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CN-121990903-A - Method for separating lauric acid from coconut oil and application

CN121990903ACN 121990903 ACN121990903 ACN 121990903ACN-121990903-A

Abstract

The invention relates to the technical field of substance extraction, and particularly discloses a method for separating lauric acid from coconut oil and application thereof. The method comprises the following steps of (1) carrying out primary micro-rectification, namely enabling the temperature of the top of the tower to reach 143-156 ℃ under the conditions of vacuum degree of 14-17mbar and heating rate of 5-10 ℃ per 10min, then carrying out intermittent reflux-extraction for 20-60min in a mode of collecting the rectifying component 15s-25s after 10s of each reflux, (2) carrying out crystallization and centrifugation, namely cooling and crystallizing residues in the tower, centrifuging, collecting liquid components, wherein the temperature of the thermal insulation and crystallization in the cooling and crystallization is 24-26 ℃, and (3) carrying out secondary micro-rectification, namely enabling the temperature of the top of the tower to reach 148-183 ℃ under the conditions of vacuum degree of 2-5mbar and heating rate of 1-5 ℃ per 10min, and then carrying out intermittent reflux-extraction for 20-60min in a mode of collecting the rectifying component 0.75-1.25ml after 0.5ml of each reflux. The method has low temperature control energy consumption and high product yield and purity.

Inventors

  • MU ZHISHEN
  • ZHANG LI
  • JI GUOZHI
  • WEN XINHUA
  • LI XIAOMIN

Assignees

  • 内蒙古蒙牛乳业（集团）股份有限公司

Dates

Publication Date
20260508
Application Date
20260130

Claims (10)

  1. 1. A method for separating lauric acid from coconut oil, which is characterized in that the coconut oil is hydrolyzed, and after separation, free fatty acid of the coconut oil is obtained, the following operations are sequentially carried out: (1) Primary micro-rectification: Carrying out primary micro-rectification on the coconut oil free fatty acid; The primary micro-rectification is carried out under the conditions that the vacuum degree is 14-17mbar, the temperature rising rate is 5-10 ℃ per 10min, the temperature at the top of a rectification column reaches 143-156 ℃, and then intermittent reflux-extraction is carried out for 20-60min according to the mode that 0.75ml-1.25ml of rectification component is collected after 0.5ml of reflux is carried out at 143-156 ℃; (2) Crystallizing and centrifuging: Cooling and crystallizing residues in the rectifying column after the step (1), centrifuging, and collecting liquid components; the method for cooling crystallization comprises cooling the residue to 24-26 ℃ under the conditions of stirring rotation speed of 250-350r/min and cooling rate of 1-5 ℃/30min, and then performing heat preservation crystallization; (3) And (3) secondary micro-rectification: carrying out secondary micro-rectification on the liquid component obtained in the step (2); The condition of the secondary micro-rectification is that under the conditions that the vacuum degree is 2-5mbar and the temperature rising rate is 1-5 ℃ per 10min, the temperature at the top of the rectifying column reaches 148-183 ℃, and then the intermittent reflux-extraction is carried out for 20-60min according to the mode that 0.75ml-1.25ml of rectifying component is collected after 0.5ml of reflux is carried out at 148-183 ℃.
  2. 2. The method for separating lauric acid from coconut oil according to claim 1, wherein, In the step (1), the condition of primary micro-rectification is that under the conditions of 14-15mbar of vacuum degree and 5-9 ℃ per 10min of heating rate, the temperature at the top of a rectification column reaches 154-155 ℃, and then intermittent reflux-extraction is carried out for 30-50min according to the mode of collecting 0.9ml-1ml of rectification component after 0.5ml per reflux at 154-155 ℃; In the step (2), the temperature-reducing crystallization method comprises the steps of reducing the temperature of the residues to 25-26 ℃ under the condition that the stirring rotating speed is 300r/min and the cooling rate is 1-2 ℃/30min, and then carrying out heat-preserving crystallization; In the step (3), the condition of the secondary micro-rectification is that under the conditions of 4mbar vacuum degree and 2-3 ℃ per 10min heating rate, the temperature at the top of the rectification column reaches 180-181 ℃, and then the intermittent reflux-extraction is carried out for 30-50min according to the mode of collecting 1ml of rectification component after 0.5ml per reflux at 180-181 ℃.
  3. 3. The method for separating lauric acid from coconut oil according to claim 2, wherein, In the step (1), the condition of primary micro-rectification is that under the conditions that the vacuum degree is 15mbar and the temperature rising rate is 5 ℃ per 10min, the temperature at the top of a rectifying column reaches 155 ℃, and then intermittent reflux-extraction is carried out for 30min at 155 ℃ in a mode of collecting 1ml of rectifying component after 0.5ml of reflux; In the step (2), the temperature-reducing crystallization method comprises the steps of reducing the temperature of the residues to 25 ℃ under the condition that the stirring rotating speed is 300r/min and the cooling rate is 2 ℃/30min, and then carrying out heat-preserving crystallization; In the step (3), the condition of the secondary micro-rectification is that under the conditions that the vacuum degree is 4mbar and the temperature rising rate is 2 ℃ per 10min, the temperature at the top of the rectification column reaches 180 ℃, and then the intermittent reflux-extraction is carried out for 30min at 180 ℃ in a mode of collecting 1ml of rectification component after each reflux of 0.5 ml.
  4. 4. A process for separating lauric acid from coconut oil as claimed in any one of claims 1-3 wherein in step (2) the time of incubation crystallization is 1-2 hours; And/or in the step (2), the centrifugation condition is 24-26 ℃,10000-15000r/min and 20-50min.
  5. 5. The method of separating lauric acid from coconut oil as recited in any one of claims 1-4 wherein the rate of hydrolysis of coconut oil is 90.0-95.0%.
  6. 6. The method for separating lauric acid from coconut oil according to claim 5, wherein the coconut oil is hydrolyzed by lipase to obtain free fatty acid, and the method comprises the following steps: 1) Hydrolysis, namely uniformly mixing coconut oil, water and lipase, and dynamically hydrolyzing for 8-12 hours at 55-65 ℃ and 160-200 r/min; preferably, the hydrolysis is carried out by using coconut oil, water and aqueous lipase solution, wherein the mass ratio of the coconut oil to the water to the aqueous lipase solution is (1-1.5): 1 (0.003-0.009), and the mass concentration of the lipase in the aqueous lipase solution is 2-5%; 2) Enzyme deactivation; 3) Centrifuging and collecting the upper layer to obtain free fatty acid of coconut oil.
  7. 7. The method for separating lauric acid from coconut oil according to claim 6, In the step 2), the enzyme deactivation method is water-proof boiling for 10-20min; and/or, in the step 3), the centrifugation condition is 5000-10000r/min and 10-20min.
  8. 8. The method of separating lauric acid from coconut oil as recited in any one of claims 1-7 wherein the coconut oil is refined coconut oil that has been subjected to degumming, deacidification, decolorization, and deodorization processes.
  9. 9. The method of separating lauric acid from coconut oil as recited in any one of claims 1 to 8 wherein the number of theoretical plates in the rectification column is 80 to 90.
  10. 10. Use of the method of separating lauric acid from coconut oil as claimed in any one of claims 1-9 to reduce the temperature control energy consumption during separation and extraction of lauric acid.

Description

Method for separating lauric acid from coconut oil and application Technical Field The invention relates to the technical field of substance extraction, in particular to a method for separating lauric acid from coconut oil and application thereof. Background The coconut oil is prepared from coconut pulp through squeezing or leaching and the like, retains natural coconut fragrance, has a saturated fatty acid ratio of about 90%, has unique taste, and is widely applied to food processing of ice products, baking, vegetable products, drinks and the like. In addition, about 50% of lauric acid, and nutritional components such as linoleic acid, phenols, and fat-soluble accompaniment are contained in coconut oil, and play an important role in nutrition and health. Lauric acid is the major saturated fatty acid in coconut oil and represents up to about 50% of the total fatty acid content. Lauric acid can play a role of an emulsification and stabilization system as a food additive, and researches report that lauric acid has a certain antibacterial and antiseptic effect. In a word, this natural component has great application value. At present, lauric acid is mainly obtained by enzymolysis of coconut oil or other vegetable oil to obtain mixed fatty acid, and lauric acid in the mixed fatty acid is distilled out by a molecular distillation technology to achieve the separation effect. The enzymolysis technology is a biological processing technology for decomposing complex macromolecular substances into small molecular substances under mild conditions. Molecular distillation belongs to short-path distillation, the purity of a single distillation product is low, multiple steps of molecular distillation are needed to be designed to improve the purity of lauric acid, the whole separation process is long in time consumption, peculiar smell can be brought to a test environment under a high-temperature condition for a long time, and other long-chain fatty acids can be subjected to high-temperature pyrolysis to influence the recycling of resources. Therefore, further studies on the technique of separating and extracting lauric acid are necessary. Disclosure of Invention One of the purposes of the invention is to provide a method for efficiently separating and obtaining a lauric acid product with high purity, wherein the temperature control energy consumption is lower. The invention provides a method for separating lauric acid from coconut oil, which comprises the following steps of hydrolyzing the coconut oil, separating to obtain free fatty acid of the coconut oil, and sequentially carrying out the following operations: (1) Primary micro-rectification: Carrying out primary micro-rectification on the coconut oil free fatty acid; The primary micro-rectification is carried out under the conditions that the vacuum degree is 14-17mbar, the temperature rising rate is 5-10 ℃ per 10min, the temperature at the top of a rectification column reaches 143-156 ℃, and then intermittent reflux-extraction is carried out for 20-60min according to the mode that 0.75ml-1.25ml of rectification component is collected after 0.5ml of reflux is carried out at 143-156 ℃; (2) Crystallizing and centrifuging: Cooling and crystallizing residues in the rectifying column after the step (1), centrifuging, and collecting liquid components; the method for cooling crystallization comprises cooling the residue to 24-26 ℃ under the conditions of stirring rotation speed of 250-350r/min and cooling rate of 1-5 ℃/30min, and then performing heat preservation crystallization; (3) And (3) secondary micro-rectification: carrying out secondary micro-rectification on the liquid component obtained in the step (2); The condition of the secondary micro-rectification is that under the conditions that the vacuum degree is 2-5mbar and the temperature rising rate is 1-5 ℃ per 10min, the temperature at the top of the rectifying column reaches 148-183 ℃, and then the intermittent reflux-extraction is carried out for 20-60min according to the mode that 0.75ml-1.25ml of rectifying component is collected after 0.5ml of reflux is carried out at 148-183 ℃. The invention provides a method for separating lauric acid from coconut oil, which sequentially carries out specific primary micro-rectification, crystallization, centrifugation and secondary micro-rectification operations on hydrolyzed coconut oil (triglyceride in the coconut oil is changed into free fatty acid) firstly, effectively removes fatty acid components with carbon chain length smaller than 12 through primary micro-rectification, then preliminarily removes high-melting-point long-chain fatty acid components (with carbon number of 14-24) through normal-temperature crystallization and centrifugation (coarse separation of impurities is realized according to melting point difference), and finally obtains high-purity and high-yield lauric acid through secondary micro-rectification. Specifically, the method of the invention can reali