JPH0779699A - Fresh cream emulsion having acid resistance and heat resistance and its production - Google Patents

Abstract

PURPOSE:To obtain a fresh cream emulsion excellent in acid resistance and heat resistance and capable of producing can coffee drink having fresh cream taste. CONSTITUTION:This fresh cream emulsion is produced by blending fresh cream with a purified whey protein hydrolysate obtained by partially hydrolyzing a whey protein having high beta-lacto-globulin content contained in total proteins and an emulsifier and homogenizing the blend.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fresh cream emulsion and a method for producing the same. The fresh cream emulsion according to the present invention, for example, in the production of coffee beverages,
Even if the retort treatment is carried out by adding it to a compounding solution containing low pH coffee and sweeteners, flavors, etc., it does not cause undesirable phenomena such as oil-off, feathering, agglomeration and cream separation. This phenomenon does not cause such a phenomenon even at room temperature and during heating and circulation, and enables the production of fresh cream-blended canned coffee and the like, which could not be conventionally produced.

[0002]

2. Description of the Related Art Conventionally, milk has been added to coffee beverages, but the pH of the product is 6.3 in order to prevent the protein contained in milk from coagulating and separating.
The above is set. In other words, there is no industrial manufacture of low pH coffee beverages.

The fat contained in milk is coated with milk protein on the surface of fat globules and becomes unstable when retort treated. Therefore, an emulsifier is used. Then, by using an emulsifier, in the current coffee beverage (pH is 6.3 or more), the stabilization of fat globules has been obtained at a practical level, but it is still not sufficient. Furthermore, since fat globules become remarkably unstable at a pH of 6.2 or less, industrial production of coffee beverages having a low pH becomes substantially impossible.

On the other hand, as a method for homogenizing fresh cream to obtain a stable emulsion, the milk cream obtained by centrifuging milk is preliminarily destroyed by a method such as charning, and then the obtained milk is obtained. A method of re-emulsifying a fatty oil component with an emulsifier (JP-A-60-58939), a method of emulsifying an oil component with hydrolyzed whey protein, skim milk powder and an emulsifier (JP-A-2-257838) and the like have been proposed. There is.

[0005]

The fat globules of fresh cream obtained by centrifuging milk have a particle size of 0.1 to 20 μm (average of about 3.4 μm), and the surface thereof is derived from mammary gland cells. It is covered with a hydrophilic coating such as phospholipids, gangliosides and proteins. An emulsified cream obtained by homogenizing such a fresh cream with an emulsifier is extremely unstable in an acidic region.

Therefore, as described above, prior to homogenization, the raw fresh cream is destroyed by a method such as churning to remove the fat globule film, and then an emulsifier is added to emulsify, whereby only the emulsifier is used. A method for stabilizing by obtaining coated fat globules has been proposed (JP-A-60-58939). However, with this method, the process is complicated because the fresh cream is demulsified, and the original flavor of the fresh cream is impaired.

As described above, a method of homogenizing fats and oils with an emulsifier, hydrolyzed whey protein, skim milk powder, etc. has been proposed (JP-A-2-257838), but severe sterilization conditions such as canned coffee are proposed. Under (121 ℃, about 30 minutes), the fat globule diameter becomes slightly larger in the coffee extract, and the particle size becomes larger even during warm storage, making fat easy to float. Is inevitable.

On the other hand, so far, coffee extract (pH
Since no stable emulsion emulsification method of fresh cream having sufficient heat resistance in an acidic region such as 4.8 to 6.0) has been developed, canned coffee using fresh cream widely used when drinking regular coffee. Was impossible to manufacture.

The present invention solves all of these drawbacks,
It was made for the purpose of developing an excellent method for producing an emulsified fresh cream that is stable in the acidic region without disturbing the flavor of fresh cream and has high stability with no separation of fat globules even under severe sterilization conditions such as retort heating. It is a thing.

[0010]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the inventors continued diligent research from various fields and examined the purified whey protein hydrolyzate in detail. The importance of the β-lactoglobulin content in the total protein The present inventors have come to the new knowledge that the purified whey protein hydrolyzate having a high β-lactoglobulin content exerts an excellent effect by focusing on the property for the first time.

Based on this novel and useful finding, further detailed investigations were made on the components to be mixed, the processing conditions and other conditions at the time of homogenization, and as a result, the very successful emulsion fresh cream was successfully produced for the first time. The invention was completed. Hereinafter, the present invention will be described in detail.

In order to carry out the present invention, it is necessary to mix a homogenized cream separated from milk with a purified whey protein hydrolyzate having a high β-lactoglobulin content in the total protein to homogenize it. The purified whey protein hydrolyzate used in the present invention is produced by hydrolyzing a processed whey protein product having a high β-lactoglobulin content in the total protein with an enzyme or the like, Before and / or during homogenization 0.05-5%, preferably 0.1-
Add 2%.

Any high β-lactoglobulin purified whey protein hydrolyzate can be used as long as the β-lactoglobulin content is 70 to 95%, preferably 80% or more of the total protein, and its production can be carried out. , For example, as follows.

First, a purified whey protein solution having a high β-lactoglobulin content in the total protein is prepared. The concentration is 1 to 10% (w / v), preferably 2 to 5% (w / v), and the pH is adjusted to 7.0 to 8.0 depending on the enzyme used. As the purified whey protein having a high β-lactoglobulin content in the total protein, any purified protein having a β-lactoglobulin content of 70% or more of the total protein can be used. For example, whey protein concentration Thing (W
hey Protein Concentrate, W
PC) and whey protein isolate (Whey Prot)
A processed whey protein product such as ein Isolate (WPI) can be advantageously used. Not only whey protein-treated products, but also raw materials having a low β-lactoglobulin content can be used as long as they are purified to a desired value.

The purified protein solution prepared as described above is
To this, 0.01 to 5% (preferably 0.1 to 5) of proteolytic enzyme such as trypsin, pepsin, papain, bromelain and various proteases is added to the protein.
0.5%) and added, and reacted at 40 to 60 ° C. for 30 minutes to 6 hours (depending on the enzyme used, but preferably 1 to 3 hours) to obtain a hydrolyzate. Hydrolysis of purified protein
As mentioned above, in addition to the enzyme, acid hydrolysis such as hydrochloric acid is also possible.

By homogenizing the fresh cream by adding and blending the partial hydrolyzate of the purified whey protein thus prepared, a stable fresh cream emulsion can be produced. , The fat globule diameter can be made sufficiently small (1 μm or less), and a more excellent fresh cream emulsion can be obtained.

As the emulsifier, polyglycerin fatty acid ester, organic acid monoglyceride, sucrose fatty acid ester, lecithin and other various emulsifiers (HLB5 to 16) are used.
Or two or more kinds in combination. The addition amount is 0.01-5%
(Preferably 0.5 to 1.0%), and is added before and / or during homogenization.

By using an emulsifier together, the fat particle size can be reduced, but as a result of further investigation, when the fat concentration during homogenization exceeds 30%, the fat particle size becomes 1 μm or more, and can coffee is When stored at high temperature, the cream tends to separate, so the fat concentration during homogenization is preferably 30% or less. In the present invention, the milk fat percentage during homogenization is 2 to 30% (preferably 10-20%)
Even better results are obtained.

[0019]

EFFECTS OF THE INVENTION The fresh cream emulsion thus obtained has excellent acid resistance and heat resistance, and imparts the flavor and texture of fresh cream to acidic foods and drinks subjected to severe heat treatment such as retort sterilization. You can Therefore, according to the present invention, it has become possible for the first time to advantageously produce canned coffee with fresh cream, which could not be produced conventionally.

Specifically, for example, the following remarkable effects are also exhibited. (1) After the fresh cream emulsion was added to the coffee extract (pH 4.8 to 6.0) so that the fat concentration was 0.1 to 2%, and the retort treatment (121 ° C, 30 minutes) was performed. However, the fat particle size is the same as before retort treatment. (2) Even when the canned coffee is stored at a high temperature (55 to 65 ° C.), the fat particle size does not change, the cream does not float, and the redispersibility is good. (3) The fresh cream emulsion retains the flavor of the original fresh cream and has a very good flavor when added to coffee.

Examples of the present invention will be described below.

[0022]

Example 1 Purified whey protein (a whey protein isolate having a β-lactoglobulin content of 95% of the total protein) was dissolved in 4% concentration, and 1N NaOH was added.
After adjusting the pH of the solution to 8.0 with trypsin (NO
(Manufactured by VO) was added so as to be 0.2% of the protein amount, and reacted at 60 ° C. for 3 hours.

The reaction solution was heated at 85 ° C. for 10 minutes to deactivate the enzyme, and then concentrated under reduced pressure so that the solid content was 40%.
The reduced-pressure concentrate was spray-dried to obtain a purified whey protein hydrolyzate (powder).

Similarly, unpurified whey protein (β-lactoglobulin content in the total protein is 6
5%) is also hydrolyzed by trypsin,
A crude whey protein hydrolyzate (powder) was obtained.

Each of these hydrolyzates was homogenized with the formulations (1 to 7) shown in Table 1 below to obtain 7
A variety of prepared creams was obtained.

[0026]

[Table 1]

Each of the prepared creams thus obtained was mixed with 90 parts of the coffee extract (6 g / 100 g of green beans) of the prepared cream, and the pH was adjusted with a 10% NaOH solution.
Adjusted to 6.0, 5.5 and 5.0 respectively, and 121
Autoclave sterilization was performed at 10 ° C. for 10 minutes, and the fat particle size before sterilization and the fat particle size after sterilization were measured by a laser particle size distribution meter, and the results shown in Table 1 were obtained.

As is clear from the above results, Formulations 3 and 6
Other than the above, the particle size after heating was obviously larger than that before heating, and in the formulations 5 and 7, fat aggregated after heating and floated on the liquid surface.

[0029]

Example 2 Using the prepared creams of Formulations 3 and 5 shown in Example 1, coffee extract (green beans 10 g / 100) was used.
g) 50 parts, sugar 6 parts, prepared cream 10 parts, purified water 3
After preparing a canned coffee mix (pH 6.0) in a ratio of 4 parts and performing retort treatment (123 ° C., 20 minutes), 55 ° C.
And stored for 14 days.

The fat particle size (μ) was measured during the storage period, and the floating of the fat was visually observed. The results are shown in Table 2 below. The results revealed that canned coffee using the prepared cream of Formulation 3 was excellent.

[0031]

[Table 2]

Front page continued (72) Inventor Naobu Shibukawa 1-21-3 Sakaemachi, Higashimurayama, Tokyo Meiji Dairy Co., Ltd. Central Research Laboratory

Claims (8)

[Claims] 1. A fresh cream separated from milk is blended with a purified whey protein hydrolyzate obtained by partially hydrolyzing a treated whey protein product having a high β-lactoglobulin content in the total protein, followed by homogenization. A method for producing a fresh cream emulsion, comprising: 2. The method according to claim 1, wherein the processed whey protein product is a whey protein concentrate or a whey protein isolate. 3. The purified whey protein hydrolyzate comprises:
Β-lactoglobulin occupying 70% of all proteins
The method according to claim 1 or 2, wherein the content is 95%, preferably 80% or more. 4. The purified whey protein hydrolyzate is added in an amount of 0.05 to 5 before and / or during homogenization of fresh cream.
%, Preferably 0.1 to 2% is added, The method of any one of Claims 1 to 3 characterized by the above-mentioned. 5. The milk fat concentration during homogenization is 2 to 30.
%, Preferably 10-20%. 5. A method according to any one of claims 1 to 4, characterized in that it is 10-20%. 6. An emulsifier (HLB5-1) for homogenization.
6) The concentration is 0.01 to 5%, The method according to claim 1, wherein the concentration is 0.01 to 5%. 7. A fresh cream emulsion produced by the method according to any one of claims 1 to 6. 8. The fresh cream emulsion according to claim 7, wherein the fresh cream emulsion is for coffee beverages.