JPH03277234A - Production of green tea product not causing turbidity - Google Patents

Abstract

PURPOSE:To prevent turbidity and precipitation occurring in cooling and preservation of tea product, by adding an alcohol to a solution of tea. CONSTITUTION:Tea leaves are extracted with water containing >=0.2 pt.wt. calculated as hydroxyl group of an alcohol (e.g. ethyl alcohol) based on 100 pts.wt. solid content of tea solution at 55-95 deg.C or the alcohol is added to the tea solution, filtered, then optionally mixed with an additive such as sweetener or lemon juice and cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing tea products that can prevent turbidity and precipitation that occur when tea products are cooled and stored.

<Prior Art> Generally, as tea products, transparent black tea, green tea, oolong tea, etc., such as canned or bottled lemon tea and straight tea, are known. Among these, for example, black tea products are manufactured by extracting black tea with hot water, filtering it, and mixing it with sweeteners and the like. In the manufacturing process of these transparent tea products, we are trying to prevent the turbidity and sedimentation that occurs when the products are kept cold.

How to prevent this is a major and long-standing issue. It is widely known that the turbidity and precipitation observed in the above tea products upon cooling are caused by the interaction between caffeine and tannins contained in the tea solution.

Therefore, as a method to suppress this turbidity, there is a method of extracting by adding excessive WTM, and a method of extracting by adding an excessive amount of WTM, and using a pH24 adjusting agent.
A method of extracting by raising H'e, a method of enzymatic treatment with tannase, etc., a method of mechanically separating the turbidity as a precipitate by hardening the extract after cooling, or a method of contacting with a polymer resin, silica gel, etc. to remove tannins. Methods for adsorbing and removing such substances have been proposed.

However, F! The method of extraction by adding an excess of i:11M requires 20 times more to be effective! % or more, which is too sweet in terms of flavor and is not practical.Additionally, the method of extraction using the pH adjustment rule gives a salty taste and reduces the flavor when the amount added is large. unfavorable,
It is not effective at low addition amounts, and furthermore, p
H control is required, which is not preferable in terms of process. Furthermore, tannase treatment.

Methods for strengthening the trench, adsorbing and removing tannins, etc.
Each method not only complicates the process and increases the price of raw materials, but also leaves problems in that the original flavor of the tea is lost.
The reality is that no method has been found to prevent turbidity that takes flavor into consideration.

<Problems to be Solved by the Invention> The present invention was made in view of the above circumstances, and its purpose is to reduce turbidity during cold storage.

To produce a tea product that not only prevents precipitation but also has a desirable flavor and color tone without reducing the content of caffeine and tannins that are effective for the original flavor of tea, and without causing a structural change in the composition. The goal is to share methods.

<Means for solving the problem> The above purpose is to extract tea from tea leaves and produce tea products by extracting 0.2 parts of solids in terms of hydroxyl groups per 100 parts of solids in hot tea liquid. This is achieved by a method for producing a tea product that does not cause turbidity, which is characterized by adding the above-mentioned alcohols in advance to the hot water used during extraction, or adding them to the tea solution after extraction.

That is, the present inventor has solved the turbidity and precipitation of tea solutions by adding alcohols having hydroxyl groups that have the effect of suppressing the formation of complexes between caffeine and tannins that cause turbidity and precipitation. The present invention was completed based on the discovery that this can be suppressed.

Next, the present invention will be explained in detail.

The tea products of the present invention include black teas such as lemon tea and straight tea, green teas, oolong teas, etc., and contain caffeine and tannins.

The manufacturing method of the present invention is carried out as follows.

In other words, in the process of extracting tea from tea leaves, alcohol is mixed with hot water in advance, tea is extracted using the aqueous solution, filtered, and then sweeteners and lemon juice are added as necessary. and other raw materials are added and cooled to obtain tea products.

It is desirable that the tea extraction temperature is in the range of 55 to 95°C. At temperatures lower than 55°C, the bitter and astringent taste derived from tea tends to be somewhat lacking. On the other hand, at high temperatures exceeding 95°C, a significantly large amount of bitter and astringent components are eluted, which may cause problems in terms of flavor.

Alternatively, instead of using hot water used for extraction, tea may be extracted from tea leaves using hot water, and alcohols may be added to the resulting tea solution. In this case, alcohols may be added to the tea solution after extracting tea from tea leaves and filtering, or alcohols may be added when adding other raw materials to the tea solution. In addition, in the production method in which alcohol is added to the extracted tea solution, the alcohol is added before the tea solution is kept cold.

By adding alcohol to the hot water tea solution used in tea extraction as in the above production method, it is believed that the interaction between caffeine and tannins, which causes the cloudiness of tea products, is the main factor. It is presumed that alcohols that have hydroxyl groups and are involved in the hydrogen bonding moieties involved in caffeine and tannins can suppress the formation of complexes between caffeine and tannins, thereby preventing turbidity and precipitation.

Furthermore, it is preferable to add alcohols in advance to the hot water used during extraction in terms of preventing turbidity, improving the flavor retention of tea, and removing alcohol odor.

As the alcohol used in the present invention, aliphatic alcohols having 1 to 8 carbon atoms such as ethyl alcohol, hexyl alcohol, and octyl alcohol, or benzyl alcohol are suitable. Among them, ethyl alcohol is most suitable. Moreover, these may be used alone or in combination.

In addition, the amount of alcohol added is 10% of the solid content in the hot tea liquid.
It is necessary to use 0.2 parts by weight or more in terms of hydroxyl group relative to 0 parts by weight. If the amount added is less than 0.2 parts by weight, turbidity and precipitation cannot be prevented. In addition, when adding alcohols to the hot water during extraction, it is desirable to add 0.5 parts by weight or more of alcohols, and the amount added is based on the amount of solids in the hot tea liquid after extraction. Calculate and determine the amount in advance.

<Effects of the Invention> As described above, in the method for producing tea products of the present invention, turbidity and precipitation of hot tea liquid during cooling storage can be prevented by adding alcohol in the extraction step or blending step. be able to.

In addition, the production method of the present invention does not reduce the content of caffeine and tannins that control the original flavor of tea, does not reduce the original flavor of tea, and also has excellent aroma retention. This is a manufacturing method that prevents turbidity and precipitation.

Next, the present invention will be specifically explained with reference to Examples (Examples 1 to 4). Comparative Example 1> The alcohols listed in Table 1 were added to a black tea solution with a solid content of 100%.
Extract 20g of black tea leaves using a 90°C aqueous solution of 10100O dissolved in an amount of 0.2 parts by weight or 0.5 parts by weight. After that, cool to 30°C and extract 150+20 mesh. Two stages of filters? J' = filtered, and after being cooled at 5°C for 72 hours, flavor, aroma retention, and turbidity were visually evaluated. The results are also shown in Table 1. As a comparative example, a sample without additives was evaluated.

<Example 5> 20 g of black tea leaves were extracted using 1000 ml of 90° C. hot water. Thereafter, it was cooled to 30'C, passed through a 150+20mm filter in two stages, and aged for 5 minutes.
Add alcohol to the black tea solution so that it becomes 0.2 parts by weight relative to 0 parts by weight, and after keeping it cool at 5°C for 72 hours, the flavor, aroma retention, and visual turbidity are determined based on the results in Table 1. It can be seen that this makes it possible to prevent tea from becoming cloudy.

In addition, from the aspect of fragrance retention, an improvement is observed by adding alcohol.

Claims (1)

[Claims] When extracting tea from tea leaves and manufacturing tea products, 0.2 parts by weight of solids in the tea solution in terms of hydroxyl groups.
A method for producing tea products that does not produce turbidity, characterized by adding alcohols in an amount of parts by weight or more to hot water used during extraction in advance, or to a tea solution after extraction.