Method for extracting microbial oil

Abstract

The invention provides a method for extracting microbial oil, which comprises the following steps: (1) allowing an oil-producing microbial strain to ferment and obtaining fermentation liquor; (2) regulating the pH value of the fermentation liquor obtained by the step (1) to 3.5 to 4.5, and allowing microbes to autolyze; (3) extracting by adding an extracting solvent into the fermentation liquor obtained by the step (2), and collecting upper mixed oil; (4) extracting again by adding the extracting solvent into the lower solution obtained by the extraction and separation in the step (3), and collecting upper mixed oil; and (5) mixing the upper mixed oil obtained by the step (3) and the upper mixed oil obtained by the step (4), distilling, recovering the extracting solvent and obtaining the microbial oil product. The method can extract the oil in the cells of microbes effectively, has high oil extraction rate and high oil extraction efficiency, makes process simple and is favorable for large-scale production.

Description

Technical field [0001] The invention relates to a method for extracting microbial oil. Background technique [0002] Polyunsaturated fatty acids (PUFA) play a vital role in human growth, development and health. To maintain the normal functions of various tissues, the human body must ensure adequate amounts of various fatty acids. If they are lacking, it will cause a series of symptoms, including growth retardation, abnormal skin scales, intellectual disability, etc. For example, Docosahexaenoic acid (DHA), as an important PUFA, has a very significant role in enhancing memory, thinking ability, and improving intelligence. When there is a long-term lack of DHA in the diet, it will have adverse effects on people's intelligence, memory and thinking abilities. Population epidemiological studies have found that people with high DHA content in their bodies have stronger psychological endurance and higher intellectual development indexes. [0003] At present, the technology of us...

AI Technical Summary

Problems solved by technology

[0003] At present, the technology of using microbial fermentation to produce polyunsaturated fatty acid oil is very mature, but there are still some problems in the extraction process of microbial oil, which needs to be improved

[0004] The patent application of CN101133144A discloses the use of plant seeds and organisms to mix and dry to obtain oils containing unsaturated fatty acids by pressing. The main problem of this process is that the fatty acids in the plant seeds themselves reduce the content of target fatty acids. The outer wall of somatic cells is relatively hard, and the actual oil extraction effect is not optimistic

[0005] The patent application of CN1217029A discloses using the method of preparing oil containing polyunsaturated fatty acids from pasteurized biomass, and then in the process of oil extraction in the later stage, by granulation, drying, and using organic solvents to extract oil, while This process takes a lot of time, and uses high temperature sterilization and drying processes, which is not conducive to the preservation of polyunsaturated fatty acids

[0006] The patent application of CN101195813A discloses a process of extracting grease by using high-pressure homogeneous crushing of cell walls. This process requires the use of high pressure of 120 MPa to crush microbial cells many times. The energy consumption required for production is huge, which is not conducive to large-scale production