JPS5837837B2 - Method for purifying sugar fatty acid esters - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for purifying sugar fatty acid esters.

More specifically, the present invention relates to a method for removing and purifying fatty acid glycerides from a mixture containing at least sugar fatty acid esters and fatty acid glycerides.

Sugar fatty acid esters have high biodegradability and safety, so they have recently been used as surfactants to fundamentally solve environmental pollution and toxicity problems for living organisms, and have been used as additives in foods, cosmetics, pharmaceuticals, resins, etc. It is an extremely useful compound that is being developed for a wide range of uses, including detergents, laundry detergents, kitchen detergents, and shampoos.

Various methods are known for producing sugar fatty acid esters, but among them, the method using alcoholysis between sugar and fatty acid lower alkyl ester and the method using alcoholysis between sugar and fat or oil, that is, fatty acid triglyceride, are excellent. There is.

In particular, the latter method is an extremely advantageous method for producing sugar fatty acid esters, since comparatively inexpensive animal and vegetable fats and oils such as beef tallow, palm oil, and coconut oil can be used as they are as raw material fats and oils.

The reaction product obtained by this method contains, in addition to sugar fatty acid esters, fatty acid glycerides (usually a mixture of unreacted fatty acid triglycerides, fatty acid diglycerides, and fatty acid monoglycerides), minerals, and unreacted free sugars. Therefore, it is necessary to remove these impurities and purify the sugar fatty acid ester.

Among these impurities, soaps and free sugars can be easily removed without substantial loss of sugar fatty acid esters by converting them into other derivatives or by utilizing differences in solubility in solvents. It is possible to remove it completely.

On the other hand, regarding the removal of fatty acid glycerides, conventionally known methods include solid-liquid extraction using organic solvents such as acetic acid esters and gutones. Since the difference in solubility in organic solvents between sugar fatty acid polyesters having ester bonds and fatty acid glycerides is small, there is a major drawback in that attempting to remove fatty acid glycerides more completely will result in the loss of a large amount of sugar fatty acid esters. There is.

As a result of extensive studies to overcome the deficiencies of such conventional methods, the present inventors have determined that fatty acid glycerides can be converted by treating a mixture containing at least sugar fatty acid esters and fatty acid glycerides with a lipolytic enzyme in the presence of water. The present inventors have discovered that fatty acid glycerides can be easily removed by decomposition without substantial loss of sugar fatty acid esters, leading to the completion of the present invention.

Next, the present invention will be explained in detail.

Sugar fatty acid esters used in the method of the present invention include arabinose, xylose, ribose, glucose, mannose, galactose, and fructose.
, maltose, cellobiose, trehalose, kenthiobiose, isomaltose, lactose, sucrose, raffinose, gentianose, maltotriose, stachyose, xylan,
Monosaccharides and disaccharides such as alaban, cellulose, and starch,
All sugar fatty acid esters that are esters of trisaccharides, tetrasaccharides, or polysaccharides and fatty acids having 6 to 24 carbon atoms, and in which one or more ester bonds exist in the same molecule, are included.

In particular, sugar fatty acid ester is one of the sugar fatty acid esters to which the method of the present invention can be most suitably applied.

Further, the fatty acid glyceride is any one of fatty acid triglyceride, fatty acid diglyceride, or fatty acid monoglyceride derived from a fatty acid having 6 to 24 carbon atoms, or
A mixture of two or more types is used.

The mixture to which the method of the present invention is applied is a mixture containing at least the above-mentioned sugar fatty acid ester and fatty acid glyceride, and in addition to these two components, minerals such as sodium soap, potassium soap, amine soap, and calunium soap are used. It is also applicable to mixtures containing saccharides, free fatty acids, free sugars, glycerin, inorganic salts, and the like.

These mixtures can be used as is or with coexisting soaps,
After some or all of free fatty acids, free sugars, etc. are removed in advance, water is added to dissolve or suspend them in water.

The amount of water added is usually such that the concentration of the mixture is 1 to 90% by weight, preferably 5 to 70% by weight, and more preferably 10 to 50% by weight.
It is best to add it so that

If the amount of water added is too large, it is economically disadvantageous because it requires the energy of many dogs to remove the water afterwards, and if the amount of water added is too small, the viscosity of the aqueous solution of the mixture increases, leading to lipid decomposition. Since mixing with the enzyme becomes insufficient, the effects of the present invention cannot be fully exhibited, and both are unfavorable.

Acylglycerol lipase is a typical example of a lipolytic enzyme, and specifically, acylglycerol lipase derived from Rhizopus, acylglycerol lipase derived from Aspergillus, and acylglycerol lipase derived from Mucoa.
Examples include acylglycerol lipase derived from Pseudomonas, acylglycerol lipase derived from Candida, and acylglycerol lipase derived from pancreas.

Furthermore, the lipolytic enzyme does not necessarily have to be purified acylglycerol lipase, and any enzyme that has lipolytic activity and does not decompose sugar fatty acid esters can be used.

These lipolytic enzymes are added to the aqueous solution or aqueous suspension of the mixture containing at least a sugar fatty acid ester and a fatty acid glyceride, either as they are or after being dissolved in water in advance.

pH and temperature are most important when treating with lipolytic enzymes.

The pH depends on the type of lipolytic enzyme used, but is usually 2 to 10, preferably 3 to 9.5, and more preferably 4 to 9.
It is best to adjust it to

Usual acids, alkalis, salts, etc. can be used as pH adjusters.

Further, the temperature is usually maintained at 10 to 70°C, preferably 20 to 60°C, and more preferably 25 to 50°C.

When the pH and temperature are outside the above ranges, the action of lipolytic enzymes is suppressed, and under strongly acidic or alkaline conditions and at high temperatures, the acid bases of the sugar fatty acid esters themselves are inhibited. This is not preferable because the hydrolysis reaction by the catalyst is accelerated.

The amount of lipolytic enzyme used varies depending on the content of fatty acid glyceride contained in the mixture and the potency of the lipolytic enzyme itself, but it is usually 0.0001 to 2.
0% by weight, preferably 0. 0 0 0 5-10% by weight
, more preferably 0.001 to 5% by weight.

If the amount of the lipolytic enzyme used is less than the above-mentioned lower limit, the effect of the present invention cannot be fully exhibited, and if it is used in a large amount, it becomes uneconomical, which is not preferable.

The treatment time with lipolytic enzyme is usually 1 to 100 hours,
The time is preferably 3 to 70 hours, more preferably 5 to 50 hours.

By employing the treatment conditions with the above-mentioned suitable lipolytic enzyme, most or almost all of the fatty acid glycerides contained in the mixture are finally decomposed into free fatty acids and glycerin.

The thus obtained solution treated with the lipolytic enzyme can be easily combined with known purification methods such as filtration, conversion to other derivatives of free fatty acids, solvent extraction, and recrystallization to easily obtain highly pure sugar fatty acid esters. be able to.

As detailed above, according to the method of the present invention, fatty acid glycerides in a mixture containing at least sugar fatty acid esters and fatty acid glycerides can be selectively decomposed into free fatty acids and glycerin, which are extremely easy to separate. , it is possible to substantially prevent the loss of sugar fatty acid ester, which is extremely advantageous industrially.

The method of the present invention will be explained in more detail below using Examples and Comparative Examples.

Example l 20 grams of sugar coconut oil fatty acid ester, 10 grams of trilaurin (glycerine trilaurate) and water 70tiI
After adjusting the pH to 5.5 by adding a dilute acetic acid aqueous solution dropwise to the mixed solution, lipase AP4 [manufactured by Amano Pharmaceutical Co., Ltd. 10.05?] was added. was added and treated for 30 hours with continuous stirring in a constant temperature bath at 35°C.Two parts of the treated solution were carefully collected, and the produced lauric acid was added to an alcoholic standard solution of potassium hydroxide using phenol latarein as an indicator. Quantitative analysis (a separate blank test was conducted) using the neutralization titration method revealed that 97% of the trilaurin initially used was hydrolyzed to lauric acid.

In addition, as a result of quantitatively analyzing a part of the separately collected treatment liquid by gas chromatography, it was confirmed that the sucrose coconut oil fatty acid ester was not decomposed.

Example 2 0.005? of Lipase M-APIO (manufactured by Amano Pharmaceutical Co., Ltd.) was added to a mixture of 72 sucrose hydrogenated beef fatty acid ester, 32 distearin (glycerin distearate) and 901 water, and the same procedure as in Example 1 was carried out. After treatment at 35° C. for 30 hours and analysis, it was found that 98% of distearin was hydrolyzed to stearic acid, and no decomposition of sucrose hydrogenated beef fatty acid ester was observed.

Example 3 Cane sugar monopalmite} 1 0? , sugar dipalmitate 5g, palm oil (saponification value 198 KOH/P) 5
P, a mixture of 52 g of potassium palmitate and 75 g of water (
0.11' of pancreatin (manufactured by Amano Pharmaceutical Co., Ltd.) was added to the solution (pH 9.2) and treated in a constant temperature bath at 30°C for 48 hours with stirring. 72% of the palm oil obtained was hydrolyzed to the corresponding fatty acids, and no decomposition of sucrose monopalmitate and sucrose dipalmitate was observed.

Example 4 Sucrose monolaurate 10.5? , sucrose dilaurate 4.51, monolaurin (glycerol monolaurate)
32. After adjusting the pH to 8 by dropping acetic acid into a mixture of 21 dilaurin (glycerin dilaurate), 15 g potassium laurate, and 65 da water, pancreatin 0.021
' and lipase M-AP10, 0.0051, and
After 24 hours of treatment in a constant temperature bath at 0°C, analysis revealed that 95% of monolaurin and all of dilaurin were hydrolyzed to lauric acid, with no decomposition of sucrose monolaurate and sucrose dilaurate. I couldn't.

Example 5 Crude sucrose fatty acid esters (20% sucrose fatty acid monoester, 9% sucrose fatty acid diester,
Fatty acid monoglyceride 10%, fatty acid diglyceride 10%
%, fatty acid triglyceride 4%, potassium soap 30%
and free sucrose (containing 17%) 351 and water 65'? After adjusting the pH to 7.5 by adding acetic acid dropwise to the mixture, Lipase M-
AP10, 0.02] was added, and the treatment was carried out for 20 hours with stirring in a constant temperature bath at 40°C.

Next, a potassium hydroxide aqueous solution is added to the treatment liquid to convert the fatty acids in the treatment liquid to potassium soap, and then calcium chloride is added to convert the potassium soap to calcium soap. After distilling off a portion of the water under reduced pressure to make a wet cookie, inpropanol 100
Extraction was performed using ml.

The same extraction operation was repeated once more, and the obtained isopropanol extract was concentrated under reduced pressure to obtain 10.4P of solid material.

As a result of compositional analysis using gas chromatography and liquid chromatography, it was found that sucrose fatty acid monoester 6
6%, sucrose fatty acid diester 29%, free sucrose 1%
, fatty acid monoglyceride 3% and fatty acid diglyceride 1
%, and the purity of the sucrose fatty acid ester (monoester + diester) was 95%.

Furthermore, when the purification yields of sucrose fatty acid monoester and sucrose fatty acid diester are calculated from these results, they are each 98.
1% and 95.7%.

Example 6 Crude sucrose fatty acid ester obtained by alcohol rinsing with sucrose and coconut oil using potassium carbonate and potassium hydroxide as catalysts (25% sucrose fatty acid monoester, 10% sucrose fatty acid diester, 12 fatty acid monoglycerides)
%, fatty acid diglyceride 8%, fatty acid triglyceride 2
%, potassium soap, free sucrose, glycerin, etc. 43
%) citric acid 2.41 in a mixture of 401 and water 60P
After adjusting the pH to 6 by adding Lipase P [manufactured by Amano Pharmaceutical Co., Ltd.] o. Osy was added and the mixture was treated for 24 hours with stirring in a constant temperature bath at 40°C.

After the treatment, a part of the treated solution was collected and freeze-dried, and the composition was analyzed using gas chromatography and liquid chromatography. As a result, the content of fatty acid monocryceride was 3%, and the content of fatty acid diglyceride and Fatty acid triglycerides were not detected.

In addition, the content of sucrose fatty acid ester is monoester 2
3.5% and diester 9.4%, and considering the dilution effect caused by adding 2.42% of citric acid during pH adjustment, it was found that the sucrose fatty acid ester was not substantially decomposed.

Comparative Example 1 Calcium chloride was added to a mixture of 35 g of crude sucrose fatty acid ester and 65 g of water, exactly the same as in Example 5, to convert potassium soap into calcium soap, and then most of the water was distilled off under reduced pressure. After removing the residue to form a wet cake, extraction and concentration were performed in the same manner as in Example 5 to obtain a solid.

Next, 100 ml of ethyl acetate was added to this solid to extract fatty acid glycerides.

The same extraction operation was repeated once more, and the obtained ethyl acetate extract was concentrated under reduced pressure to obtain solid substance 9,71.

As a result of compositional analysis, it contains 63% sucrose fatty acid monoester, 23% sucrose fatty acid diester, 1% free sucrose, 10% fatty acid monoglyceride, and 3% fatty acid diglyceride, and contains sucrose fatty acid ester (monoester +
(diester) purity was 86%.

Furthermore, when the purification yields of sucrose fatty acid monoester and sucrose fatty acid diester were calculated from these results, they were each 87.
3% and 70.8%.

Example 7 Roughinose monostearate 51, maltotriose monostearate 51, trilaurin 101 and water so
Lipase M-AP10, 0.05P was added to the mixed solution of y, and the treatment was performed for 30 hours while stirring in a constant temperature bath at 40°C. As a result, 95% of the trilaurin that was initially present was hydrolyzed. There was found.

Note that substantially no decomposition of raffinose monostearate 14 and maltotriose monostearate was observed.

Claims (1)

[Claims] 1. A method for purifying a sugar fatty acid ester from a mixture containing at least a sugar fatty acid ester and a fatty acid glyceride, which comprises treating the mixture with a lipolytic enzyme in the presence of water to decompose the fatty acid glyceride. Purification method.