JP2018134052A - Method for producing methylated catechin-containing tea extract - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a methylated catechin-containing tea extract having a reduced astringent taste.SOLUTION: A tea extract containing (A) methylated catechin, (B) gallate-type catechin and (C) non-gallate-type catechin is treated with tannase.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a methylated catechin-containing tea extract with reduced bitterness and taste obtained by allowing tannase to act on a tea extract containing methylated catechin.

  In recent years, due to factors such as dietary habits, lifestyle, environmental changes and stress, the number of patients diagnosed with allergic diseases has increased, and it is said that one out of every three people suffers from any allergic disease. Yes. Allergic diseases are a major social problem because they significantly reduce the quality of life.

  Various drugs have been developed for the treatment of allergic diseases, but since drugs have side effects, anti-allergic ingredients derived from natural products have been searched. As a result, methylated catechins contained in certain tea leaves are anti-allergic ingredients. (Patent document 1). Methylated catechins are contained in tea leaves of certain varieties such as Benifuuki and Beni-Hare, but if you try to ingest an amount of anti-allergic methylated catechins from these leaves, the bitter taste is extremely bitter. There is a problem that it is strong and difficult to drink.

  A method for extracting methylated catechins from a tea extract with an organic solvent (Patent Document 2), heating tea leaves containing methylated catechins as a method for reducing bitterness and astringency and ingesting a certain amount or more of methylated catechins A method of treating with water vapor (Patent Document 3) is disclosed.

JP 2000-159670 JP 2011-004635 A JP 2015-112023

  The method as described above is disclosed as a method for reducing the bitter astringency and taking a certain amount or more of methylated catechin. However, these methods have at least the following disadvantages. For example, the method of extracting methylated catechin with an organic solvent of Patent Document 2 has a drawback that it is necessary to completely remove the organic solvent from the viewpoint of safety, and that the removal takes time. In addition, the use of an organic solvent is not environmentally preferable, and there is a social problem that consumers do not want contact between the organic solvent and food. In the method of treating tea leaves with heated steam in Patent Document 3, the content of methylated catechin is greatly reduced, so that a large amount of tea must be consumed in order to consume a certain amount or more of methylated catechin. is there.

  Accordingly, an object of the present invention is to provide a methylated catechin-containing tea extract with reduced bitterness and a taste that overcomes the above problems.

  As a result of intensive research to solve the above problems, the present inventor has made methyl extract with a bitter and astringent taste reduced by allowing tannase to act on a tea extract containing methylated catechin to control the composition to a specific catechin composition. The present inventors have found that a catechin-containing tea extract can be obtained and have completed the present invention.

  Tannase is an enzyme that hydrolyzes the ester bond formed between polyphenol and phenolic acid. Epigallocatechin 3-O-gallate, a kind of gallate catechin contained in tea When gallate (hereinafter referred to as EGCg) is used as a substrate, EGCg is an enzyme that decomposes into epigallocatechin (hereinafter referred to as EGC) and gallic acid with less bitter taste. Methylated catechins have been thought to be decomposed by tannase in the same manner as gallate catechins, because the hydroxyl group of the gallate portion of gallate catechins is substituted with a methoxy group. Surprisingly, however, the inventor has found that tannase selectively and preferentially degrades gallate catechins and retains methylated catechins. The reaction selectivity of such tannase has not been reported so far, and by utilizing this reaction selectivity, it is possible to reduce the bitter taste by decomposing gallate catechins while retaining methylated catechins. It is a completely new technology that cannot be recalled from conventional technologies.

  That is, the present invention relates to a method for producing a tea extract and a tea characterized by allowing tannase to act on a tea extract containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin. The present invention provides a method for reducing the bitter and astringent taste of an extract.

  According to the present invention, a methylated catechin-containing tea extract with reduced bitterness and astringency can be produced. In addition, by using the tea extract obtained by the production method of the present invention, it is possible to provide foods and beverages containing methylated catechins with a low bitter taste, in particular, beverages such as containerized tea beverages and powdered tea beverages. it can.

The present invention is described in detail below.
As (A) methylated catechin in the present invention, epigallocatechin 3-O- (3 ″ -O-methyl) gallate (hereinafter referred to as EGCg3 ″ Me) ), Epicatechin 3-O- (3 ”-O-methyl) gallate (hereinafter referred to as ECg3” Me), epigallocatechin 3-O- (4 “-O-methyl) gallate (epigallocatechin 3-O- (4” -O-methyl) gallate, hereinafter referred to as EGCg4 ”Me), epicatechin 3-O- (4” -O-methyl) gallate (epicatechin 3- O- (4 "-O-methyl) gallate, hereinafter referred to as ECg4" Me), gallocatechin 3-O- (3 "-O-methyl) gallate (gallocatechin 3-O- (3" -O-methyl) gallate, GCg3 "Me), catechin 3-O- (3" -O-methyl) gallate (catechin 3-O- (3 "-O-methyl) gallate, hereinafter referred to as Cg3" Me), gallocatechin 3-O -(4 ”-O-methyl) gallate (gallocatechin 3-O- (4” -O-methyl) gallate, hereinafter referred to as GCg4 ”Me), catechin 3-O- (4” -O- This refers to those in which the hydroxyl group of the gallate portion of gallate catechin is substituted with a methoxy group, such as til) gallate (catechin 3-O- (4 ″ -O-methyl) gallate, hereinafter referred to as Cg4 ″ Me). Of these, (A) methylated catechin is the sum of EGCg3 "Me and GCg3" Me. In addition, (B) gallate catechins include epigallocatechin 3-O-gallate (hereinafter referred to as EGCg), epicatechin 3-O-gallate (hereinafter referred to as ECg). ), Gallocatechin 3-O-gallate (hereinafter referred to as GCg), catechin 3-O-gallate (hereinafter referred to as Cg), and (C) non- The gallate catechin refers to epigallocatechin (hereinafter referred to as EGC), epicatechin (hereinafter referred to as EC), gallocatechin (hereinafter referred to as GC), catechin (hereinafter referred to as C). . Further, the total amount of (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin is defined as total catechin.

  The raw tea leaves used in the present invention are tea trees (Camellia sinensis var. Sinensis, Camellia sinensis var. Assamica or hybrids thereof containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin. ) Fresh leaves and stems, or tea leaves made using these as primary ingredients (for example, non-fermented teas such as Sencha, Gyokuro, Kabusecha, Bancha, Kamairi Green Tea, jasmine tea with the scent of flowers transferred to non-fermented tea) Such as flower tea, weakly fermented tea such as white tea, semi-fermented tea such as oolong tea, fermented tea such as black tea, and post-fermented tea such as puar tea). As tea leaves containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin, Benifuuki, Benihore, Benifuji, Kanaya Midori, Yutaka Midori, Ryofu Musashi, Soufu, Okumidori, Yaeho, Surugasuse, Benihikari, Yamakai, Karabe, Yamato Midori, Seishin Soryu, Ooba Soryu, Wushu Daffodil, Seishin Daipan Examples include narcissus narcissus and white leaf plexus narcissus. These tea leaves may be used alone or in combination. Moreover, in order to raise extraction efficiency, you may grind | pulverize, fracture | rupture, and cut | disconnect these beforehand. Among these tea leaves, it is particularly preferable to use tea leaves before fermentation.

  Examples of the method for extracting raw tea leaves in the present invention include known methods such as a batch type extraction method using a kneader or an extraction tank, and a column type extraction method using an extraction tower. The extraction conditions are appropriately selected depending on the type of raw tea leaves, the type of extractor, the flavor, etc., for example, 3 to 50 parts by weight of extraction solvent may be used per 1 part by weight of the raw tea leaves, 4 to 30 parts by weight is preferable in terms of extraction efficiency, production cost, quality, and the like. It is preferable to use water, warm water, or hot water as the extraction solvent because there is no problem in safety. The extraction temperature is not particularly limited, but is preferably 60 to 100 ° C, more preferably 80 to 100 ° C. Although the extraction time depends on the amount of the extraction solvent and the extraction temperature, it is 30 seconds to 6 hours, preferably 3 minutes to 3 hours, and more preferably 4 minutes to 1 hour. During extraction, stirring is performed as necessary, and after the above extraction process, solid-liquid separation is performed by filtration or centrifugation using a filter press combined with a cartridge filter, flannel filter cloth, filter plate, filter paper, filter aid, etc. What is necessary is just to obtain an extract. In the extraction step, an antioxidant may be added in order to suppress oxidation of the tea extract. Examples of the antioxidant include ascorbic acid, erythorbic acid or their metal salts which are recognized as food additives. Moreover, what concentrated the obtained tea extract and melt | dissolved the commercially available tea extract can be utilized as a tea extract in that the starting material is the tea leaf in the first place.

  In the present invention, an enzyme reaction is performed by adding tannase to the tea extract. The tannase used in the present invention refers to a tannin acyl hydrolase (EC 3.1.1.20), which is an enzyme that hydrolyzes an ester bond formed between polyphenol and phenolic acid. When the enzyme reaction substrate is EGCg, tannase hydrolyzes EGCg to produce less bitter astringent EGC and gallic acid. Tannase can be obtained by production of filamentous fungi such as Aspergillus or microorganisms such as yeast or bacteria, and filamentous fungi such as Aspergillus or Penicillium are particularly used. Tannase may be obtained from these filamentous fungi, but industrially commercially available tannase derived from fungi, tannase KT series (Kikkoman Biochemifa Co., Ltd.), Sumiteam TAN (Shin Nihon Chemical Industry Co., Ltd.), tannase (Mitsubishi) It is preferable to use a commercially available enzyme preparation such as Chemical Foods Co., Ltd.

  The amount of tannase added is preferably 0.1 to 100 U, more preferably 0.2 to 50 U, and even more preferably 0.4 to 25 U per gram of tea solid content in the extract. It is desirable to adjust the amount of enzyme to be added as appropriate, but less than 0.1 U per gram of tea solids is not preferable because the reaction time becomes longer, and more than 100 U is preferable because not only gallate catechins but also methylated catechins are decomposed. Absent.

  The reaction temperature of the enzyme reaction with tannase is preferably 0 to 50 ° C, more preferably 5 to 45 ° C, and further preferably 10 to 40 ° C. If it is less than 0 ° C., the reaction time becomes long, which is not preferable, and if it exceeds 50 ° C., the reaction becomes slow due to a decrease in enzyme activity.

  Moreover, it is preferable to adjust the initial pH of the tea extract that causes tannase to act in the range of 4.0 to 6.0. If the initial pH is outside this range, the enzyme activity decreases or the enzyme itself becomes unstable. In addition, since pH falls gradually by the production | generation of a gallic acid during reaction, the progress of reaction can also be estimated by monitoring pH.

  The reaction time ends when the catechin composition of the reaction solution reaches the desired range. Therefore, although not uniquely identifiable, considering work efficiency and component stability, 10 minutes to 12 hours are preferable, 20 minutes to 6 hours are preferable, and 30 minutes to 4 hours are more preferable.

In the method for producing a tea extract of the present invention, a gallate catechin is selectively produced by allowing tannase to act on a tea extract containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin. To control catechin composition. Tannase is allowed to act so that (A) / (B) is 0.19 or more, preferably 0.25 or more, more preferably 0.3 or more, and (A) / ((A) + (B) + (C)) is 0.061. As described above, the bitter and astringent taste can be reduced by allowing tannase to act so that it is preferably 0.07 or more, more preferably 0.08 or more.
The upper limit of (A) / (B) is not particularly limited, but is preferably 0.7 or less in view of manufacturing conditions and the like. Also, (A) / ((A) + (B) + (C)) is preferably 0.08 or less.

  Immediately after the completion of the enzyme reaction, the enzyme is deactivated. The enzyme deactivation treatment can be performed by adjusting pH or heating. When inactivating by adjusting the pH, it is preferable to exceed pH 6.0, and in view of the stability of methylated catechin in the reaction solution, pH 6.0 to 7.5 is more preferable. In the case of inactivation by heating, the heating may be performed under the condition that the enzyme activity stops, and examples include heating at about 60 to 140 ° C. for about 10 seconds to 30 minutes, and at 70 to 95 ° C. It is preferable to carry out for 1 to 10 minutes.

The residual rate of methylated catechin by the enzyme treatment by the tea extract production method of the present invention is preferably 65% or more, more preferably 80% or more, compared with the untreated enzyme reaction product. In addition, the residual rate of gallate catechin is 85% or less, more preferably 70% or less, compared to the enzyme-untreated product. Each remaining rate was calculated from the following formula.
Residual rate of methylated catechin (%) = ((A) methylated catechin / (A) enzyme-treated methylated catechin) × 100
Residual rate of gallate catechin (%) = ((B) gallate catechin / (B) untreated gallate catechin) × 100

  In the production of the tea extract of the present invention, a step of purifying the tannase-treated reaction solution can be provided in order to further reduce the bitter and astringent taste of the tea extract. There are several methods for purification, and these can be appropriately selected and used. For example, known purification treatment means using minerals (active clay, diatomaceous earth, etc.), activated carbon, synthetic adsorption resin, ion exchange resin and the like can be mentioned. In the present invention, it is particularly preferable to purify using an ion exchange resin from the viewpoint of easy purification.

  When purifying with an ion exchange resin, it is preferable to use a weakly acidic cation exchange resin. As the weakly acidic cation exchange resin, Amberlite FPC3500, IRC76, IRC86RF (above, Dow Chemical Company), Diaion WK10, WK11, WK40L (Mitsubishi Chemical Corporation) and the like. Weakly acidic cation exchange resins such as Amberlite FPC3500, IRC76, IRC86RF and Diaion WK40L that have an acrylic polymer as the matrix structure have high affinity with gallate-type catechin and methylated catechin. The bitterness and astringency can be further reduced by removing the gallate catechin. Specifically, the reaction solution is passed through a weakly acidic cation exchange resin so that methylated catechin is adsorbed on the resin and washed with water at room temperature to remove non-gallate catechin, and then 50 ° C to 80 ° C. The methylated catechin can be recovered by passing hot water.

  By treating with the ion exchange resin, it is possible to control the catechin composition by reducing the gallate catechin more selectively. In this case, the resin treatment is performed so that (A) / (B) is 0.25 or more, preferably 0.3 or more, and (A) / ((A) + (B) + (C)) is 0.1 or more, preferably Bitterness can be more effectively reduced by treating the resin so that it becomes 0.2 or more.

The tea extract obtained by the production method of the present invention can be used in the form of an aqueous solution, but if necessary, it may be made into a concentrated liquid, dried solid, powder or the like by a known method. For the concentration, means such as vacuum concentration, reverse osmosis membrane concentration, freeze concentration and the like may be adopted, but considering the flavor side, reverse osmosis membrane concentration and freeze concentration with a small heat load are preferable. The degree of concentration is not particularly limited, but considering the workability when blended into a tea beverage, the tea solid content of the tea extract is preferably 1 to 30%. In the case of sterilization, since the balance of flavor is lost by heating at a high temperature for a long time, heating at a high temperature for a short time (80 to 135 ° C. for about 3 seconds to 30 minutes) is appropriate. Further, the concentrated solution after heating can be prevented from being deteriorated in flavor by refrigeration or freezing. In the case of drying, a generally used method such as a spray drying method or a freeze drying method may be employed.
The content of (A) methylated catechin, (B) gallate catechin, and (C) non-gallate catechin in the tea extract of the present invention may be a predetermined component ratio. Although a high concentration extract can be produced depending on the amount of tea leaves used, the total value of (A) + (B) + (C) per gram of tea solid content is preferably 50 to 900 mg, more preferably 100 to 800 mg. Similarly, (A) methylated catechin is preferably 3 to 90 mg, more preferably 5 to 60 mg.
The sterilization conditions cause thermal isomerization and increase the isomerized GCg3 ″ Me of EGCg3 ″ Me, but there is no influence in the present invention.

  Regardless of its use, the tea extract obtained by the production method of the present invention can be added to beverages and foods to provide beverages and foods with little bitter taste that contain methylated catechins.

  In addition, additives that can be used for various foods as necessary, such as sweeteners, coloring agents, preservatives, thickening stabilizers, antioxidants, emulsifiers, fragrances, pH adjusters, nutrient enhancers, etc. Tea extract can also be used as a preparation by appropriately selecting and mixing.

For example, a tea beverage can be produced by blending the tea extract of the present invention. The tea beverage may be a liquid container-packed tea beverage or a powdered instant tea beverage. The container-packed beverage to which the tea extract of the present invention is added is sterilized at any stage of the production process, and is a metal container, a paper container combined with a metal foil or a plastic film, a molded container mainly composed of polyethylene terephthalate (So-called PET bottles) and bottles can be provided in a normal state. If it can be heat sterilized after filling into a container like a metal can or bottle, it is manufactured by retort sterilization (110-140 ° C., 1 to several tens of minutes), but cannot be retort sterilized like a plastic bottle or paper container Before filling, sterilize at high temperature and short time with a plate heat exchanger (UHT sterilization: 110 to 150 ° C. for 1 to several tens of seconds), cool to a certain temperature, and then fill a pre-sterilized container. You can choose the method of doing. The above-mentioned packaged tea beverages include (A) methylated catechins, (B) gallate catechins, (C) non-gallate catechins with (A) / (B) of 0.19 or more, (A) / ((A) + ( B) + (C)) may be prepared so as to be 0.061 or more. Total value of (A) methylated catechin, (B) gallate catechin, and (C) non-gallate catechin, total catechin, 40-150 mg / 100 mL, (A) methylated catechin concentration 3.5-8.0 mg / 100 mL It is preferable to prepare such that Moreover, it is preferable to adjust pH of this tea drink to 5.5-7.0 in 25 degreeC conversion value.
Furthermore, in the case of an instant powder tea beverage, the tea extract obtained by drying the tea extract of the present invention by the above method can be used as it is as an instant tea beverage. Moreover, you may make the powdered tea preparation liquid which added the liquid tea extract by the well-known method.

  The following examples further illustrate the present invention. However, the present invention is not limited to this.

[Examination example 1]
200 g of green tea leaves (variety Benifuuki) was added to 3000 g of ion-exchanged water at 85 ° C, extracted with stirring for 30 minutes, and then solid-liquid separation was performed using production filter paper (No.28, Advantech Co., Ltd.) to extract 2162 g A solution (pH 5.34, Brix 3.24%) was obtained. The extract was concentrated using a rotary evaporator and then freeze-dried to obtain 53.18 g of a benifuki extract.
From the resulting Benifuuki extract, prepare a Benafuuki extract with a solids concentration of 25 mg / mL, add 2 mL of a commercially available tannase solution to 8 mL of this Bukifuuki extract, and add pH 5.4 at the specified temperature (5, 20, 35 ° C). The enzyme reaction was carried out for a predetermined time (0, 30, 60, 90, 120 minutes). As a commercially available tannase, Sumiteam TAN (Shin Nihon Chemical Industry Co., Ltd.) was used. After the enzyme reaction, the reaction solution was heated in a boiling water bath for 5 minutes to inactivate the enzyme, and the component composition of the obtained tea extract was quantified by HPLC analysis.

(HPLC analysis method)
HPLC analysis was performed under the following conditions. Standard substances for quantification include methylated catechins (EGCg3 ”Me and GCg3” Me, Nagara Science Co., Ltd.), gallate catechins (EGCg, ECg, GCg, Cg, Mitsui Norin Co., Ltd.), non-gallate catechins ( EGC, EC, GC, C, Mitsui Norin Co., Ltd., gallic acid (Kanto Chemical Co., Ltd.), caffeine (Kanto Chemical Co., Ltd.) were used.
Equipment: Alliance HPLC system (Waters)
Column: Poroshell 120 EC-C18 (4.6 × 100mm, particle size 2.7μm, manufactured by Agilent)
Column temperature: 40 ° C
Mobile phase: Liquid A 0.05% phosphoric acid water / acetonitrile = 1000/25 (volume ratio), liquid B methanol gradient program: 0 to 1 minute, B 0% to 1 to 11 minutes, B 0 to 33% → 11 to 11.25 Minutes, B 33-95% → 11.25-13.25 minutes, B 95% → 13.25-13.5 minutes, B 95-0% → 13.5-15.5 minutes, B 0%
Flow rate: 1.5mL / min
Detection: UV 230nm (catechins), 275nm (gallic acid, caffeine)

  In addition, the tea extract was diluted with ion-exchanged water so that the methylated catechin concentration was 6.8 mg / 100 mL, and the untreated product was subjected to sensory evaluation with 5 panelists and subjected to an average treatment for comparison. The evaluation criteria are as follows.

(Evaluation criteria for bitterness and astringency)
Evaluation points: 4 (reduced considerably), 3 (reduced), 2 (not reduced) 1 (increased)
Evaluation: The average evaluation score of 5 people was 3.4 or more, 2.7, 2.7 to 3.3 was ○, 1.7 to 2.6 was Δ, and 1.6 or less was ×.

  From Table 1, the ratio of (A) methylated catechins to (B) gallate catechins, and the ratio of (A) methylated catechins to total catechins (total of (A) + (B) + (C)) By allowing tannase to act on the tea extract to be constant, it was confirmed that a tea extract with reduced bitterness and astringency was obtained while retaining 65% or more of methylated catechin. It was confirmed that the reaction temperature of the enzyme reaction with tannase is more preferably 20 to 35 ° C. from the viewpoint of the enzyme treatment time.

[Examination example 2]
From the freeze-dried Benifuki extract before the enzyme treatment obtained in Study Example 1, a Benifuki extract with a tea solid concentration of 25 mg / mL was prepared, and a predetermined pH (4.5, 5.5, 6.5). 2 mL of a commercially available tannase solution was added to 8 mL of this Fuuki extract, and an enzyme reaction was performed at 25 ° C. for a predetermined time (0, 30, 60, 90, 120 minutes). As a commercially available tannase, Sumiteam TAN (Shin Nihon Chemical Industry Co., Ltd.) was used. After the enzyme reaction, the reaction solution was heated in a boiling water bath for 5 minutes to deactivate the enzyme to obtain a tea extract. The obtained tea extract was subjected to HPLC analysis and sensory evaluation in the same manner as in Examination Example 1.

  From Table 2, it was confirmed that in the tannase treatment, by adjusting the initial pH to the range of 4.0 to 6.0, it was possible to obtain a methylated catechin-rich tea extract with reduced gallate catechins.

10 g of green tea leaves (variety Benifuuki) was added to 150 g of ion-exchanged water at 90 ° C, stirred and extracted for 30 minutes, and then solid-liquid separation was performed using production filter paper (No.28, Advantech Co., Ltd.). The liquor was diluted to 2.66% tea solids to obtain a benifuuki extract. 2 mL of enzyme solution (Tannase KTFH (Kikkoman Biochemifa Co., Ltd.) 50 mg / 5 mL) was added to 78 mL of this Fuukiuki extract, and the enzyme reaction was performed at pH 5.4 and 5 ° C. for 100 minutes. After the enzyme reaction, the reaction solution was heated in a boiling water bath for 5 minutes to inactivate the enzyme to obtain a reaction solution serving as Invention Example 14.
40 mL of this reaction solution was passed through Amberlite FPC3500 (20 mm × 95 mm, 30 mL, Dow Chemical) at 25 ° C., and then 140 mL of ion-exchanged water was passed at 25 ° C. (Comparative Example 12). Subsequently, 180 mL of ion-exchanged water was passed at 70 ° C. to recover the tea extract as Invention Example 15. The obtained tea extract was subjected to HPLC analysis and sensory evaluation in the same manner as in Examination Example 1.

  From the results in Table 3, it was confirmed that by further purifying the tea extract after tannase treatment, a non-gallate catechin was removed and a tea extract rich in methylated catechin was obtained.

[Production Example 1] Instant powdered beverage Dextrin was added to the tea extract of Invention Example 6, powdered after lyophilization, and vitamin C was blended to prepare a powdered beverage. The formulation is shown below.
1. Dextrin 74.0% by weight
2. Invention Example 15 23.0% by weight
3. Vitamin C 3.0% by weight

[Production Example 2] Container-packed tea beverage For Invention Example 3 obtained in Study Example 1, untreated product 1 tea extract (freeze-dried product), ascorbic acid concentration 30 mg / 100 mL, total catechin ((A) + ( B) + (C)) The solution was diluted with water to a concentration of 70 mg / 100 mL. Further, sodium bicarbonate was added so that the pH was 6.8 to prepare a preparation solution. The prepared liquid was sterilized by retort (121 ° C., 10 minutes) to obtain a packaged tea beverage.
As a result of sensory evaluation in the same manner as in Examination Example 1, a packaged tea beverage with reduced bitterness and astringency was obtained as compared with the untreated product.

  The method for producing a tea extract of the present invention can reduce bitterness and astringent taste by selectively decomposing gallate catechins while retaining methylated catechins contained in the tea extract. It has industrial applicability in that it can be used to provide a methylated catechin-containing food and drink with little bitterness.

Claims (9)

  A method for producing a tea extract, characterized in that tannase is allowed to act on a tea extract containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin.   The tannase is caused to act so that (A) / (B) is 0.19 or more and (A) / ((A) + (B) + (C)) is 0.061 or more. Production method of tea extract.   The method for producing a tea extract according to claim 1 or 2, wherein the extract is treated with a weakly acidic cation exchange resin after allowing tannase to act.   A method for reducing the bitter and astringent taste of a tea extract, characterized by allowing tannase to act on a tea extract containing (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin.   The tannase is caused to act so that (A) / (B) is 0.19 or more and (A) / ((A) + (B) + (C)) is 0.061 or more. A method for reducing the bitter and astringent taste of tea extracts.   6. The method for reducing bitterness and astringency of a tea extract according to claim 4 or 5, wherein the extract is treated with a weakly acidic cation exchange resin after allowing tannase to act.   (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin, (A) / (B) is 0.19 or more, and (A) / ((A) + (B) + (C)) is a tea extract and its dried product characterized by 0.061 or more.   It is a manufacturing method of the tea drink which mix | blends the tea extract of Claim 7, Comprising: (A) / (B) is 0.19 or more and (A) / ((A) + (B) + (C)) A tea beverage production method characterized by satisfying 0.061 or more. (A) methylated catechin, (B) gallate catechin and (C) non-gallate catechin, (A) / (B) is 0.19 or more, and (A) / ((A) + (B) + (C)) is 0.061 or more, a packaged tea beverage or a powdered tea beverage.