JP4739036B2 - Process for producing a processed tea extraction product with improved flavor - Google Patents

Description

  The present invention relates to a method for producing a tea extraction processed product that has reduced bitter astringency and astringent taste peculiar to catechins and has an improved flavor that does not have a sour taste or a gummy taste.

  Tea has long been popular as a favorite beverage, but recently, canned beverages filled in cans or plastic bottles, etc., that can be easily consumed have been provided for more than a decade ago, and consumers can become sweet. As a result, the production volume has been increasing steadily. On the other hand, tea has recently attracted attention in terms of its functionality and has been actively studied, and physiological effects such as suppression of human body fat accumulation by catechins (Non-patent Document 1) have been reported. However, when a large amount of catechins were added as a container-packed beverage, the bitter astringency and astringent taste became strong, and the disadvantage of being very difficult to take in flavor was observed.

  The main components of non-polymer catechins in tea are free catechin (epicatechin, epigallocatechin, catechin, gallocatechin) and ester catechin (epicatechin gallate, epigallocatechin gallate, catechin gallate, gallocatechin gallate) Among them, it is reported that free catechins have high astringency and astringency taste thresholds, and ester catechins have low astringency and astringency taste thresholds (Patent Document 1).

  On the other hand, it is known that tannase can be used for clarifying tea beverages, but it is an enzyme that acts on an ester bond between catechin and gallic acid to hydrolyze it into catechin and gallic acid. Cream-down (precipitation) in tea beverages is known to occur when gallate-type catechin (synonymous with ester-type catechin) and caffeine form a complex. A method has been reported in which gallate-type catechins are decomposed into non-gallate-type catechins (synonymous with free-type catechins) to make complex formation with caffeine difficult (Non-patent Document 2).

  In addition, by applying the tannase treatment to the tea-making process of green tea and treating epicatechin gallate and epigallocatechin gallate with strong bitter taste contained in tea leaves with tannase, epicatechin having refreshing bitterness with gallic acid And a method for decomposing it into epigallocatechin is disclosed (Patent Document 2).

  On the other hand, as described above, attention is paid to the functionality of catechins in container-packed beverages, and it is required to add a large amount of catechins. However, a tea beverage containing a high concentration of catechins should be treated with tannase. Discloses a method for reducing the bitter and astringent taste of catechins (Patent Document 3).

  However, in the method of Patent Document 3, ester catechin is decomposed into free catechin and gallic acid by treating catechins with tannase, and the astringency and astringent taste derived from ester catechins are reduced. The sour and savory tastes that originate from it occur, and it cannot be said that the flavor is still satisfactory.

  On the other hand, by controlling the degradation of non-polymer catechins by tannase and controlling the gallate content in catechins within the range of 40 to 60% by weight, the astringency and astringency derived from ester-type catechins A method for reducing the taste and improving the flavor (Patent Document 4) is disclosed.

JP-A-6-343389 JP-A-5-308901 JP 2005-130809 A JP 2004-321105 A Journal of Oleo Science Vol. 50 (2001), no. 9 p717-728 "Food and Development" 32 (12), 1997, p14-16

  Patent Document 4 discloses a green tea extract with an improved flavor in which the percentage of gallate body in non-polymer catechins is 40 to 60% by weight, but also in this method, free gallic is also obtained by tannase treatment. The problem of acid generation and the sour taste associated with the gallic acid-derived taste remained unresolved. In addition, the tannase treatment of tea extract reported so far is carried out in an aqueous solution having a non-polymer catechin concentration of less than 1% by weight, which is considered to be problematic in terms of production cost and production efficiency. .

  Therefore, an object of the present invention is to have an excellent flavor that does not have a taste that makes a bitter astringent taste, astringent taste, sour taste, gummy taste, etc. even in a beverage containing a high concentration non-polymer catechin from a tea extract. It is providing the method of manufacturing a tea extract efficiently.

  When the present inventors diligently studied to improve the flavor of the green tea extract, the content of gallate-type catechins with respect to the total amount of non-polymer catechins is adjusted to 0 to 40% by treating the tea extract with tannase. By reducing the astringent taste and astringent taste derived from ester-type catechins, and further treating the tea extract treated with tannase with an ion exchange resin, the free gallic acid is efficiently removed, and the sourness peculiar to gallic acid It has been found that a tea extract having no savory taste can be obtained, and the present invention has been completed.

Moreover, the non-polymer catechins-containing aqueous solution with reduced bitterness, astringency and taste can be efficiently produced even in mass production by performing tannase treatment in a state of containing 1 to 10% by weight as the concentration of non-polymer catechins. It was found that can be manufactured.
Thus, the present invention provides a method for producing a tea extraction processed product, characterized in that after the tea extract is tannase treated, the released gallic acid is removed by contact with an anion exchange resin.

Further, in the present invention, (a) the gallate content in the non-polymer catechins is 0 to 40% by weight in the tea extraction processed product, and (b) gallic acid / (non-polymer catechins + gallic acid) Is 0-0.15
The method for producing a tea extraction processed product according to claim 1 is provided.

Furthermore, in this invention, the manufacturing method of the tea extraction processed material as described in the above, wherein the concentration of non-polymer catechins in the tea extract is 1 to 10% by weight.
Further, the present invention is a tea extraction treatment product obtained by tannase treatment of a tea extract and then removing gallic acid released by contact with an anion exchange resin,
In the tea extraction processed product
(A) The gallate content in the non-polymer catechins is 0 to 8.5% by weight, and
(B) Gallic acid / (non-polymer catechins + gallic acid) is 0 to 0.15
A tea extraction processed product is provided.
The present invention also includes foods and drinks containing the tea extraction processed product.

  According to the present invention, the bitter and astringent taste is reduced by reducing the content of gallate-type catechins in the non-polymerized catechin by tannase treatment, and the sourness and gummy taste is reduced by reducing the content of gallic acid released by tannase treatment. Can be removed, and a method for producing a tea extract with good flavor can be provided. In addition, performing tannase treatment at a higher concentration than conventional methods is advantageous from the viewpoint of production efficiency and manufacturing cost.

  Non-polymer catechins in the present invention are non-epimeric catechins such as catechin, gallocatechin, catechin gallate and gallocatechin gallate and epi-catechins such as epicatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate Is a collective term for eight types. The gallate-type catechins (synonymous with ester-type catechins) of the present invention are generic names of gallate-type catechins such as catechin gallate, gallocatechin gallate, epigallocatechin gallate, and epicatechin gallate among the above catechins. Means. The gallate body ratio in the present invention is a 100 fraction of the weight sum of the four gallate catechins to the weight sum of the eight non-polymer catechins.

  The tea leaves used in the present invention include sencha, bancha, gyokuro, tencha, tea in a pot, etc. made from tea leaves obtained from tea (Camellia sinensis (L) O. Kuntze), which is an evergreen tree of the camellia family. Examples include green tea that is non-fermented tea; oolong tea, black tea, black tea, and the like that are made from the tea leaves through a semi-fermentation or fermentation process.

  Examples of the tea extract of the present invention include the tea leaf extract described above or a concentrate thereof. As an extract of tea leaves, the above-mentioned tea leaves are stirred with water or a water-soluble organic solvent, for example, at 10 to 100 ° C. for 3 minutes to 2 hours, or subjected to appropriate separation means such as centrifugation. The extract obtained by separating the extract liquid can be exemplified, and the concentrate of the tea leaf extract can be exemplified by a concentrate obtained by concentrating the tea leaf extract with an organic solvent, vacuum concentration, membrane concentration or the like. In addition, commercially available “Polyphenone” (Mitsui Norin Co., Ltd.), “Theafranc” (Itoen Co., Ltd.), “Sanphenon” (Taiyo Kagaku Co., Ltd.), “Sun Oolong” (Suntory Ltd.), “PF-” Catechin powders such as “TP” (Pharma Foods Co., Ltd.) and “Polyphenone HG” (Tokyo Food Techno Co., Ltd.) can be dissolved in water or a water-soluble organic solvent to obtain a tea extract. The concentration of non-polymer catechins in the tea extract is 1 to 10%, preferably 1 to 5%, more preferably 1 to 3%. If the concentration of non-polymer catechins exceeds 10%, the activity of tannase decreases due to the osmotic pressure of non-polymer catechins, and in order to obtain the same gallate body rate, it is necessary to increase the amount of tannase, which is inefficient. Further, when the concentration of non-polymer catechins is less than 1%, the amount of liquid to be processed increases, resulting in a decrease in production efficiency and an increase in manufacturing cost. By performing tannase treatment within this non-polymer catechin concentration range, work can be efficiently performed on an industrial scale.

  Any tannase used in the present invention can be used as long as it has an activity of decomposing gallate ester bonds of non-polymer catechins, and specifically, Aspergillus, Penicillium, Rhizopus, etc. A tannase obtained by culturing a tannase-producing bacterium can be used. Of these, those derived from Aspergillus oryzae are particularly preferred.

  The amount of tannase added to the tea extract is about 0.02 to about 2.0 Units, preferably about 0.05 to about 0.4 Units, per 1 mg of non-polymer catechins. Here, 1 Unit is defined as the amount of enzyme that hydrolyzes the ester bond contained in tannic acid 1 micromole per minute in 30 ° C. water. As tannase treatment conditions, the pH of the aqueous solution is suitably 4.0 to 6.0, preferably 4.5 to 5.5, and the temperature of the aqueous solution is 30 to 45 ° C., preferably 35 to It is appropriate to carry out at 40 ° C. After the tannase treatment, the temperature is raised to 70 to 90 ° C. as soon as possible to deactivate the tannase and stop the reaction.

  The ester type catechin content relative to the total amount of non-polymer catechins can be adjusted to the target by controlling the tannase treatment time, treatment temperature, treatment concentration, and the reaction behavior depends on the pH change of the reaction solution. Judgment can be made.

  By the above method, the ester type catechin content with respect to the total amount of non-polymer catechin in the tea extract is adjusted to 0 to 40% by weight. By adjusting the ester-type catechin content to 0 to 40% by weight relative to the total amount of non-polymer catechins, bitterness and astringency can be reduced. When the ester type catechin content exceeds 40% by weight, the bitter and astringent taste and the astringent taste are strongly felt, which is not preferable.

  By tannase treatment, ester-type catechin is decomposed and gallic acid is released. This gallic acid has a sour taste. In the present invention, free gallic acid is removed by bringing the catechins-containing aqueous solution after tannase treatment into contact with an anion exchange resin. The anion exchange resin to be used is not particularly limited, and a commercially available anion exchange resin can be used.

  Usable anion exchange resins include, for example, Diaion SA-10A, SA-11A, SA-20A, SA-21A (above, manufactured by Mitsubishi Kasei Co., Ltd.), Amberlite IRA as strongly basic ion exchange resins. -400, IRA-410, IR-45 (above Rohm & Haas), Dowex AG-1, 21K, 2, 3, AG-4 (above The Dow Chemical), and weak base Examples of the anionic ion exchange resin treatment are Diaion WA20, WA21, WA30 (above, manufactured by Mitsubishi Kasei), Amberlite IRA-93ZU, IRA94S, IRA-94S-HG (above, manufactured by Rohm and Haas) , Dowex S40285 (The Dow Chemical Co., Ltd.) and the like.

  As the ion exchange resin treatment, either a batch method or a column method can be adopted, but the column method can be preferably adopted from the viewpoint of workability. As a method of processing in the column system, for example, a tea extract liquid 10 to 1000 times the resin is passed at a flow rate of SV = 1 to 100 through a column filled with the ion exchange resin as described above, and gallic By adsorbing the acid and collecting the non-adsorbed portion, the tea extraction processed product with reduced bitterness and astringency of the present invention can be obtained. In the present invention, the concentration of non-polymer catechins in the tannase treatment liquid, the brix of the tannase treatment liquid, the amount of ion exchange resin used, the flow rate through the ion exchange resin, etc. are adjusted, and the free in the tea extraction treatment product Control the content of gallic acid as gallic acid / (non-polymer catechins + gallic acid), 0 to 0.15, preferably 0.02 to 0.15, more preferably 0.05 to 0.15. It is possible to obtain a tea extraction processed product with reduced sourness and gummy taste. When the content of free gallic acid in the tea extraction product exceeds 0.15 as gallic acid / (non-polymer catechins + gallic acid), the sour taste peculiar to gallic acid can be felt. It is not preferable. The gallic acid / (non-polymer catechins + gallic acid) is preferably as small as possible, but the required amount of ion exchange resin becomes too large, which is not practical industrially.

The tea extraction product of the present invention obtained by the above-described method can be used as it is in the form of an aqueous solution as it is, but if desired, an appropriate concentration means can be adopted to form a concentrate. Further, if desired, the aqueous solution may be dried by adding appropriate drying means such as spray drying, vacuum drying, freeze drying or the like without adding or adding excipients such as dextrin, modified starch, cyclodextrin, gum arabic and the like. It can also be made into a powder form.

Thus, according to the present invention, food / beverage products, cosmetics, health / hygiene / pharmaceuticals, etc. containing non-polymer catechins with reduced bitter and astringent taste and reduced astringency and no sour / paste taste are provided. Can do. Examples of these include, for example, beverages such as tea beverages, sports beverages, carbonated beverages, fruit juice beverages, milk beverages, alcoholic beverages; , Chocolate, bread, coffee, tea and other favorite products; foods and drinks with various functionalities by adding non-polymer catechins obtained by the production method of the present invention to various snacks Goods can be provided.
Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

Example 1
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate content: 50%) 5.94% by weight aqueous solution of 2,000 g (2.0% non-polymer catechins, After heating to 35 ° C. at a gallate ratio of 50%, pH 5.0), 1.2 g of tannase (5000 Unit / g manufactured by Kikkoman) was added (0.15 Unit for 1 mg of non-polymer catechins). After standing still at the same temperature for 30 minutes, the temperature was raised to 80 ° C. to deactivate tannase and stop the reaction (pH 4.2, non-polymer catechins 1.74%, gallate body ratio 8.5 %, Gallic acid 0.49%). Thereafter, the pH was adjusted to 5.0 with sodium bicarbonate to obtain 2000 g of an aqueous solution containing catechins (reference product 1: 1.74% of non-polymer catechins, 8.5% gallate body ratio, 0.49% gallic acid content) Gallic acid / (gallic acid + non-polymer catechins) = 0.220).

  1050 g of the reference product 1 was passed through 35 ml of an anion exchange resin (Diaion SA10A, manufactured by Mitsubishi Chemical Corporation) to obtain 980 g of a passing solution (present product 1: 1.71% non-polymer catechins, gallate) Body ratio 8.5%, gallic acid content 0.13%, gallic acid / (gallic acid + non-polymer catechins) = 0.071).

Method for measuring catechins After diluting a sample with distilled water, the sample is filtered with a filter (0.45 μm), and using a high-performance liquid chromatography manufactured by Waters (Waters 2695 type separation module, Waters 2996 photodiode array module) A chromatographic packed column L-column TM ODS (4.6 mmφ × 250 mm: manufactured by Chemical Substances Research Institute) is attached, and the gradient is carried out at a column temperature of 35 ° C. The aqueous solution containing 1 mol / liter and B solution were acetonitrile solutions containing acetic acid at 0.1 mol / liter, the sample injection volume was 10 μL, and the UV detection wavelength was 280 nm.

Example 2
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate content: 50%) 5.94% by weight aqueous solution of 2,000 g (2.0% non-polymer catechins, After heating to 35 ° C. at a gallate ratio of 50%, pH 5.0), 1.2 g of tannase (5000 Unit / g manufactured by Kikkoman) was added (0.15 Unit for 1 mg of non-polymer catechins). After standing at the same temperature for 120 minutes, the temperature was raised to 80 ° C. to deactivate tannase and stop the reaction (pH 4.1, non-polymer catechins 1.72%, gallate body ratio 1.5 %, Gallic acid 0.60%). Thereafter, the pH was adjusted to 5.0 with sodium bicarbonate to obtain 2000 g of an aqueous solution containing catechins (Reference 2: 1.72% non-polymer catechins, 1.5% gallate body ratio, 0.60% gallic acid, Gallic acid / (gallic acid + non-polymer catechins) = 0.259).

  1050 g of the reference product 2 was passed through 35 ml of an anion exchange resin (Diaion SA10A, manufactured by Mitsubishi Chemical Corporation) to obtain 980 g of a passing solution (present product 2: 1.72% non-polymer catechins, gallate) Body ratio 1.5%, gallic acid content 0.24%, gallic acid / (gallic acid + non-polymer catechins) = 0.122).

Comparative Example 1
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate content: 50%) 5.94% by weight of 1,000 g aqueous solution (2.0% non-polymer catechins, Galate body ratio 50.0%, pH 5.0), heated to 80 ° C. (Comparative product 1: non-polymer catechins 2.0%, gallate body ratio 50.0%, pH 5.0, gallic acid content 0 0.05%, gallic acid / (gallic acid + non-polymer catechins) = 0.024).

Comparative Example 2
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate content: 50%) 5.94% by weight aqueous solution of 2,000 g (2.0% non-polymer catechins, After heating to 35 ° C. at a gallate ratio of 50%, pH 5.0), 0.12 g of tannase (5000 Unit / g manufactured by Kikkoman Corporation) was added (0.015 Unit for 1 mg of non-polymer catechins). After standing at the same temperature for 30 minutes, the temperature was raised to 80 ° C. to deactivate tannase and stop the reaction (pH 4.8, non-polymer catechins 2.0%, gallate body ratio 44.2). %, Gallic acid 0.09%). Thereafter, the pH was adjusted to 5.0 with sodium bicarbonate to obtain 2000 g of an aqueous solution containing catechins (Comparative product 2: 2.0% non-polymer catechins, 44.2% gallate content, 0.09% gallic acid, Gallic acid / (gallic acid + non-polymer catechins) = 0.043).

Example 3
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate body ratio 50%) 23.74% 500 g of aqueous solution (non-polymer catechins 8.0%, gallate body ratio) After heating to 35 ° C., 2.4 g of tannase (5000 Unit / g manufactured by Kikkoman) was added (0.3 Unit for 1 mg of non-polymer catechins). After standing at the same temperature for 180 minutes, the temperature was raised to 80 ° C. to deactivate tannase and stop the reaction (pH 4.2, non-polymer catechins 7.2%, gallate body ratio 4.9). %, Gallic acid 1.92%). Thereafter, the pH was adjusted to 5.0 with sodium bicarbonate to obtain 500 g of a catechins-containing aqueous solution (reference product 3: non-polymer catechins 7.2%, gallate ratio 4.9%, gallic acid 1.92%). .

  260 g of the reference product 3 was passed through 35 ml of an anion exchange resin (Diaion SA10A, manufactured by Mitsubishi Chemical Corporation) to obtain 245 g of a passing solution (present product 3: non-polymer catechins 7.2%, gallate). Body ratio 4.9%, gallic acid content 0.58%, gallic acid / (gallic acid + non-polymer catechins) = 0.075).

Comparative Example 3
Polyphenone HG (manufactured by Tokyo Food Techno: non-polymer catechin content: 33.7% by weight, gallate body ratio: 50%) 37.1% aqueous solution 320 g was prepared (non-polymer catechins: 12.5%, gallate body ratio After heating to 35 ° C., 2.4 g of tannase (5000 Unit / g manufactured by Kikkoman) was added (0.3 Unit for 1 mg of non-polymer catechins). When the mixture was kept standing at the same temperature for 120 minutes, the gallate body ratio after the reaction was 42.9%. Then, furthermore, it was kept still at the same temperature for 60 minutes, but the gallate body ratio was reduced only to 40.9%, and when the concentration of non-polymer catechins in the aqueous solution exceeded 10% by weight, It was shown that the activity of tannase was not fully exhibited.

  (A) gallate content in non-polymer catechins of catechins-containing aqueous solutions of the present invention products 1 to 3, reference products 1 and 2, and comparative products 1 and 2, and (b) gallic acid / (non-polymer catechins The value of (+ gallic acid) is shown in Table 1.

Example 4 (example blended in green tea beverage)
After adding 2000 g of 60 ° C. ion exchange water to 100 g of sencha and leaving it to stand for 10 minutes with occasional stirring, the tea leaves were separated with a 40 mesh wire mesh. The tea leaf residue was washed with 1000 g of ion-exchanged water. After suction filtration using 2 filter papers, 4 g of sodium L-ascorbate and 0.2 g of sodium bicarbonate were added to the filtrate, and the concentration was adjusted to 500 ppm as a non-polymer catechin concentration in ion-exchanged water (total amount of about 10 kg). The green tea beverages of the present invention products 1 to 3, the reference products 1 and 2, and the comparative products 1 and 2 were blended so that the concentration of non-polymer catechins was 1000 ppm, respectively, and 138 ° C., 30 seconds UHT Sterilized, cooled to 88 ° C., filled into a PET bottle, and further water cooled to 30 ° C. Each plastic bottle drink was stored at room temperature for 2 weeks and then subjected to sensory evaluation by 20 well-trained panelists. The sensory evaluation results are bitter astringent / astringent taste, sour / egu taste, and comprehensive evaluation, each with a perfect score of 20 points, very preferable: 17 to 20 points, slightly good: 14 to 17 points, normal: 11 to 14 points Slightly inferior: 8 to 11 points, inferior: Scored on an evaluation standard of 8 points or less, and the average score of 20 panelists is shown in Table 2.

As shown in Table 2, the green tea beverage to which the product of the present invention is added contains non-polymer catechins at a high concentration of 1000 ppm. I couldn't feel it at all. On the other hand, green tea beverages to which comparative product 1 (untreated tannase treatment: gallate body rate 50%) and comparative product 2 (tannase treated but gallate body rate 44.2%) have a strong bitter taste and astringent taste. , Felt noticeable. In addition, the green tea beverage to which the reference product 1 and the reference product 2 to which the tannase treatment was applied and the gallate rate was 40% or less but the anion exchange resin treatment was not performed strongly felt sourness and gummy taste.

Claims (4)

  A method for producing a tea extract-treated product, comprising: treating a tea extract with tannase, and then removing liberated gallic acid by contacting with an anion exchange resin. The gallate content in (a) non-polymer catechins in the tea extraction product is 0 to 40% by weight, and (b) gallic acid / (non-polymer catechins + gallic acid) is 0 to 0.00. 15
The method for producing a tea extraction processed product according to claim 1.   The method for producing a tea extraction processed product according to any one of claims 1 and 2, wherein the concentration of the non-polymer catechins in the tea extract is 1 to 10% by weight. After the tea extract is tannase-treated, it is a tea extraction treatment product obtained by removing free gallic acid in contact with an anion exchange resin,
In the tea extraction processed product
(A) The gallate content in the non-polymer catechins is 0 to 8.5% by weight, and
(B) Gallic acid / (non-polymer catechins + gallic acid) is 0 to 0.15
Tea extract-treated product is.