The process of claim 1 , wherein the nonpolar solvent after removing most of the nonpolar solvent from the lipid composition is from about 0 to about 4 weight percent of the lipid composition.
13. The process of claim 1 , wherein the nonpolar solvent after removing most of the nonpolar solvent from the lipid composition is from about 1 to about 4 weight percent of the lipid composition.
14. The process of claim 1 , wherein the polar solvent and the lipid composition in step (c) are kept in contact for about 0.5 to about 12 hours.
15. The process of claim 1 , wherein the polar solvent and the lipid composition in step (c) are kept in contact for about 2 to about 6 hours.
16. The process of claim 1 , wherein the polar solvent and the lipid composition in step (c) are kept in contact for about 5 hours.
17. The process of claim 1 , wherein the polar solvent is acetone.
18. The process of claim 1 , wherein step (e) separating the precipitated other compound from the lipid composition is selected from the group consisting of centrifugation, filtering and a combination thereof.
19. The process of claim 1 , wherein step (e) separating the precipitated other compound from the lipid composition is by filtering.
20. The process of claim 1 , wherein said cooling of the polar solvent and lipid composition to selectively precipitate at least one other compound occurs at a temperature that the desirable LCPUFAs are soluble in the polar solvent, and the undesirable compounds are not soluble in the polar solvent.
21. A process for recovering a lipid composition comprising predominantly neutral lipid from a biomass, wherein the biomass comprises cellular debris, at least one long chain polyunsaturated fatty acid (LOPUFA) and at least one other compound, the process comprising the steps:
(a) contacting the biomass with a nonpolar solvent to recover lipid in an extraction process;
(b) processing the lipid composition by at least one step selected from the group consisting of refining the lipid composition, bleaching the lipid composition, and deodorizing the lipid composition;
(c) adding a polar solvent to the lipid composition;
(d) cooling the polar solvent and lipid composition to selectively precipitate at least one other compound; and
(e) filtering the precipitated other compound from the lipid composition.