JP4360189B2 - Milk beverage containing sucrose fatty acid ester and polyglycerin fatty acid ester - Google Patents

Description

  The present invention relates to a milk beverage excellent in emulsion stability containing a sucrose fatty acid ester and a polyglycerin fatty acid ester.

  In recent years, many coffee beverages that emphasize the original taste of coffee beans reflecting consumer preferences have been manufactured and sold. However, in coffee beverages containing milk components, separation of milk components during storage has been more than conventional. It was a problem. In coffee containing a dairy component, the dairy component floats at the top along with long-term storage. This phenomenon is well known in milk coffee and the like, but the milk components that have floated with the passage of time aggregate and coalesce into a so-called neck ring state. In this case, the redispersibility deteriorates, and the lump of milk components floats on the upper part even after redispersion.

  In recent years, in particular, beverages containing PET bottles have become widespread instead of canned beverages, so emulsification stability of milk components has become more important. This is because the PET bottle is a transparent container, so that the consumer can see the appearance of coffee, and when separation of milk components occurs in the PET bottle beverage, it gives the consumer an unpleasant impression and the commercial value decreases. Or it may lead to complaints.

  In order to produce milk coffee that maintains good emulsification stability and flavor even when stored for long periods of time in a vending machine, in order to produce milk coffee, the constituent fatty acid is HLB10 or higher with a high monoester content mainly composed of palmitic acid A method of adding a sucrose fatty acid ester in combination with a sucrose fatty acid ester whose constituent fatty acid is mainly stearic acid and less than HLB 10 is known (Patent Document 1).

  In order to maintain long-term emulsion stability in PET bottled milk beverages, the constituent fatty acids in sucrose fatty acid esters of HLB 10 or higher and a 20% by weight sodium chloride aqueous solution having a high monoester content mainly composed of palmitic acid A method is known in which a polyglycerin fatty acid ester having a cloud point measured at a concentration of 1% by weight of 90 ° C. or higher is added in combination (Patent Document 2).

Recently, the amount of roasted coffee beans is large, and PET bottled beverages using beans with various roasting degrees are increasing. However, coffee beverages containing deeply roasted coffee bean extracts and milk components are not milky. It is known that the component floats faster.
Japanese Patent Laid-Open No. 7-289164 JP 2000-333599 A

However, in the conventional technology, a milk coffee with a large amount of roasted coffee beans and deep roasting has not been sufficiently satisfactory in emulsion stability.
Therefore, even when the amount of roasted coffee beans is large or when deeply roasted coffee beans are used, the development of a coffee beverage that suppresses the floating of milk components and does not agglomerate even when stored for a long period of time is desired. It was.

Thus, as a result of intensive studies, the present inventors have found that when a specific emulsion stabilizer is added to a milk beverage, the floating of milk components is suppressed and the emulsion stability is improved, and the present invention has been achieved. did. That is, the gist of the present invention is a milk beverage containing a sucrose fatty acid ester of HLB10 or higher, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of less than HLB10, and comprising a polyglycerin fatty acid ester / HLB10 or higher sucrose fatty acid ester Exists in a milk beverage having a weight ratio of 0.5 to 1/1.

Another gist of the present invention is an emulsion stabilizer for milk beverages containing a sucrose fatty acid ester of HLB10 or higher, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of less than HLB10 , wherein the polyglycerin fatty acid ester / HLB10 or higher It exists in the emulsion stabilizer for milk drinks whose weight ratio of a sucrose fatty acid ester is the range of 0.5-1 / 1 .

  The milk beverage of the present invention can suppress the floating of milk components after heat sterilization by adding a specific emulsion stabilizer, and also has good emulsion stability after long-term storage.

Hereinafter, the present invention will be described in detail.
The milk beverage of the present invention contains sucrose fatty acid ester of HLB10 or higher, polyglycerin fatty acid ester, and sucrose fatty acid ester of less than HLB10, and the weight of sucrose fatty acid ester of polyglycerin fatty acid ester / HLB10 or higher. The ratio is in the range of 0.5 to 1/1 .
[Sucrose fatty acid ester of HLB 10 or more]
As a sucrose fatty acid ester having an HLB of 10 or more, the monoester content is usually 50% by weight or more, and the constituent fatty acids are saturated with 14 to 22 carbon atoms such as myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid or the like. Examples include unsaturated fatty acids. The constituent fatty acid is preferably a fatty acid having 16 to 18 carbon atoms, and is preferably a saturated fatty acid. Among them, from the viewpoints of emulsion stability and antibacterial properties, 70% by weight or more is preferably palmitic acid or stearic acid, the monoester content is 70% by weight or more, and the constituent fatty acid is 80% by weight or more palmitic acid. Certain sucrose fatty acid esters are most preferred. HLB is preferably 15 or more, and more preferably 16 or more. HLB is usually 22 or less, preferably 18 or less. The amount of sucrose fatty acid ester of HLB 10 or more added to the milk beverage is preferably 0.03 to 0.1% by weight.
[Polyglycerin fatty acid ester]
Specific examples of fatty acids 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 and the like. Among these, fatty acids having 14 to 18 carbon atoms are preferable, and saturated fatty acids are preferable. In particular, those containing myristic acid as the main component are preferred. As a polymerization degree of the polyglycerol which comprises polyglycerol fatty acid ester, an average degree of polymerization is 2-20 normally, Preferably an average degree of polymerization is 4-12.

The polyglycerin fatty acid ester preferably has a cloud point range measured at 1% by weight in a 20% by weight sodium chloride aqueous solution of 80 or more, and in particular, a cloud point range measured at 1% by weight in a 20% by weight sodium chloride aqueous solution. A highly hydrophilic polyglycerin fatty acid ester having a temperature of 90 ° C. or higher is most preferable.
The polyglycerin fatty acid ester having such a cloud point range is usually obtained by reducing the charge ratio of fatty acid to polyglycerin and reacting at a temperature of 180 to 260 in the presence of an alkali catalyst. In general, the feed ratio of the fatty acid is 2 mol times or less with respect to the polyglycerol fatty acid ester, and the alkali metal catalyst is K ₂ CO ₃ , KOH, Na ₂ CO ₃ , NaOH, etc. 5 × 10 ^{−7 with} respect to the polyglycerol. Use ~ 1 mole times.

Polyglycerin fatty acid esters having a cloud point range of 90 ° C. or higher measured at 1% by weight in a 20% by weight sodium chloride aqueous solution usually reduce the amount of alkali catalyst (for example, K ₂ CO ₃ , KOH, Na ₂ CO ₃ , A method of increasing the latter half of the temperature in a two-stage reaction, such as NaOH, using 5 × 10 ^{−7 to} 0.1 mol times relative to polyglycerol, for example, after the esterification reaction at a reaction temperature of 180 to 260, further reaction A method of raising the temperature by 10 to 50 ° C. and reacting for 1 to 4 hours can be used (see JP-A-7-145104).

Various chemical analysis methods have been used so far for the analysis of polyglycerin fatty acid esters (hereinafter sometimes abbreviated as “PoGE”). For example, an acid value, a saponification value, and a hydroxyl value are often used to grasp the degree of esterification and the amount of residual fatty acid, and evaluation methods such as analysis of ash to determine the amount of soap or residual catalyst have also been used. It was.
However, polyglycerin (hereinafter sometimes abbreviated as “PoG”), which is a raw material for PoGE, is a polycondensate of glycerin and is difficult to purify. As well as branched polymers and cyclic polymers. Therefore, PoGE which is an ester form thereof is a composition containing PoGE having various degrees of esterification with different PoG skeletons and unreacted PoG. In addition, PoGE contains excessive amounts of soap as a by-product produced by the reaction between the alkali catalyst used in the esterification reaction and the starting fatty acid, and when the esterification reaction is insufficient and the amount of fatty acid exceeds the stoichiometric amount. In some cases, it may contain unreacted fatty acids.

  Thus, since PoGE is a complex mixture, it has been difficult to identify the overall characteristics of PoGE by conventional chemical analysis. For example, even if the average degree of esterification of PoGE is similar or the same, the physical properties such as emulsion stability may be significantly different, and the physical properties can be obtained only by conventional chemical analysis methods such as the average degree of esterification and unreacted PoG. Insufficient grasping has caused inconvenience in the physical property evaluation method. Therefore, “cloud point” has been adopted in recent years as a general characteristic rule for polyglycerin fatty acid ester compositions.

  In general, cloud point is defined as the temperature at which a non-ionic surfactant aqueous solution derived from ethylene oxide is separated into two phases due to temperature rise and becomes heterogeneous. As a method for evaluating the physical properties of polyoxyethylene surfactants It is well known (oil and fat terminology: edited by Japan Oil Chemistry Association (Yuki Shobo)). The cloud point is sensitive to the structure and composition of the polyglycerol fatty acid ester and reflects the fatty acid soap, so that the degree of hydrophilicity and the difference in composition can be more accurately identified. Furthermore, since it can measure simply, it is the most excellent as a physical property which represents the characteristic of a polyglycerol fatty acid ester composition. Accordingly, in the polyglycerol fatty acid ester composition, the cloud point is a more useful index than HLB (balance between hydrophilicity and hydrophobicity).

  Since polyglycerin has a large number of hydroxyl groups, PoGE generally has a higher cloud point than the polyoxyethylene-based surfactant and may exceed the boiling point of water. In such a case, it can be easily measured by using an appropriate aqueous salt solution (Japanese Patent Laid-Open No. 9-157386). Usually, the higher the hydrophilicity, the higher the cloud point, and the higher the monoester content, the higher the cloud point even if the esterification rate is the same.

As a cloud point measuring method, it is usually necessary to measure after dissolving a polyglycerol fatty acid ester in 1 to 30% by weight of sodium chloride or sodium sulfate aqueous solution. The conditions differ depending on the solubility of the target sample, but in the case of the present invention, first, polyglycerin fatty acid ester is dispersed in a 20% by weight sodium chloride aqueous solution so as to be 1% by weight, stirred while heating, and uniformly A simple 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 state of the heterogeneous aqueous solution. This non-uniform state is called “cloud point”, and the temperature is obtained in the present invention. If the temperature is lower than 0 ° C., the melting point of the ice is not higher than the melting point. If the temperature is higher than 100 ° C., the boiling point of the water is not lower.
The amount of polyglycerin fatty acid ester added to the milk beverage is usually 0.01 to 0.1% by weight.

[Sucrose fatty acid ester less than HLB10]
As a sucrose fatty acid ester of less than HLB 10, the monoester content is usually 0% by weight or more and 50% by weight or less, preferably 30% by weight or more and 50% by weight or less, and the ester content of diesters or more is usually 50% by weight or more. 100% by weight or less, preferably 50% by weight or more and 70% by weight or less. Examples of the constituent fatty acid include saturated or unsaturated fatty acids having 14 to 22 carbon atoms such as myristic acid, palmitic acid, stearic acid, behenic acid, and oleic acid. Among these, fatty acids having 14 to 18 carbon atoms are preferable, and saturated fatty acids are preferable. Among them, it is preferable that 70% by weight or more of the constituent fatty acid is stearic acid, in particular, the monoester content used for the purpose of preventing precipitation of milk beverage is 30% by weight, and the ester content of diester or more is 70% by weight. A sucrose fatty acid ester in which 70% by weight or more of the constituent fatty acid is stearic acid is most preferable. In consideration of dispersibility in water, the HLB is usually 5 or more and preferably 9 or less. The amount of sucrose fatty acid ester of less than HLB 10 added to the milk beverage is usually 0.01 to 0.1% by weight.

The added amount of each component in the milk beverage of the present invention is preferably such that the weight ratio of polyglycerin fatty acid ester / sucrose fatty acid ester less than HLB 10 is 99/1 to 1/99, and 5/1 to 1/5. More preferably it is. In particular, it is most preferable when the weight ratio is 1/1, which is effective for suppressing the floating of milk components. The weight ratio of polyglycerin fatty acid ester / HLB10 or higher sucrose fatty acid ester is not particularly limited, but is usually 0.5 to 1/1, preferably 0.6 to 0.7 / 1.
[Coffee extract]
The coffee beans used in the milk beverage of the present invention are not particularly limited, and the same type of coffee beans may be used or two or more types of coffee beans may be mixed and used. Usually roasted coffee beans are used. As a roasting method, an apparatus such as a direct-fire roaster or a hot-air roaster is used, and heating is performed at a temperature of 200 to 300 ° C. until a target L value is reached.

  L value is used as an index representing the degree of roasting of coffee beans. The L value is a value obtained by measuring the lightness of roasted coffee beans with a color difference meter, with black representing L value 0 and white representing L value 100. Therefore, as the roasted coffee beans become deeper, the color of the roasted beans becomes darker, so the L value becomes lower and the bitterness of the coffee beverage becomes stronger. Conversely, the shallower the roast, the higher the L value and the stronger the acidity. Usually, coffee beans with a roasting degree of 15 to 35 are used for the production of coffee beverages, but if the L value is less than 15, the bitterness of the coffee beverage is not preferred. When the L value exceeds 35, the acidity becomes strong, which is not preferable.

Next, the roasted coffee beans are pulverized using a coffee mill or the like so as to have a predetermined particle size, and extracted with hot water. Specifically, the ground coffee beans are usually poured into hot water at 90 to 98 ° C., stirred for about 10 minutes, and then insolubles are removed by filtration to obtain a coffee extract.
In the milk beverage of the present invention, the content of the coffee extract is usually 5 to 10% by weight, preferably 5 to 7% by weight, in terms of green beans. When the content of the coffee extract is less than 5% by weight in terms of green beans, even if the combination of the emulsion stabilizer of the present invention is used, suppression of the levitation of milk components may be insufficient. Moreover, when content of a coffee extract exceeds 10 weight% in conversion of green beans, the bitterness of coffee is too strong and it is not preferable as milk coffee.

[Milk ingredients]
Examples of milk components used in the milk beverage of the present invention include cow's milk, whole milk powder, skin milk powder, fresh cream and the like, and proteins such as skim milk powder and milk fat such as butter and milk oil are individually added and adjusted. May be. Among these, milk can be preferably used because the smoothness of mouthfeel is not impaired as compared with milk powder. The content of the milk component in the milk beverage is usually 4 to 60% by weight, preferably 8 to 25% by weight in terms of milk.
[Other ingredients]
The milk beverage of the present invention may contain other emulsifying stabilizers, known compounding agents such as sugar, fragrance, and vitamin. Examples of other emulsion stabilizers include lecithin, lysolecithin, glycerin fatty acid ester, diglycerin fatty acid ester, sorbitan fatty acid ester, and organic acid monoglyceride.

[milk beverage]
Examples of the milk beverage of the present invention include milk coffee and milk tea, and milk coffee is preferred.
[Method for preparing milk beverage]
The milk beverage of the present invention is usually prepared in advance with an emulsion stabilizer containing a sucrose fatty acid ester of less than HLB10, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of HLB10 or more, and this is mixed with other ingredients. To prepare. This emulsion stabilizer may contain other components added to the milk beverage. The total content of the sucrose fatty acid ester of less than HLB10, polyglycerin fatty acid ester, and HLB10 or more contained in the emulsion stabilizer is usually 50 to 100% by weight, preferably 70 to 100% by weight, More preferably, it is 90-100 weight%. The blending ratio of each emulsifier contained in the emulsion stabilizer is usually the same as the blending ratio of each emulsifier in the above-described milk beverage. The amount of the emulsion stabilizer of the present invention added to the milk beverage is usually 0.05 to 0.3% by weight. The milk beverage of the present invention can also be prepared by individually mixing a sucrose fatty acid ester of less than HLB10, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of HLB10 or more with other components.

The milk beverage of the present invention is usually mixed with coffee or tea extract and milk components such as sugar and milk, then mixed with an aqueous solution of an emulsion stabilizer, and further adjusted with sodium bicarbonate to adjust the pH, and then using a homogenizer. Perform homogenization.
Normally, a pH adjuster (sodium bicarbonate, etc.) is added before heat sterilization to adjust the pH of milk drinks. However, if the amount of sodium bicarbonate added is large, a heated odor of sodium bicarbonate is produced, and coffee Since the original aroma changes, the pH of milk coffee is preferably 5.0 to 7.0, more preferably 6.0 to 6.6.

  The milk beverage thus prepared is sterilized by heating. The sterilization method may be either retort sterilization or UHT sterilization, but in the present invention, it is preferable to perform UHT sterilization. The UHT sterilization used in the present invention is an ultra-high temperature sterilization at a sterilization temperature of 130 to 150 ° C. and a sterilization value (F 0) of 121 ° C. corresponding to 10 to 50. 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 a beverage, a steam infusion method in which a beverage is injected into steam, and an indirect heating method using a surface heat exchanger such as a plate or tube. For example, a plate type sterilizer can be used.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In addition, the ratio,% and part all represent the weight ratio, weight% and part by weight.
[Examples 1 and 2 ]
0.65 kg of roasted coffee beans (Colombia EX) having an L value of 26 was extracted with 6.5 kg of 95 demineralized water to obtain a coffee extract. Add 6 kg of coffee extract, 0.8 kg of milk, 0.5 kg of granulated sugar, and an aqueous solution prepared by dissolving 0.007 kg of the emulsion stabilizer listed in Table 1 in 0.993 kg of demineralized water at 50 ° C. 10 kg. Sodium bicarbonate was added to this solution to adjust the pH after sterilization to 6.4, and this was homogenized using a high-pressure homogenizer at a temperature of 60 to 70 ° C. and a pressure of 150 kg / 50 kg, and then plate-type UHT sterilization. Sterilize with the equipment (Hisaka STS-100) under the conditions of sterilization temperature of 137 ° C and sterilization time (hold time) of 60 seconds (F0 = 40), fill into a 500ml PET bottle under aseptic condition and cool the milk coffee. Obtained.

About the coffee immediately after sterilization, the median particle size (The particle size which the sum total of the appearance frequency of a particle size becomes 50%) measurement was performed by HOLIBA product and LA-500. Further, the cream-off amount (emulsification stability) was evaluated by TurbiScan MA2000 manufactured by Formula Action. Further, these milk coffees were stored at 40 ° C. for 2 months, and the redispersibility of the milk ring formed on the liquid surface due to the floating of milk components was evaluated. The evaluation results are shown in Table-1.
[Comparative Examples 1-3 ]
It carried out similarly to Examples 1-2 except having used the emulsion stabilizer of Table-1. The evaluation results are shown in Table-1 .

In addition, the emulsion stability in Table-1 was evaluated as follows.
<Measurement of cream-off amount by Turbscan MA2000>
By scanning the light source in the vertical direction of the sample tube at regular time intervals, the backscattered light from the sample is detected, and the rate of change in the backscattered light intensity with respect to the measurement time is observed, so that the cream-off state is detected. I can grasp it. By measuring the upper part of the sample tube, information on the amount of cream-off can be obtained. As the rate of change in the backscattered light intensity increases with time, the amount of cream-off increases and the emulsification stability is poor. Therefore, the milk component ascent rate (straight line obtained by plotting the measurement time and the rate of change of the backscattered light intensity) was calculated, and the emulsion stability in Table 1 was evaluated as follows.

* Criteria for cream-off amount ◎: Milk component ascent rate is less than 4 dB (%) / day ○: Milk component ascent rate is 4 dB (%) / day or more and less than 5 dB (%) / day Δ: Milk component ascent rate is 5 dB ( %) / Day or more and less than 6 dB (%) / day ×: Milk component ascent rate is 6 dB (%) / day or more dB (%) is an abbreviation of deltaBackscattering, which is the rate of change of the backscattered light intensity. The ring redispersibility was evaluated as follows.

* Evaluation criteria for redispersibility of milk ring ◎: Dispersed by lightly shaking ○: Dispersed when shaken for a while △: Difficult to disperse due to cream adhering to the wall

Claims (8)

A milk beverage containing a sucrose fatty acid ester of HLB10 or higher, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of less than HLB10, wherein the weight ratio of the polyglycerin fatty acid ester / HLB10 or higher sucrose fatty acid ester is 0.5 to A milk beverage characterized by being in the range of 1/1 . The milk beverage according to claim 1, wherein the weight ratio of polyglycerin fatty acid ester / sucrose fatty acid ester less than HLB 10 is 99/1 to 1/99. The milk drink according to claim 1 or 2, wherein the polyglycerin fatty acid ester has a cloud point of 80 ° C or higher measured at a concentration of 1% by weight in a 20% by weight aqueous sodium chloride solution. The milk beverage according to any one of claims 1 to 3, which has been UHT sterilized. The milk drink according to any one of claims 1 to 4, wherein the milk drink is milk coffee. The dairy drink according to claim 5, wherein the coffee extract contained is extracted from coffee beans having a roasting degree of 15 to 35. The milk beverage according to claim 5 or 6, wherein the content of the coffee extract is 5 to 10% by weight in terms of green beans. An emulsion stabilizer for milk beverages comprising a sucrose fatty acid ester of HLB10 or higher, a polyglycerin fatty acid ester, and a sucrose fatty acid ester of less than HLB10, wherein the weight ratio of polyglycerin fatty acid ester / HLB10 or higher sucrose fatty acid ester is An emulsion stabilizer for milk beverages, characterized in that it is in the range of 0.5 to 1/1 .