JP3047608B2 - Milk drink manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a milk beverage, and more particularly to a method for producing a milk beverage containing a coffee extract or fruit juice. More specifically, the present invention relates to a method for producing a milk beverage containing a coffee extract or a milk beverage containing a fruit juice, which does not cause aggregation of proteins and the like and is stable even when stored for a long time.

[0002]

2. Description of the Related Art When manufacturing milk drinks containing coffee extract extracted from coffee beans and milk drinks containing juice such as strawberry, orange, apple, melon, etc., acids contained in the coffee extract or juice are used. Milk protein components such as casein undergo aggregation and separation due to tannins and pectins.
Conventionally, in order to prevent such a phenomenon, a) a method in which a large amount of a pH adjuster such as sodium bicarbonate is added to adjust the pH of the milk drink to about 6.5 to 7.0, and b) carrageenan A method for stabilizing milk proteins using natural polymer substances such as carboxymethylcellulose or chemically treated polysaccharides as stabilizers, c) Aggregates formed by adding milk to coffee extract or juice D) a method of removing pectins, tannins, and acids contained in fruit juice by a treatment such as ultrafiltration or electrodialysis to prevent aggregation of milk proteins (JP-A-59-143574);
Further, e) a method of preventing the sedimentation of aggregates by increasing the viscosity of the milk beverage has been performed.

[0003] However, these methods only remove the cause component of milk protein aggregation, indirectly stabilize the milk protein by giving a charge to the milk protein, or remove the aggregated milk protein. Yes, it did not mean that the milk protein itself did not have the property of non-aggregation. For example, when fresh juice is added to a juice-containing milk beverage produced by a conventional method, milk proteins are also aggregated and separated, and when heat treatment such as retort sterilization is performed, milk proteins are similarly aggregated. Often do. In addition, a milk drink containing fruit juice whose pH has been adjusted to near neutrality has the disadvantage that the refreshing acidity of the original fruit juice is lost and only the sweetness is increased. Similarly, the milk beverage containing the coffee extract whose pH has been adjusted to near neutrality has lost the original flavor, especially the sourness, of the coffee extract.

[0004]

SUMMARY OF THE INVENTION The objects of the present invention are as follows: 1) In the case of a milk beverage containing a coffee extract, a milk containing a coffee extract that does not use or use a non-protein stabilizer such as carrageenan, which has been conventionally used. Beverage manufacturing method,
2) In the case of a juice-containing milk drink, the disadvantages of the conventional method for producing a juice-containing milk drink are solved, without using a stabilizer, and without removing a milk protein aggregation-causing component contained in the juice,
It is an object of the present invention to provide a method for producing a juice-containing milk drink which imparts the property of dissolving or dispersing the milk protein itself without coagulation and is stable against heat treatment such as retort sterilization.

[0005]

Means for Solving the Problems The present inventors have made intensive studies in order to solve the above-mentioned problems, and as a result, have found that trans (1) milk protein and (2) a mixture comprising gelatin and / or gelatin hydrolyzate can be obtained. It has been found that the above problems can be solved by the action of glutaminase, and the present invention has been completed. That is, in the present invention, transglutaminase is allowed to act on a mixture containing (1) milk protein and (2) gelatin and / or gelatin hydrolyzate to stabilize milk protein, and then a coffee extract or fruit juice is added and mixed. A method for producing a dairy beverage, characterized in that:

[0006] In the present invention, animal milk such as milk, skim milk, sheep milk and vegetable milk such as soy milk may be used as raw materials as milk proteins. Furthermore,
Those obtained by diluting, concentrating, or pulverizing them can also be used. On the other hand, as a coffee extract, a coffee bean is subjected to a heat treatment such as roasting, and a powdered product thereof is extracted with water, hot water, and a dried product thereof is dissolved in water or hot water. Can be used. In addition, as fruit juice, strawberry, orange,
Not only juice obtained from fruits such as apple, melon, banana, grape and grapefruit but also juice obtained from fruits and vegetables such as watermelon, carrot and tomato can be used. In addition to the fruit juice obtained by direct squeezing, a heat-treated or diluted fruit juice, an extract extracted from a fruit, and the like can of course be used. Any type of transglutaminase may be used as long as it has a transglutaminase activity, such as a microorganism-derived transglutaminase (see JP-A-1-27471) and a guinea pig liver-derived (see Japanese Patent Publication No. 1-50382). Preferably, a transglutaminase derived from a microorganism is used.

[0007] As a method for stabilizing milk protein in milk in the present invention, it is important to perform the following treatment on milk before mixing with coffee extract and fruit juice. That is, gelatin and / or a gelatin hydrolyzate is dissolved in milk such as cow's milk in an amount of 30 to 1,000 parts by weight, preferably 50 to 500 parts by weight, based on 100 parts by weight of milk protein in milk, and the milk is dissolved therein. 1 to 1 g of protein
The transglutaminase may be added in an amount of 100 units, preferably 5 to 50 units. By this treatment, the milk protein and the gelatin and / or the gelatin hydrolyzate are cross-linked and polymerized into a stabilized milk protein. The reaction temperature in the transglutaminase reaction during the treatment was 4
To 65 ° C, preferably 20 to 55 ° C, and the reaction time is 3 hours to 1 minute, preferably 1 hour to 20 minutes. Of course, the reaction conditions are not limited to the above conditions.

[0008] The milk treated by the transglutaminase reaction as described above is then mixed with a coffee extract or fruit juice, but the mixing ratio is not particularly limited. Usually, the milk is mixed with 100 parts by weight of the final product, a milk beverage. , (1)
In the case of a coffee extract, it is preferable to contain 50 to 90 parts by weight of the coffee extract, and in the case of (2) fruit juice, it is preferable to contain 10 to 50% by weight of the juice. In addition, sugars such as sucrose and sweeteners such as aspartame may be added during mixing. In addition, additives such as a small amount of a fragrance and a small amount of a pH adjuster such as sodium bicarbonate may be added. The milk beverage containing the coffee extract and the fruit beverage containing the juice are subjected to retort sterilization or UHT sterilization (ultra high temperature sterilization), or
Filled aseptically and supplied to the market.

[0009]

According to the present invention, the milk protein itself in milk is stabilized by the action of transglutaminase, so that the milk protein aggregates and separates even if it is subsequently mixed with a predetermined amount of coffee extract and fruit juice. There is no. In addition, an excellent effect of being stable against heat treatment such as retort sterilization or UHT sterilization is recognized. The conditions of the retort treatment and the UHT sterilization may be performed under ordinary conditions described in a textbook.

[0010]

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the embodiments.

(Example 1) Commercially available ingredient-free milk 130
g (containing about 4 g of milk protein), 2 g of acid-treated gelatin (manufactured by Nippi Co., Ltd.) is dissolved while heating, and a transglutaminase having a specific activity of 1 unit / mg (see Japanese Patent Application Laid-Open No. 1-27471). 80 mg (obtained by the method of Example 1) was added, and the mixture was incubated at 55 ° C. for 1 hour. Next, 1.4 g of instant coffee (manufactured by Ajinomoto General Foods Co., Ltd.), 4 g of granulated sugar, and 0.02 g of sodium bicarbonate were dissolved in heated distilled water, and then mixed with the above-described transglutaminase-treated milk. The total amount was adjusted to 1000 g with distilled water, and homogenized with a mixer to obtain a prepared liquid. This preparation was filled in a 250 ml can, sealed, and retorted at 123 ° C for 20 minutes.
After sterilization, it was cooled to room temperature to obtain a canned coffee beverage (sample).

On the other hand, without dissolving acid-treated gelatin in milk,
After the same treatment as that of the sample without adding transglutaminase (control 1), the acid-treated gelatin was not dissolved in milk, and transglutaminase was not added.
Only the amount of sodium bicarbonate was changed to 0.08 g, and then the same treatment as that of the sample was performed (control 2), and transglutaminase previously inactivated was dissolved in milk in which acid-treated gelatin was dissolved. After the addition, the same treatment as the sample (Control 3) was prepared as a control coffee beverage.

Each of the sample, Control 1, Control 2, and Control 3 was evaluated for pH, the aggregation state of milk protein, and whether or not particularly the sourness of the original coffee flavor was maintained. In addition, each coffee-containing milk drink after storage at 55 ° C. for 3 months was similarly evaluated.
The results are shown in Table 1.

[0014]

[Table 1] (Note) * 1 A: No aggregation of milk protein. B: Milk protein is slightly aggregated. C: Milk protein is considerably aggregated. * 2 ○: Almost the original sourness of coffee is maintained. Δ: Coffee original acidity is maintained slightly. ×: Almost no original acidity of coffee is maintained.

As can be seen from Table 1, immediately after production and 55
The sample was the best after storage at 3 ° C. for 3 months, and there was no aggregation of milk protein, and the original flavor of coffee, especially the sourness, was maintained. Furthermore, the sample also received the best evaluation in taste evaluation by a sophisticated panelist.

Example 2 Strawberry fruits were cut into small pieces with a mixer and filtered with gauze to remove seeds and the like. The juice thus obtained is hereinafter referred to as primary juice. The primary juice was further centrifuged (5,000 rpm,
After 10 minutes), the supernatant obtained by removing the suspended matter was used as a secondary juice.

On the other hand, acid-processed gelatin (manufactured by Nippi Co., Ltd.) was dissolved in commercially available milk (containing approximately 3% of protein) without component adjustment so as to have a concentration of 1.5%. To this, transglutaminase (for example, the transglutaminase described in Example 1) was added in an amount of 20 units per gram of milk protein, and the mixture was incubated at 37 ° C. for 1 hour. To this milk, the above-mentioned primary juice or secondary juice was mixed so as to be 20% or 40%, respectively, per 100 parts by weight of the final milk drink to prepare a simulated strawberry juice-containing milk drink (sample) ).

As a control, a mixture of milk and fruit juice without any treatment (Control 1) and a sample prepared by dissolving acid-treated gelatin in milk and then inactivating the milk in the same manner as in the sample. The transglutaminase was added, and the same treatment as the sample was performed (control 2).

Table 2 below shows the results of observing the state of the three samples prepared as described above, Control 1 and Control 2.

[0020]

[Table 2] (Note) * 3 ：: A solution state in which milk protein was not aggregated at all and was dispersed well. Δ: Milk protein is slightly aggregated but dispersed. ×: Milk protein is aggregated and separated.

Subsequently, each sample was subjected to a heat treatment at 120 ° C. for 10 minutes by an autoclave, and the results of observation of the state of each sample after the heat treatment were shown in Table 3.
It was shown to.

[0022]

[Table 3] (Note) * 3 Same as Table 2

As a whole, the primary juice that has not been subjected to centrifugation has a characteristic that it has a higher viscosity than the second juice that has been subjected to centrifugation, and milk protein is likely to aggregate (see Table 2).
Also, by adding the acid-treated gelatin to the milk, as can be seen from the results in Table 2, a slight milk protein stabilizing effect was observed, but when the percentage of juice increased, aggregation also occurred, and the effect was insufficient. there were. Moreover, as can be seen from Table 3,
When subjected to the heat treatment, the milk protein was completely aggregated and separated. On the other hand, as is clear from Tables 2 and 3, the samples obtained according to the present invention have no milk protein agglutination separation at all, regardless of the presence or absence of the centrifugation of the juice, and the milk protein is clearly stable. I was Similarly, the sample was quite stable even when subjected to heat treatment. Also, in taste evaluation by a sophisticated panelist, the samples in Tables 2 and 3 were significantly superior in all of taste, flavor, and aroma as compared with the control product. Furthermore, for the sample after the heat treatment,
The juice was further added and diluted, but at that time, the milk protein was stable without aggregation separation.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-59-143574 (JP, A) JP-A-53-118548 (JP, A) JP-A-2-31664 (JP, A) JP-A-3-3 39043 (JP, A) JP-A-3-160957 (JP, A) JP-A-58-149645 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A23C 9/156 A23L 2 / 38

Claims (1)

(57) [Claims] (1) milk protein and (2) gelatin and / or
Alternatively, a method for producing a milk beverage, which comprises mixing a coffee extract or a fruit juice after stabilizing milk protein by allowing transglutaminase to act on a mixture containing a gelatin hydrolyzate.