JP7145660B2 - Method for producing green tea beverage - Google Patents

Description

The present invention relates to green tea beverages.

BACKGROUND ART Packaged green tea beverages that are ready-to-drink at any time are widely popular. In addition, as packaged green tea beverages have become more popular, people are drinking them not only to quench their thirst, but also to enjoy the aroma and taste of green tea beverages. Consumer demand for fragrance and taste is increasing year by year.

In such container-packed green tea beverages, it is common that a certain period of time (preservation period, etc.) elapses from the time of production to the time of drinking. Therefore, green tea extract is sterilized by heating in order to prevent the growth of microorganisms during the storage period. Specifically, according to the standards of the Food Sanitation Law, it is necessary to sterilize at 120 ° C. for 4 minutes or more, or under conditions with an equivalent sterilization strength. The sterilization treatment is performed under the conditions described in Document 1).

JP-A-06-343389

It is an object of the present invention to provide a novel technology that enables a green tea beverage to have a green aroma and spread of aroma while suppressing the growth of microorganisms.

The present inventor noticed that the green aroma and the spread of aroma felt when drinking a green tea beverage was impaired by the sterilization treatment of the green tea extract as described above, and came up with the idea of improving this.
As a result of intensive research, the present inventors have found that the extract is heated at a heating temperature of 70° C. or more and 110° C. or less for 30 seconds or less, and at the same time, filtration is performed using a filter with a pore size of 0.22 μm or less. The present inventors have found that it is possible to suppress the growth of microorganisms while making it possible to feel the green scent and the spread of the scent more than before, and completed the present invention.

In the present specification, the term "green scent" refers to green grass-like and young leaf-like scents.
In addition, the spread of fragrance means that the fragrance spreads in the mouth and passes through the nose, and the green fragrance described above is maintained.

The gist of the present invention is as follows.
[1] Heating the green tea extract at 70 to 110° C. for 30 seconds or less, and before or after the heat treatment, filtering the green tea extract through a filter with a pore size of 0.22 μm or less. A method for producing a green tea beverage, comprising subjecting it to filtration.
[2] The method for producing a green tea beverage according to [1], further comprising adding 100 to 500 ppm of catechins to the green tea beverage.
[3] When the heating temperature in the heat treatment is X (° C.) and the heating time is Y (seconds), at least one of the following relationships (a) and (b) is satisfied. The method for producing a green tea beverage according to [1] or [2], wherein the green tea extract is heated.
(a) 75≦X≦110, 0<Y≦−0.74286X+85.71429
(b) 70≤X≤85, 0<Y≤30
[4] Heating the green tea extract at 70 to 110° C. for 30 seconds or less, and before or after the heat treatment, filtering the green tea extract through a filter with a pore size of 0.22 μm or less. A method for improving the green aroma and the spread of the aroma in a microbial growth-suppressed green tea beverage, the method comprising subjecting the beverage to filtration.

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide a novel technology that can suppress the growth of microorganisms in a green tea beverage and make it possible to feel the green aroma and the spread of the aroma more when drinking.

4 is a graph showing the relationship between heating temperature (X, °C) and heating time (Y, seconds) in Examples.

One embodiment of the invention is described in detail below.
This embodiment relates to a method for producing a green tea beverage, in which a heat treatment is performed by heating the green tea extract at 70 to 110° C. for 30 seconds or less; Including subjecting to filtration treatment using a filter of 22 μm or less.

As used herein, green tea beverages refer to green tea leaves (steamed tea, sencha, gyokuro, matcha, bancha, Tea classified as non-fermented tea such as gyokuryokucha, kamairicha, and Chinese green tea) is a general term for beverages containing an extract (green tea extract) extracted using water or hot water.
The green tea extract is not particularly limited, and examples include a liquid consisting only of an extract obtained by extracting green tea, a liquid obtained by concentrating or diluting the extract, and the like, and obtained by concentrating and drying these liquids. The extract may be dissolved or dispersed again in water or the like.
In addition, a mixture of extracts extracted from green tea leaves of different types may also be used. It may be the obtained extract.

The conditions for extracting tea leaves are not particularly limited, and can be appropriately set by those skilled in the art in consideration of the type, amount, composition, etc. of the tea leaves used.
In the extraction step, a general extraction method can be employed, and conventionally known extraction methods such as steam distillation, liquefied carbon dioxide gas extraction, alcohol extraction, and hot water extraction can be used. The type of extraction solvent used for extraction is not particularly limited, but when water is used as the extraction solvent, it is preferable to use water purified by deionization exchange treatment or distilled water. They are inexpensive, readily available, and can be safely prepared and applied to extraction equipment. Extraction solvents other than water include ethanol and other hydrophilic organic solvents. In addition, for the purpose of improving extraction efficiency, so-called food additives such as carbonate (sodium bicarbonate (sodium bicarbonate), etc.), phosphate, ascorbate, ascorbic acid, etc. may be added to the extraction solvent as appropriate. .
The extraction temperature is not particularly limited, but may be, for example, 35°C or higher and 100°C or lower, and the upper limit temperature is preferably about 65 to 75°C. If the extraction is performed within the above temperature range, the extraction efficiency is high. The extraction time is also not particularly limited, but it is preferably performed within the range of 5 minutes or more and 60 minutes or less. If the extract is obtained in the above extraction time, it tends to be easy to extract each component of sweetness and aroma while suppressing flavor change and dissipation of aroma components due to heat. This makes it easier to obtain a tea beverage with excellent palatability.
From the viewpoint of bacteriostatic effect and flavor (deliciousness), in the production of the green tea beverage according to the present embodiment, catechins are added to 100 to 500 ppm (more preferably 200 to 500 ppm, still more preferably 300 to 500 ppm). It is preferable to contain it in the beverage at the content.

The step of making the content of catechins 100 to 500 ppm includes preparing a green tea extract in which the content of catechins in the beverage is 100 to 500 ppm (specifically, green tea in which the content of catechins in the beverage is 100 to 500 ppm. extraction using leaves, etc.). Also, catechins may be added to the obtained green tea extract, and the content of catechins in the resulting green tea beverage may be adjusted to 100 to 500 ppm, and is not particularly limited.
As used herein, catechins refer to unpolymerized monomeric catechins ((+)-catechin, (-)-epicatechin, (+)-gallocatechin, (-)-epigallocatechin, (- )-catechin gallate, (−)-epicatechin gallate, (−)-gallocatechin gallate, and (−)-epigallocatechin gallate), and the content of catechins means the total amount of these.
Moreover, the content of catechins in the green tea beverage can be measured and quantified, for example, by a method using high performance liquid chromatography (HPLC).

In this embodiment, the green tea extract is heated at 70 to 110° C. for a time longer than 0 and 30 seconds or less.
The heating method and apparatus are not particularly limited, and can be appropriately set by those skilled in the art. Examples include ultra-high temperature flash sterilization (UHT sterilization).

In this embodiment, in the heat treatment, the green tea extract is heated at 70 to 110° C. for a time longer than 0 and not longer than 30 seconds. In addition, since the green scent and the spread of the scent can be felt more, when the heating temperature is X (° C.) and the heating time is Y (seconds), at least one of the following (a) and (b) It is preferable to heat the green tea extract so as to satisfy either relationship.
(a) 75≦X≦110, 0<Y≦−0.74286X+85.71429
(b) 70≤X≤85, 0<Y≤30

Furthermore, although the appearance of green tea beverages tends to be brown due to heat treatment, the appearance can be further improved (appearance closer to that of non-heating). It is more preferable to satisfy the relationship of

Further, in the present embodiment, the green tea extract is filtered using a filter with a pore size of 0.22 μm or less to perform sterilization.
The filtration treatment may be performed before or after the heat treatment, and one or more other treatments may be performed between the filtration treatment and the heat treatment. good.
Moreover, the temperature of the green tea extract when subjected to filtration treatment is not particularly limited, and can be appropriately set by those skilled in the art.
Examples of filters with a pore size of 0.22 μm or less include AstroPore PSE Cartridge W (trade name) (manufactured by Fuji Film), LifeASSURE (TM) Filter BNA Series (trade name) (manufactured by 3M Japan), and Sarton Pore Filter Cartridge CES Type. (trade name) (manufactured by Roki Techno Co., Ltd.), phlorodyne II (trade name) (manufactured by Nippon Pall Co., Ltd.) and the like can be exemplified, but are not particularly limited.

Next, an example of the processing flow relating to the method for producing a green tea beverage according to the present embodiment will be described with reference to the case of producing a packaged green tea beverage.
First, tea leaves are subjected to an extraction treatment, followed by filtration to remove solids such as green tea leaves, thereby obtaining a green tea extract.
Next, the obtained green tea extract is subjected to treatments such as dilution and pH adjustment, if necessary, and then subjected to heat treatment at 70 to 110° C. for 30 seconds or less for heat sterilization.
Subsequently, the heat-sterilized green tea extract is filtered using a filter with a pore size of 0.22 μm or less. The filtered green tea extract is filled into a container to obtain a packaged green tea beverage.

The method of encapsulation into a container is not particularly limited, either, and it can be carried out, for example, according to a conventional method. A well-known container can be appropriately selected and used, and the material and shape are not particularly limited. Specific examples of containers include transparent or translucent plastic containers such as PET bottles, transparent or translucent bottles, metal cans such as steel cans and aluminum cans, and paper containers.

As described above, according to the present embodiment, it is possible to improve the green aroma and the spread of the aroma (enhanced when drunk) while suppressing the growth of microorganisms in the green tea beverage.
Therefore, it is possible to provide a green tea beverage with a higher commercial value.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these.

[Preparation of green tea extract (1)]
Using an amount of tea leaves to meet the prescription shown below and 30 times the amount of hot water, the tea leaves were repeatedly stirred and stopped in the hot water for a certain period of time. The treatment was performed for a total of 6-8 minutes. Moreover, the extraction temperature was set to 40°C. Vitamin C (ascorbic acid, Vc), vitamin CNa (sodium ascorbate, VcNa), and sodium bicarbonate were added to the obtained green tea extract so as to have the following contents.
Tea raw material (g/L): 10.0 g/L
VcNa (g/L): 0.40 g/L
Vc (g/L): 0.30g/L
Multilayer (g/L): 0.27 g/L
Tea leaves used: Ichibancha kabusecha

The content of catechins in the green tea extract was 360 ppm. In addition, the measurement conditions are shown below.
A green tea extract to be measured was diluted twice with purified water, filtered through a 0.45 μm syringe filter, and used as a sample for measurement, and measured by high-performance liquid chromatography under the following conditions.
Apparatus: Waters UPLC apparatus set (detector: PDA gradient method)
Mobile phase: 0.5% formic acid (A solution), 0.5% formic acid/methanol (B solution)
Column: Waters Acquity UPLC BEH C18, 1.7 μm
2.1×100mm
Flow rate: 0.3 ml/min Gradient: A/B = 90/10 for 2 minutes, then 65/35 for 11 minutes

[Heat sterilization and filtering]
The tea leaf extract prepared as described above was heat-treated at 75° C. for 4 seconds by UHT sterilization. Subsequently, after cooling the tea leaf extract, it is subjected to a filtration process by passing it through a filter (Surton Pore Filter Cartridge CES type (trade name) (manufactured by Roki Techno Co., Ltd.)) having a pore size of 0.20 μm to obtain the green tea beverage of the example. rice field.

[Inhibition of growth of microorganisms]
After inoculation with 1000 cfu/350 ml of the spore liquid of the microorganisms shown in Table 1, the cells were cultured at 35° C. for 2 weeks or 4 weeks. Three samples were tested for each of 2 weeks and 4 weeks. Moreover, the control (Control) was not inoculated with the spore solution (2 samples).
After culturing, the number of bacteria after culturing was measured on a standard agar medium using 1 ml as a sample, and growth was confirmed.

From the results in Table 1, it can be understood that the growth of microorganisms can be sufficiently suppressed in the green tea beverages of Examples.

[Preparation of green tea extract (2)]
A green tea extract was prepared in the same manner as in (1), except that the tea leaves used were ichibancha kabusecha (a blend of stem tea and tea leaves), and vitamin C, vitamin CNa, and sodium bicarbonate were not added. .

[Heat sterilization and filtering]
The obtained green tea extract was heat-treated under each heating condition shown in Table 2. Subsequently, after the green tea extract was cooled, it was subjected to a filtration process by passing it through a filter (Surton Pore Filter Cartridge CES type (trade name) (manufactured by Roki Techno Co., Ltd.)) having a pore size of 0.20 μm. got a drink.

[sensory evaluation]
A sensory evaluation was carried out by a panel of five experts on the appearance, green aroma, and spread of the aroma.
For the sensory evaluation, an untreated green tea extract that had not been subjected to heat treatment and filtration was used as a control green tea beverage (Control), and the difference from the control was evaluated according to the following 5-grade evaluation criteria.
5: No change at all, 4: Slightly different but almost the same, 3: There is a difference, 2: There is a large difference, 1: Significantly different

In the evaluation results, considering the conventional heating conditions (120 ° C., 4 to 6 minutes), the case where the green scent and the spread of the scent can be felt more than in the case of the heating conditions of 120 ° C. and 4 seconds. , was judged to have passed as being improved.
Table 2 shows the results.

From Table 2, it can be understood that the green tea beverages of Examples that were heat-treated at 70 to 110° C. for 30 seconds or less were improved in terms of green aroma and spread of aroma.
Moreover, it can be understood that by satisfying either relationship (a) or (b) shown in FIG. 1, the green aroma and the spread of the aroma can be further improved.

Claims (4)

A heat treatment is performed by heating the green tea extract at 70 to 110 ° C. for 4 seconds or more and 30 seconds or less, and before or after the heat treatment, the green tea extract is filtered using a filter with a pore size of 0.22 μm or less. A method for producing a packaged green tea beverage, comprising subjecting it to filtration. The method for producing a green tea beverage according to claim 1, further comprising adding 100 to 500 ppm of catechins to the green tea beverage. The green tea extract is heated so as to satisfy 70≦X≦85 and 4≦Y≦30 , where X (° C.) is the heating temperature and Y (seconds) is the heating time in the heat treatment. 3. The method for producing a green tea beverage according to 1 or 2. A heat treatment is performed by heating the green tea extract at 70 to 110 ° C. for 4 seconds or more and 30 seconds or less, and before or after the heat treatment, the green tea extract is filtered using a filter with a pore size of 0.22 μm or less. A method for improving the green aroma and the spread of the aroma in a packaged green tea beverage in which growth of microorganisms has been suppressed, comprising subjecting the beverage to filtration.

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