JPH0829048B2 - Aseptic green tea - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to aseptic green tea excellent in flavor, color tone, and appearance (feeling of suspension).

<Prior Art> Soluble green tea powder, which is instant green tea powder, is well known.

Further, as a technique for storing green tea in a liquid state for a long period of time, for example, a method in which a beverage from which a microorganism and an enzyme have been removed from an undiluted solution of beverage such as tea by using an ultrafiltration device is produced by filtration (Japanese Patent Application Laid-Open Publication No. Sho.
No. 60-110271) is known.

<Problems to be Solved by the Invention> However, the soluble green tea powder must be dissolved in hot water or the like for drinking.

On the other hand, green tea obtained by simply subjecting green tea to ultrafiltration treatment has a large loss of chlorophyll and other flavor components in the green tea, so that the green color and flavor of the green tea are significantly impaired.
There was such a problem.

<Means for Solving Problems> The inventors of the present invention have solved the above problems and allowed green tea to be stored in a liquid state for a long period of time, and have the original flavor, color tone, and appearance (suspension) of green tea. We conducted an intensive research to provide the green tea we had. As a result, it was found that the above object can be achieved by aseptically mixing the sterile green tea extract solution subjected to the sterilization filtration treatment and the tea leaf powder subjected to the sterilization treatment.

The gist of the present invention completed based on the above findings is aseptic green tea characterized by being sterilely mixed with a sterile green tea extract that has been subjected to sterilization filtration treatment and tea leaf powder that has been subjected to sterilization treatment. is there.

 Hereinafter, the present invention will be described in detail.

The sterile green tea extract in the present invention can be obtained by subjecting the green tea extract obtained by boiling tea leaves to sterilization filtration.

The temperature condition for boiling is not particularly limited and may be appropriately determined by the practitioner. Further, it is preferable that the green tea extract obtained by boiling and separating from the tea leaves is appropriately cooled if necessary. Thereby, browning of the green tea extract can be effectively prevented.

The sterilization filtration treatment of the green tea extract is performed using an ultrafiltration membrane, an ultraprecision filtration membrane, a precision filtration membrane or the like. For example, 0.45
By using a membrane having a pore size of μ, Escherichia coli, Serratia marcescens, Bacillus subtilis, etc. can be completely removed.

The sterile green tea extract that has been subjected to the sterilization filtration treatment is aseptically mixed with the tea leaf powder that has been sterilized. As a result, the chlorophyll, the flavor component and the like removed by the sterilization filtration process can be replenished from the tea leaf powder into the sterile green tea extract. It is desirable to adjust the above mixing so that the tea leaf powder content is 0.001 to 0.2% by weight, preferably 0.005 to 0.1% by weight, based on the sterile green tea extract. When the ratio of the above-mentioned tea leaf powder is less than 0.001% by weight, the original flavor, color tone and appearance (suspension) of green tea cannot be exhibited, while when the above ratio is more than 0.2% by weight, it becomes green tea. Bitterness is not preferable.

The above-mentioned tea leaf powder refers to a powder obtained by pulverizing tea leaves so as to pass through 200 mesh, preferably 250 mesh. When the tea leaf powder that does not pass through 200 mesh is used, the tea leaf powder settles down and the appearance (suspension) as green tea is not exhibited. In addition, since the green tea extract and the tea leaf powder do not mix well with each other, the original taste of green tea is not exhibited, and further, the tea leaf powder is rough on the tongue and feels uncomfortable in taste when drinking.

The method for pulverizing the above-mentioned tea leaves may be carried out in the usual manner, but in order to prevent the quality deterioration of the tea leaves caused by the heat generated during the pulverization,
It is desirable to employ a freeze-grinding method in which the tea leaves are previously frozen and then ground.

The crushed tea leaves must be sterilized because they are aseptically mixed with the sterile green tea extract as described above.

Examples of the sterilization treatment include heat sterilization and electron beam sterilization.

When heat sterilization is performed in the above sterilization treatment,
It is desirable that the pH of the tea leaf powder before heat sterilization is adjusted to 6.5 to 7.5 by adding an alkaline agent and water to the tea leaf powder. By heating the tea leaf powder in this state, browning of the tea leaf powder due to the heating can be effectively prevented.

When the above heat sterilization treatment is performed, quality deterioration due to heating of the tea leaf powder is prevented as much as possible, for example, 130
It is desirable to carry out uniform heat treatment at a temperature of ~ 150 ° C for a short time.

When the tea leaf powder sterilized by the above heat treatment is mixed with the sterile green tea extract, the alkaline agent and water which are heat treated together with the tea leaf powder are also mixed into the sterile green tea extract. The mixing is preferably adjusted so that the total weight of the tea leaf powder, the alkaline agent and water is 0.02 to 2.0% by weight with respect to the sterile green tea extract.

Examples of the above-mentioned alkaline agent include sodium hydrogen carbonate, potassium phosphate, etc. Among them, it is preferable to use sodium hydrogen carbonate which does not greatly affect the taste. When using the sodium hydrogen carbonate, in order to adjust the PH of the tea leaf powder within the above range, the sodium hydrogen carbonate is added in an amount of 0.5 to 15% by weight, preferably 0.7 to 10% by weight, based on the tea leaf powder. Add in proportion. That is, when the addition amount is less than 0.5% by weight, the tea leaf powder is browned during heat sterilization, while the addition amount is 15% by weight.
When the amount is increased, the browning can be prevented, but the taste of green tea is greatly affected.

Further, the addition of the above-mentioned water can easily dissolve the alkaline agent in the tea leaf powder using the water as a medium and can perform sterilization by moist heat, so that the sterilization treatment can be performed at a low temperature in a short time as compared with dry heat sterilization. Is advantageous in that it can be applied.

The amount of water added is 2 to 20 with respect to the weight of the tea leaf powder.
Double is preferred. When the amount added is less than twice, the tea leaf powder cannot be uniformly mixed with water, and thus the heat sterilization of the tea leaf powder is not uniformly performed. On the other hand, when the amount of water added is more than 20 times, the amount of water heat-treated with the tea leaf powder mixed with the green tea extract, that is, the amount of water having a heated odor generated by the heat treatment is Will increase. As a result, the finally produced green tea has a large sense of heating odor and loses the original flavor of green tea.

(Example 1) 25 g of tea leaves were added to 500 ml of hot water at 60 ° C., and after boiling treatment, the tea leaves were taken out to obtain 460 ml of green tea extract. Then, the green tea extract was cooled to room temperature and then filtered through a sterilization filter to obtain a sterile green tea extract. The filtration conditions are Glassf
iber filter, 0.65μMembrane filter, 0.45μMembrane
Three-step filtration was performed with a filter.

Next, after freezing the tea leaves, the tea leaves were crushed to a 280 m
10 g of tea leaf powder that passed through the esh was obtained. Then, 50 g of the tea leaf powder and 0.18 g of sodium hydrogen carbonate were added and mixed, and the pH was adjusted to PH6.8. Next, the tea leaf powder containing sodium hydrogen carbonate and water (hereinafter simply referred to as "hydrated tea leaf powder") is stored and sealed so as to be spread thinly in the retort bouch, sterilized at 135 ° C for 5 seconds, and heated. A sterilized hydrous tea leaf powder was obtained.

Then, 100 ml of the above-mentioned aseptic green tea extract and 0.15 g of heat-sterilized hydrous tea leaf powder (tea leaf powder 0.025 g) were aseptically mixed to obtain aseptic green tea excellent in flavor and color tone.

<Effects of the Invention> As described above, the green tea of the present invention has the original taste, color tone, and appearance (feeling of suspension) of green tea immediately after being boiled, and since it is subjected to aseptic processing, Green tea can be stored in liquid form for a long time. Also, delicious green tea can be drunk anywhere anytime without the trouble of dissolving with hot water.

Claims (7)

[Claims] 1. A sterile green tea extract which has been sterilized and filtered.
Aseptic green tea, characterized by being aseptically mixed with sterilized tea leaf powder. 2. The sterilized tea leaf powder is mixed with 0.001 to 0.2% by weight of the sterile green tea extract which has been sterilized and filtered. Aseptic green tea described. 3. The sterile green tea according to claim 1, wherein the sterilization treatment of the tea leaf powder is heat sterilization. 4. The sterile green tea according to claim 3, wherein the tea leaf powder before heat sterilization is adjusted to PH 6.5 to 7.5 by adding and mixing an alkaline agent and water. 5. The sterile green tea according to claim 4, wherein the alkaline agent is sodium hydrogen carbonate. 6. The sterile green tea according to claim 5, wherein the added amount of sodium hydrogen carbonate is 0.5 to 15% by weight based on the tea leaf powder. 7. The amount of water added is 2 to the weight of the tea leaf powder.
20 times, aseptic green tea according to claim (4).