Method for producing composite polyunsaturated fatty acid oil by using schizochytrium sp.

Abstract

The invention relates to the field of microbial oils, in particular to a method for producing a composite polyunsaturated fatty acid oil by using schizochytrium sp.. The method comprises the steps that the schizochytrium sp. is subjected to fermentation culture; bacteria after fermentation culture are resuspended with water, and cellulase and neutral protease are added for enzymolysis; an enzymatic hydrolyzate is mixed with n-hexane, shaking extraction and centrifugation are conducted, an n-hexane phase is collected, concentration under reduced pressure is conducted to remove the n-hexane, anddrying is conducted to obtain an oil; the oil is subjected to first-stage crystallization by means of a freezing crystallization technique, the liquid oil is subjected to second-stage crystallization, and cold filtration is conducted to obtain the liquid oil after secondary crystallization; the liquid oil is deacidified and decolorized. The method has the advantages that by regulating fermentation conditions and conducting concentration processing on polyunsaturated fatty acids, the content of eicosapentaenoic acid in the schizochytrium sp. is successfully increased to 12% or above, and the produced oil is rich in docosahexaenoic acid, docosapentaenoic acid and eicosapentaenoic acid and is a novel oil product capable of replacing the polyunsaturated fatty acids from fish oils.

Description

technical field [0001] The invention relates to the field of microbial oils, in particular to a method for producing complex polyunsaturated fatty acid oils by utilizing Schizochytrium algae. Background technique [0002] Currently commercially available ω-3 polyunsaturated fatty acids (PUFAs) are mainly derived from marine fish. Fish oil as a source is seriously affected by fishy odor and stability, which limits its use as food additives and food accessories. Global fish resources have tended to decrease due to overfishing, and the increasingly scarce marine fish oil is difficult to meet people's growing demand for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In addition, the supply and quality of fish oil are greatly affected by seasonal and weather changes, and marine pollution caused by toxic impurities, heavy metals and organic matter also limits the further development of fish oil-derived PUFAs. The high market price of ω-3PUFAs makes many potential app...

AI Technical Summary

Problems solved by technology

[0004] At present, under ordinary fermentation conditions, the DHA content in Schizochytrium oil reaches more than 35%, while the EPA content is only about 0.5% to 1.0%. The EPA content is far lower than the EPA content in fish oil, and it is difficult to develop compound PUFAs products.