JP4674961B2 - Oil-in-water emulsion - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oil-in-water emulsion containing a milk component. Specifically, the present invention relates to an oil-in-water emulsion containing a polyglycerin fatty acid ester having a specific cloud point and excellent in heat stability and emulsification stability after sterilization.
[0002]
[Prior art]
Creams containing dairy ingredients are used for coffee or foamed and used as a decoration for cakes and the like. Conventionally, so-called natural fresh cream obtained by concentrating fat by centrifuging milk has been used as creams containing milk components. Natural raw claims form stable oil-in-water emulsions with milk proteins and lipids. However, fresh cream is expensive and its quality varies due to seasonal variations, making it difficult to supply a stable product. For this reason, synthetic creams obtained by mixing edible oils and fats, non-fat milk solids, emulsifiers, stabilizers and the like and emulsifying them have been developed in recent years.
[0003]
The properties required for these creams are that the quality is constant, that it is stable for cooling after high-temperature sterilization, and that no thickening or solidification occurs due to temperature changes and vibration during storage or transfer. Can be mentioned.
Creams are classified into those for various uses depending on the content of oil or milk fat, but the functions required in this case are different for each cream. For example, in the case of coffee cream, it is important that the dispersibility of the cream when it is put into coffee, that feathering and oil-off are suppressed, and that the whitener property is good. In addition, the whipped cream is required to have an appropriate overrun at the time of foaming, that the foam is stable, that it is easy to squeeze, has good shape-retaining properties, and has a good taste and mouthfeel.
[0004]
However, in order for the properties according to the various creams described above to be expressed, first, the emulsion stability of the stock solution is required. If the emulsion stability of the stock solution is not good, the intended function is achieved. Hateful. In the case of whipped cream in particular, the fat content is high, so that thickening easily occurs during storage of the stock solution.
[0005]
[Problems to be solved by the invention]
Among such creams, whipped cream having a high fat content has been studied to add a polyglycerol fatty acid ester as an emulsifier (JP-A-2-128644, JP-A-5-23126). Gazette, JP-A-10-84900, etc.). However, in either case, the heat resistance is weak, and the physical properties are not satisfactory, for example, the emulsification is broken during storage and water separation occurs.
[0006]
Therefore, development of the technique which improves the emulsification stability of the cream containing a milk component has been desired.
[0007]
[Means for Solving the Problems]
As a result of various investigations in view of the above circumstances, the present inventor has incorporated a polyglycerin fatty acid ester having a specific cloud point into an oil-in-water emulsion prepared using edible fats and oils, thereby aggregating a milk emulsion. It has been found that the oil-in-water emulsification state is maintained even after sterilization, and the present invention has been reached.
[0008]
That is, the gist of the present invention, the oil fat, with a oil-in-water emulsion consisting of an aqueous phase containing a milk component, cloud point measured in 1% strength by weight in a 20% aqueous solution of sodium chloride is 90 ° C. or higher It exists in the oil-in-water emulsion characterized by containing a certain polyglyceryl fatty acid ester, and content of fats and oils in an oil-in-water emulsion is 20 to 60 weight%.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The oil-in-water emulsion in the present invention comprises an oil and fat, a milk component, water, and a polyglycerin fatty acid ester having a specific cloud point as essential components, and further comprises other components as necessary.
[0010]
The fats and oils used in the present invention are not particularly limited as long as they are edible. For example, vegetable fats and oils such as soybean oil, coconut oil, palm oil, rapeseed oil, corn oil, olive oil, cottonseed oil, safflower oil, corn oil and the like And animal fats such as milk fat, beef tallow, pork fat and fish oil, and processed fats and oils obtained by curing, fractionating and transesterifying these fats. These fats and oils can be used alone or in combination. The amount of fats and oils in the oil-in-water emulsion is 20 to 60% by weight, preferably 25 to 45% by weight. If the amount of fat is less than 20% by weight, sufficient shape retention cannot be obtained for whipped cream, or the viscosity of coffee cream decreases. On the other hand, if it exceeds 60% by weight, the oil-in-water emulsion tends to increase in viscosity, so that good emulsification cannot be obtained, which is not preferable.
[0011]
As the milk component used in the present invention, skim milk, skim milk powder, whole milk powder, casein, casein sodium and the like are usually used, but not limited thereto, and any milk protein can be used. . The amount of the milk component in the oil-in-water emulsion is usually 0.4 to 5.0% by weight.
The polyglycerin fatty acid ester used in the present invention has a cloud point of 90 ° C. or higher measured at a concentration of 1% by weight in a 20% aqueous sodium chloride solution. The polyglycerol fatty acid ester is a mixture of an ester obtained by reaction of polyglycerol and a fatty acid and unreacted polyglycerol. The amount of residual polyglycerol in the polyglycerol fatty acid ester is preferably 70% by weight or less. In order to obtain a polyglycerin fatty acid ester having such a cloud point range, the ratio of fatty acid to polyglycerin is reduced and the amount of alkali catalyst is reduced (for example, K ₂ CO ₃ , KOH, Na ₂ CO ₃ , NaOH, etc. 5 × 10 ^{−7 to} 0.1 mol times with respect to polyglycerin), and a method of increasing the latter half temperature in a two-step reaction, for example, after an esterification reaction at a reaction temperature of 180 to 260 ° C. Further, a method of reacting for 1 to 4 hours by raising the reaction temperature by 10 to 50 ° C. can be used. (See JP-A-7-145104).
[0012]
As a cloud point measurement method, it is usually necessary to measure after dissolving a polyglycerol fatty acid ester in 1 to 30% sodium chloride or sodium sulfate aqueous solution, and the conditions differ depending on the solubility of the target sample, The measurement method of the present invention will be described. In the case of the present invention, first, polyglycerin fatty acid ester is dispersed in a 20 wt% sodium chloride aqueous solution so as to be 1 wt%, and stirred while heating to obtain a uniform aqueous solution. Then, the obtained polyglycerol fatty acid ester homogeneous aqueous solution is shaken and allowed to stand at an arbitrary temperature of 0 ° C. or more and 100 ° C. or less in increments of 2 to 5 ° C. to separate the polyglycerol fatty acid ester as an oil or gel. Measure the temperature at which the aqueous solution becomes heterogeneous. The temperature at which this non-uniform state occurs is called the “cloud point”, and the temperature is determined in the present invention. If it is less than 0 ° C., it is below the melting point of ice, and if it exceeds 100 ° C., it becomes more than the boiling point of water. The cloud point of 90 ° C. or higher includes a case where a non-uniform aqueous solution is obtained at 90 ° C. or higher and a case where the cloud point does not become a non-uniform aqueous solution even when the temperature exceeds 100 ° C. The cloud point is preferably 100 ° C. or higher. A cloud point of 100 ° C. or higher means a case where a non-uniform aqueous solution is not obtained even at 100 ° C.
[0013]
Specific examples of the fatty acid constituting the polyglycerin fatty acid ester include saturated or unsaturated fatty acids having 14 to 22 carbon atoms such as myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, etc. What has a main component is preferable. As the constituent fatty acid, fatty acids having the same carbon number may be used, or a mixture of a plurality of fatty acids having different carbon numbers may be used. As a polymerization degree of the polyglycerol which comprises polyglycerol fatty acid ester, an average polymerization degree is 2-20 normally, Preferably an average polymerization degree is 4-12. The content of polyglycerin fatty acid ester having a cloud point of 90 ° C. or higher measured at 1% by weight in a 20% aqueous sodium chloride solution in an oil-in-water emulsion is usually 0.1 to 1.0% by weight.
[0014]
The oil-in-water emulsion of the present invention usually uses at least one other emulsifier in combination. The emulsifier is not particularly limited as long as it is usually used in the production of cream, but is preferably easily dispersible in oil, for example, lecithin, glycerin fatty acid fatty acid ester, sorbitan fatty acid ester, polysorbate, organic acid monoglyceride, propylene Examples include glycol fatty acid esters, sucrose fatty acid esters having an HLB of 0 to less than 5, and polyglycerin fatty acid esters having an HLB of 8 or less.
[0015]
The oil-in-water emulsion of the present invention can contain other additives other than those described above, for example, salts, stabilizers, flavoring agents, and the like as necessary. As the salts, phosphate, citrate and the like are used. As the stabilizer, cellulose, carrageenan, locust bean gum, xanthan gum, guar gum and the like are used. The amount of the stabilizer is preferably 0.1 to 1.0% by weight, and more preferably 0.2 to 0.7% by weight. If the amount of the stabilizer is less than 0.1% by weight, an appropriate viscosity may not be obtained. Conversely, if the amount exceeds 1.0% by weight, the oil-in-water emulsion increases in viscosity, which is not preferable. Arbitrary things can be used as a flavoring agent. Examples include vanilla essence, milk flavor, butter flavor and the like.
[0016]
The oil-in-water emulsion of the present invention is usually produced by the following method.
First, a milk component, a polyglycerin fatty acid ester having a cloud point of 90 ° C. or higher measured at 1% by weight in a 20% sodium chloride aqueous solution, and other water-soluble additives are dissolved in water to prepare an aqueous phase. The content of the milk component in the aqueous phase is usually 0.4 to 5.0% by weight, preferably 0.5 to 3.0% by weight. If the amount of the milk component is less than 0.4% by weight, the flavor as a cream is not sufficient, and if it exceeds 5.0% by weight, the oil-in-water emulsion increases in viscosity, which is not preferable. The content of the polyglycerin fatty acid ester having a cloud point of 90 ° C. or higher measured at 1% by weight in a 20% aqueous sodium chloride solution in the aqueous phase is usually 0.1 to 1.0% by weight.
[0017]
Moreover, the emulsifier which is easy to disperse | distribute to oil, and another oil-soluble additive are melt | dissolved in fats and oils at 60-70 degreeC, and an oil phase is prepared. The content of the emulsifier in the oil phase is usually 0.1 to 1.5% by weight.
Next, the prepared oil phase and aqueous phase are mixed at 60 to 70 ° C., pre-emulsified, and homogenized at 60 to 70 ° C. using a homogenizer, and then cooled.
The ratio of the oil phase to the aqueous phase is usually 1/4 to 3/2 (weight ratio).
[0018]
The oil-in-water emulsion thus prepared is further sterilized by heating, but it is preferable to perform UHT sterilization from the viewpoint of maintaining the flavor and preventing browning. The UHT sterilization used in the present invention is an ultra-high temperature sterilization corresponding to a sterilization temperature of 130 to 150 ° C. and a sterilization time of 5 to 30 seconds. UHT sterilization is a known method such as a direct injection method such as a steam injection method in which steam is directly blown into the cream, a steam infusion method in which the cream is injected into steam, and an indirect heating method using a surface heat exchanger such as a plate or tube. Can be done.
[0019]
The oil-in-water emulsion of the present invention is usually used as a dairy product. Examples of dairy products include ice cream, custard cream, whipped cream, coffee cream, and clotted cream, but whipped cream is preferred. The oil-in-water emulsion of the present invention does not include milk drinks.
[0020]
【Example】
EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In the examples, unless otherwise specified,% by weight is% by weight relative to the oil-in-water emulsion.
[Production example]
188 g (0.27 mol) of decaglycerin (average degree of polymerization 9.15, average molecular weight 695, hydroxyl value 900) and myristic acid (purity 99%, average molecular weight 228) 62 g (0.27 mol) with a heating jacket The reaction vessel was charged, 0.025 g of 25% sodium hydroxide (based on the total amount of raw materials: 0.0025 wt%) was added, the temperature was raised to 240 ° C. in a nitrogen stream and reacted for 3 hours, and then at 260 ° C. for 4 hours. The reaction was performed to obtain 234 g of decaglycerin myristic acid ester.
Example 1
608.4 g (56.84% by weight) of water at 60 ° C. 90 g (9.00% by weight) sugar, 30 g (3.00% by weight) skim milk powder, 1 g (0.10% by weight) guar gum, decaglycerin myristic acid 3 g (0.30 wt%) of an ester (cloud point of 100 ° C. or higher) and 1 g (0.10 wt%) of sodium hexametaphosphate were added and dissolved to obtain an aqueous phase portion. Separately, 300 g (30.00 wt%) of partially hydrogenated soybean oil heated to 70 ° C., 0.6 g (0.06 wt%) of lecithin, sucrose stearate (trade name Ryoto Sugar Ester, Mitsubishi Chemical Foods Co., Ltd.) S-270, HLB2) 3 g (0.30 wt%) and sucrose erucic acid ester (Mitsubishi Chemical Foods Co., Ltd. trade name Ryoto Sugar Ester ER-290, HLB2) 3 g (0.30 wt%) were dissolved. Oil phase part. The aqueous phase was put into this, and pre-emulsified with a propeller stirrer at 70 ° C. for 15 minutes. This pre-emulsified liquid was homogenized by pressurization with a primary pressure of 150 kg / cm 2 and a secondary pressure of 50 kg / cm 2 using a homogenizer (manufactured by APV Gaulin). Next, the obtained oil-in-water emulsion was sterilized at 130 ° C., immediately cooled to 10 ° C. or lower in ice water, and aged overnight in a refrigerator to obtain a whipped cream. About the obtained cream, as a result of evaluating the state of the cream by particle size measurement (HOLIBA-LA500) and visual observation, the particle size distribution is a sharp single peak, and the state in which the cream is thickened is not observed. The emulsified state was good.
Comparative Example 1
Instead of decaglycerin myristic acid ester (cloud point of 100 ° C. or higher), decaglycerin stearate ester (Mitsubishi Chemical Foods Co., Ltd. trade name Ryoto polyglycerester S-28D, cloud point of 50 ° C. or lower) 3 g (0.30% by weight) ) Was added and evaluated in the same manner as in Example except that was added to the aqueous phase. The cream after aging started to thicken and solidify and had a wide particle size distribution.
[0021]
【The invention's effect】
The oil-in-water emulsion of the present invention does not increase in viscosity or solidify even when sterilized, and is excellent in heat resistance and emulsion stability.

Claims (5)

  An oil-in-water emulsion comprising an oil and fat and an aqueous phase containing a milk component, comprising a polyglycerin fatty acid ester having a cloud point of 90 ° C. or higher measured at a concentration of 1% by weight in a 20% aqueous sodium chloride solution, And oil-in-water type emulsion characterized by content of fats and oils in oil-in-water type emulsion being 20 to 60 weight%. 2. The oil-in-water emulsion according to claim 1, wherein the polyglycerin constituting the polyglycerin fatty acid ester has an average degree of polymerization of 4 to 12 and an amount of residual polyglycerin is 70% by weight or less. The oil-in-water emulsion according to claim 1 or 2 , wherein the constituent fatty acid of the polyglycerin fatty acid ester is one or more fatty acids selected from saturated or unsaturated fatty acids having 14 to 22 carbon atoms. . 4. The oil-in-water emulsion according to any one of claims 1 to 3 , wherein the constituent fatty acid of the polyglycerol fatty acid ester is myristic acid. The oil-in-water emulsion according to any one of claims 1 to 4 , wherein the oil-in-water emulsion is a dairy product.