JPH0956351A - Oil-in-water type emulsion and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject emulsion preservable at normal temperatures even without blending high-melting oil-and-fat, good in flavor and palate feeling such as meltability-in-mouth, thus suitable for e.g. whipped cream, by decomposing, with a protease, a protein component compounded with or adsorbed to an oily phase. SOLUTION: In an emulsion made by emulsifying an oily phase and an aqueous phase, a protein component compounded with or adsorbed to the oily phase is decomposed by a protease (pref. metalloprotease derived from Bacillus bacteria). The oil-and-fat constituting the oily phase is pref. hardened palm oil. The aqueous phase comprises water, protein, and, according as necessary, saccharide(s) and an emulsifier; in this case, the protein is pref. powdery and/or liquid lactoprotein, fractionated product and/or lactoproteinic agent thereof. The amount of the protease to be added is pref. 0.0001-5wt.% based on the objective whole emulsion. It is preferable that the objective emulsion be composed of 10-40wt.% of the oily component and 60-90wt.% of the aqueous component and 200-2000cp in viscosity at 5 deg.C.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an oil-in-water emulsion and a method for producing the same. More specifically, the present invention is used as a topping for cakes, breads, desserts or the like, or whipped as a filling material, and is particularly suitable as a foaming oil-in-water emulsion, and is excellent in heat-resistant shape retention foaming property. It relates to an oil-in-water emulsion. It also has a sour taste (pH
3.0 or more) It can be used by mixing with dairy products such as jams, fruit sauces and yogurt. Especially, it is suitable as a foaming oil-in-water emulsion and has excellent heat-resisting and acid-resistant foaming properties. It also relates to oil-in-water emulsions.

[0002]

2. Description of the Related Art Whipped cream consisting of an oil-in-water emulsion, which is used as a topping and filling material in cakes, breads, desserts, etc., does not impair the good flavor and texture during storage, and retains its shape and plasticity. It is required to have good foamability and shape-retaining property without being formed. Therefore, conventionally, this type of cream has been distributed at a low temperature, and as a cream in a room temperature distribution form, a water-in-oil emulsion such as butter cream has been exclusively used. In recent years, with the diversification of tastes and changes in distribution form, there has been a demand for an oil-in-water emulsion that can be distributed at room temperature, and a foaming oil-in-water emulsion sweetening cream has come to be used instead of butter cream and the like. It was Such a foamable oil-in-water emulsion has a good shape retention property at room temperature by blending a high melting point oil and fat such as coconut oil, palm kernel oil and its hardened oil, or a thickening polysaccharide. You can get things, but on the other hand,
It is known that the texture such as melting in the mouth becomes extremely bad. Further, as a method of increasing the heat-resisting property, focusing on the fat crystal amount and the emulsifier from the viewpoint of improving the emulsion stability,
Methods using specific triglycerides and emulsifiers have also been proposed (for example, JP-A-54-37858 and JP-A-58-116647).
No. 61-141856), only heat resistance at 20 to 25 ° C. was imparted, and the target level was not reached. JP-A-4-88944 proposes an oil-in-water emulsified oil / fat composition containing 10% by weight or more and less than 30% by weight of diglyceride in the oil phase. The unsaturated fatty acid is used as the main constituent fatty acid of (1), and its only purpose is to improve the milky taste and richness. On the other hand, the foamable oil-in-water emulsion contains a protein component as its constituent component. Since the protein components present in this emulsion are generally considered to contribute to the stabilization of the alveolar membrane, modifying these protein components improves the physical properties such as shape retention. there is a possibility. However, no example has yet been reported in which the heat-resistant shape retention of the foamable oil-in-water emulsion was improved by modifying the protein component, and the method of enzymatically decomposing the aqueous phase protein (especially Kaisho 64-23
No. 867) and a method using an enzyme-treated whey protein (JP-A-2-257838), there are only known examples of improving acid resistance. Also, as the fields of use of sugar-type oil-in-water emulsions have expanded with changes in taste, jams with acidity (pH 3 or higher),
It is also increasingly used as a mixture with dairy products such as fruit sauces and yogurt. As the characteristics required for such a special application, the heat-resistant shape retention of the above cream,
In addition to texture such as melting in the mouth, acid resistance, that is, quality that does not cause quality deterioration even when used in combination with these sour components is required. As a method for imparting such acid resistance, there are the above-mentioned JP-A-64-23867 and JP-A-2-257838.
Examples of such methods include a method of enzymatically decomposing a protein in an aqueous phase as described in Japanese Patent Publication No. 60-242, and a method of using an enzyme-treated whey protein. Is slightly improved, but the performance is insufficient, and the present situation is that it does not have the effect of improving the heat-resisting shape retention. None of them has been reported to improve the heat-resisting shape retention.

[0003]

As described above, no example has been reported yet in which the heat-resistant shape retention of the foamable oil-in-water emulsion is improved by modifying the protein. Moreover, the conventional protein modification technology by enzymatic decomposition cannot easily suppress the production of free amino acids, and is not very practical. Therefore, there is a demand for a protein modification technique that can easily control the reaction without changing the flavor. Furthermore, if a modified protein with improved heat-resisting and shape-retaining properties can be obtained by using these techniques, it can be stored at room temperature without the addition of high-melting oils and fats. It is possible to develop foods using type emulsion. The present invention has been devised in view of the above problems, and an object thereof is to provide an oil-in-water emulsion excellent in heat-resisting shape retention by a protein modification technique. Further, the present invention is to provide a sweetened type oil-in-water emulsion in which the cream after whipped has excellent acid resistance, and also excellent in heat-resisting shape retention, and further improved in mouthfeel and other textures. It is intended to provide an oil-in-water emulsion.

[0004]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that in an emulsion obtained by emulsifying an oil phase and an aqueous phase, a complex or an oil phase is formed with the oil phase. It was found that by decomposing the adsorbed protein component with protease, it is possible to produce an oil-in-water emulsion having a stable shape retention property at room temperature by the generated decomposing peptide, and the glycerin monofatty acid ester is added to the base oil. By adding protease to the emulsion obtained by adding glycerin difatty acid ester and decomposing the protein component, the original fat-and-oil dissolution behavior (physical properties reflected in mouthfeel such as mouthfeel) is hardly impaired. The target heat-resisting shape can also be imparted. Furthermore, the addition of dairy products such as jams, fruit sauces, and yogurts that have a sourness (pH 3.0 or more) has no effect on the physical properties, etc., and found the effect of further enhancing the flavor of the sour material, and completed the present invention. It is a thing. That is, the present invention is an oil-in-water emulsion characterized in that in an emulsion obtained by emulsifying an oil phase and an aqueous phase, a protein component complexed with the oil phase or adsorbed to the oil phase is decomposed with a protease. Is a manufacturing method of. In addition, the present invention provides a protein component complexed with the oil phase or adsorbed to the oil phase in a protease in an emulsion obtained by emulsifying an oil phase containing a glycerin monofatty acid ester and a glycerin difatty acid ester and an aqueous phase. Is a method for producing an oil-in-water emulsion, which is characterized in that it is decomposed. In the present invention, particularly preferred cases are those in which the oil-in-water emulsion is a foaming oil-in-water emulsion and when the oil-in-water emulsion is for whipped cream. Further, the ratio of the oil phase and the water phase in the present invention is emulsification /
It is not particularly limited as long as it can be dispersed.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The oil-in-water emulsion of the present invention and the method for producing the same are described below. First, the oil and fat used in producing the oil-in-water emulsion may be any oil and fat as long as it is an animal or vegetable oil and fat that has been used in the production of creamy oil and fat compositions and the like, for example, rapeseed oil, soybean oil, Examples include sunflower seed oil, cottonseed oil, peanut oil, corn oil, safflower oil, sesame oil, evening primrose oil, palm oil, cacao butter, palm oil, palm kernel oil, milk fat, beef tallow, lard, fish oil, whale oil, and the like. Suitable are oils alone or mixed oils, or processed oils and fats that have been hardened, fractionated, transesterified or the like. Among these oils and fats, a hardened palm oil having a sharp melting behavior at a certain temperature and having a good mouthfeel of the obtained cream is preferable, and in the present invention, a conventional oil-in-water emulsion is used. Blending materials such as emulsifiers, stabilizers (various salts), flavors and essences that have been used can be used as they are. Examples of the emulsifier used in the present invention include soybean lecithin, sucrose fatty acid esters, di-polyglycerin fatty acid esters, sorbitan fatty acid esters, citric acid, organic monoglycerides such as lactic acid or succinic acid, and propylene glycol aliphatic ester. Can be illustrated. Among these emulsifiers, a hydrophilic emulsifier is used in the aqueous phase and a lipophilic emulsifier is used in the oil phase, respectively, or they are used in an appropriate combination. The emulsifier is usually contained in the emulsion in an amount of 0.1 to 1.0% by weight. However, the emulsifier is not always essential in the present invention.
That is, it is known that proteins, especially milk proteins used in creams, have an emulsifying ability, and in the present invention, only milk proteins can be obtained without adding a commonly used emulsifier such as the above-mentioned sucrose fatty acid esters. Depending on its presence, it can form an emulsion and can possibly make a whipped cream.

Examples of the stabilizer include alkali metal salts of phosphoric acid (hexametaphosphoric acid, diphosphoric acid, etc.) and citric acid, gums such as guar gum, gum arabic, xanthan gum, carrageenan, locust bean gum, and the like. CMC or the like can be used. Examples of flavors and essences include milk flavor, vanilla flavor, and vanilla essence. Further, in the present invention, a sugar addition type emulsion to which sugar and / or sugar alcohol is added may be used. Examples of sugars used in this case include glucose, lactose, maltose, and sucrose, and examples of sugar alcohols include:
For example, sorbitol, maltitol, mannitol, xylitol and the like can be mentioned. They are,
They may be used alone or in combination of two or more. The sugar and / or sugar alcohol is usually 10 to 10 in the emulsion.
50% by weight, preferably 20-50% by weight.

[0007] Next, the protein used in the present invention is conventionally known to be complexed with or adsorbed to lipids,
And any protein may be used as long as it is a protein that can be enzymatically treated with a protease, for example, milk protein, vegetable protein, animal protein, or the like, or a protein preparation comprising these, for example, skim milk powder, whole milk powder, casein, Examples include one or more selected from whey protein, soybean powder, serum protein, fish meat powder, egg white powder, egg yolk powder, and the like.
Particularly, powdered and / or liquid milk proteins, fractions thereof and / or milk protein agents are preferable.

Next, in the present invention, the enzyme used for the hydrolysis of the protein component is a protease, and the kind thereof may be any as long as it has a hydrolytic activity in the emulsion, trypsin, Chymotrypsin, papain, bromelain, metalloproteases (Kao Corporation) derived from Bacillus bacteria, protease A "Amano", protease M "Amano",
Protease N "Amano" (above, Amano Pharmaceutical Co., Ltd.),
Examples include protin AC10F, protin FN, protin FA, protin P (above, Daiwa Kasei Co., Ltd.), subtilisin, thermolysin and the like, and these may be used alone or in combination of two or more, but preferably Bacillus (Ba
Cillus) -derived metalloproteases, protease A "Amano", protin FN, and bromelain are good in that the heat-resisting and shape-retaining properties are remarkably improved. The addition ratio of such protease cannot be specified because it varies depending on the enzyme preparation and reaction conditions, but is preferably 0.0001 to 5% by weight with respect to the whole emulsion. If the amount is less than 0.0001% by weight, the enzymatic reaction does not proceed sufficiently, and therefore the sufficient modification effect cannot be observed unless the reaction time is extremely long. On the other hand, if it exceeds 5% by weight, the viscosity of the emulsion remarkably increases due to emulsion breakage, which is not preferable. The degree of reaction can be known by performing protein analysis by SDS-PAGE electrophoresis or reverse phase liquid chromatography. More specifically, the protein in the cream is extracted with a solubilizing agent such as urea, and the oil and fat components are removed by centrifugation, and then SDS-PA.
Separation and analysis by GE electrophoresis or reverse phase liquid chromatography, and the ratio of the peak amount appearing at the elution position of undegraded protein to the integrated amount of all eluted peaks is 100%.
The value subtracted from can be known as the decomposition rate. Also,
The enzyme can be easily inactivated in the high temperature sterilization step, and thus does not necessarily require any other inactivation treatment step. Further, in the present invention, the effect of improving the shape retention is recognized when the decomposition treatment is performed so that the decomposition rate of the protein is 10% or more, but 50% is required to obtain a sufficient effect for improving the shape retention.
The above decomposition rate, more preferably 80% or more, is desirable.

Next, the glycerin monofatty acid ester (hereinafter sometimes simply referred to as monoglyceride) and the glycerin difatty acid ester (hereinafter sometimes simply referred to as diglyceride) used in the present invention will be described. In the present invention, the ratio of monoglyceride and diglyceride used is preferably 2: 1 to 19: 1 (weight basis), and the total content thereof is 1 to 40% by weight based on the oil phase. preferable. Also, monoglyceride
The constituent fatty acid residue is a saturated fatty acid residue having 12 to 22 carbon atoms. Examples of the saturated fatty acid residue having 12 to 22 carbon atoms include palmitic acid, stearic acid, arachidic acid and behenic acid residues. Among them, saturated fatty acid residues having 16 to 18 carbon atoms, that is, palmitic acid, stearic acid residues and the like are preferable, and it is more preferable that they account for 30 to 90% by weight of all fatty acid residues. The constituent fatty acid residue of the diglyceride is a saturated fatty acid residue having 12 to 22 carbon atoms. Examples of the saturated fatty acid residue having 12 to 22 carbon atoms include those similar to the above case. Among them, saturated fatty acid residues having 20 to 22 carbon atoms, that is, arachidic acid, behenic acid residues and the like are preferable, and it is more preferable that they account for 10 to 70% by weight of all fatty acid residues. This diglyceride includes, for example, one or two kinds of fats and oils selected from fats and oils having a saturated fatty acid having 16 to 22 carbon atoms as a main component (for example, hardened oil of palm oil or helsin rapeseed oil) and glycerin It can be obtained by exchanging with an ester in the presence of a hydroxide of an earth metal or an alkaline earth metal, or by an esterification reaction of a saturated fatty acid mixture having 16 to 22 carbon atoms with a high oil content and glycerin. . The excess monoglyceride produced in the reaction can be removed by using a molecular distillation method or a separation means such as chromatography.
In addition, in the preparation of the saturated diglyceride, it is preferable to carry out the reaction under mild conditions using an enzyme such as a 1,3-position selective lipase because the glycerin difatty acid ester of the obtained fatty acid has a good flavor. It should be noted that separation of only saturated diglyceride is not industrially advantageous, and thus it may be used as a mixture with monoglyceride and / or triglyceride.

The foamable oil-in-water emulsion of the present invention can be produced by a conventional method using the above components. For example, an edible oil and fat and an oily component containing a monoester and a diester (oil phase) and an aqueous component containing water, protein, sugar and an emulsifier (water phase) are heated to appropriate temperatures, respectively, and then both are mixed. Pre-emulsification, homogenization, sterilization,
It can be produced by carrying out the usual processes of rehomogenization, cooling, and aging. When the emulsion is prepared, the oily component and the aqueous component may be mixed in separate systems as described above, and then the two may be mixed, or one system may be prepared from the beginning. The emulsion is adjusted so that the oil phase component is 3 to 50% by weight (preferably 10 to 40% by weight) and the aqueous phase component is 50 to 97% by weight (preferably 60 to 90% by weight). The foamable oil-in-water emulsion of the present invention thus obtained has a viscosity of 200 to 4000 at 5 ° C., considering its whipping characteristics and the like.
cp (preferably 200 to 2000 cp) is preferably adjusted.

[0011]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. However, these are examples and do not limit the present invention. That is, it goes without saying that the order of addition of the additives is not limited to the following examples, and the addition timing of the protease is not particularly limited except that it is added to the oil-in-water emulsion. In the examples, “parts” means “parts by weight”. Example 1 (Preparation of Effervescent Oil-in-Water Emulsion) [Compounding] Palm kernel hydrogenated oil 15 parts Soybean hydrogenated oil 10 parts Syrup 20 parts Glucose 10 parts Maltose 15 parts Skim milk powder 5 parts Soybean lecithin 0.3 parts Oleic acid monoglyceride 0.1 parts Sucrose fatty acid ester (HLB16) 0.2 parts Sodium hexametaphosphate 0.1 parts Water 24.3 parts ────────────────────────── Total 100.0 parts [Operation] Palm 0.3 part of soybean lecithin and 0.1 part of oleic acid monoglyceride were dissolved in 15 parts of hardened kernel oil and 10 parts of hardened soybean oil to prepare an oil phase part. 20 parts starch syrup in water, 10 parts glucose,
15 parts maltose, 5 parts skim milk powder, 0.2 parts sucrose fatty acid ester (HLB16) and sodium hexametaphosphate
0.1 part was melt | dissolved and it was set as the water phase part. The oil phase part was added to the water phase part, and the mixture was pre-emulsified with a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at 60 ° C for 10 minutes, and then homogenized under the condition of 150 kg / cm ² . To this oil-in-water emulsion, 0.01 part of protease (metalloprotease derived from Bacillus bacterium, Kao Corporation)
) Was added and reacted at room temperature for 30 minutes. Immediately after the enzyme-treated emulsion was sterilized in a sterilizer at 145 ° C for 5 seconds, it was homogenized in 2 stages under the conditions of 60 kg / cm ² and kept below 8 ° C. Aged in the refrigerator for 12 hours or longer to obtain an oil-in-water emulsion. Example 2 In Example 1, the protease was added to the pre-emulsified oil-in-water emulsion and reacted at 65 ° C. for 5 minutes,
Homogenization, sterilization, two-stage homogenization were performed, and aging was performed in the same manner to obtain an oil-in-water emulsion. Example 3 The same procedure as in Example 1 was repeated except that the protease was not added until the two-step homogenization. Then, the emulsion after the two-step homogenization was cooled to 5 ° C, and protease was added to the homogenized solution at 5 ° C.
After reacting for a time, it was sterilized in a sterilizer at 145 ° C. for 5 seconds and then aged in the same manner to obtain an oil-in-water emulsion. Comparative Example 1 An oil-in-water emulsion was obtained in the same manner as in Example 1 except that the enzyme treatment with protease was not performed. Comparative Example 2 In Example 1, protease was added to the aqueous phase portion and reacted at room temperature for 30 minutes, and then the oil phase portion was pre-emulsified in the same manner as in Example 1, and thereafter the same operation as in Example 1 was performed. An oil-in-water emulsion was obtained. Comparative Example 3 After inactivating the enzyme by heating the aqueous phase portion treated with the enzyme with protease in the same manner as in Comparative Example 2 at 80 ° C. for 10 minutes,
An oil-in-water emulsion was obtained in the same manner as in Example 1 except that the oil phase was added and the protease was not added thereafter. Comparative Example 4 In Comparative Example 1, the composition of the oil phase part was changed to palm kernel hardened oil 6
Parts, 9 parts of hardened palm kernel oil, and 10 parts of hardened soybean oil were used to obtain an oil-in-water emulsion in the same manner as above.

[Evaluation] The oil-in-water emulsion thus obtained was whipped with a mixer (manufactured by Hobard Canada) to prepare a whipped cream, and (1)
The shape retention, (2) water separation amount, (3) melting in mouth, and (4) texture were evaluated. (1) Shape retention The heat-resistant shape retention was evaluated using the obtained whipped cream.
After being stored for 48 hours in an atmosphere of ° C, the shape change was evaluated in three grades of good, slightly broken, and broken (almost no shape remained). (2) Water separation amount The amount of water separated per cream is shown by weight%. The following organoleptic evaluation of melting in mouth and texture was performed by a comparative test by 20 panelists trained with the cream of Comparative Example 1 as a control. The evaluation criteria are as follows. (3) Melting in the mouth Compared to the cream of Comparative Example 1, the results showed the most support in the three-grade evaluations of good, equivalent, and poor. (4) Texture As compared with the cream of Comparative Example 1, the results showed the most support in the three-level evaluation of good, equivalent, and poor. The results are shown in Table 1 below.

[0013]

[Table 1]

From the results shown in Table 1 above, the cream comprising the oil-in-water emulsion of the present invention in which the protein is decomposed by protease in the emulsified state can be obtained by the conventionally known reaction in the aqueous phase. It has better shape retention and water separation resistance than the one with protein hydrolyzate added, and more flavor and flavor than the one with high melting point oil (Comparative Example 4).
The texture was excellent.

Next, examples in which monoglyceride and diglyceride are used in combination are shown. The monoglyceride and diglyceride used in the following examples have the following compositions. Sample 1 Sample 2 Monoglyceride Diglyceride MG 90.9 0.7 DG 5.9 90.3 TG 3.2 9.0 Myristic acid (C ₁₄ ) 2.4 ── Palmitic acid (C ₁₆ ) 27.7 1.6 Stearic acid (C ₁₈ ) 66.2 0.9 Arachidic acid (C ₂₀ ) ── 1.3 Behen acid (C ₂₂₎ 1.7 89.2 Others 2.0 7.0 (the composition of the foamable oil-in-water emulsion) (oil phase) palm kernel oil hydrogenated oil (iodine value = 2) 22.0 sample 1 2.0 sample 2 1.0 soybean lecithin (a commercial soybean lecithin ) 0.3 (water phase) glucose 20.0 maltose 20.0 sodium caseinate 0.5 skim milk powder 5.0 xanthan gum 0.1 sodium hexametaphosphate 0.1 sucrose fatty acid ester (HLB11) 0.5 water 28.5 total 100.0 (parts) Example 4 The oil phase (oily liquid) of the above composition , And an aqueous phase (aqueous liquid) were mixed, and pre-emulsification was performed with a homomixer (manufactured by Tokushu Kika Kogyo) at 65 ° C. for 10 minutes. The obtained preliminary emulsion was homogenized (30 kg / cm ² ) with a homogenizer at 55 ° C. To this oil-in-water emulsion, 0.01 part of protease (metal protease derived from Bacillus genus: manufactured by Kao Corporation)
The resulting emulsion was immediately added to a UHT sterilizer (145 ° C, 2 seconds, Iwai Machinery Co., Ltd.)
), And then aseptically re-homogenize with a homogenizer at 70 ° C (30-45 kg /
cm ² ). The obtained emulsion was cooled to 15 ° C., filled and then aged overnight to prepare a foamable oil-in-water emulsion according to the present invention. Example 5 In Example 4, after pre-emulsification and homogenization treatment, protease was added and reacted at 55 ° C. for 5 minutes, followed by sterilization and rehomogenization, and aging in the same manner to give an oil-in-water emulsion. Got Example 6 In Example 4, after pre-emulsification and homogenization treatment, protease was added and reacted at 55 ° C. for 300 minutes, followed by sterilization and rehomogenization, and aging in the same manner to obtain an oil-in-water emulsion. Got Example 7 In Example 4, after pre-emulsification and homogenization treatment, cooling was performed to 20 ° C., protease was added, and the temperature was increased to 20 ° C.
After reacting for 60 minutes, the mixture was sterilized and rehomogenized, and similarly aged to obtain an oil-in-water emulsion. Example 8 In Example 4, after pre-emulsification and homogenization treatment, the mixture was cooled to 5 ° C, protease was added, and the mixture was added to 5 ° C.
After reacting for 60 minutes, the mixture was sterilized and rehomogenized, and similarly aged to obtain an oil-in-water emulsion. Comparative Example 5 An oil-in-water emulsion was obtained in the same manner as in Example 4, except that the enzyme treatment with protease was not performed. Comparative Example 6 In Example 4, protease was added to the aqueous phase part,
After reacting at 60 ° C. for 60 minutes, the same operation as in Example 4 was performed to obtain an oil-in-water emulsion. Comparative Example 7 In Example 4, protease was added to the aqueous phase part,
After reacting at 60 ° C. for 60 minutes, heat treatment was performed at 80 ° C. for 10 minutes to inactivate the enzyme, and then the same operation as in Example 4 was performed to obtain an oil-in-water emulsion.

(Evaluation) The thus obtained oil-in-water emulsion was whipped to prepare a whipped cream, and (1) shape retention, (2) water release amount, (3) mouth-feeling and texture, (4) Bitterness and (5) acid resistance were evaluated. (1) Shape retention The heat resistance of the whipped cream was evaluated at 30 ° C.
After storing for 5 days in the atmosphere, the shape change and the water separation state were observed according to the following criteria. ◯: No change in shape and no syneresis. Δ: Change in shape and part of water separation are observed, but this is within the allowable range. X: The entire shape is broken and water separation is considerably observed. (2) Amount of water separation The amount of water separated per cream is shown by weight%. (3) Melting sensation in mouth, texture Sense of melting in mouth and texture were measured by sensory test by a specialized panelist on the obtained whipped cream. ○: Melting in the mouth feels very good. Δ: Neither can be said. X: Melting in the mouth feels very bad. (4) Bitterness The bitterness was determined by a sensory test by a specialized panelist on the obtained whipped cream. ○: No bitterness is felt. Δ: Neither can be said. X: A bitterness is felt. (5) Acid resistance Citric acid was added to the cream to adjust the pH of the cream to 3.0. This was whipped and the state was observed. Good: Workability is better than that without addition of citric acid. Δ: The workability is not so rough as compared with the case where no citric acid is added. X: Aggregates immediately when citric acid is added.

[0017]

[Table 2]

From the results shown in Table 2 above, the cream of the oil-in-water emulsion of the present invention, which is not treated with the enzyme, cannot maintain the shape retention sufficiently (Comparative Example 5). Next, it had good shape retention and water separation resistance as compared with those obtained by adding protein hydrolysis obtained by the conventional reaction in an aqueous phase (Comparative Examples 6 and 7).

[0019]

EFFECTS OF THE INVENTION According to the present invention, it is possible to store foods at room temperature without adding a high melting point oil and fat, and it is possible to develop a food product using a foaming oil-in-water emulsion having a mouthfeel and a good texture and flavor. Further, a foamable oil-in-water emulsion having further acid resistance can be provided.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masanobu Uchikoshi 20 Kasumi-cho, Kashima-gun, Ibaraki Prefecture, Kago Stock Company, Research Institute (72) Inventor Kumiko Kinoshita 20-Kashisu-cho, Kashima-gun, Kazuma-shi, Tokashiba Corporation Kao Stock Company, Research Institute ( 72) Inventor Nao Takeshita 20 Kao Stock Company Research Institute, Kamisu-cho, Kashima-gun, Ibaraki Prefecture (72) Inventor Ken Goto 20 Tohashishiba Toshiba Corporation, Kasu-cho, Kashima-gun, Ibaraki Prefecture Kao Stock Company Research Center

Claims (10)

[Claims] 1. An oil-in-water emulsion, characterized in that in an emulsion obtained by emulsifying an oil phase and an aqueous phase, a protein component complexed with the oil phase or adsorbed to the oil phase is decomposed with a protease. Manufacturing method. 2. The method for producing an oil-in-water emulsion according to claim 1, wherein the oil-in-water emulsion is a foaming oil-in-water emulsion. 3. An oil-in-water emulsion obtained by the method according to claim 1. 4. The oil-in-water emulsion according to claim 3, wherein the oil-in-water emulsion is a foaming oil-in-water emulsion for whipped cream. 5. An emulsion obtained by emulsifying an oil phase containing a glycerin monofatty acid ester and a glycerin difatty acid ester and an aqueous phase, wherein a protein component complexed with the oil phase or adsorbed to the oil phase is treated with a protease. A method for producing an oil-in-water emulsion, which comprises decomposing. 6. The ratio of glycerin monofatty acid ester and glycerin difatty acid ester is 2: 1 to 19: 1 (weight basis), and the total content thereof is 1 to 40% by weight based on the oil phase. 5. The method for producing the oil-in-water emulsion according to 5. 7. A fatty acid residue constituting glycerin monofatty acid ester and glycerin difatty acid ester has 12 carbon atoms.
The method for producing an oil-in-water emulsion according to claim 5 or 6, wherein the saturated fatty acid is -22. 8. The fatty acid residue constituting the glycerin monofatty acid ester is a fatty acid having 16 to 18 carbon atoms, and the fatty acid residue constituting the glycerin difatty acid ester is 20 to 20 carbon atoms.
The method for producing an oil-in-water emulsion according to claim 7, wherein the fatty acid is 22. 9. An oil-in-water emulsion obtained by the method according to claim 5. 10. The oil-in-water emulsion according to claim 9, wherein the oil-in-water emulsion is a foaming oil-in-water emulsion for whipped cream.