JP2001139679A - Polyglycerin faty acid monoester and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyglycerin fatty acid monoester which has a high content ratio of the polyglycerin fatty acid monoester and a high degree of polymerization of the polyglycerin moiety and excels in hue and has a high foaming power, and a method of manufacturing the same. SOLUTION: The method of manufacturing the polyglycerin fatty acid monoester comprises slowly adding a fatty acid, glycidol and/or a catalyst at a reaction temperature of 100-180 deg.C to effect reaction in such a manner that the ratio of the glycerin fatty acid diester to the glycerin fatty acid monoester present in the reaction product comes to a peak area ratio, by the HPLC analysis under specific conditions, of <=1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyglycerin monofatty acid ester and a method for producing the same. More specifically, the present invention relates to a polyglycerin monofatty acid ester having a high content of a polyglycerin monofatty acid ester, a high degree of polymerization of a polyglycerin portion, an excellent bubble force, a low coloration, and a low gel-like substance, and a method for producing the same. In the present specification, when indicating the entire product or product, it is referred to as `` polyglycerin monofatty acid ester '', and when representing the polyglycerin monofatty acid ester itself, which is a compound contained as a main component therein, It is referred to as "polyglycerin monofatty acid ester" or "monofatty acid ester" for short. The polyglycerol monofatty acid ester obtained according to the present invention is useful as an emulsifier or base in the fields of food, cosmetics, medicine and the like.

[0002]

2. Description of the Related Art In recent years, polyglycerin fatty acid esters have been approved as food additives, and their use has been gradually increasing. In general, this ester is obtained by combining esters of polyglycerin having different degrees of polymerization with fatty acids having different chain lengths as raw materials to obtain an ester having a wide range of HLB values, and showing high stability in an acidic region. In the food field, it is widely used as an emulsifier and a viscosity modifier. The method for producing polyglycerin fatty acid ester includes (1) an esterification reaction between polyglycerin and a fatty acid,
(2) transesterification reaction between polyglycerin and fatty acid ester, (3) transesterification reaction between polyglycerin and fat, (4) addition polymerization reaction between glycidol and fatty acid monoglyceride, (5) addition polymerization between glycidol and fatty acid There are reactions. Among them, the methods (2) and (3) have many restrictions in terms of reactivity, quality and purity of the produced polyglycerol fatty acid ester, and the like.

The method (1) is based on JAOCS (Journal of A).
American 0il Chemists' Society) Vol. 58, No. 878
(1981) discloses a method for obtaining a polyglycerin fatty acid ester by subjecting polyglycerin and a fatty acid to an esterification reaction in the presence of an alkali catalyst. A similar method is disclosed in Japanese Patent Application Laid-Open No. 6-41007. In this method, generally, a raw material polyglycerol having an average of 4 to 10 reactive hydroxyl groups is used. Even if an attempt is made to produce a mono-substituted fatty acid ester, the reactive activity is based on the equivalent of the fatty acid used. In the polyglycerol monofatty acid ester having a large ratio of hydroxyl groups, not only the intended monofatty acid ester but also unreacted polyglycerol, diester, triester, tetraester, and other polysubstituted esterified compounds remain. (N. Garti, et al, JA
OCS (Journal of American 0il Chemists' Societ
y) Vol. 59, pp. 317-319 (1982)).
The method (4) is described in US Pat. No. 4,515,775. In this method, the purity of the reaction product is greatly affected by the degree of purification of the raw material fatty acid monoglyceride. In particular, when fatty acid monoglyceride obtained by the reaction between glycerin and a fatty acid was used as a raw material, a glycerin component remained in the raw material, as in (1), and the glycerol was obtained by an addition polymerization reaction of glycidol. The monofatty acid ester content in the polyglycerin monofatty acid ester is about 40%, and it is recognized that the remaining about 60% is unreacted glycerin and di- or higher-substituted ester (Shigeru Tsuda, Monoglyceride, P67
(1985), Maki Shoten). The method (5) is described in
No. 1-65705 describes a monofatty acid ester of glycerin. According to this disclosed technique, a high concentration percentage of carboxylic acid-1-monoglyceride (the following chemical formula [ 1], the value of n is 1 on average.), The degree of polymerization of glycerin is 1 on average, and no mention is made of polyglycerin monofatty acid esters. Has not been considered.

[0004] As a technique using the addition polymerization reaction of glycidol, there is known an addition polymerization reaction of glycerin and glycidol in producing polyglycerin used in the methods (1) to (3) (Japanese Patent Publication No. 1-55254). JP-B-4-11532, JP-B5-11291) or production of polyglycerin which is subjected to an addition polymerization reaction of a fatty acid and glycidol followed by a hydrolysis reaction (Japanese Patent Publication 4-6962).
No. 1), production of polyglycerin monoalkyl ether and polyglycerin monoalkylthioether (USP
3,821,372, USP 3,966,398, US
P4, 087, 466).

However, in the production of polyglycerin via a hydrolysis reaction after the addition polymerization reaction of a fatty acid and glycidol disclosed in Japanese Patent Publication No. 4-69621, the fatty acid used is a lower (2 to 6 carbon atoms) fatty acid, and The purpose is to produce polyglycerin, and there is no mention of polyglycerin fatty acid esters. in this way,
Conventionally used polyglycerol monofatty acid esters contain a large amount of unsubstituted polyglycerin and esterified products having two or more substitutions, and when these are applied to surfactants and emulsion stabilizers in the food field, the surface tension is reduced. It is feared that the water content, the dispersing power, the foaming power, and the emulsification stability are lowered.

On the other hand, as a method for removing unsubstituted polyglycerin, at least one selected from water-soluble organic solvents and water and at least one selected from non-water-soluble organic solvents are used in combination. (Japanese Unexamined Patent Publication (Kokai) No. 63-23837), a method of contacting and adsorbing a solution of an esterification reaction product with an alkylsilylated silica gel to remove unreacted polyglycerin. (JP-A-3-81252), a method of extracting and removing unreacted polyglycerin using a water-soluble organic solvent and an aqueous solution containing water or a salting-out agent (JP-A-6-41)
007 publication) has been proposed.

However, in the method described in Japanese Patent Application Laid-Open No. 63-23837, aromatic hydrocarbons such as benzene and toluene described as water-insoluble organic solvents are questioned about their safety, There are problems with use. Further, in this method, the reaction molar ratio of the fatty acid to polyglycerin is limited to 1 or less, and the effectiveness in the case of a molar ratio exceeding 1 is not described. Even when the reaction molar ratio is 1 or less, toluene /
In the case of a methanol system, a considerable amount of high HLB polyglycerin fatty acid ester is observed to be transferred to the aqueous methanol phase, and in the case of the toluene / methanol system, separation of unreacted polyglycerin is extremely insufficient. There are a number of issues with industrial implementation,
The method of separating with an alkylsilylated silica gel described in JP-A-3-81252 has a high operating cost,
There is also a disadvantage that the operation is complicated. Further, these prior arts have the disadvantage that unreacted polyglycerin can be removed, including the method described in JP-A-6-41007, but it is impossible to remove di- or more-substituted esterified products.

Therefore, when applied to surfactants and emulsion stabilizers in the field of foods, the surface tension and the dispersing power can be improved.
There has been a demand for a polyglycerol monofatty acid ester having a high monofatty acid ester content, which is expected to improve foaming power and emulsion stability, and a method for producing the same.

However, in the prior art, when the reaction is carried out in the absence of a catalyst, the color of the product deteriorates, the amount of unreacted glycidol is large, the bubble power is low, or the product contains a gel-like material. There was a problem that occurs.

In this specification, an international unit system is used as a unit in accordance with the enforcement of the new measurement law. Therefore, "weight" conventionally used in the meaning of mass is described as "mass". In accordance with this, “% by weight”, “parts by weight” and the like are described as “% by weight”, “parts by weight” and the like.

[0011]

An object of the present invention is to provide a polyglycerol monofatty acid ester having a high content of a polyglycerol monofatty acid ester, a high degree of polymerization of a polyglycerol moiety, an excellent hue, and a high foaming power. It is an object of the present invention to provide a manufacturing method thereof.

[0012]

Means for Solving the Problems The present inventors have found that when a fatty acid is reacted with glycidol to produce a polyglycerin monofatty acid ester, the glycerin monofatty acid ester contained in the polyglycerin monofatty acid ester obtained by the reaction is produced. Glycidol is gradually added under specific reaction conditions so that the ratio of glycerol / glycerin difatty acid ester becomes 1 or more in terms of the peak area ratio by HPLC analysis under specific conditions. The inventors have found that a glycerin monofatty acid ester can be obtained, and for that purpose, have found various reaction methods, and have completed the present invention.

That is, a first aspect of the present invention is a polyglycerol monofatty acid ester in which the ratio of glycerin difatty acid ester / glycerin monofatty acid ester is 1 or less as a peak area ratio by HPLC analysis under specific conditions. A glycerin monofatty acid ester is provided. In the second aspect of the present invention, the concentration of the polyglycerin monofatty acid ester contained in the polyglycerin monofatty acid ester is as follows:
The peak area ratio by HPLC analysis under specific conditions was 7
A polyglycerin monofatty acid ester according to the first aspect of the present invention, which is 0% or more. A third aspect of the present invention is the polyglycerin according to the first or second aspect of the present invention, wherein the alkyl group of the fatty acid is a saturated alkyl group having 6 to 21 carbon atoms, an unsaturated alkyl group, or an alkyl group substituted with a hydroxyl group. Provide a mono fatty acid ester. A fourth aspect of the present invention provides the polyglycerol monofatty acid ester according to the third aspect, wherein the fatty acid is lauric acid or stearic acid.
A fifth aspect of the present invention is that the polyglycerin portion of the polyglycerol monofatty acid ester has an average degree of polymerization of glycerin units of 2
A polyglycerin monofatty acid ester according to any one of the first to fourth aspects of the present invention, which is characterized by the above. A sixth aspect of the present invention provides a method for producing a polyglycerin monofatty acid ester by reacting a fatty acid with glycidol in the presence or absence of a catalyst, wherein the glycerin difatty acid ester / glycerin monofatty acid contained in the reaction product is provided. A method for producing a polyglycerol monofatty acid ester, wherein a fatty acid, glycidol and / or a catalyst are gradually added and reacted so that an ester ratio is 1 or less in a peak area ratio by HPLC analysis under specific conditions. I will provide a. The seventh condition of the present invention is that a condition in which glycidol is gradually added and reacted is such that a reaction temperature range is 100 to 100.
180 ° C., the total addition time of gradually added glycidol is 0.5 to 2 hours when the reaction temperature is 160 ° C., and when the reaction temperature is lower, the reaction temperature is 1 hour.
Increase the addition time by 1.5 to 2.5 times per 0 ° C decrease,
When the reaction temperature is higher than that, the addition time is shortened to 2/3 to 2/5 times per 10 ° C. increase of the reaction temperature, the polyglycerin monofatty acid ester according to the sixth aspect of the present invention, A manufacturing method is provided. Eighth of the present invention is
In the method of producing a polyglycerol monofatty acid ester by reacting a fatty acid and glycidol in the presence or absence of a catalyst, the fatty acid alone, or both the fatty acid and the catalyst, while being charged separately to the reactor, Provided is a method for producing a polyglycerol monofatty acid ester, characterized by gradually adding glycidol to the inside and reacting it. A ninth aspect of the present invention provides a method for producing a polyglycerol monofatty acid ester, comprising continuously charging a fatty acid and glycidol or a fatty acid, a catalyst and glycidol to a reactor. In a tenth aspect of the present invention, the alkyl group of the fatty acid is a saturated alkyl group having 6 to 21 carbon atoms, an unsaturated alkyl group, or an alkyl group substituted with a hydroxyl group. And a method for producing a polyglycerin monofatty acid ester. An eleventh aspect of the present invention is the polyglycerol monofatty acid according to any one of the sixth to tenth aspects of the present invention, wherein the polyglycerin portion of the polyglycerol monofatty acid ester has an average degree of polymerization of glycerin units of 2 or more. Provided is a method for producing an ester. A twelfth aspect of the present invention is the sixth to the first aspects of the present invention, wherein the concentration of the polyglycerol monofatty acid ester contained in the polyglycerol monofatty acid ester is 70% or more as a peak area ratio by HPLC analysis under specific conditions.
2. A method for producing the polyglycerol monofatty acid ester according to any one of the above items.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The fatty acid used in the addition polymerization reaction with glycidol is a fatty acid having 6 to 21 carbon atoms in the alkyl group,
Particularly preferred are fatty acids having 7 to 21 carbon atoms in the alkyl group. The fatty acid may be a saturated fatty acid or an unsaturated fatty acid, a linear fatty acid, a fatty acid having a side chain, or a substituted fatty acid having a carbon chain substituted by a hydroxyl group. These fatty acids include, for example, caproic acid, caprylic acid, 2-ethylhexanoic acid, capric acid, lauric acid, isotridecanoic acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, behen Acids, erucic acid, ricinoleic acid, hydroxystearic acid and the like. Of these, lauric acid or stearic acid is particularly preferred. These fatty acids can be used alone,
Two or more kinds may be arbitrarily mixed and used in the reaction.

The reaction between the fatty acid and glycidol is carried out in the presence of a catalyst. However, the reaction can be carried out without a catalyst at the beginning of the reaction. Specifically, a part or all of the fatty acid is placed in a reaction vessel, and glycidol is gradually added to the reaction vessel. The reaction is performed intermittently or continuously according to the method described above, etc.) or a part or all of glycidol is placed in a reaction vessel, and the reaction is performed while gradually adding a fatty acid thereto.

Compared with the case where glycidol is dropped after the fatty acid is charged into the reactor at one time, the glycidol is gradually added while the fatty acid is dividedly charged over the reaction time, or the fatty acid is gradually added to glycidol. When added, the molar ratio of fatty acid / glycidol in the initial stage of the reaction decreases, so that the production ratio of glycerin difatty acid ester can be reduced. The ratio of the divisional charging is not particularly limited, and may be two or more, and the divisional charging may be continuously performed (also referred to as continuous charging, including intermittent charging and pulsating charging). The division may be an equal division or an unequal division. In the case of continuous charging, the fatty acid, glycidol and / or catalyst may be fed separately, or two or more kinds may be mixed and fed. In the continuous charging, the molar ratio of fatty acid / glycidol / catalyst is kept relatively constant, so that the production ratio of glycerin difatty acid ester can be particularly reduced. It is also possible to reduce the generation of a state.

The reaction operation can be carried out batchwise, semi-batchwise or continuously. In the case of batch or half batch, the reaction apparatus can be carried out using one reaction tank or a multi-stage reaction tank. When the reaction is carried out continuously, the reaction can be carried out in a reaction vessel or in a tubular reactor. Moreover, it can also be performed by combining a tubular reactor and a reaction tank.

A low-boiling compound or an inert solvent which does not react with glycidol may be added to the reaction system in order to prevent an increase in the reaction temperature. The reaction is desirably performed in a nitrogen gas atmosphere, and the pressure may be reduced or increased as necessary.

Generally, the reaction temperature for mainly producing a polyglycerol monofatty acid ester from a fatty acid and glycidol is 50 to 180 ° C, preferably 70 to 160 ° C.
° C, more preferably 100 to 150 ° C, particularly preferably 120 to 140 ° C. If the temperature is lower than 50 ° C., the reaction rate is too slow. If the temperature exceeds 180 ° C., the coloring becomes intense. The reaction time is determined in consideration of the reaction temperature, quality and productivity. The conditions for reacting by gradually adding glycidol are as follows:
180 ° C., the total addition time of gradually added glycidol is 0.5 to 2 hours when the reaction temperature is 160 ° C., and when the reaction temperature is lower, the reaction temperature is 1 hour.
If the reaction temperature is higher by 1.5 to 2.5 times the reaction time per 0 ° C. decrease, and the addition time is shortened by 2/3 to 2/5 times per 10 ° C. increase of the reaction temperature. Let react. The relationship between the temperature and the total addition time is, for example, 150
At 1 to 4 hours, preferably 1.5 to 3 hours,
It is 2 to 8 hours at 140 ° C, preferably 3 to 6 hours, 3 to 16 hours at 130 ° C, preferably 4 to 12 hours, and 4 to 18 hours at 125 ° C, preferably 5 to 5 hours.
It is 14 hours, and at 120 ° C., 5 to 20 hours, preferably 6 to 15 hours.

The method of the present invention for producing a polyglycerol monofatty acid ester by reacting a fatty acid with glycidol is carried out in the presence or absence of a catalyst. When a catalyst is used, an acid catalyst is used as the catalyst, and examples of the acid catalyst include Lewis acids, Bronsted acids, and heteropoly acids. Preferably, it is a phosphoric acid acidic catalyst. The phosphoric acid-based catalyst referred to here is phosphoric acids or esters of phosphoric acid, and specifically, phosphoric acid,
Phosphoric anhydride, polyphosphoric acid, orthophosphoric acid, metaphosphoric acid,
Phosphoric acids such as pyrophosphoric acid, triphosphoric acid, and tetraphosphoric acid, or acid phosphates such as methyl acid phosphate, ethyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, and 2-ethylhexyl acid phosphate can be used. . In addition, as these acidic phosphates, any of a monoester body, a diester body, and a mixture thereof can be used. Among the above, it is preferable to use phosphoric acid and acidic phosphoric acid esters. The catalyst may be used anhydrous or in an aqueous solution.

The above catalysts may be used singly or as a mixture of two or more. The amount of the catalyst added is 10% by mass or less based on the fatty acid, preferably 5% by mass.
% By mass or less. If it exceeds 10% by mass, the effect of addition cannot be expected to be improved, and depending on the catalyst used, a large amount of a glycidol addition polymer in which the catalyst serves as an initiator is generated, which is not preferable.

The catalyst may be added to the reaction system from the beginning or may be added after a part of glycidol is added. When the glycidol is added after a part of glycidol is added, preferably, glycidol in an amount equal to or more than an equimolar amount to the fatty acid is added, more preferably at least 2 times the molar amount of the fatty acid, particularly preferably to the fatty acid. This is done after at least 3 moles of glycidol have been added. The addition of the catalyst to the reaction system may be performed all at once or separately. If the catalyst is present prior to the addition of glycidol, a gel will be formed and easily incorporated into the product, or a separation operation will be required to remove it. Here, the gel-like material is considered to be a polysubstituted ester of polyglycerin (having two or more ester groups added) or the like. Of course, the end of the addition of the catalyst to the reaction system is before the total amount of glycidol is added, preferably at the time when 80% of glycidol has not been added, more preferably at the time when 60% of glycidol has not been added. It is. When the catalyst is added to the reaction system after the entire amount of glycidol has been added, the color of the reaction product becomes poor and the residual amount of glycidol tends to increase.

The reaction conditions include the molecular weight of the polyglycerin monofatty acid ester, the content of the polyglycerin monofatty acid ester in the product, the ratio of glycerin monofatty acid ester / glycerin difatty acid ester in the product, and the glycerin difatty acid ester. The content is determined in consideration of the content, the content of the gel, the hue, the generation of the gel, economy, safety, and the like. When the fatty acid to be used is determined to be of a specific type, for example, in order to produce gas bubbles having a predetermined value or more, the ratio of glycerin difatty acid ester / glycerin monofatty acid ester in the product and glycerin It is necessary to consider the content of the difatty acid ester. The ratio of glycerin difatty acid ester / glycerin monofatty acid ester in the product was determined by HPLC under specific conditions described below.
The peak area ratio by analysis is 1 or less, preferably 0.
8 or less, more preferably 0.6 or less. If the ratio of glycerin difatty acid ester / glycerin monofatty acid ester is larger than 1, predetermined physical properties (for example, bubble force) cannot be obtained.

Glycidol is addition-polymerized to the fatty acid by the above reaction, and the following formula [1] RCO- [OCH ₂ CH (OH) CH ₂ ] n-OH [1] (where R is preferably 6 carbon atoms) Represents an alkyl group substituted with an alkyl group, an alkenyl group or a hydroxyl group of from 21 to 21, and n is a numerical value in terms of an average degree of polymerization (number of moles added) of more than 1. For convenience, the formula [1] is represented by 1 of glycerin.
Although an expression in which the ester and / or ether bond is bonded by a secondary alcohol is included in the expression in which the bond is formed only with a secondary alcohol. ) Is produced as a main component. N of the monofatty acid ester is the average degree of polymerization of glycidol (the number of moles added), which is substantially the same as the molar ratio of the fatty acid to be reacted and glycidol, and can be easily changed. n exceeds 1, preferably 2 or more, and more preferably 4 to 10. There is no particular upper limit, but it may be up to about 1,000.

The product is a polyglycerol monofatty acid ester containing a monofatty acid ester as a main component. The term "mainly composed of a monofatty acid ester" means that the product contains 70% or more, preferably 80% or more of a polyglycerin monofatty acid ester. Other components include glycerin monofatty acid ester, polyglycerin difatty acid ester, glycerin difatty acid ester, glycerin, polyglycerin, and unreacted raw material generated by using water in the raw material as an initiator. The polyglycerol monofatty acid ester obtained by the above method is HPLC (High Performance
The content, expressed as the peak area ratio of the monofatty acid ester represented by the general formula [1], which is eluted by a liquid chromatogaraphy analysis method and detected using an ultraviolet absorption detector or the like, is 70% or more. Here, the HPLC analysis method refers to a reversed-phase partitioning type using silica gel having a functional group of octadecylsilyl group, octylsilyl group, butylsilyl group, trimethylsilyl group, or phenylsilyl group as a filler, and cyanopropyl as a functional group. There are a normal phase distribution type using a silica gel having a group and an aminopropyl group as a carrier, an ion exchange type having a quaternary ammonium group and a phenylsulfonic acid group as functional groups, and an adsorption type of porous silica gel. Among these, a reversed-phase partitioning type using silica gel to which an octadecylsilyl (ODS) group is bonded as a carrier is preferably used. Specifically, packing material: Wakosil IIC18HG, column: 4.6 m
mφ × 250 mm. As the detector, an ultraviolet absorption detector, a refractive index detector and the like can be used, but an ultraviolet absorption detector is preferable. The wavelength of the ultraviolet absorption detector is, for example, 2
10 nm. The eluent and flow rate depend on the object. For example, when measuring the content of glycerin dilaurate in polyglycerol monolaurate, the eluent is methanol and the flow rate is 0.20 ml /
Minutes. When measuring glycerin monolaurate, the eluent is methanol / water = 80/20 (volume ratio) and the flow rate is 0.50 ml / min. The sample concentration was 10 or 5% by mass, and the solvent used was the above eluent. The sample injection volume is 5 to 20 μl. Column oven temperature is 40 ° C. Under the above HPLC analysis conditions,
For example, taking the production of polyglycerol laurate as an example, the peak of glycerin monolaurate appears at an elution time of about 18 minutes, and the peak of glycerin dilaurate appears at an elution time of about 34 minutes. Initially, it can be accurately separated and quantified from other peaks. The obtained HPLC analysis result is indicated by the area ratio of each peak. In the present invention, it is important that the ratio of glycerin difatty acid ester / glycerin monofatty acid ester contained in the polyglycerin monofatty acid ester be 1 or less as a peak area ratio by HPLC analysis under specific conditions. When the glycerin difatty acid ester / glycerin monofatty acid ester ratio in the polyglycerin monofatty acid ester is 1 or less, specifically under the above-mentioned analysis conditions,
It is the ratio of the peak area attributed to glycerin difatty acid ester to the peak area attributed to glycerin monofatty acid ester. Similarly, when the peak area ratio of the monofatty acid ester is 70% or more, the peak area ratio attributed to the monofatty acid ester is a reaction product (since it is a reaction product, the solvent, catalyst, unreacted raw material, water, etc. (Not included) means 70% or more of the total peak area.

The polyglycerol monofatty acid ester obtained as described above may be further purified, if necessary, through various purification steps, and then used, for example, as a food additive. Specific purification methods include (a) a deodorizing method in which saturated heated steam is blown under reduced pressure to deodorize steam, and (b) a decolorizing method such as bleaching with sodium hypophosphite or hydrogen peroxide.

As described above, in the present invention, a polyglycerol monofatty acid ester having high purity, in particular, a content of the monofatty acid ester represented by the above-mentioned peak area ratio of 70% is obtained by an addition polymerization reaction of glycidol and a fatty acid. The above polyglycerin monofatty acid ester is obtained.
Since such a polyglycerin monofatty acid ester is used as a food additive such as a surfactant or an emulsion stabilizer, it can improve surface tension, dispersing power, foaming power, and emulsion stability. effective.

Accordingly, the polyglycerin monofatty acid ester obtained in the present invention is used for various applications in which polyglycerin monofatty acid ester and the like are conventionally used, and can sufficiently exhibit its intended function. .

[0029]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. Note that, throughout the examples and comparative examples, HPLC analysis conditions are as described above.

(Measurement of Bubble Force) The height of bubbles was measured according to JIS K3362. The unit is mm.

Example 1 Charge of lauric acid and a catalyst was divided into four parts. In a reactor equipped with a nitrogen inlet pipe, a stirrer, a cooling pipe, a temperature controller and a dropping cylinder, lauric acid 1.
0 mol (200 g), 0.25 mol (50 g)
g) and heated to 150 ° C. Then, while maintaining the reaction temperature at 150 ° C., glycidol was dropped, and 2.0 mol of glycidol (molecular weight: 74.1) (20% of the total amount) was added.
%) (At this point, the charging ratio reaches the lauric acid / glycidol = 1/8 molar ratio), 0.26 g of phosphoric acid (42.5% aqueous solution) (25% of the total amount) is added. For 0.5 hours. Next, lauric acid 0.2
5 mol (50 g) was added, glycidol was added dropwise, and when 2.0 mol of glycidol was added, 0.26 g of an aqueous phosphoric acid solution was added and reacted for 0.5 hour. Further, the same operation was repeated twice, and the remaining amount of lauric acid and the entire amount of glycidol were dropped 80% of the whole amount, and the remaining amount of the phosphoric acid aqueous solution was added and allowed to react for 0.5 hour, and then the remaining glycidol was dropped. Glycidol 10.0m in total
ol (741 g) was added dropwise over 5 hours. After completion of the dropping, the aging reaction was continued at the same temperature, and the oxirane oxygen concentration in the system became 0.12% after 12 hours and 0.08% after 15 hours. Since the oxirane oxygen concentration became 0.1% or less, the mixture was cooled and the reaction product was taken out to obtain 941 g of a product mainly composed of a polyglycerin monolaurate having a glycidol polymerization degree of about 10. The content of the polyglycerin monolaurate in the reaction product was 76 area%, the ratio of laurate / glycerol monolaurate was 0.55, and the bubble power was 225 mm. The color of the product was APHA30, and no gel was found.

(Example 2) 10 mmol of lauric acid was added to the bottom of a tubular reactor filled with a static mixer.
/ Glycidol / 100 mmol / phosphoric acid (42.5% aqueous solution) at a rate of 7.6 mg / min.
The reaction was carried out at 10 ° C. for a residence time of 10 hours, the reaction mass was withdrawn from the top of the tower and supplied to a storage tank equipped with a stirrer.
After aging for a while, supply it to the ion exchange resin tower to separate the acid content, supply it to the purification tower and blow the saturated heating steam under reduced pressure to treat the unreacted glycidol to remove the low boiling point and water. Thus, a product containing polyglycerin monolaurate as a main component was obtained. The content of the polyglycerin monolaurate in the obtained product was 90 area%, the ratio of lauric diester / glycerin monolaurate was 0.48, and the bubble power was 250 mm. The hue of the product is AP
No formation of HA20 or gel was observed.

(Comparative Example 1) 1.0 mol (200 g) of lauric acid and phosphoric acid (42.
1.04 g (5% aqueous solution) was charged and heated to 150 ° C. Next, 10 mol of glycidol was added dropwise over 5 hours while maintaining the reaction temperature at 150 ° C. The charging ratio at the time when 2.0 mol of glycidol (20% of the total amount) was added reached a lauric acid / glycidol = 1/2 molar ratio. After dropping, the ripening reaction was continued at the same temperature, and the oxirane oxygen concentration in the system became 0.1% after 12 hours. The system was cooled, and the reaction product was taken out and polyglycerin monolaurin having a glycidol polymerization degree of about 10 was obtained. 941 g of a product containing an acid ester as a main component was obtained. The content of polyglycerol monolaurate in the reaction product was 7
3 area%, the ratio of lauric acid diester / glycerin monolaurate was 1.54, and the bubble force was 200 mm or less. The color of the product was APHA40.

Example 3 and Comparative Example 2 With respect to the polyglycerol monolaurate obtained by reacting under various conditions, the relationship between the ratio of glycerin dilaurate / glycerin monolaurate and the bubble force was examined. However, the relationship shown in FIG. 1 was obtained. In FIG. 1, the horizontal axis represents the bubble force (unit: mm), and the vertical axis represents the peak area ratio of glycerin dilaurate / glycerin monolaurate in HPLC analysis. The mark ● indicates a comparative example, and the mark × indicates an example.

Example 4 The procedure of Example 1 is repeated, except that stearic acid is used instead of lauric acid, to obtain a product containing polyglycerin monostearate as a main component.

[0036]

According to the present invention, the content of the polyglycerol monofatty acid ester is high, the degree of polymerization of the polyglycerol moiety is high, the hue is excellent, the bubble power is high, and no gel-like substance is produced. A polyglycerol monofatty acid ester with less unreacted glycidol was obtained. When the obtained polyglycerin monofatty acid ester is applied to a surfactant and an emulsion stabilizer in the food field, it has good surface tension, high dispersing power, high foaming power, and good emulsion stability.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between the ratio of glycerin dilaurate / glycerin monolaurate in polyglycerin monolaurate and the foaming power.

Claims (12)

[Claims] 1. A polyglycerol monofatty acid ester in which the ratio of glycerin difatty acid ester / glycerin monofatty acid ester contained in the polyglycerin monofatty acid ester is 1 or less as a peak area ratio by HPLC analysis under specific conditions. 2. The polyglycerin monofatty acid ester according to claim 1, wherein the concentration of the polyglycerin monofatty acid ester contained in the polyglycerin monofatty acid ester is 70% or more in terms of a peak area ratio by HPLC analysis under specific conditions. Fatty acid esters. 3. The polyglycerol monofatty acid ester according to claim 1, wherein the alkyl group of the fatty acid is a saturated alkyl group having 6 to 21 carbon atoms, an unsaturated alkyl group, or an alkyl group substituted with a hydroxyl group. 4. The polyglycerol monofatty acid ester according to claim 3, wherein the fatty acid is lauric acid or stearic acid. 5. The polyglycerol monofatty acid ester according to claim 1, wherein the polyglycerin portion of the polyglycerol monofatty acid ester has an average degree of polymerization of glycerin units of 2 or more. 6. A method for producing a polyglycerin monofatty acid ester by reacting a fatty acid with glycidol in the presence or absence of a catalyst, wherein the glycerin difatty acid ester / glycerin monofatty acid ester contained in the reaction product is produced. A method for producing a polyglycerol monofatty acid ester, wherein a fatty acid, glycidol and / or a catalyst are gradually added and reacted so that the ratio becomes 1 or less as a peak area ratio by HPLC analysis under specific conditions. 7. Conditions for gradually adding glycidol to react are such that the reaction temperature range is 100 to 180 ° C., and when the reaction temperature is 160 ° C., the total time for gradually adding glycidol is 0.5 to 2 hours. When the reaction temperature is lower, the addition time is extended 1.5 to 2.5 times per 10 ° C. decrease in the reaction temperature, and when the reaction temperature is higher, the addition time is 10 to 10 times the reaction temperature. Addition time per 2 ℃ increase
The method for producing a polyglycerol monofatty acid ester according to claim 6, wherein the method is shortened by a factor of ３ to ／. 8. A method for producing a polyglycerol monofatty acid ester by reacting a fatty acid with glycidol in the presence or absence of a catalyst, wherein the fatty acid alone or both the fatty acid and the catalyst are separately charged in a reactor. Glycidol is gradually added thereto while the reaction is being carried out, and a reaction is carried out. 9. A process for producing a polyglycerol monofatty acid ester, comprising continuously charging a fatty acid and glycidol or a fatty acid, a catalyst and glycidol to a reactor. 10. An alkyl group of a fatty acid having 6 to 21 carbon atoms.
The method for producing a polyglycerol monofatty acid ester according to any one of claims 6 to 9, wherein the alkyl group is a saturated alkyl group, an unsaturated alkyl group, or an alkyl group substituted with a hydroxyl group. 11. The polyglycerol portion of the polyglycerol monofatty acid ester has an average degree of polymerization of glycerin units of 2
The method for producing a polyglycerol monofatty acid ester according to any one of claims 6 to 10, which is described above. 12. The method according to claim 6, wherein the concentration of the polyglycerol monofatty acid ester contained in the polyglycerol monofatty acid ester is 70% or more as a peak area ratio by HPLC analysis under specific conditions. A method for producing the polyglycerin monofatty acid ester according to the above.