JP5415510B2 - Method for producing oil-in-water emulsion - Google Patents

Description

  The present invention is an inexpensive, safe and safe oil-in-water emulsion composition for food and a method for producing the same, and can be easily made into a substantially transparent oil-in-water microemulsion, and a hydrophobic substance such as a flavor substance can be obtained. The present invention relates to a method for producing an oil-in-water microemulsion for food that can be solubilized and added to food.

Research on microemulsions has developed rapidly in recent years, and many attempts have been made to apply this technology to foods.
For example, as disclosed in Patent Document 1, the water phase is water, the auxiliary surfactant and the polyol are 1: 1 to 4, the oil phase is the solvent and the auxiliary solvent is 1 to 2: 1, and the oil phase and the surface activity. There is a liquid concentrate in which the agent has a self-assembled structure of 1: 1 to 2.

  Alternatively, as disclosed in Patent Document 2, the sucrose fatty acid ester of HLB 16-19 or polyglycerin fatty acid ester and lysolecithin are contained in the flavor and stirred at 3000-10000 rpm with a homomixer.

  Alternatively, as disclosed in Patent Document 3, a liquid or paste comprising a seasoning component and 0.1 to 50% by mass of oil and fat in an oil droplet state having an average particle size of 1 μm or less based on the total amount of the composition There is a seasoning composition.

  On the other hand, research on the phase behavior of microemulsions using fatty acids has been actively conducted in recent years. For example, non-patent document 1 study on liquid micellar discontinuous cubic mesophase from monooleic acid / ethanol / water mixture; non-patent document 2 vesicle formation in aqueous dispersion of monoolein and sodium oleate and others Research on phase structure in monoolein aqueous solution system consisting of sodium oleate and oleic acid mixture of Non-Patent Document 3; Study on structure formation of fatty acid arginine in KCl aqueous solution of Non-Patent Document 4; Has been.

  These Non-Patent Documents 1 to 4 are basic studies on simple two-phase and three-phase system behaviors using a single fatty acid, such as complex systems such as constituent fatty acids of fats and oils used in foods, foods The phase behavior under strong pH buffering ability in the components is quite different.

Special table 2005-532049 gazette Japanese Patent No. 3419351 Japanese Patent No. 3162554

Colloids Surf., Vol. 299, No. 1-3, P133-145 J. Colloid Interface Sci., Vol. 257, No. 2, P310-320 Langmuir, Vol. 17, No. 25, P7742-7751 Proceedings of the Colloid and Interface Chemistry Conference (2005) P99

  However, among the conventional techniques described above, the conventional techniques disclosed in Patent Documents 1 and 2 are based on the premise that a strong surfactant that cannot be used for foods or an emulsifier that is permitted for foods is used. It has become. However, recent consumer preferences for safe and secure foods tend to avoid even food additives that have been evaluated for safety, and cannot be said to be a method that sufficiently satisfies consumer needs.

  Furthermore, in patent document 3, it is the technique aiming at providing the rich taste derived from fats and oils to food, and since it is not microemulsified, when added to liquid food etc., it becomes cloudy, The merchandise value is greatly impaired.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a transparent oil-in-water emulsion by using a combination of materials acceptable as food without using a surfactant or an emulsifier.

In order to achieve the above object, the present invention provides triglycerin fatty acid ester with a lipase that hydrolyzes two of the three fatty acid residues to obtain a fatty acid, water, the fatty acid, alcohol And basic amino acid are mixed so that the mass composition ratio of fatty acid / water is 1 or less and the mass composition ratio of fatty acid / alcohol is less than 1, and chitosan or a degradation product of chitosan or glucosamine is added . Provided is a method for producing an oil-in-water emulsion, characterized in that the pH is adjusted to a range of 6 to 8 to obtain an oil-in-water emulsion that does not contain a surfactant and an emulsifier .

  In the method for producing an oil-in-water emulsion of the present invention, it is preferable to obtain an oil-in-water emulsion by mixing each material and permeating the porous membrane.

  In the method for producing an oil-in-water emulsion of the present invention, it is preferable to add a protein or a protein degradation product before adjusting the pH of the emulsion.

The method for producing an oil-in-water emulsion of the present invention comprises mixing an alcohol and a basic amino acid so that the mass composition ratio of fatty acid / water is 1 or less and the mass composition ratio of fatty acid / alcohol is less than 1. A substantially transparent oil-in-water emulsion can be produced by adjusting the pH of the emulsion to a range of 6-8.
In the method for producing an oil-in-water emulsion of the present invention, a fatty acid that is one of the essential components is obtained by allowing a triglycerin fatty acid ester to act on a lipase that hydrolyzes two of the three fatty acid residues. Fatty acids can be obtained from cheap and safe raw materials such as vegetable oils.
In the method for producing an oil-in-water emulsion of the present invention, each material is mixed and permeated through a porous membrane to obtain an oil-in-water emulsion, thereby making the emulsion transparent and stable in a weakly acidic region near pH 6. be able to.
In the method for producing an oil-in-water emulsion of the present invention, before the pH of the emulsion is adjusted, protein or protein degradation product, chitosan or chitosan degradation product or glucosamine may be added to the emulsion to dilute with water. An emulsion that does not become cloudy can be produced.

It is a graph which shows the comparison result of the limonene residual rate in Example 5. 6 is a graph showing measurement results of TO solubility in an emulsion in Example 6.

  The oil-in-water emulsion of the present invention comprises water, a fatty acid, an alcohol, and a basic amino acid, the mass composition ratio of fatty acid / water is 1 or less, and the mass composition ratio of fatty acid / alcohol is less than 1, The pH is in the range of 6-8.

  In the present invention, water that can be used for food production, for example, tap water, sterilized groundwater, mineral water, ion exchange water, distilled water, and the like can be used.

  In the oil-in-water emulsion of the present invention, the fatty acid indicates a hydrocarbon monocarboxylic acid, and is not particularly limited as long as it is a constituent fatty acid of fats and oils generally used for food. However, when the fatty acid is a mixture of two or more fatty acids, the fatty acid composition of the fatty acid mixture preferably has a composition ratio of a saturated fatty acid having 18 or more carbon atoms (eg, stearic acid) of 10% by mass or less. If the composition ratio of the saturated fatty acid exceeds 10% by mass, the produced emulsion may be clouded. In the oil-in-water emulsion of the present invention, the fatty acid content is preferably 20% by mass or more. When the content of fatty acid is 20% by mass or more, when a hydrophobic substance such as triglycerin ester is added to the oil-in-water emulsion, the solubility of the hydrophobic substance is remarkably increased.

  In the oil-in-water emulsion of the present invention, alcohol that can be used for food production can be used as alcohol, and ethanol is most preferable. In the present invention, the alcohol content is preferably 10% by mass or more.

  In the present invention, basic amino acids are histidine, arginine, lysine, and the like, and these can be used alone or in a mixed state. As this basic amino acid, a purified basic amino acid may be added, and an extract or protein hydrolyzate containing the basic amino acid may be used. The amount of basic amino acid added in the oil-in-water emulsion of the present invention is not particularly limited as long as it can be substantially dissolved, but is preferably in the range of 0.01 to 1.00% by mass. If basic amino acids are not contained in an oil-in-water emulsion, the pH of the system needs to be higher than 8 in order to produce a stable emulsion. Disappear. If an amount exceeding the solubility of the basic amino acid is added, the undissolved amino acid will settle, and naturally the precipitated basic amino acid will not have an emulsion stabilizing effect, resulting in increased costs, bitterness and Since taste is seen, it is not preferable.

  In the present invention, the mass composition ratio of the three components of water, fatty acid, and alcohol is such that the mass composition ratio of fatty acid / water is 1 or less and the mass composition ratio of fatty acid / alcohol is less than 1. When the mass composition ratio of fatty acid / water exceeds 1, oily water is easily separated. Also, when the mass composition ratio of fatty acid / alcohol exceeds 1, oil and water are easily separated.

  The oil-in-water emulsion of the present invention has a system pH in the range of 6-8. If the pH is less than 6, the average particle diameter of the oil droplets becomes large and becomes cloudy, or the oil and water are separated and an emulsion cannot be formed. On the other hand, when the pH exceeds 8, there is no big problem in the stability of the emulsion, but when put in the oral cavity, the irritation is strong and it is not preferable as a food.

  A monoglycerin fatty acid ester can be added to the oil-in-water emulsion of the present invention. As monoglycerin fatty acid esters, various monoglycerin fatty acid esters that are acceptable for food production can be used, but triglycerin fatty acid esters used in foods are divided into two of the three fatty acid residues. It is particularly preferable that a lipase that is hydrolyzed is allowed to act and is produced, so that no addition of food additives is required. In this case, the composition ratio of the monoglycerin fatty acid ester is preferably 50 mol% or less of the fatty acid added or produced by lipase.

  The oil-in-water emulsion of the present invention may contain a hydrophobic substance. Hydrophobic substances include fragrance ingredients such as limonene, oil-based synthetic flavors, natural flavors extracted from natural products using supercritical carbon dioxide, fat-soluble vitamins such as vitamin E and vitamin A, docosahexaenoic acid (DHA) ), Polyunsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA), glycerin esters thereof, and triglycerin fatty acid esters. Preferred triglycerin fatty acid esters include edible oils such as salad oil, soybean oil, cottonseed oil, olive oil, corn oil, and sesame oil. When a hydrophobic substance is added to the oil-in-water emulsion of the present invention, the amount added is preferably 10% or less, more preferably 5% or less, based on the amount of fatty acid in the oil-in-water emulsion. If the hydrophobic substance is added within the above range, the hydrophobic substance dissolves in the oil-in-water emulsion without oil / water separation, and the transparent property can be maintained.

  Furthermore, 1 type, or 2 or more types selected from the group which consists of protein or the degradation product of protein, chitosan, xanthine, and glucosamine can be added to the oil-in-water emulsion of this invention. Examples of the protein or protein degradation product include water-soluble proteins or degradation products among various proteins that are acceptable for food production. For example, gelatin is preferable. Chitosan, xanthine, and glucosamine can be appropriately selected from various commercially available products. By adding these proteins or protein degradation products, chitosan, xanthine, and glucosamine to the oil-in-water emulsion of the present invention, the stability of the emulsion is improved, and an emulsion that does not become cloudy even when diluted with water can be obtained. it can.

  In the oil-in-water emulsion of the present invention, the average particle diameter of oil droplets in the emulsion is preferably 200 nm or less. By setting the average particle size of the oil droplets to 200 nm or less, an oil-in-water emulsion that is substantially transparent and stable for a long time can be produced.

  In the method for producing an oil-in-water emulsion of the present invention, water, fatty acid, alcohol, and basic amino acid have a fatty acid / water mass composition ratio of 1 or less and a fatty acid / alcohol mass composition ratio of less than 1. And the pH of the system is adjusted in the range of 6 to 8 to obtain the oil-in-water emulsion according to the present invention.

In the method for producing an oil-in-water emulsion of the present invention, the procedure, production equipment and the like for producing a uniform emulsion by mixing the components are not particularly limited. A typical manufacturing procedure is illustrated as follows.
(A) First, a predetermined amount of basic amino acid is added and dissolved in a predetermined amount of water,
(B) Then, while stirring this water, a predetermined amount of fatty acid is added,
(C) Then, a predetermined amount of alcohol is added with further stirring,
(D) Then, while monitoring the pH of the obtained emulsion, a pH adjusting agent such as sodium hydroxide is added to adjust the pH of the system to a desired pH value in the range of 6-8, and A substantially clear oil-in-water emulsion is obtained.
This manufacturing procedure is merely an example, and the manufacturing method of the present invention is not limited to this example.

  As a preferred embodiment of the production method of the present invention, it is possible to obtain an oil-in-water emulsion by mixing each material and permeating through a porous membrane. As this porous membrane, a commercially available alumina filter or the like can be used, and it is preferable to carry out a process of emulsifying the membrane by sequentially passing the mixed solution through a plurality of stages of filters in which the pore diameter gradually decreases.

  In the method for producing an oil-in-water emulsion of the present invention, a lipase that hydrolyzes two of the three fatty acid residues is allowed to act on a triglycerin fatty acid ester in order to obtain a fatty acid that is one of the essential components. It can also be decomposed to produce fatty acids, which can be mixed with other essential ingredients to produce an oil-in-water emulsion. Thereby, fatty acids can be obtained from inexpensive and safe raw materials such as vegetable oils.

  Triglycerin fatty acid esters include edible oils such as salad oil, soybean oil, cottonseed oil, olive oil, corn oil, and sesame oil. As the lipase, it is desirable to use a lipase that hydrolyzes two of the three fatty acid residues of triglyceride. Examples of such lipases include lipases produced by Candida rugosa. This lipase hydrolyzes the ester bonds at the 1-position and 2-position of triglyceride to liberate fatty acids. The reaction conditions for the lipase may be the optimum conditions for the lipase to be used, and are not particularly limited. In general, the lipase is used at room temperature to 50 ° C., and the pH is around 5 to 8.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by an Example.
Unless otherwise specified,% notation in Examples and Comparative Examples indicates mass%.
Each measurement condition in the examples is as follows.

<Measurement method of average particle diameter of oil droplets in emulsion>
The average particle diameter of the oil droplets in the emulsion was measured by Zetasizer Nano ZS (manufactured by Marman).

<Emulsion properties>
The sample emulsion was allowed to stand for 24 hours, and the transparency, presence / absence of oil / water separation, and presence / absence of white turbidity were examined visually. Moreover, when it investigated about 48 hours after room temperature standing or one month later, it described as "property 2" in the table | surface, and indicated the room temperature standing time together.

[Example 1]
Dissolve 0.1 parts by mass of histidine (Wako Pure Chemical Industries, reagent special grade) in ion-exchanged water, and add 5, 10, 20, or 30 parts by mass of oleic acid (made by Wako Pure Chemical Industries, reagent special grade) Thereafter, while stirring with a stirrer, 40 parts by mass of ethanol (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent) was added, and the pH of the system was adjusted with sodium hydroxide. 1-No. 4 emulsions were made. In addition, as a comparative example, a case where histidine was not used (Comparative Example 1) and a case where ethanol was not used (Comparative Example 2) were similarly produced.

  No. shown in Table 1. 1-No. 4 and the samples of Comparative Examples 1 and 2, the fatty acid / water mass composition ratio, the fatty acid / alcohol mass composition ratio, the average particle diameter, and the properties were compared. The results are shown in Table 2. The pH of each emulsion was as shown in Table 2.

As shown in Table 2, in Comparative Example 1 containing no histidine, even when the pH was adjusted to 9, separation of oil and water was observed after 24 hours of standing. Moreover, also in the comparative example 2 which does not contain alcohol, isolation | separation of oil-water was seen.
On the other hand, no. 1-No. In No. 4, a transparent oil-in-water emulsion was formed, and no change in state was observed for more than 1 month when allowed to stand at room temperature.

(Effective range of pH)
No. 1 prepared in Example 1. For the emulsion having the same composition as No. 4, the average particle size and the properties (stability) of the emulsion when the pH of the system was changed as shown in Table 3 were examined. The results are shown in Table 3.

As shown in Table 3, the emulsion having a pH of less than 6 was unstable, and oil-water separation was observed within 24 hours of standing.
Emulsions having a pH of 6 or more gave stable and small-sized emulsions.
When the pH was over 9, there was no major problem in the stability of the emulsion. Rather, the average particle size was small and stable, but when placed in the oral cavity, the irritation was strong and the food was not preferred.

(Effective range of alcohol)
No. of Example 1 The ratio of water and ethanol in the emulsion of No. 1 was changed as shown in Table 4, and other than that, in the same manner as in Example 1, No. 1 was obtained. 5-No. 8 emulsions were made. The pH of each emulsion was as shown in Table 5.

  No. shown in Table 4 5-No. For each sample of No. 8, the mass composition ratio of fatty acid / water, the mass composition ratio of fatty acid / alcohol, the average particle diameter, and the properties are shown in Comparison with one emulsion. The results are shown in Table 5.

  As shown in Table 5, the alcohol usually used as a demulsifier is a material for producing a stable emulsion having a fatty acid / alcohol mass composition ratio of less than 1 in the present invention. It was also found that the emulsion was further stabilized when the composition ratio of alcohol was 10% by mass or more.

[Example 2]
As shown in Table 6, No. 1 prepared in Example 1 was obtained. In the emulsion of No. 4, an emulsion (No. 9) in which arginine (made by Wako Pure Chemical Industries, special grade) is added instead of histidine, and an emulsion (No. 9) made by adding lysine (made by Wako Pure Chemical Industries, special grade). 10) were produced respectively. The pH of the emulsion was as shown in Table 7.

  No. For each of 9-10 emulsions, the average particle size and properties were examined. The results are The results are shown in Table 7 together with the results of emulsion No. 4.

  As shown in Table 7, even when basic amino acids other than histidine (arginine and lysine) were used, a transparent emulsion could be produced as in the case of histidine.

[Example 3]
No. of Example 1 To the emulsion having the same composition as in No. 4, 0.1 part by mass of glycerol monooleate was added. Eleven emulsions were made.

  The pH of each emulsion was as shown in Table 9. No. 4 and no. For the emulsion No. 11, the average particle size, properties (after 24 hours at room temperature) and properties 2 (after 1 month at room temperature) were examined. The results are shown in Table 9.

  As shown in Table 9, the emulsion of the present invention can prepare a more stable emulsion by containing a monoglycerin fatty acid ester.

[Example 4]
No. of Example 1 Based on the composition of No. 4, emulsions (No. 12 to No. 14) were prepared by replacing part of oleic acid with stearic acid, which is a saturated fatty acid having 18 carbon atoms.
Dissolve 0.1 parts by mass of histidine (made by Wako Pure Chemical Industries, Ltd., reagent grade) in ion-exchanged water, add oleic acid (made by Wako Pure Chemical Industries, Ltd., reagent grade) according to the composition ratio in Table 10, and then use a stirrer. While stirring, stearic acid (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) was added according to the composition ratio. The temperature of the system was set to 70 ° C., stearic acid was dissolved, 40 parts by mass of ethanol (made by Wako Pure Chemical Industries, Ltd., reagent special grade) was added, and the mixture was sealed and stirred so that ethanol did not volatilize. When the heating was stopped and the temperature of the system reached 40 ° C., the pH of the system was adjusted to 6.3 using sodium hydroxide. 12-No. 14 emulsions were made.

  No. obtained 12-No. The average particle size and properties of 14 emulsions were examined. The results are The results are shown in Table 11 together with the results of emulsion No. 4.

  As shown in Table 11, when a saturated fatty acid having 18 or more carbon atoms was contained in an amount of 10% by mass or more of the fatty acid composition, a white precipitate was gradually generated as the temperature decreased, and it could not be said to be a stable emulsion.

[Example 5]
Comparative Example 1 prepared in Example 1 and No. Add 1% of limonene (special grade reagent, manufactured by Wako Pure Chemical Industries, Ltd.) to each emulsion of No. 1, stir with an open stirrer, and sample over time to determine the residual rate of limonene (%) by high performance liquid chromatography. Measured by chromatography (HPLC). The results are summarized in the graph of FIG.

  From the results shown in FIG. 1, in Comparative Example 1, the limonene remaining rate after one week was almost 0%, whereas the No. In 1, there is a residual rate close to 90%, and it is clear that the emulsion according to the present invention incorporates a hydrophobic substance into the emulsion and exhibits high sustained release.

[Example 6]
No. 1 prepared in Example 1. 1-No. Glycerol trioleate (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade; hereinafter abbreviated as TO) was added to the oil-in-water emulsion of No. 4, and the amount that could be incorporated into the emulsion and maintained transparent was measured. The measurement results are shown in FIG. 2 as TO solubility (μl / 100 ml).

  From the result of FIG. 2, when the constituent fatty acid content of the emulsion is 20%, the inflection point of the solubility with respect to TO is shown, and when the constituent fatty acid is 20% or more, the TO solubility is rapidly increased.

[Example 7]
0.1 parts by mass of histidine (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) and 0.1 parts by mass of lipase AY-30 (manufactured by Amano Enzyme) are dissolved in ion-exchanged water, and salad oil (manufactured by Nisshin Eulio) 30 After adding 15 parts by mass and stirring with a stirrer, after 15 hours at room temperature, 40 parts by mass of ethanol (made by Wako Pure Chemical Industries, Ltd., reagent grade) is added, and the pH of the system is adjusted with sodium hydroxide. Adjusted to 5.

  The composition and properties of the emulsion of Example 7 produced as described above were as shown in Table 13 and Table 14.

  In the emulsion of Example 7, the total amount of saturated fatty acids having 18 or more carbon atoms was 3% in the fatty acid composition.

[Example 8]
While stirring with a stirrer, salad oil was added to the oil-in-water emulsion prepared in Example 7 at the addition amount shown in Table 15, and the average particle size and properties of the emulsion at that time were observed.

  Usually, in order to maintain a transparent state, it is desirable to set the emulsion particle size to 50 nm or less which is not more than the visible light wavelength. However, as in this example, the constituent fatty acid composition of the emulsion and the fatty acid of the added hydrophobic substance When the composition is close, the refractive index with respect to light is close, so that even if the average particle size is about 200 nm, a transparent and safe emulsion can be obtained.

[Example 9]
In a 10% aqueous solution of bonito soup extract NP-40 (manufactured by Nihon Suisan Co., Ltd.) having a histidine content of 1.6%, 0.1% of lipase AY-30 is dissolved, and stirred with a stirrer, 30% salad oil is added. Added. After 15 hours at room temperature, 40% ethanol was added and the pH was adjusted to 6.5 with sodium hydroxide. As a result, a brownish brown liquid color derived from bonito soup extract was obtained, and a transparent emulsion similar to Example 7 was obtained.

  Histidine is an amino acid contained in a large amount in foods, in addition to having a strong buffer capacity near neutrality, and is particularly contained in a large amount in migratory fish. Therefore, since histidine can be used in the present invention as a food-derived component without adding histidine again, histidine is particularly preferable in the present invention among basic amino acids.

[Example 10]
0.1 parts by mass of histidine (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) and 0.1 parts by mass of lipase AY-30 (manufactured by Amano Enzyme) are dissolved in ion-exchanged water, and salad oil (manufactured by Nisshin Eulio) 30 After adding 15 parts by mass and stirring with a stirrer for 15 hours at room temperature, 40 parts by mass of ethanol (made by Wako Pure Chemical Industries, Ltd., reagent grade) is added, and 10% aqueous solution of fish gelatin (manufactured by Maruha) 10 Part by weight was added. The pH of the system was adjusted to 6.5 using sodium hydroxide to produce the emulsion of Example 10.

In the emulsion of Example 7, the emulsion itself is stable. However, when the emulsion is diluted with water, the equilibrium of the system is lost and the mixture becomes white turbid, followed by oil-water separation.
In contrast, the emulsion of Example 10 was obtained by adding a protective colloid component such as a protein before adjusting the pH of the system, so that an emulsion that did not become cloudy was obtained even when the prepared emulsion was diluted with water. .

[Example 11]
0.1 parts by mass of histidine (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) and 0.1 parts by mass of lipase AY-30 (manufactured by Amano Enzyme) are dissolved in ion-exchanged water, and salad oil (manufactured by Nisshin Eulio) 30 After adding 15 parts by mass and stirring with a stirrer, after 15 hours at room temperature, 40 parts by mass of ethanol (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) is added, and water-soluble chitosan (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) ) Or 10 parts by mass of a 10% aqueous solution of glucosamine (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent). The pH of the system was adjusted to 6.5 using sodium hydroxide to produce the emulsion of Example 11.

Similar to Example 10, even when chitosan or glucosamine was added, it was possible to prevent white turbidity due to dilution.
These proteins and chitosan are high molecular compounds having NH ₂ -groups, which interact with the carboxyl groups of fatty acids contained in the emulsion of the present invention, and are thought to contribute to the stabilization of the emulsion. Objects are also considered to show similar effects.

[Example 12]
In the specification of the effective pH range of Example 1 (see Table 3), a pale white cloudy emulsion having a pH of 6 was passed through a membrane filter (MIPORE) having a pore size of 0.45 μm, and then an alumina filter (WHATMAN) having a pore size of 0. 2 μm, 0.1 μm, and 0.02 μm membranes were sequentially passed. As a result, the pale white emulsion became a transparent emulsion, and the average particle size at that time was 38 nm.

  Ordinary foods are often weakly acidic with a pH of around 6. By allowing the emulsion to pass through a porous membrane, it was possible to achieve transparency and stabilization of the emulsion at a pH in the weakly acidic region.

  The present invention is an inexpensive, safe and safe oil-in-water emulsion composition for food and a method for producing the same, and can be easily made into a substantially transparent oil-in-water microemulsion, and a hydrophobic substance such as a flavor substance can be obtained. The present invention relates to a method for producing an oil-in-water microemulsion for food that can be solubilized and added to food.

Claims (3)

A triglycerin fatty acid ester is allowed to act on a lipase that hydrolyzes two of the three fatty acid residues to obtain a fatty acid. Water, the fatty acid, alcohol, and a basic amino acid are mixed with fatty acid / water. The mass composition ratio is 1 or less and the mass composition ratio of the fatty acid / alcohol is less than 1, and after adding chitosan or a degradation product of chitosan or glucosamine, the pH of the system is adjusted to a range of 6-8. A method for producing an oil-in-water emulsion, characterized by obtaining an oil-in-water emulsion that does not contain a surfactant and an emulsifier .   The method for producing an oil-in-water emulsion according to claim 1, wherein each material is mixed and permeated through a porous membrane to obtain an oil-in-water emulsion.   The method for producing an oil-in-water emulsion according to claim 1 or 2, wherein a protein or a degradation product of the protein is added before adjusting the pH of the emulsion.

Images