KR0127510B1 - Separation and purification of monoglyceride in high purity - Google Patents

Abstract

Synthetic method of mono glyceride is disclosed in this invention. Esterification of lipid acid and glycerol by lipase to synthesize high purity of mono glyceride. 10 times by volume of mixture of diethyl ether and nucleic acid whose mixing ratio is 2:1 to 1:2 is admixed, reacted, then mono glyceride is selectively precipitated and separated with high purity.

Description

Separation and Purification Method of High Purity Monoglycerides

The present invention relates to a method for separating and purifying monoglycerides in high purity.

Monoglycerides and their derivatives have been used as surfactants in the food industry, and they have been prepared for transesterification at temperatures of 220 ° C. or higher in the presence of inorganic catalysts from fats and oils and glycerol (Sonnatag N., J. Am. Chem. Soc., 59, 759A, 1982; Laudidsen J., ibid, 53, 400, 1976). However, in such a chemical industrial method, excessive glycerol should be used, and the color of the product becomes darker due to the reaction at high temperature, disgusting odor, and the polymerization reaction of unsaturated fatty acid easily occurs, and the yield is 30 ~. Only 40%.

Therefore, in order to overcome these disadvantages, it was required to carry out the reaction under milder conditions, and thus, methods for separating and purifying monoglycerides using an enzyme called lipase have been actively studied. In the case of using lipase, the enzymatic properties can save energy because it is possible at lower temperature than the chemical industrial method.

Monoglycerides using lipases include a method for binding fatty acids to glycerol, a method for binding fatty acids liberated from triglycerides to glycerol (Holmberg Osterberg J. Am. Oil Chem. Soc., 65, 1544, 1988), and a substrate. Reaction system that is used as a solid substrate with the highest concentration of phosphorus triglycerides (yamane et al., JAOCS, 67, 779, 1990; ibid, 68, 1, 1991; ibid, 68, 6, 1991; EP 445, 692). These various manufacturing methods are to maximize the conversion efficiency by lipase. In fact, the conversion efficiency has increased by 50-85%. However, from a practical practical point of view, the reaction product contains only triglycerides, enzyme proteins, etc. in addition to monoglycerides, free fatty acids, and diglycerides in chemical transesterification and lipase conversion reactions. Recovery is important. Conventionally, molecular weight distillation (molecular distillation) is used, the yield is high, but the work is cumbersome and the device has a complex problem.

Therefore, the present inventors have studied the method to solve the above problems and to selectively recover only monoglycerides from the reaction product. The precipitation was found and the present invention was completed.

Accordingly, it is an object of the present invention to add a mixed solvent of 2 to 1 parts by weight of diethyl ether and 1 to 2 parts by weight of hexane in an esterification reaction of a fatty acid using lipase with glycerol from the reaction mixture A method of separating and purifying monoglycerides by selective precipitation-accumulation is provided.

Hereinafter, the present invention will be described in detail.

The fatty acid used in the separation and purification method of the monoglyceride of the present invention is not particularly limited. In the case of palm stearin, the composition is very high: C12 0.7%, C14 1.5% C16 55.8%, C18 4.8%, C18: 1 29.6%, C18: 2 7.2%, C18: 3 0.1%, C20 0.4%, C22 0.1% Complicated, stearin is not the only ingredient. Therefore, in the present specification, the term free fatty acid is used instead of free stearic acid.

The monoglycerides can be recovered with high purity by selective precipitation of a mixed solvent of diethyl ether and hexane because monoglycerides are less soluble in this mixed solvent than diglycerides and triglycerides. It is a very basic concept to purify a substance using such a difference in solubility in a specific solvent, but a mixed solvent of diethyl ether and hexane to selectively separate monoglycerides from a reaction mixture containing diglycerides and triglycerides together. It is a fact first revealed by the present inventors to use.

In order to determine when it is preferable to add a mixture of diethyl ether and hexane for the selective precipitation of monoglycerides during the reaction, the composition ratio of the reactants during the esterification reaction was investigated. 9.09 g of palm stearin (manufactured by Samlip Oil) heated to 55 ° C was mixed with 2.1 g of glycerol (manufactured by Ilshin Emulsifier) and 9780Unit of lipase PS (manufactured by Amano Co., Ltd.), and cured by stirring at 800 rpm. During the reaction for a total of 72 hours at 38 ℃, 800rpm, the content of monoglycerides, free fatty acids, diglycerides, triglycerides over time was investigated. The results are shown in Table 1.

TABLE 1

Composition ratio of monoglycerides (MG), free stearic acid (FFA), diglycerides (DG), and triglycerides (TG) over time

According to Table 1, the content of monoglyceride was 52.9% at 25 hours, while the conversion efficiency increased only 22.7% even after 47 hours.

Therefore, monoglyceride having a purity of 100% can be obtained by adding a mixed solvent of diethyl ether and hexane to a reaction solution having a monoglyceride content of 50% or more. That is, the monoglyceride of high purity may be prepared by treating the reactant reacted with lipase for about 25 hours with a mixed solvent of diethyl ether and hexane.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the concept of the present invention is not limited to the embodiment.

In the present invention, glyceride analysis was performed according to the following analysis method. Take 150 mg of the sample, dissolve in chloroform, load 1 μl of the sample extracted with chloroform using a crystal rod (Chromarod SIII) of Itaroscan (Iatroscan Model TH-10, manufactured by Itaron, Japan), and add hexane: di. After developing with a solvent of ethyl ether: acetic acid = 55: 15: 0.5, the load was dried and the peak area shown by scanning was used as a quantitative value. As a result, it was possible to quantify monoglycerides, free fatty acids, 1,2-diglycerides, 1,3-diglycerides, and triglycerides.

Example 1

9.09 g of palm stearin (manufactured by Samlip Oil) heated to 55 ° C. was mixed with 2.1 g of lipase PS (manufactured by Ilshin Emulsified) 9780Unit of glycerol (manufactured by Ilshin Chemical Co., Ltd.), stirred at 800 rpm, and solidified. To 3 g of the reaction product obtained by reacting at 38 ° C. and 800 rpm for a total of 25 hours, 50 ml of a mixed solvent of diethyl ether: hexane = 1: 1 were added, and the mixture was left at room temperature for 1 hour and then centrifuged. Looking at the composition ratio of the precipitate, monoglyceride was 93.5%, free stearic acid 0%, diglyceride 4.2% (1,2-DG 4.2%, 1,3-DG 0%), triglyceride 2.3%.

Example 2

50 ml of a mixed solvent of diethyl ether: hexane = 1: 1 was added to the precipitate of Example 1, and the mixture was left at room temperature for 1 hour and then centrifuged. The precipitate was 100% monoglycerides.

Example 3

The same procedure as in Example 1 was carried out except that diethyl ether: hexane = 1: 2 was used. The composition ratio of the precipitate was 90.9% of monoglycerides, 0.9% of free stearic acid, 4.4% of diglycerides (4.4% of 1,2-DG, 0% of 1,3-DG), and 3.8% of triglycerides.

50 ml of a mixed solvent of diethyl ether: hexane = 1: 2 was added to the precipitate obtained above, and the mixture was left at room temperature for 1 hour and then centrifuged. The precipitate was 100% monoglycerides.

Example 4-6

It carried out by the same method as Example 1 except having changed the composition ratio of diethyl ether and hexane into 2: 1, 3: 1, 1: 3 etc. The results were shown in Table 2.

TABLE 2

Changes in Sediment and Secondary Sedimentation with Diethyl Ether and Hexane Compositions

However, when the precipitation was attempted in the third step, all became 100% monoglycerides.

Example 7

A precipitate was obtained in the same manner as in Example 1 except that the amount of the reactant obtained in Example 1 was 5g, 6g, 8g, 10g, and the obtained precipitate was repeated two more times with the same mixed solvent. The results obtained are shown in Table 3.

TABLE 3

Changes in the composition of the precipitate depending on the amount of reactants

As shown in Table 3 above, up to 5 g of the reactant was extracted three times with a solvent to recover only monoglycerides.

Comparative Example 1

50 ml of hexane was added to 3 g of the reaction product obtained in Example 1, and the mixture was left at room temperature for 1 hour and then centrifuged. Looking at the composition of the precipitate, 78.3% monoglycerides, 0% free fatty acids, 17.4% (1,2-DG 10.4%, 1,3-DG 7.0%), triglycerides were 4.3%.

Comparative Example 2

50 ml of diethyl ether was added to 3 g of the reaction product of Example 1, and the mixture was left at room temperature for 1 hour and then centrifuged. The composition ratio of the monoglyceride was 95.2%, free fatty acid 0.4%, diglyceride 3.7% (1,2-DG 1.1%, 1,3-DG 2.6%), triglyceride 0.6%.

However, three precipitation attempts did not yield 100% monoglycerides.

As can be seen from the above examples and comparative examples, when a mixed solvent of diethyl ether: hexane = 2: 1, 1: 1, 1: 2 is added in 10 times the volume of the reactant, glycerol, palm stearin, lipase Pure monoglycerides could be recovered from the reaction.

Claims (3)

A method for separating and purifying high-purity monoglycerides, comprising adding a mixed solvent of diethyl ether and hexane in an ester reaction of glycerol and palm stearin using lipase. The method of claim 1, wherein the mixed solvent of diethyl ether and hexane has a mixing weight ratio of diethyl ether: hexane of 2 to 1: 1 to 2. The method for separating and purifying high-purity monoglycerides according to claim 1 or 2, wherein a mixed solvent of diethyl ether and hexane is added in a volume of 10 times the reactant.