JP2003164754A - Stabilized w/o/w emulsion and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prepare a W/O/W emulsion capable of effectively suppressing the leakage of useful substances contained in an inner aqueous phase. <P>SOLUTION: In the W/O/W emulsion which contains the useful substances in the inner aqueous phase and contains an aqueous emulsifier in an outer aqueous phase and/or the inner aqueous phase, the aqueous emulsifier is an ester of a fatty acid having a carbon number of 18 or higher and a polyglycerin. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a stabilized W / O / W.
The present invention relates to an emulsion and a method for producing the emulsion.

[0002]

W / O / W which is a liquid microcapsule
The emulsion is an emulsion in which W / O droplets are dispersed in an aqueous phase (outer aqueous phase). With a W / O / W emulsion,
By enclosing a useful substance inside the W / O droplet, it can be applied to various uses such as foods, pharmaceuticals, and cosmetics. The W / O / W emulsion can also be used as an intermediate in the manufacturing process.
In order to utilize the merit of the W / O / W emulsion in these applications, it is premised that the leakage of the useful substance inside the W / O droplet is effectively suppressed or the release rate of the useful substance can be controlled. Becomes

However, there is still a problem that useful substances encapsulated in W / O droplets leak to the external water phase in large quantities during the production or storage of the W / O / W emulsion, and as a microcapsule. Product development has not progressed sufficiently. Of course, the function of releasing the useful substance from the microcapsules at an appropriate rate (slow release function) has not been realized.

Several methods have been proposed to solve these problems. For example, a fatty acid having 16 to 22 carbon atoms or a condensed oxyfatty acid containing an HLB of 7 or more hydrophilic emulsifier consisting of an ester of a fatty acid and a polyhydric alcohol in the inner aqueous phase and containing 50% or more of unsaturated fatty acid in the oil phase. A W / O / W emulsion composition containing a lipophilic emulsifier composed of an ester of a polyhydric alcohol having 4 or more carbon atoms and a hydrophilic emulsifier having HLB of 5 or more in the outer aqueous phase (JP-A-200)
1-25360) is known.

For example, a W / O emulsion having a gel phase at normal temperature and a liquid crystal phase at a certain phase transition temperature or higher is used to prepare a W / O emulsion having the liquid crystal composition as an internal water phase. After that, there is a method for producing a W / O / W emulsion in which the liquid crystal is in the inner aqueous phase by cooling to below the transition temperature (JP-A-10-137576).

For example, a gel is formed by once forming a gel from at least one of polyhydric alcohols, sugars and amino acids and an oily surfactant, and then adding an oil phase containing a hydrophilic core substance and an oil component to the gel. A method of microencapsulating a W / O emulsion by an emulsification method is disclosed.

For example, a W / O / W emulsion using a partially or completely crosslinked organoopolysiloxane elastomer having a polyoxyethylene chain and / or a polyoxypolypropylene chain (Japanese Patent Laid-Open No. 2000-342).
21) is disclosed.

[0008]

However, although these techniques can improve the emulsion stability, they effectively prevent the useful substance contained in the W / O droplets from leaking to the external water phase. Further improvement is necessary to suppress this.

According to the research conducted by the present inventor, it has been found that there are three main causes of the leakage problem.

First, there is a problem in the method of preparing a W / O / W emulsion. In conventional emulsification methods such as a homomixer and a high-pressure homogenizer, a strong shearing force is applied.
As a result of mechanical destruction of at least some of the / O droplets,
The internal water phase leaks to the external water phase at a high rate.

Second, there is a problem with the W / O droplet itself. That is, because the W / O droplets are unstable or the conditions such as osmotic pressure are inappropriate, the W / O droplets are destroyed and leaked after the preparation of the W / O / W emulsion.

Third, there is the problem of the oil phase. Stable W / O
Even when droplets are prepared, leakage can be caused by the commonly used oily surfactants in the oil phase serving to carry useful substances.

Therefore, the main object of the present invention is to provide a W / O / W emulsion which can solve these problems and effectively suppress the leakage of useful substances contained in the inner aqueous phase.

[0014]

Means for Solving the Problems As a result of intensive studies in view of the problems of the prior art, the present inventor has found that an emulsion obtained by adopting a specific composition and a specific production method can achieve the above object. Finally, the present invention has been completed.

That is, the present invention provides the following stabilized W / O
/ W emulsion and its manufacturing method.

1. W / O containing a useful substance in the inner water phase and an aqueous emulsifier in the outer water phase and / or the inner water phase
/ W emulsion, wherein the aqueous emulsifier is an ester of a fatty acid having 18 or more carbon atoms and polyglycerin, a W / O / W emulsion.

2. Item 2. The W / O / W emulsion according to Item 1, wherein the oil phase contains a fatty acid having 18 or more carbon atoms.

3. W / O / according to the above 1 or 2, wherein the oil phase contains polyglycerin condensed ricinoleic acid ester.
W emulsion.

4. Item 4. The W / O / W emulsion according to any one of Items 1 to 3, wherein the useful substance is a water-soluble physiologically active substance.

5. Item 5. The W / O / W emulsion according to Item 4, wherein the water-soluble physiologically active substance is anthocyanin.

6. A W / O emulsion in which a first aqueous phase containing a useful substance is dispersed in an oil phase is permeated through a porous membrane to be dispersed in a second aqueous phase, thereby making the first aqueous phase an inner aqueous phase, A method for producing a W / O / W emulsion having a second aqueous phase as an external aqueous phase, which comprises, as an aqueous emulsifier, an ester of a fatty acid having 18 or more carbon atoms and polyglycerin as a first aqueous phase and / or a second aqueous phase. A method for producing a W / O / W emulsion, characterized in that it is contained in an aqueous phase.

7. 7. The method according to item 6, wherein the W / O / W emulsion is further permeated through the porous membrane.

8. W / O containing a useful substance in the inner water phase and an aqueous emulsifier in the outer water phase and / or the inner water phase
In the / W emulsion, the aqueous emulsifier is a W / O / W emulsion characterized by being an ester of a fatty acid having 18 or more carbon atoms and polyglycerin, and the second aqueous emulsifier (however, The method of controlling the release rate of a useful substance into the external aqueous phase by further adding the above-mentioned aqueous emulsifier).

9. Item 9. The method according to Item 8, wherein the second aqueous emulsifier is at least one ester of polyglycerin lauric acid ester, sucrose lauric acid ester, sucrose stearic acid ester and decaglycerin caprylic acid ester. 10. Item 4. The W / O / W emulsion according to any one of Items 1 to 3, wherein the useful substance is polyphenol. 11. In a W / O / W emulsion containing a useful substance in the inner water phase and containing an aqueous emulsifier only in the outer water phase, the aqueous emulsifier is an ester of a fatty acid having 18 or more carbon atoms and polyglycerin. W / O characterized by
/ W emulsion. 12. W / where the first aqueous phase containing useful substances is dispersed in the oil phase
A W / O / W emulsion having the first water phase as the inner water phase and the second water phase as the outer water phase is obtained by permeating the O emulsion through the porous membrane and dispersing it in the second water phase. A method for producing a W / O / W emulsion, which comprises, as an aqueous emulsifier, an ester of a fatty acid having 18 or more carbon atoms and polyglycerin in the second aqueous phase. 13. In a W / O / W emulsion containing a useful substance in the inner water phase and containing an aqueous emulsifier only in the outer water phase, the aqueous emulsifier is an ester of a fatty acid having 18 or more carbon atoms and polyglycerin. W / O characterized by
/ W emulsion is used, and the second aqueous emulsifier (however, the above-mentioned aqueous emulsifier is excluded) is further added to the external water phase to control the release rate of the useful substance into the external water phase.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION 1. Stabilized W / O / W Emulsion The W / O / W emulsion of the present invention is a W / O containing a useful substance in the inner water phase and an aqueous emulsifier in the outer water phase and / or the inner water phase. In the / W emulsion, the aqueous emulsifier is an ester of a fatty acid having 18 or more carbon atoms and polyglycerin.

The present invention is an emulsion having a water phase (inner water phase) / oil phase / water phase (outer water phase) as a basic component, and contains an aqueous emulsifier in the outer water phase and / or the inner water phase. .

Water can be used for the inner water phase and the outer water phase. The oil phase may be appropriately selected from oil phases (oil agents) used in known W / O / W emulsions according to the application. For example, in the case of producing pharmaceuticals, foods, etc., oils that can be used for food, drinking, skin application, etc. are used, for example soybean oil, corn oil, peanut oil, vegetable oil such as cottonseed oil, beef tallow, lard, whale fat, etc. And synthetic oils such as neutral triglycerides. When manufacturing anything other than products such as pharmaceuticals and foods, other fuel oils such as kerosene, light oil, heavy oil, spindle oil, compressor oil, turbine oil, machine oil, engine oil, gear oil, etc., Liquid paraffin, paraffin oil such as petroleum wax, silicone oil, olefin polymer oil, diester oil,
Examples include synthetic oil agents such as polyalkyl glycol oils. These can be used alone or in combination of two or more.

The useful substance is not limited as long as it can be mixed with water in the inner aqueous phase to prepare a W / O / W emulsion, and may be appropriately selected depending on the purpose of use of the emulsion. Further, it does not matter whether it is a natural product or a synthetic product.
Specific applications include chemical products, drugs, pharmaceuticals, agricultural chemicals,
Examples include feed, fertilizer, food and the like.

In the present invention, a water-soluble physiologically active substance can be preferably used. The water-soluble bioactive substance is not limited,
Known ones can also be used. For example, in addition to components extracted or purified from organisms such as animals and plants or minerals or processed products thereof, components obtained by further modifying the components can be used. The extraction method is not limited, and for example, a method of using water, alcohol, propylene glycol, glycerin, liquid carbon dioxide gas or the like as a solvent, bringing the raw material into contact with the solvent, and then removing the solvent can be applied. The purification method is not particularly limited, and examples thereof include adsorption method, filtration method, distillation method and the like.

Specific examples of the water-soluble physiological substance include pigments such as red cabbage pigment, perilla pigment, safflower pigment, xylol, sorbitol, licorice extract, sweeteners such as oligosaccharides, guanylic acid, inosinic acid and aspartic acid. , Seasonings such as arginine, asparagine, taurine, amino acids,
Examples include preservatives such as catechin and ellagic acid. Also,
For example, caffeine, stevia extract, sweet tea extract, extracted tannin, citrus seed extract, mulberry extract, red cabbage extract, perilla extract, purple sweet potato extract, blueberry extract,
Grape seed coat extract and the like can also be used. Further, meat extract, fish shellfish extract, yeast extract, HAP (animal protein hydrolyzate), HVP (vegetable protein hydrolyzate) and the like can be used. Also, polyphenols and the like can be used.

In the present invention, of these, polyphenols (particularly anthocyanins) can be preferably used.
As the anthocyanins, those extracted from red cabbage, perilla, purple sweet potato, blueberries, grape seed coat and the like can be generally used, but synthetic products may also be used.

The aqueous emulsifier may be contained in at least one of the outer water phase and the inner water phase, but in the present invention, it is preferably contained in at least the outer water phase. Further, a mode in which the aqueous emulsifier is contained only in the outer water phase is also preferable.

As the aqueous emulsifier, an ester of a fatty acid having 18 or more carbon atoms and polyglycerin is used (hereinafter also referred to as "the emulsifier of the present invention"). As the above-mentioned fatty acid, for example, stearic acid, oleic acid, arachidic acid, icosenoic acid, behenic acid, erucic acid, lignocenoic acid, tetracosenoic acid and the like are preferable. As the polyglycerin, for example, decaglycerin, hexaglycerin and the like are preferable.

The ester may be of any type such as monoester, diester and triester.
The ester may have an HLB of usually 7 or more, preferably 8 or more, more preferably 10 or more.

Specific examples of the ester that can be used as the aqueous emulsifier of the present invention include decaglycerin stearic acid monoester, hexaglycerin stearic acid monoester, decaglycerin oleic acid monoester, hexaglycerin oleic acid monoester, and decaglycerin elca. Acid monoester, hexaglycerin erucic acid monoester and the like can be preferably used. These aqueous emulsifiers are 1
It can be used in one kind or two or more kinds. Further, these aqueous emulsifiers may be those obtained by a known production method, commercially available products and the like. Therefore, an emulsifier in the form of a mixture of emulsifiers having different polymerization degrees and esterification rates of glycerin that are generally commercially available may be used.

The aqueous emulsifier may be an emulsifier obtained by mixing palmitic acid or palmitoleic acid and an ester of polyglycerin. Further, other emulsifiers can be used in combination as long as the effects of the present invention are not impaired.

The concentration of the aqueous emulsifier can be appropriately determined according to the type of useful substance or aqueous emulsifier used, the type of aqueous phase (inner water phase or outer water phase), and the like. In particular, when it is contained in the inner aqueous phase, it is usually about 0.05 to 50% by weight, preferably 0.5 to 30% by weight. When it is contained in the outer water phase, it is usually about 0.01 to 30% by weight,
It is preferably 0.1 to 10% by weight.

In the present invention, a fatty acid having 18 or more carbon atoms may be contained in the oil phase, if necessary. By containing the above fatty acid, the leakage suppressing effect can be further enhanced.

The above-mentioned fatty acid is not limited, and stearic acid, oleic acid, arachidic acid, icosenoic acid, behenic acid, erucic acid, lignocenoic acid, tetracosenoic acid and the like can be preferably used. These can be used alone or in combination of two or more.

The concentration of the fatty acid can be appropriately determined depending on the type of fatty acid used, the type of aqueous emulsifier, etc., but is usually about 0.01 to 50% by weight, preferably 0.5 to 30% by weight. It should be done.

In the present invention, it is desirable to include an oily emulsifier in the oil phase. By containing the oily emulsifier, excellent effects can be obtained in terms of maintaining stability of the emulsion. The type of oily emulsifier is not limited, but an oily emulsifier having an HLB of 6 or less can be preferably used. Examples of such emulsifiers include glycerin higher fatty acid ester, polyglycerin higher fatty acid ester, polyglycerin condensed ricinoleic acid ester, sucrose fatty acid polyester, polyoxyethylene hydrogenated castor oil, sorbitan higher fatty acid ester, polyoxyethylene sorbitan higher fatty acid ester. Etc. These can be used alone or in combination of two or more. Moreover, these emulsifiers can also use a commercial item.

Particularly in the present invention, polyglycerin condensed ricinolethnic acid ester (hereinafter abbreviated as "PGCR") is most preferable. The PGCR is not particularly limited, and commercial products can be used. PGCR is classified according to the degree of polymerization, and for example, there are tetraglycerin condensed ricinoleic acid ester, decaglycerin condensed ricinoleic acid ester, and the like, both of which can be used in the present invention. These may also be used alone or in combination of two or more.

The concentration when an oily emulsifier is used can be appropriately determined depending on the type of the oily emulsifier used and the like, but is usually about 0.1 to 50% by weight, preferably 1 to 3%.
It may be 0% by weight. Within such a range, more excellent stability can be achieved, which can also contribute to the improvement of the leakage suppression effect. 2. Method for producing stabilized W / O / W emulsion The method for producing the stabilized W / O / W emulsion of the present invention is
A W / O emulsion in which a first aqueous phase containing a useful substance is dispersed in an oil phase is permeated through a porous membrane to be dispersed in a second aqueous phase, thereby making the first aqueous phase an inner aqueous phase, A method for producing a W / O / W emulsion having a second aqueous phase as an external aqueous phase, which comprises, as an aqueous emulsifier, an ester of a fatty acid having 18 or more carbon atoms and polyglycerin as a first aqueous phase and / or a second aqueous phase. It is characterized in that it is contained in the aqueous phase.

In the method of the present invention, the aqueous emulsifier may be contained in at least one of the first aqueous phase and the second aqueous phase. In particular, it is preferable that at least the second aqueous phase contains an aqueous emulsifier. It is also preferable that only the second aqueous phase contains an aqueous emulsifier. The type and concentration of the emulsifier may be set to the same contents as in the above 1. Also,
The oil phase may be set to the same content as in the above 1. First, the W / O emulsion in which the first aqueous phase containing the useful substance is dispersed in the oil phase may be prepared according to a known method or the like.

The first water phase can be prepared by dissolving or dispersing a useful substance in water. The type and concentration of the useful substance may be set according to the contents described above. Also, in the first water phase,
A substance for adjusting the osmotic pressure may be added if necessary. As such a substance, for example, salts such as sodium chloride, calcium chloride, magnesium chloride, iron chloride, sugars such as glucose, lactose, dextrin, and glycerin can be used.

The method of emulsifying the first aqueous phase in the oil phase is not limited and can be carried out by a known emulsification method. For example, a method using a homomixer, a stirrer, a high pressure homogenizer, a porous membrane or the like can be mentioned. in this case,
The average particle size or particle size distribution of the particles that become the inner aqueous phase is W / O /
The W / O of the target W / O / W emulsion can be set as appropriate depending on the use and purpose of use of the W emulsion.
It is desirable that the average particle size is equal to or smaller than the average particle size of the liquid droplets because the leakage suppressing effect can be further enhanced.

The volume ratio of the first aqueous phase to the oil phase is not limited, and the type of aqueous emulsifier or oil phase to be used and the desired W /
It can be appropriately set depending on the use and purpose of use of the O / W emulsion.

The temperature condition in the step of preparing the W / O emulsion may be appropriately set, but it is desirable to carry out at a relatively low temperature in order to further enhance the leakage suppressing effect. Specifically, the temperature is preferably about 0 to 60 ° C, more preferably 1 to 30 ° C, and most preferably 3 to 10 ° C.

Then, the W / O emulsion obtained above is permeated through the porous membrane and dispersed in the second aqueous phase to make the first aqueous phase an inner aqueous phase and the second aqueous phase. A W / O / W emulsion for the external water phase is obtained. If necessary, a substance for adjusting the osmotic pressure may be added to the second aqueous phase. Specifically, those similar to those applicable to the first aqueous phase can be used.

The emulsification method itself using a porous membrane can be carried out according to a known membrane emulsification method. For example, Patent No. 21
The emulsification can be carried out by appropriately using the porous glass membrane and the operating conditions disclosed in No. 06958, Japanese Patent No. 2733729 and the like. A commercial item can also be used for these porous membranes.

The volume ratio of the W / O emulsion and the second aqueous phase is not limited, and is appropriately set according to the type of W / O emulsion used, the intended use of the W / O / W emulsion, the purpose of use, etc. can do.

Also, in the second aqueous phase, a substance for adjusting the osmotic pressure may be added if necessary. Examples of such substances include salts such as sodium chloride, calcium chloride, magnesium chloride and iron chloride, sugars such as glucose, lactose and dextrin, and glycerin.

The temperature conditions in the emulsification process using a porous membrane may be set appropriately according to the types of useful substances, external water phase, etc. used, but in order to further enhance the effect of suppressing leakage, it should be carried out at a relatively low temperature. desirable. Specifically, the temperature is preferably about 0 to 60 ° C, more preferably 1 to 30 ° C, and most preferably 3 to 10 ° C.

In the present invention, the W obtained as described above is used.
The / O / W emulsion can be further permeated through the porous membrane. The number of times of transmission may be once or twice or more. Specifically, W / O on both sides through a porous membrane
It is possible to employ a method in which a / W emulsion is present, and the emulsion is permeated from one side toward the other side, then the emulsion is circulated to one side, and the porous membrane is permeated again. This makes it possible to more effectively subdivide the W / O emulsion. 3. Method for controlling release rate In the present invention, a useful substance can be positively released into the outer water phase by adding an aqueous emulsifier to the outer water phase of the obtained W / O / W emulsion, and the release thereof is also possible. The speed can be controlled. It is also possible to adjust the release start time of the useful substance.

That is, the present invention provides a W / O / W emulsion containing a useful substance in the inner aqueous phase and an aqueous emulsifier in the outer aqueous phase and / or the inner aqueous phase, wherein the aqueous emulsifier is A W / O / W emulsion characterized by being an ester of a fatty acid having 18 or more carbon atoms and polyglycerin is used, and a second aqueous emulsifier (excluding the above aqueous emulsifier) is further added to the outer aqueous phase. It also includes a method of controlling the release rate of a useful substance into the external aqueous phase by adding it.

As the internal water phase, the external water phase and the oil phase, and the aqueous emulsifier which is an ester of a fatty acid having 18 or more carbon atoms and polyglycerin, the same ones as those shown in the above 1 or 2 may be adopted. .

In the method of the present invention, after the W / O / W emulsion is prepared, the second aqueous emulsifier is added to the outer aqueous phase. The second aqueous emulsifier may be any aqueous emulsifier other than the emulsifier of the present invention, and can be appropriately selected from known or commercially available aqueous emulsifiers. For example, esters other than the emulsifier of the present invention can be used. In particular, esters such as polyglycerin lauric acid ester, sucrose lauric acid ester, sucrose stearic acid ester, and decaglycerin caprylic acid ester can be preferably used. These can be used alone or in combination of two or more.

In the method of the present invention, the release rate of the useful substance, the release start time, etc. can be controlled by appropriately changing the type or addition amount of the second aqueous emulsifier. Therefore, for example, when it is desired to absorb a pharmacologically active ingredient into a specific organ in the body (liver, small intestine, etc.), W / O /
By adding a predetermined amount of the second aqueous emulsifier at the time of using the W emulsion (oral use, etc.), it is possible to achieve the predetermined purpose by controlling the release start time and release rate of the component.

[0059]

According to the present invention, since the emulsifier of the present invention is applied to the aqueous phase, it is possible to effectively suppress or prevent leakage of useful substances present in the internal aqueous phase to the external aqueous phase.
Such stable emulsions can be used in a wide range of applications in combination with the fact that the external phase is water (that is, having an external aqueous phase), and various products can be prepared by selecting useful substances to be encapsulated in the internal aqueous phase. It is possible to provide it efficiently.

Further, in the present invention, since the release rate of the useful substance can be controlled by using the second aqueous emulsifier, for example, a W / O / W emulsion in which the useful substance has a sustained release property is provided. It is also possible. Such an emulsion is expected to have a wide range of applications, particularly in the fields of foods, pharmaceuticals, etc.

[0061]

EXAMPLES Examples and comparative examples will be shown below to further clarify the characteristics of the present invention. However, the scope of the present invention is not limited to the scope of the embodiments.

Examples 1 to 5 and Comparative Examples 1 to 5 An extract containing anthocyanin as a main component was produced by purifying an extract from purple sweet potato with an ion exchange resin. Add distilled water to this extract and add Brix (% solids)
The internal water phase was adjusted to 50. Commercial soybean oil 90% by weight
And 10% by weight of polyglycerin condensed ricinoleic acid ester (trade name "CR-310" manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) were mixed to prepare an oil phase. Glucose 10% by weight and 1% by weight of the aqueous emulsifier shown in Table 1 were thermally dissolved in distilled water and cooled to 25 ° C. to obtain an external water phase.

1 part by weight of the inner aqueous phase was added dropwise to 3 parts by weight of the above oil phase, and the mixture was emulsified and dispersed using a homomixer (trade name "PT-45" manufactured by Polytron) to obtain W /
An O emulsion was obtained.

The following aqueous emulsifiers used in Table 1 were used.

Decaglycerin stearic acid ester
Product name "SWA-10D" Hexaglycerin stearate manufactured by Mitsubishi Chemical Foods ... Product name "H
S11 "Decaglycerin erucic acid ester manufactured by Mitsubishi Chemical Foods ... Product name" ER-3
0E ”Mitsubishi Kagaku Foods decaglycerin / oleate ... Product name“ O-1
5D ”Mitsubishi Kagaku Foods made decaglycerin / oleic acid monoester ... Product name“ M
SW-750 "Sakamoto Yakuhin Kogyo decaglycerin / lauric acid ester ... Product name" L-7 "
D "Mitsubishi Kagaku Foods sucrose lauric acid ester ... Product name" L-1695 "Mitsubishi Chemical Foods sucrose stearate ... Product name" S-1670 "
Mitsubishi Kagaku Foods hexaglycerin / lauric acid monoester ... Product name “ML-500” Sakamoto Yakuhin Kogyo decaglycerin / caprylic acid monoester… Product name “M
CA-750 "manufactured by Sakamoto Yakuhin Kogyo Co., Ltd. Then, using 4 parts by weight of the W / O emulsion, 100 parts by weight of the external water phase was press-dispersed through a porous glass membrane (SPG Techno, average pore diameter 1.7 μm). , 25 ℃
A W / O / W emulsion was obtained by carrying out film emulsification in.

The leakage rate of the obtained emulsion was examined. 1 W / O / W emulsion at 5000 rpm
After centrifuging for 0 minutes, the concentration of anthocyanins contained in the separated external water phase was measured, and the measured value was defined as the leakage rate by weight% with respect to the concentration of anthocyanins when all the amounts leaked.
The anthocyanin concentration was 536n by diluting the sample with ethyl alcohol containing 1.25 wt% trifluoroacetic acid.
It was calculated from the absorbance at m using cyanidin-3-chloride as a standard. Table 1 shows the leakage rate of each emulsion.

[0067]

[Table 1]

From the above results, the leakage rate of the comparative example is 54% or more, while the leakage rate of the emulsion of the example is 2%.
It can be seen that it is as low as 5% or less. From this, the present invention W / O
It can be seen that the / W emulsion has an excellent effect of suppressing leakage.

Examples 6 to 9 and Comparative Examples 6 to 11 To 100 parts by weight of a commercially available caramel pigment (trade name "Kokuyo Caramel S" manufactured by Ikeda Saccharification), 100 parts by weight of distilled water was added to prepare an inner aqueous phase (1). Was prepared. Separately, synthetic color red No. 102 was made into a 1% aqueous solution with distilled water to obtain an inner aqueous phase (2). Commercially available soybean oil 90% by weight and PGCR10
An oil phase was prepared by mixing with the weight%. Further, 10% by weight of glucose and the aqueous emulsifier at a rate (% by weight) shown in Table 2 were respectively dissolved in distilled water by heating and cooled to 25 ° C. to prepare an outer water phase.

By adding 1 part by weight of the inner aqueous phase to 3 parts by weight of the above oil phase and using a homomixer (trade name "PT-45" manufactured by Polytron) to emulsify and disperse, W /
An O emulsion was obtained.

The following aqueous emulsifiers were used in Table 2.

Decaglycerin stearic acid ester
Product name "SWA-10D" Hexaglycerin stearate manufactured by Mitsubishi Chemical Foods ... Product name "H
S11 "Mitsubishi Chemical Foods decaglycerin / lauric acid ester ... Product name" L-7 "
D "Mitsubishi Kagaku Foods sucrose lauric acid ester ... Product name" L-1695 "Mitsubishi Chemical Foods sucrose stearate ... Product name" S-1670 "
Next, using 4 parts by weight of the W / O emulsion manufactured by Mitsubishi Chemical Foods, press-dispersed into 100 parts by weight of the external water phase through a porous glass membrane (manufactured by SPG Techno, average pore size 4.7 μm), and 25 ° C.
A W / O / W emulsion was obtained by carrying out film emulsification in.

The leakage rate of the obtained emulsion was examined. 1 W / O / W emulsion at 5000 rpm
Centrifuge for 0 minutes, measure the absorbance of the separated external water phase,
The ratio of the leaked concentration sample to the absorbance was calculated. The absorbance was 284 nm for the inner aqueous phase (1) containing the caramel dye as the encapsulating substance, and 511 nm for the inner aqueous phase (2) containing Red 102 as the encapsulating substance.

[0074]

[Table 2]

From the results of Table 2, the leakage rate of the comparative example is 58%.
In contrast to the above, it can be seen that the embodiment can maintain a low leakage rate of 17% or less.

Test Example 1 Distilled water was added to an extract containing purified anthocyanins as a main component to adjust the Brix (solid content%) to 50 to give an inner aqueous phase. The same oil phase as in Example 1 was used. 10% by weight of glucose and 1% by weight of decaglycerin stearic acid ester (trade name "SWA-10D" manufactured by Mitsubishi Kagaku Foods) were thermally dissolved in distilled water and cooled to 25 ° C to obtain an external water phase.

By adding 1 part by weight of the inner aqueous phase to 3 parts by weight of the above oil phase and using a homomixer (trade name "PT-45" manufactured by Polytron) to emulsify and disperse, W /
An O emulsion was obtained.

Furthermore, 4 parts by weight of the W / O emulsion was used to press-disperse into 100 parts by weight of the external water phase through a porous glass membrane (SPG Techno, average pore size 1.7 μm), and the membrane was prepared at 25 ° C. By emulsifying, W /
An O / W emulsion was obtained.

The obtained W / O / W emulsion was divided into three parts, and sucrose laurate ester (trade name "L-1695" manufactured by Mitsubishi Kagaku Foods) was used as a second aqueous emulsifier for each external water phase. 0.1% by weight, 0.3% by weight and 0.
Each was added so as to have a concentration of 5% by weight. Addition 1
After a lapse of time, the outer aqueous phase was collected, and the leak rate was determined in the same manner as in Example 1. The result is shown in FIG.

From the results shown in FIG. 1, it can be confirmed that the leakage rate of anthocyanins increases as the amount of the second aqueous emulsifier added increases. When the results of Table 1 and Table 2 are combined, it can be seen that the aqueous emulsifier "SWA-10D" exhibits a leakage suppressing effect and the second aqueous emulsifier "L-1695" has almost no leakage suppressing effect. That is, in the case of releasing the active ingredient from the stabilized W / O / W emulsion prepared using an aqueous emulsifier showing a leakage suppressing effect at an arbitrary time, the leakage suppressing effect such as the above "L-1695" can be obtained. Release can be initiated by the addition of no aqueous emulsifier. In this case, the release rate can be controlled by adjusting the addition amount of the second aqueous emulsifier.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between an addition amount (% by weight) of a second aqueous emulsifier and a leakage rate (%) in Test Example 1.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C07H 17/065 C07H 17/065 4G065 (72) Inventor Tadao Nakajima 501 Shioji, Miyazaki, Miyazaki Prefecture (72) Inventor Keiichi Fukui 2193 Miyake, Nishi-city, Miyazaki Prefecture (72) Inventor, Ichigo Matsugano 1483-5 Sakaimeko, Yoshimura-cho, Miyazaki City, Miyazaki Prefecture (reference) 4B035 LE03 LG09 LK13 LP21 4C057 AA06 KK07 4C076 AA18 DD46F EE53F EE54F FF16 AGG45 4 EA11 GA17 MA01 MA04 MA22 NA03 4D077 AB08 AB11 AB12 AC04 BA15 DC27Z DD04X DD36X DD36Z DE02X DE07X DE08X DE09X 4G065 AA01 AB03X AB12X AB32X AB33Y AB35Y BA06 BA07 CA06 DA01 DA02 FA01

Claims (8)

[Claims] 1. A W / O / W containing a useful substance in an inner aqueous phase and an aqueous emulsifier in an outer aqueous phase and / or an inner aqueous phase.
In the emulsion, the aqueous emulsifier is an ester of fatty acid having 18 or more carbon atoms and polyglycerin, W / O / W
Emulsion. 2. The W / O / W emulsion according to claim 1, wherein the oil phase contains a fatty acid having 18 or more carbon atoms. 3. The W / O / W emulsion according to claim 1, wherein the oil phase contains polyglycerin condensed ricinoleic acid ester. 4. The W / O / W emulsion according to claim 1, wherein the useful substance is a water-soluble physiologically active substance. 5. The W / O / W emulsion according to claim 4, wherein the water-soluble physiologically active substance is anthocyanin. 6. A W / O emulsion in which a first aqueous phase containing a useful substance is dispersed in an oil phase is permeated through a porous membrane to be dispersed in a second aqueous phase, whereby the first aqueous phase is internally dispersed. A method for producing a W / O / W emulsion comprising an aqueous phase and the second aqueous phase as an external aqueous phase, comprising an ester of a fatty acid having 18 or more carbon atoms and polyglycerin as an aqueous emulsifier in the first aqueous phase. And / or a W / O / W emulsion which is contained in the second aqueous phase. 7. The method according to claim 6, wherein the W / O / W emulsion is further permeated through the porous membrane. 8. A W / O / W containing a useful substance in the inner water phase and an aqueous emulsifier in the outer water phase and / or the inner water phase.
In the emulsion, the aqueous emulsifier is an ester of fatty acid having 18 or more carbon atoms and polyglycerin, W / O / W
A method of controlling the release rate of a useful substance into the outer water phase by using an emulsion and further adding a second aqueous emulsifier (excluding the above-mentioned aqueous emulsifier) to the outer water phase.