JP2011015614A - Method for producing purified tea extract - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a purified tea extract having good flavor reduced in a harsh taste by removing the harsh taste from the tea extract.SOLUTION: The method for producing the purified tea extract includes: (1) a step for adding ethylenediamine tetraacetic acid or a salt thereof to the tea extract, (2) a step for bringing the tea extract mixture to contact with a synthetic adsorbent, (3) a step for eluting ethylenediamine tetraacetic acid or the salt thereof with water or an aqueous organic solvent solution having <5 mass% organic solvent concentration, and (4) a step for eluting non-polymeric catechins with an aqueous organic solvent solution with 10-70 mass% organic solvent concentration, wherein the steps are sequentially carried out.

Description

  The present invention relates to a method for producing a purified tea extract, a method for removing the taste of a tea extract, and a packaged beverage using the purified tea extract.

As an effect of the catechins contained in the tea extract, a cholesterol elevation suppressing action, an amylase activity inhibiting action and the like have been reported (Patent Documents 1 and 2). In order to express such physiological effects, it is necessary to drink 4 to 5 cups of tea per day for an adult. Therefore, in order to ingest a large amount of catechins more easily, a high concentration of catechins There is known a method of adding sucrose to a food or drink such as a beverage in a dissolved state.
However, when catechins are blended at a high concentration, catechins not only exhibit bitterness and astringency, but other ingredients contained in the tea extract may cause bitterness, astringency, astringency, egg taste, miscellaneous taste, etc. It will be strengthened.

  Examples of methods for reducing such unpleasant bitterness and improving the flavor of tea extract include caffeine and polyphenols by the adsorption method (Patent Documents 3-6) and extraction methods (Patent Documents 7 and 8). A method has been reported to remove foreign impurities.

On the other hand, ethylenediaminetetraacetic acid is a chelating agent used in various applications, and is used, for example, as an antioxidant for canned and bottled foods. In addition, a method of adding ethylenediaminetetraacetic acid to mineral water and excreting harmful heavy metals in mineral water (Patent Document 9); adding brown ethylenediaminetetraacetic acid to a green tea extract and browning a packaged beverage containing catechins at a high concentration A method of suppressing change (Patent Document 10); a method of adding aminopolycarboxylic acid to tea beverage to suppress the occurrence of floc (Patent Document 11) has been reported.
However, it has not been known so far to use ethylenediaminetetraacetic acid or a salt thereof for improving the flavor of tea extract.

JP-A-60-156614 JP-A-3-133828 JP-A-5-153910 JP-A-8-109178 JP 2002-335911 A JP 2006-36645 A JP-A-1-289447 JP 59-219384 A JP 2005-348626 A Japanese Patent Laid-Open No. 2006-166771 JP 2007-325569 A

According to the conventional method, the unpleasant bitterness or astringency of the tea extract is improved, but it is difficult to say that the taste is sufficiently reduced. The taste of tea extract is different from that of bitter taste, and it is generally thought that it is mainly derived from gallic acid and oxalic acid contained in tea extract.For example, as a technology to remove gallic acid, Japanese Laid-Open Patent Publication No. 2008-220202 proposes to perform tannase treatment and anion exchange resin treatment in combination.
However, the inventors' research has revealed that there is an unpleasant and unpleasant taste that is derived from gallic acid, etc. The taste of the tea extract, particularly the remaining taste, may greatly impair the commercial value depending on the type of food or drink to which the catechins are blended at a high concentration.

  Therefore, the present invention relates to providing a method for producing a refined tea extract having a reduced flavor and a reduced flavor of the tea extract.

As a result of studying the taste remaining after the tea extract, the present inventor has found that there is a cause of the taste in the coexistence state of epicatechin gallate and iron in the tea extract. In other words, epicatechin gallate formed a complex with iron in the tea extract, and thus it had an unpleasant taste and a crispy taste that was awkward. As a result of investigations by the present inventors, it was found that this taste can be reduced by adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract mixture. However, it was newly found that the treatment produces an acidity that was not felt with the original tea extract.
Therefore, as a result of further investigation, the present inventors contacted the tea extract after addition of ethylenediaminetetraacetic acid or its salt with a synthetic adsorbent, and eluted and removed ethylenediaminetetraacetic acid or its salt with water. It was found that a purified tea extract with a reduced taste was obtained without feeling sour.

That is, the present invention includes the following steps (1) to (4):
(1) adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract;
(2) contacting the tea extract mixture with a synthetic adsorbent;
(3) a step of eluting ethylenediaminetetraacetic acid or a salt thereof with water or an organic solvent aqueous solution having an organic solvent concentration of less than 5% by mass;
(4) a step of eluting non-polymer catechins with an organic solvent aqueous solution having an organic solvent concentration of 10 to 70% by mass;
A method for producing a purified tea extract, which is sequentially performed.

Moreover, the present invention includes the following steps (1) to (4):
(1) adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract;
(2) contacting the tea extract mixture with a synthetic adsorbent;
(3) a step of eluting ethylenediaminetetraacetic acid or a salt thereof with water or an organic solvent aqueous solution having an organic solvent concentration of less than 5% by mass;
(4) a step of eluting non-polymer catechins with an organic solvent aqueous solution having an organic solvent concentration of 10 to 70% by mass;
The method for removing the taste of tea extract is provided.

  Furthermore, this invention provides the container-packed drink formed by filling the container with the refined tea extract obtained by the said manufacturing method.

  ADVANTAGE OF THE INVENTION According to this invention, the refined tea extract with favorable flavor from which the taste was reduced can be provided.

It is the figure which compared the NMR spectrum of fraction KC33362 (1) and KC3342 (2) with (-)-epicatechin gallate (3).

Step (1) of the present invention is a step of adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract.
Examples of the tea extract used in the present invention include extracts obtained from tea leaves of non-fermented tea, semi-fermented tea, and fermented tea depending on the degree of fermentation. The tea extract is a concept that includes a tea extract and contains at least one non-polymer catechin.

Non-fermented tea includes Camellia, such as C.I. sinensis and C.I. Examples include green teas such as sencha, bancha, gyokuro, tencha, and kettle roasted tea made from tea leaves obtained from assamica, Yabukita seeds or hybrids thereof. Semi-fermented tea or fermented tea includes Camellia genus such as C.I. sinensis and C.I. Examples include black tea, oolong tea, black tea, and the like, which are made from tea obtained from assamica, Yabukita seeds, or hybrids thereof through a semi-fermentation or fermentation process. Moreover, you may use the tea leaf which gave the carbon dioxide contact process of the supercritical state. Among them, an extract of non-fermented tea having a high content of non-polymer catechins is preferable, and a green tea extract is particularly preferable. The content of non-polymerized catechins in the solid content of the tea extract is preferably 10% by mass (hereinafter simply referred to as “%”) or more in order to easily consume a large amount of non-polymer catechins, and in particular, 20 % Or more is preferable.
In the present invention, non-polymer catechins are non-epimeric catechins such as catechin, gallocatechin, catechin gallate and gallocatechin gallate, and epicatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate and the like. It is a collective term for all body catechins. The concentration of non-polymer catechins is defined based on these total amounts.

  As a method for extracting tea, conventional methods such as stirring extraction and drip extraction can be employed. Moreover, you may add organic acids or its salts, such as ascorbic acid or its sodium salt, to the water at the time of extraction previously. Furthermore, a method of extracting under a non-oxidative atmosphere while removing dissolved oxygen by bubbling degassing or inert gas such as nitrogen gas may be used in combination. The tea extract obtained in this way can be used in the present invention as it is, even if it is dried and concentrated. Examples of the tea extract include liquid, slurry, semi-solid, and solid.

  Further, instead of using a tea extract extracted from tea leaves as a tea extract, the concentration of the tea extract and the tea extract can be obtained by dissolving or diluting the tea extract concentrate in water or an organic solvent. You may use together. Here, the concentrate of tea extract refers to a concentrate obtained by concentrating an extract extracted from tea leaves with hot water or an organic solvent aqueous solution. For example, JP-A-59-219384 and JP-A-4-20589. It can be prepared by the methods described in JP-A-5-260907, JP-A-5-306279, and the like. Moreover, you may use a commercial item as a concentrate of a tea extract, for example, Mitsui Norin Co., Ltd. "Polyphenon", ITO EN Co., Ltd. "Theafranc", Taiyo Kagaku Co., Ltd. "Sunphenon" etc. are illustrated. .

  Examples of the salt of ethylenediaminetetraacetic acid used in the present invention include alkali metal salts such as sodium salt and potassium salt; alkaline earth metal salts such as magnesium and calcium; aluminum salts or alloys thereof. Of these, disodium salt, sodium calcium salt, and calcium disodium salt are preferably used. Further, ethylenediaminetetraacetic acid or a salt thereof includes these hydrates and solvates with solvents.

  As the usage-amount of ethylenediaminetetraacetic acid or its salt, it is preferable to add so that it may become 0.1 to 200% of range with respect to solid content of a tea extract from a viewpoint of reducing a taste. More preferably, it is 0.5 to 150%, and particularly preferably 1.0 to 100%.

  Step (2) is a step of bringing the tea extract mixture after addition of ethylenediaminetetraacetic acid or a salt thereof in step (1) into contact with the synthetic adsorbent.

The synthetic adsorbent used in the present invention is generally a polymer having an insoluble three-dimensional crosslinked structure and substantially free of functional groups such as ion exchange groups. Preferably, those having an ion exchange capacity of less than 1 meq / g can be used. The particle shape of the synthetic adsorbent used in the present invention may be any shape such as a spherical shape or a non-uniform shape, but is preferably a spherical shape in order to satisfy a good separation condition. Examples of commercially available synthetic adsorbents include Amberlite XAD4, FPX66, XAD1180N, XAD2000 (manufactured by Rohm and Haas, USA), Diaion HP20, HP21, Sepabeads SP-850, SP-825, SP-700, SP -70 (Mitsubishi Chemical Co., Ltd.), VPOC1062 (Bayer Co., Ltd.) and other styrenes; Sepabeads SP205, SP206, SP207 (Mitsubishi Chemical Co., Ltd.) etc. Methacrylic such as Diaion HP1MG and HP2MG (Mitsubishi Chemical); phenolic such as Amberlite XAD761 (Rohm and Haas, USA); Amberlite XAD7HP (Rohm and Haas, USA), etc. Acrylic type; TOYOPEARL, HW 40C polyvinyl such as (manufactured by Tosoh Corporation); SEPHADEX, dextran-based, such as LH-20 (Pharmacia) and the like.
Among them, as the synthetic adsorbent, those whose matrix is styrene, methacrylic, acrylic or polyvinyl are preferred, and those which are especially styrene are non-polymer catechins and ethylenediaminetetraacetic acid or a salt thereof. It is preferable from the viewpoint of separability and removal of impurities.

  The amount of the synthetic adsorbent used is such that the ratio of the total mass of non-polymer catechins in the tea extract mixture to the total capacity of the synthetic adsorbent is 20 to 60 g / L, more preferably 25 to 55 g / L, especially 30. It is preferable to select an amount of ˜50 g / L from the viewpoint of the removal efficiency of impurities and the recovery rate of non-polymer catechins.

  The method of bringing the tea extract mixture into contact with the synthetic adsorbent is to add the synthetic adsorbent to the tea extract mixture and stir to adsorb non-polymer catechins, and then collect the synthetic adsorbent by filtration. Method; Alternatively, a column method in which the tea extract mixture is passed through a column packed with a synthetic adsorbent and subjected to continuous adsorption treatment can be employed, but a continuous treatment method using a column is preferred from the viewpoint of productivity.

In addition, before a process, it is preferable to wash | clean a synthetic adsorbent from a viewpoint of the removal of the impurity in a synthetic adsorbent, and the improvement of adsorption ability. As a washing method, for example, water having a flow rate of SV = 0.5 to 10 [h ⁻¹ ] and a flow rate of 2 to 10 [L / L] with respect to the total capacity of the synthetic adsorbent is columnized The method of letting liquid pass through is mentioned. Examples of water include tap water, purified water, distilled water, and ion exchange water. In addition, before passing water, the flow rate is SV (space velocity) = 0.5 to 10 [h ⁻¹ ], and the flow rate is 2 to 10 [L / to the total capacity of the synthetic adsorbent. L] may be passed through a column packed with a synthetic adsorbent to remove impurities in the synthetic adsorbent. Examples of the organic solvent to be used include ketones such as acetone and alcohols such as methanol and ethanol. Among these, alcohols, particularly ethanol is preferable from the viewpoint of use in foods. The concentration of the organic solvent in the organic solvent aqueous solution is preferably 85% or more, particularly preferably 90% or more. Note that the upper limit of the concentration of the organic solvent is preferably 99%, particularly 98%.

Moreover, as conditions for passing the tea extract mixture through the column filled with the synthetic adsorbent, the liquid passing speed is SV = 0.5 to 10 [h ⁻¹ ] and the liquid passing ratio is the synthetic adsorbent. The total capacity is preferably 0.5 to 20 [L / L]. With such a flow rate and a flow rate, non-polymer catechins in the tea extract can be sufficiently adsorbed on the synthetic adsorbent.

Next, an elution step (3) is performed. Step (3) is a step of eluting ethylenediaminetetraacetic acid or a salt thereof with water or an organic solvent aqueous solution having an organic solvent concentration of less than 5%.
The concentration of the organic solvent in the aqueous organic solvent solution used here is preferably less than 4%, more preferably less than 2%, and particularly preferably less than 1% from the viewpoint of eluting ethylenediaminetetraacetic acid or a salt thereof.
Examples of water include tap water, purified water, distilled water, and ion exchange water. Examples of the organic solvent include ketones and alcohols as described above. Among them, alcohols, particularly ethanol is preferable.

The flow conditions of the water or organic solvent aqueous solution are as follows. The flow rate is SV = 0.5 to 10 [h ⁻¹ ], and the flow rate is 0.7 to 4 [total volume of the synthetic adsorbent]. L / L] is preferable, the flow rate is SV = 1 to 8 [h ⁻¹ ], and the flow rate is preferably 0.8 to 3.5 [L / L]. .

  Moreover, the usage-amount of the water or organic-solvent aqueous solution with respect to the total mass of non-polymer catechins is 0.01-0.30 (L / from the point which elutes ethylenediaminetetraacetic acid or its salt, and the point which improves taste. g) is preferable, and 0.01 to 0.25 (L / g) is more preferable, and 0.03 to 0.20 (L / g) is particularly preferable.

Next, an elution step (4) is performed. Step (4) is a step of eluting non-polymer catechins with an organic solvent aqueous solution having an organic solvent concentration of 10 to 70%.
As the organic solvent aqueous solution used here, a mixed system of a water-soluble organic solvent and water is used. Examples of the water-soluble organic solvent include ketones and alcohols in the same manner as described above. Among these, alcohols, particularly ethanol is preferable from the viewpoint of use in foods and drinks. The concentration of the water-soluble organic solvent in the organic solvent aqueous solution is preferably 10 to 65%, more preferably 15 to 60%, particularly 20 to 60%, and particularly preferably 30 to 60%. Thereby, the recovery rate of non-union catechins can be improved, and the taste can be further improved.

The flow rate of the organic solvent aqueous solution was such that the flow rate was SV = 0.5 to 10 [h ⁻¹ ], and the flow rate was 0.7 to 4 [L / L with respect to the total capacity of the synthetic adsorbent. L] is preferable, the flow rate is SV = 1 to 8 [h ⁻¹ ], and the flow rate is preferably 0.8 to 3.5 [L / L]. Thereby, it is possible to recover the non-polymer catechins in a high yield with a smaller amount of the organic solvent used, and to suppress the composition change of the non-polymer catechins before and after purification.

  The amount of the organic solvent aqueous solution used relative to the total mass of the non-polymer catechins is preferably 0.01 to 0.30 (L / g), more preferably 0.01 to 0.25 (L / g), and particularly 0. 0.03 to 0.20 (L / g) is preferable. As a result, it is possible to obtain a high-quality purified tea extract with reduced production load and good flavor.

It is preferable that the eluate obtained by the elution step has a high concentration such as a concentrate obtained by removing water or a dried solid, powder or granulated product.
Examples of the concentration increasing method by concentration or drying include vacuum concentration, reverse osmosis membrane concentration, spray drying, freeze drying, and the like.

  The purified tea extract of the present invention thus obtained has reduced taste of the tea extract, specifically, unpleasant and unpleasant taste, and pungent pungent taste, and ethylenediaminetetraacetic acid or its The acidity derived from the salt is also improved. The purified tea extract of the present invention contains a high concentration of non-polymer catechins, and can also be used in a wide range of applications because it suppresses bitterness, miscellaneous taste, and the like. For example, the purified tea extract of the present invention The product can be used as it is or after diluting or concentrating as necessary, and blended into various beverages and foods. In particular, it is useful to be used for a packaged beverage. Examples of the packaged beverage include tea-based beverages such as green tea, and non-tea beverages such as sports beverages, isotonic beverages, and near water.

  The packaged beverage of the present invention further includes antioxidants, various esters, organic acids, organic acid salts, inorganic acids, inorganic acids, inorganic acid salts, inorganic salts, pigments, emulsifiers, preservatives, seasonings, sweetness Additives such as additives, acidulants, gums, oils, vitamins, amino acids, fruit juices, vegetable extracts, nectar extracts, bitterness and taste inhibitors, pH adjusters, and quality stabilizers can be used alone or in combination. .

  The packaged beverage of the present invention preferably contains non-polymer catechins in an amount of 0.05 to 0.7%, more preferably 0.09 to 0.4%, and particularly preferably 0.1 to 0.3%. When the content of the non-polymer catechins is within this range, the non-polymer catechins are easily ingested.

  The pH (25 ° C.) of the packaged beverage of the present invention is preferably from 3 to 7, more preferably from 4 to 7, and particularly preferably from 5 to 7 in terms of taste and stability of non-polymer catechins.

  As a container filled with the purified tea extract of the present invention, a molded container mainly composed of polyethylene terephthalate (so-called PET bottle), a metal can, a paper container combined with a metal foil or a plastic film, like a general beverage, A normal packaging container such as a bottle is exemplified.

  In addition, the container-packed beverage of the present invention can be sterilized as stipulated by laws and regulations (Food Sanitation Law in Japan) if it can be heat-sterilized after filling into a container such as a metal can. Can be manufactured under certain conditions. For PET bottles and paper containers that cannot be sterilized by retort, sterilize under the same conditions as above, for example, after sterilizing at high temperature and short time with a plate heat exchanger, etc. The method can be adopted. Moreover, you may mix | blend another component with the filled container under aseptic conditions. Furthermore, after sterilization by heating under acidic conditions, the pH can be returned to neutrality under aseptic conditions, or after sterilization by heating under neutral conditions, the pH can be returned to acidic conditions under aseptic conditions.

[Measurement of non-polymer catechins]
The sample was filtered with a filter (0.45 μm), and a packed column (L-column TM ODS, 4.6 mmφ × 250 mm) for octadecyl group-introduced liquid chromatograph using a high performance liquid chromatograph (model SCL-10AVP, manufactured by Shimadzu Corporation). : Manufactured by the Chemical Substance Evaluation Research Organization) and analyzed by a gradient method at a column temperature of 35 ° C. The mobile phase A solution was a distilled aqueous solution containing 0.1 mol / L acetic acid, the B solution was an acetonitrile solution containing 0.1 mol / L acetic acid, the sample injection amount was 10 μL, and the UV detector wavelength was 280 nm. .

Reference example 1
(1) Crude catechin preparation (manufactured by Taiyo Kagaku Co., Ltd., non-polymer catechin concentration = 32.6 w / w%) was separated and purified by ODS column chromatography and ODS preparative HPLC to obtain fractions KC33362 and KC3342. . The NMR spectra of fractions KC33362 and KC3342 were compared with (−)-epicatechin gallate. As a result, it was confirmed that they almost coincided as shown in FIG.

(2) The taste of the crude catechin preparation, fraction KC33362, fraction KC3342, epicatechin gallate, epicatechin gallate-iron complex and epicatechin gallate-calcium complex was evaluated by the panelists. As a result, it was confirmed that the fraction KC33362 and the epicatechin gallate-iron complex had an unpleasant taste remaining after the same quality, and that the KC3342 had a stimulating taste with a tingling sensation.
From the above, it was speculated that the savory taste remaining after the crude catechin preparation was due to the epicatechin gallate-iron complex contained in the tea extract.

Example 1
2.0 g of crude catechin preparation (manufactured by Taiyo Kagaku Co., Ltd., non-polymer catechin concentration = 32.6 w / w%) was dissolved in 5.0 ml of distilled water to obtain a tea extract solution. To the obtained tea extract solution, 2.0 g of EDTA 2Na · 2H ₂ O (Clewat N: manufactured by Nagase ChemteX Corporation, hereinafter simply referred to as “EDTA”) (100 w / w%) and dissolved. A column (diameter 30 mm × height 200 mm) packed with Diaion HP20 (Mitsubishi Chemical Co., Ltd., 100 ml) was passed through 500 ml of a 95 v / v ethanol aqueous solution at SV = 7.5 [h ⁻¹ ]. Impurities were removed. Subsequently, it was washed with 500 ml of distilled water at SV = 5.0 [h ⁻¹ ]. Next, the tea extract mixture after EDTA dissolution was passed through SV = 5.0 [h ⁻¹ ] and adsorbed. Next, 250 ml of distilled water was passed through at SV = 5.0 [h ⁻¹ ] to elute EDTA. Subsequently, 250 ml of a 50 v / v% aqueous ethanol solution was passed at SV = 5.0 [h ⁻¹ ] to obtain a non-polymerized catechins eluate.
The obtained non-polymerized catechin eluate was concentrated under reduced pressure to obtain 1.01 g of a purified tea extract having a solid content.

Example 2
The same operation was performed except that the EDTA in Example 1 was changed to 1.0 g (50 w / w% with respect to the solid content) and the tea extract was dissolved to obtain 1.02 g of a purified tea extract having a solid content. It was.

Example 3
The same operation was performed except that the EDTA in Example 1 was changed to 0.50 g (25 w / w% based on the solid content) and the tea extract was dissolved to obtain 0.99 g of a purified tea extract as a solid content. It was.

Example 4
The same operation was performed except that the EDTA in Example 1 was changed to 0.20 g (10 w / w% based on the solid content) and the tea extract was dissolved to obtain 1.00 g of a purified tea extract as a solid content. It was.

Comparative Example 1
2.0 g of a crude catechin preparation (Taiyo Kagaku Co., Ltd., non-polymer catechin concentration = 32.6 w / w%) was dissolved in 5.0 ml of distilled water to obtain a tea extract solution. A column (diameter 30 mm × height 200 mm) packed with Diaion HP20 (Mitsubishi Chemical Co., Ltd., 100 ml) was passed through 500 ml of a 95 v / v% aqueous ethanol solution at SV = 7.5 [h ⁻¹ ]. The impurities were removed. Subsequently, it was washed with 500 ml of distilled water at SV = 5.0 [h ⁻¹ ]. Next, the obtained tea extract solution was passed and adsorbed at SV = 5.0 [h ⁻¹ ]. Next, 250 ml of distilled water was passed through at SV = 5.0 [h ⁻¹ ]. Subsequently, 250 ml of a 50 v / v% aqueous ethanol solution was passed at SV = 5.0 [h ⁻¹ ] to obtain a non-polymerized catechins eluate.
The obtained non-polymerized catechin eluate was concentrated under reduced pressure to obtain 0.96 g of a purified tea extract having a solid content.

Comparative Example 2
0.2 g of crude catechin preparation was dissolved in 100 ml of distilled water, and 0.2 g of EDTA (100 w / w% based on solid content) was added to obtain a tea extract solution.

Comparative Example 3
The amount of EDTA added in Comparative Example 2 was changed to 0.1 g (50 w / w% based on solid content) to obtain a tea extract solution.

Comparative Example 4
The amount of EDTA added in Comparative Example 2 was changed to 0.05 g (25 w / w% based on solid content) to obtain a tea extract solution.

Comparative Example 5
The amount of EDTA added in Comparative Example 2 was changed to 0.01 g (10 w / w% based on solid content) to obtain a tea extract solution.

Test Example 1 Evaluation of Flavor Crude catechin preparation (manufactured by Taiyo Kagaku Co., Ltd., non-polymer catechins concentration = 32.6 w / w%) dissolved in distilled water, purification obtained in each Example and Comparative Example 1 Non-polymer catechins for the tea extract solids dissolved in distilled water at a ratio of the recovered amount to the solid content before resin purification, and the tea extract dissolved solutions obtained in Comparative Examples 2 to 5 It adjusted with ion-exchange water so that a kind content rate might be 0.175 mass%, and the flavor (egg taste, acidity) was evaluated by the paneler according to the following evaluation criteria. In addition, an egg taste is the evaluation which integrated the unpleasant taste of the aftertaste and the egg taste made into chilli.
The results are shown in Table 1.

[Evaluation criteria for taste]
Score 5: Don't feel savory 4: Feel weak savory 3: Feel a little bit savory 2: Feel a lot of savory 1: Feel a lot of savory [Evaluation criteria for sourness]
Score 5: Does not feel sour 4: Feels sour slightly 3: Feels a little sour 2: Feels sour a lot 1: Feels so much sour

  In Examples 1 to 4, the savory taste felt in the crude catechin preparation solution disappeared due to the addition of EDTA and the treatment with the synthetic adsorbent after the addition. Moreover, the acidity derived from EDTA was not felt. In Comparative Example 1 where only the synthetic adsorbent treatment was performed, the taste could not be removed, and in Comparative Examples 2 to 5 where only EDTA was added, the taste disappeared but the acidity of EDTA was strongly felt. Neither was suitable for practical use.

Example 5 Containerized beverages Containerized beverages described in Table 2 were prepared using the purified tea extract obtained in Example 1. A sterilization treatment and hot pack filling based on the Food Sanitation Law were performed to obtain a packaged beverage.

Claims (3)

Next steps (1) to (4):
(1) adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract;
(2) contacting the tea extract mixture with a synthetic adsorbent;
(3) a step of eluting ethylenediaminetetraacetic acid or a salt thereof with water or an organic solvent aqueous solution having an organic solvent concentration of less than 5% by mass;
(4) a step of eluting non-polymer catechins with an organic solvent aqueous solution having an organic solvent concentration of 10 to 70% by mass;
A method for producing a purified tea extract, which is sequentially performed. Next steps (1) to (4):
(1) adding ethylenediaminetetraacetic acid or a salt thereof to the tea extract;
(2) contacting the tea extract mixture with a synthetic adsorbent;
(3) a step of eluting ethylenediaminetetraacetic acid or a salt thereof with water or an organic solvent aqueous solution having an organic solvent concentration of less than 5% by mass;
(4) a step of eluting non-polymer catechins with an organic solvent aqueous solution having an organic solvent concentration of 10 to 70% by mass;
A method for removing the taste of tea extract.   A packaged beverage formed by filling a container with the purified tea extract obtained by the production method according to claim 1.

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