JP2010268703A - Method for producing purified tea extract - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a purified tea extract, by which non-polymerized catechins can be recovered in a good yield. <P>SOLUTION: This method for producing the purified tea extract comprises the following processes (1) to (4): (1) the process for hydrolyzing a tea extract; (2) the process for bringing the hydrolyzed tea extract into contact with a synthetic adsorbent to adsorb a non-polymerized catechins in the tea extract to the synthetic adsorbent; (3) the process for washing the synthetic adsorbent with ≤20°C water; and (4) the process for bringing the synthetic adsorbent into contact with a ≤20°C aqueous organic solvent solution to elute the non-polymerized catechins. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a purified tea extract.

  A method of adding catechins to a beverage in a dissolved state using a tea extract such as a green tea extract concentrate is known. However, when catechins are blended at a high concentration, the bitterness tends to increase mainly due to the catechin gallate.

  As a means for improving this bitterness, for example, a method has been proposed in which a gallate body of a non-polymer catechin is hydrolyzed by an enzyme having tannase activity to reduce the proportion of the gallate body in the non-polymer catechin. (Patent Documents 1 and 2). Although this method is effective in reducing the gallate form of non-polymer catechins that cause bitterness, the flavor of the resulting purified tea extract is not always sufficient because it exhibits acidity due to by-product gallic acid. .

  Therefore, in order to remove impurities such as gallic acid, there is a method in which a tea extract is passed through a column packed with a synthetic adsorbent, and then non-polymer catechins adsorbed on the synthetic adsorbent are eluted with an aqueous ethanol solution. It has been proposed (Patent Document 3).

JP 2004-321105 A JP 2005-130809 A JP 2006-160656 A

  However, the purification method using a synthetic adsorbent is effective in reducing impurities such as gallic acid, but the recovery rate of non-polymer catechins is not always sufficient, and there is room for improvement.

  Therefore, the present inventors have studied to improve the recovery rate of non-polymer catechins. As a result, after adsorbing the tea extract to the synthetic adsorbent, the step of washing the synthetic adsorbent and the non-polymer catechins It has been found that non-polymer catechins can be recovered in a high yield by controlling the temperature in the elution step to a predetermined temperature or lower. Furthermore, the present inventors have unexpectedly found that rutin and caffeine, which are flavonol glycosides, in a purified tea extract can be reduced.

That is, the present invention includes the following steps (1) to (4):
(1) a step of hydrolyzing the tea extract;
(2) contacting the hydrolyzed tea extract with a synthetic adsorbent, and adsorbing non-polymer catechins in the tea extract onto the synthetic adsorbent;
(3) Purified tea comprising a step of washing the synthetic adsorbent with water at 20 ° C. or lower, and (4) a step of bringing the organic adsorbent aqueous solution at 20 ° C. or lower into contact with the synthetic adsorbent to elute non-polymer catechins. A method for producing an extract is provided.

The present invention also includes the following components (A), (B) and (C):
(A) Non-polymer catechins (B) Galate bodies of non-polymer catechins, and (C) Rutin,
Containing
The content of (A) non-polymer catechins in the solid content is 20 to 90% by mass,
(A) The ratio of the gallate body of (B) non-polymer catechins in non-polymer catechins is 0.01-49 mass%,
The mass ratio of (C) rutin and (A) non-polymer catechins is 0.001 to 0.025.
A purified tea extract is provided.

  According to the production method of the present invention, it is possible to recover non-polymer catechins in a high yield, and purified tea extraction with reduced rutin and caffeine as well as gallate bodies of non-polymer catechins A thing can be manufactured efficiently. Therefore, this purified tea extract is useful as a raw material for foods and drinks containing a high concentration of non-polymer catechins and having reduced bitterness and astringency.

First, terms used in this specification will be described.
“(A) Non-polymer catechins” refers to non-epimeric catechins such as catechin, gallocatechin, catechin gallate, and gallocatechin gallate, and epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate. It is a collective term for body catechins. The concentration of non-polymer catechins is defined based on the total amount of the above eight types.
“(B) Galate form of non-polymer catechins (hereinafter also referred to as (B) gallate form”) is a general term for catechin gallate, gallocatechin gallate, epicatechin gallate, epigallocatechin gallate and the like. "(A) Ratio of (B) gallate body in non-polymer catechins" is a mass ratio of the gallate body to the total amount of non-polymer catechins.
“(C) Rutin” is a kind of flavonol glycoside in which β-lutinose (6-O-α-L-rhamnosyl-D-β-glucose) is bound to the oxygen atom at the 3-position of quercetin. The (C) rutin content can be quantified by HPLC measurement described in the Examples below.

First, the purified tea extract of the present invention will be described.
The purified tea extract of the present invention contains the above components (A) to (C), but contains (A) non-polymer catechins at a high concentration, and (B) gallate and (C) rutin. Is reduced.

Specifically, the content of (A) non-polymer catechins in the solid content is 20 to 90% by mass, but from the viewpoint of flavor and economy, 30 to 80% by mass, and further 40 to 75% by mass. In particular, the content is preferably 50 to 70% by mass.
The proportion of (B) gallate body in (A) non-polymer catechins is 0.01 to 49% by mass, but from the viewpoint of reducing bitterness and astringency, 0.1 to 45% by mass, It is preferable that it is 1-40 mass%, especially 2-35 mass%.
Furthermore, the content mass ratio of (C) rutin and (A) non-polymer catechins is 0.001 to 0.025 mass%, but from the viewpoint of flavor and economy, 0.002 to 0.025 mass. %, More preferably 0.005 to 0.022% by mass, and particularly preferably 0.01 to 0.02% by mass.
In addition, the purified tea extract of the present invention has a significantly reduced (D) caffeine content, and specifically, a content mass ratio of (D) caffeine to (A) non-polymer catechins. Is preferably 0.01 to 0.17, more preferably 0.02 to 0.14, and particularly preferably 0.03 to 0.12.

Such a purified tea extract can be obtained from the tea extract by fractionation. Specifically, it can be produced by the following method.
That is, although the manufacturing method of the refined tea extract of this invention is characterized by including the said process (1)-(4), process (1) hydrolyzes the (B) gallate body in a tea extract. The steps (2) to (4) remove impurities such as gallic acid, (D) caffeine and (C) rutin in the tea extract after hydrolysis. This is a step of selectively obtaining non-polymer catechins. Hereinafter, each step will be described in detail.

[Step (1)]
Step (1) according to the present invention is a step of hydrolyzing the tea extract.
Examples of the tea extract used in this step include a tea extract obtained from tea leaves. A mixture of a caffeine-containing extract such as coffee and a tea extract derived from other caffeine-containing plants can also be used. Specific examples of tea leaves to be used include tea leaves made from tea leaves obtained from the genus Camellia, such as C. sinensis, C. assamica, Yabuki species, or hybrids thereof. The tea leaves produced include green teas such as sencha, bancha, gyokuro, tencha, roasted tea, semi-fermented tea typified by oolong tea, and fermented tea typified by black tea. Moreover, you may use the tea leaf which gave the carbon dioxide contact process of the supercritical state. Among them, as the tea extract, a green tea extract is preferable from the viewpoint of the content of non-polymer catechins.

  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. Further, a method of extracting in a non-oxidative atmosphere while removing dissolved oxygen by bubbling degassing or inert gas such as nitrogen gas may be used in combination.

  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 is 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. . In addition, although a tea extract may be as it is, dried or concentrated, it is adjusted to the state of aqueous solution before using for a process (1).

Enzymatic treatment is preferably used for the hydrolysis in this step. As an enzyme to be used, an enzyme having tannase activity is preferably used from the viewpoint of processing efficiency. Examples of the enzyme having tannase activity include tannase obtained by culturing tannase-producing bacteria belonging to the genus Aspergillus, Penicillium, and Rhizopus. Among these, those derived from Aspergillus oryzae are preferable. In addition, as a concrete hydrolysis method, the method of Unexamined-Japanese-Patent No. 2004-321105 is employable, for example.
In this way, a hydrolyzed tea extract is obtained, but the hydrolyzed tea extract may be used as it is in the next step, or may be filtered, concentrated, etc. if necessary.

[Step (2)]
Step (2) is a step in which the tea extract after hydrolysis is brought into contact with a synthetic adsorbent, and non-polymer catechins in the tea extract are adsorbed onto the synthetic adsorbent.
The synthetic adsorbent used in this step is preferably one having a fine particle diameter from the viewpoint of improving the recovery rate of non-polymer catechins. Specifically, the average particle diameter (d50) of the synthetic adsorbent is preferably 100 to 500 μm, more preferably 150 to 450 μm, and particularly preferably 200 to 400 μm. Here, the “average particle diameter” in the present specification is measured by a laser diffraction / scattering method based on Mie scattering theory, and specifically, by a particle size distribution measuring apparatus using a laser diffraction / scattering method. The median diameter (d50) obtained by creating the particle size distribution of the synthetic adsorbent on the basis of the number is the average particle diameter.

Such a synthetic adsorbent may be produced by a known method. For example, a synthetic adsorbent having a desired average particle diameter may be collected by sieving a commercially available synthetic adsorbent.
Commercially available synthetic adsorbents include, for example, Amberlite XAD4, XAD16HP, XAD1180, XAD2000 (supplier: Rohm & Haas, USA), Diaion HP20, HP21 (Mitsubishi Chemical), Sepabeads SP850, SP825, SP700, Styrenes such as SP70 (Mitsubishi Chemical), VPOC1062 (Bayer), etc .; substituted styrenes with improved adsorption capacity by introducing bromine atoms into aromatic rings such as Sepabeads SP205, SP206, SP207 (Mitsubishi Chemical) Methacrylic such as Diaion HP1MG, HP2MG (Mitsubishi Chemical); phenolic such as Amberlite XAD761 (Rohm and Haas); acrylic such as Amberlite XAD7HP (Rohm and Haas); TOYOPEARL, HW -40C Examples thereof include polyvinyls such as Tosoh Corp .; and dextrans such as SEPHADEX and LH-20 (Pharmacia).
Among them, as the synthetic adsorbent, the matrix is preferably styrene (especially styrene-divinylbenzene copolymer), methacrylic, acrylic, or polyvinyl, and styrene is particularly preferable for non-polymer catechins and impurities. It is preferable from the viewpoint of separability.

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

  As a method of adsorbing non-polymer catechins in the tea extract after hydrolysis, a synthetic adsorbent is added to the tea extract, stirred and adsorbed, and then the synthetic adsorbent is recovered by filtration. Alternatively, a column method in which adsorption treatment is continuously performed using a column filled with a synthetic adsorbent can be employed, but a continuous treatment method using a column is preferable from the viewpoint of productivity.

Before the adsorption treatment, it is preferable to wash the synthetic adsorbent from the viewpoint of removing impurities in the synthetic adsorbent and improving the adsorption ability of non-polymer catechins. Examples of the cleaning method include the following methods. First, the synthetic adsorbent is filled with an ethanol aqueous solution under the conditions of space velocity (SV) = 0.5 to 10 [h ⁻¹ ] and liquid passage ratio to the synthetic adsorbent (BV) = 2 to 10 [v / v]. The impurities in the synthetic adsorbent are removed by passing through a separate column. Next, water is passed through the column under conditions of SV = 0.5 to 10 [h ⁻¹ ] and BV = ^{1 to} 60 [v / v] to replace ethanol in the column with water.

  When the non-polymer catechins are adsorbed on the synthetic adsorbent, the concentration of the non-polymer catechins in the tea extract is 0.1 to 10% by mass, more preferably 0.2 to 5% by mass, particularly 0.5 to 2 mass% is preferable from the viewpoint of the adsorption efficiency to the synthetic adsorbent.

When the tea extract is passed through a column packed with a synthetic adsorbent, SV = 0.3 to 5 [h ⁻¹ ], BV = 0.5 to 10 [v / v], particularly BV = 0. It is preferable to pass the liquid under conditions of 5 to 5 [v / v]. At that time, the tea extract may be cooled to a temperature of 20 ° C. or lower, further 18 ° C. or lower, particularly 15 ° C. or lower. By setting it as such a liquid-flowing condition, the non-polymer catechins in the tea extract can be sufficiently adsorbed on the synthetic adsorbent. The lower limit of the temperature of the tea extract is not particularly limited as long as it is equal to or higher than the freezing point, but is preferably 0 ° C.

[Step (3)]
Step (3) is a step of washing the synthetic adsorbent with water of 20 ° C. or lower.
Examples of water used in this step include tap water, purified water, and ion exchange water.
The temperature of water used in this step is 20 ° C. or lower, but is preferably 18 ° C., particularly preferably 15 ° C. or lower. Thereby, the recovery rate of non-polymer catechins can be improved while efficiently removing impurities adhering to the synthetic adsorbent. The lower limit of the temperature of the tea extract is not particularly limited as long as it is equal to or higher than the freezing point, but is preferably 0 ° C.
Further, as the liquid passing condition of ^{water, SV = 0.3~10 [h -1]} , in particular SV = 0.5~5 [h- ^1], and BV = 0.5~3 [v / v], in particular, BV = 0.5 to 2 [v / v] is preferable from the viewpoint of the removal efficiency of impurities and the recovery rate of non-polymer catechins.

[Step (4)]
Step (4) is a step of eluting non-polymer catechins by bringing an organic solvent aqueous solution at 20 ° C. or lower into contact with the synthetic adsorbent.
As the organic solvent aqueous solution used in this step, a mixed system of a water-soluble organic solvent and water is used. Examples of the water-soluble organic solvent include ketones such as acetone and alcohols such as methanol and ethanol. From the viewpoint of use, alcohol, particularly ethanol is preferred. The concentration of the organic solvent is usually 10 to 70% by mass, but 15 to 50% by mass, further 20 to 40% by mass, and particularly 25 to 35% by mass improves the recovery rate of non-polymer catechins. From the viewpoint of

The conditions for passing the organic solvent aqueous solution are preferably SV = 0.3 to 10 [h ⁻¹ ], particularly SV = 0.5 to 5 [h ⁻¹ ], and BV = 0.3 to 10 [h ⁻¹ ]. v / v], in particular, BV = 0.5 to 5 [v / v] is preferable. Thereby, (A) non-polymer catechins can be recovered in a high yield, and a purified tea extract in which (B) gallate, (C) rutin and (D) caffeine are reduced can be obtained.

The eluate obtained in this step may be subjected to solid-liquid separation after depositing the precipitate by concentrating or adding water, and the precipitate may be removed. Thereby, the taste and stability of the purified tea extract can be further improved.
The aging time for depositing the turbid component is not particularly limited, but is preferably 2 minutes to 50 hours, more preferably 2 minutes to 24 hours, and particularly preferably 5 minutes to 6 hours. Moreover, it is preferable that the precipitation temperature of a turbid component is -5-40 degreeC from the point of the solubility fall of a precipitate, and the separability of the turbid component after turbid component precipitation, and also 5-25 degreeC.
As the operation of solid-liquid separation, a method usually used in the food industry can be adopted. For example, filtration, centrifugation, and the like are exemplified, and these can be performed in combination.

  Thus, the purified tea extract of the present invention can recover (A) non-polymer catechins in a high yield of 90 to 100% by mass, particularly 94 to 99% by mass, Contaminants such as (B) gallate, (C) rutin, and (D) caffeine can be reduced.

  Moreover, the purified tea extract of the present invention is excellent in hue. Specifically, the non-polymer catechin concentration is diluted to 175 mg / 100 mL, and the absorbance at 400 nm when measured with a cell having an optical path length of 10 mm is less than 0.7, particularly less than 0.6. it can. In addition, it is preferable that the minimum of a light absorbency is 0.01. In the case of such absorbance, an appropriate hue can be obtained with an appropriate hue.

The purified green tea extract of the present invention not only improves bitterness and astringency, but also suppresses coloring, so that it can be used in a wide range of applications. For example, the purified green tea extract of the present invention can be used as it is as a raw material for foods and drinks, but it is particularly preferable to use it for packaged beverages such as tea-based beverages or non-tea-based beverages. Moreover, when powder is desirable as a product form of the purified green tea extract, it can be pulverized by a known method such as spray drying or freeze drying.
The packaged beverages of the present invention include antioxidants, various esters, inorganic salts, pigments, emulsifiers, preservatives, seasonings, sweeteners, acidulants, gums, emulsifiers, oils, vitamins, amino acids, vegetables Additives such as extracts, nectar extracts, bitter and astringent taste inhibitors, pH adjusters and quality stabilizers can be used alone or in combination.
The pH (25 ° C.) of the packaged beverage of the present invention is preferably 2 to 7, and preferably 2 to 6.5 from the viewpoints of taste and stability of non-polymer catechins.

  Moreover, the container-packed drink of this invention is manufactured on the sterilization conditions prescribed | regulated to the food hygiene law, for example, when it can heat-sterilize after filling a container like a metal can. 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 is adopted. Moreover, you may mix | blend another component with the filled container under aseptic conditions.

(1) Measurement of non-polymer catechins and caffeine The purified tea extract obtained in each Example and Comparative Example was filtered through a filter (0.45 μm), and a high performance liquid chromatograph (model SCL-10AVP, Shimadzu Corporation) was obtained. And a packed column (L-column TM ODS, 4.6 mmφ × 250 mm: manufactured by Chemical Substances Evaluation and Research Institute) was installed 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. . The gradient conditions are as follows.

Time (minutes) Liquid A concentration (volume%) Liquid B concentration (volume%)
0.0 97 3
5.0 97 3
37.0 80 20
43.0 80 20
43.5 0 100
48.5 0 100
49.0 97 3
60.0 97 3

(2) Measurement of rutin The purified tea extract obtained in each Example and Comparative Example was filtered with a filter (0.45 μm), and a column (Shimpach) was used using a high performance liquid chromatograph (model L-2130, manufactured by HITACHI). (VP ODS, 150 × 4.6 mm ID) was installed, and analysis was performed by a gradient method at a column temperature of 40 ° C. The mobile phase C solution was a distilled aqueous solution containing 0.05% phosphoric acid, the D solution was a methanol solution, the flow rate was 1 mL / L, the sample injection amount was 10 μL, and the UV detector wavelength was 370 nm. The gradient conditions are as follows.

Time (min) Concentration of liquid C (volume%) Concentration of liquid D (volume%)
0.0 95 5
20.0 80 20
40.0 30 70
41.0 0 100
46.0 0 100
47.0 95 5
55.0 95 5

(3) Measurement of particle diameter For the particle diameter measurement of the synthetic adsorbent, a laser diffraction / scattering particle size distribution measuring device (LS 13 320, BECKMAN COULTER) was used. Then, the particle distribution was created on the basis of the number by this apparatus, and the median diameter (d50) was obtained.

(4) Hue Measurement The purified tea extract obtained in each Example and Comparative Example was diluted with ion-exchanged water so that the non-polymer catechin concentration was 175 mg / 100 mL, and the spectrophotometer (UVmini 1240, Shimadzu). (Manufactured by Seisakusho), the sample was placed in a 10 mm square plastic cell, and the absorbance at 400 nm was measured three times to obtain an average value.

(5) Sensory evaluation The purified tea extract obtained in each Example and Comparative Example was diluted with ion-exchanged water so that the non-polymer catechin concentration would be 175 mg / 100 mL, and 40 mL thereof was a 50 mL pressure-resistant glass container. Put in. Thereto was added 0.1% by mass of sodium ascorbate, the pH was adjusted to 6.4 with a 5% by mass aqueous sodium bicarbonate solution, nitrogen substitution was performed, and the mixture was sterilized by heating at 121 ° C. for 10 minutes in an autoclave. Then, 6 panelists evaluated the miscellaneous taste according to the following criteria, and determined the score by consultation.

Evaluation criteria for miscellaneous taste 5: Little miscellaneous taste 4: Slightly miscellaneous taste 3: Slightly miscellaneous taste 2: High miscellaneous taste 1: Pretty miscellaneous taste

The significance of setting the liquid temperature in step (3) to 20 ° C. or less was examined.
Test example 1
Powder obtained by hot water extraction, tannase treatment and spray drying from green tea leaves (from Kenya, large leaf species) [(A) non-polymer catechin concentration is 29.9% by mass, (B) in non-polymer catechins The gallate body ratio is 35.2% by mass, (C) rutin / (A) non-polymer catechins are 0.043, (D) caffeine / (A) non-polymer catechins are 0.179]. The mixture was dissolved in ion-exchanged water with stirring for 30 minutes. The concentration of catechins after dissolution was 0.97% by mass “green tea extract treated with tannase (1)”.
Next, 250 L of a styrene synthetic adsorbent (Mitsubishi Chemical Corporation, average particle size 302 μm) was packed in a stainless steel column (inner diameter 700 mm × 1358 mm). Next, after passing through a 92 mass% aqueous ethanol solution having a liquid flow rate of SV = 1.5 (h ^-1 ) and a liquid flow rate of 10 times the total volume of the synthetic adsorbent, the liquid flow rate was SV. = 1.5 (h ^-1 ), and the washing ratio was 10 times by volume with respect to the total volume of the synthetic adsorbent. Subsequently, tannase-treated green tea extract (1) 1000 kg (4 times volume vs. synthetic adsorbent, liquid temperature 27 ° C.) was passed through the column at a liquid feed rate SV = 1.0 (h ⁻¹ ), and the permeate was discarded. did. Next, a flow rate of SV = 1.0 (h ⁻¹ ) and a flow rate of 1.5 times volume of ion exchange water (25.4 ° C.) with respect to the total capacity of the synthetic adsorbent were passed. Washed.

Test Examples 2-4
The procedure was the same as in Test Example 1 except that the conditions of step (3) were changed to those shown in Table 1.
The ratio of the amount of non-polymer catechins eluted by washing to the amount of non-polymer catechins in the passed green tea extract (1) was defined as the desorption rate of non-polymer catechins.

  From Table 1, it was confirmed that the elimination of non-polymer catechins by washing can be suppressed by setting the liquid temperature in step (3) to 20 ° C. or lower.

Example 1
Using the same column and synthetic adsorbent as in Test Example 1 and changing the conditions of Step (3) to those shown in Table 2, steps (1) to (3) were performed in the same manner as in Test Example 1. went.
Next, an ethanol aqueous solution having an ethanol concentration of 30% by mass was passed through twice the total volume of the synthetic adsorbent (step (4)).
The obtained purified green tea extract has (A) a non-polymer catechin concentration of 1.85% by mass, (A) a non-polymer catechin concentration in the solid content of 68.4% by mass, (B) a non-heavy The proportion of gallate in the combined catechins is 32.6% by mass, (C) rutin / (A) non-polymer catechins are 0.016, (D) caffeine / (A) non-polymer catechins are 0 079. The recovery rate of non-polymer catechins from the tannase-treated green tea extract (1) was 98.1%. Next, the eluate was concentrated under reduced pressure to remove ethanol and subjected to sensory evaluation. As a result, the taste was very small.

Example 2
A stainless steel column (inner diameter 72 mm × 335 mm) was packed with 1070 mL of a styrene-based synthetic adsorbent (manufactured by Mitsubishi Chemical Corporation, average particle size 332.7 μm). Next, the synthetic adsorbent was washed by the same operation as in Test Example 1. Next, 4280 g of tannase-treated green tea extract (1) (4 times volume vs. synthetic adsorbent, liquid temperature 10 ° C.) was passed through the column at a liquid feed rate SV = 1.0 (h ⁻¹ ), and the permeate was discarded. did.
Next, a purified green tea extract was obtained by the same operation as in Example 1 except that the conditions of steps (3) to (4) were changed to those shown in Table 2.
The resulting purified green tea extract has (A) a non-polymer catechin concentration of 1.46% by mass, (A) a non-polymer catechin concentration in the solid content of 68% by mass, and (B) a non-polymer catechin. The ratio of the gallate body in the product is 33.6% by mass, (C) rutin / (A) non-polymer catechins 0.015, (D) caffeine / (A) non-polymer catechins is 0.101. there were. Moreover, the recovery rate of non-polymer catechins from the green tea extract (1) was 94.4%. Next, the eluate was concentrated under reduced pressure to remove ethanol and subjected to sensory evaluation. As a result, the taste was very small.

Comparative Example 1
A column similar to Test Example 1 was packed with 250 L of a styrene-based synthetic adsorbent (manufactured by Mitsubishi Chemical Corporation, average particle size 532.8 μm). Purified green tea extract by the same operation as in Example 1 except that tannase-treated green tea extract (1) was used as a raw material, and the conditions in steps (2) to (4) were changed to those shown in Table 2. Got.
The obtained purified green tea extract has (A) a non-polymer catechin concentration of 2.0% by mass, (A) a non-polymer catechin concentration in the solid content of 60.3% by mass, (B) a non-heavy The proportion of gallate in the combined catechins is 36.3% by mass, (C) rutin / (A) non-polymer catechins are 0.046, (D) caffeine / (A) non-polymer catechins are 0 174. In addition, the recovery rate of non-polymer catechins from the tannase-treated green tea extract (1) was 93.3%. Next, the eluate was concentrated under reduced pressure to remove ethanol and subjected to sensory evaluation.

Comparative Example 2
Using the same column and synthetic adsorbent as in Test Example 1, using tannase-treated green tea extract (1) as a raw material, except that the conditions in steps (2) to (4) were changed to those shown in Table 2 A purified green tea extract was obtained in the same manner as in Example 1.
The obtained purified green tea extract has (A) a non-polymer catechin concentration of 1.79% by mass, (A) a non-polymer catechin concentration in the solid content of 63.7% by mass, (B) a non-heavy The gallate content in the combined catechins is 36% by mass, (C) rutin / (A) non-polymer catechins are 0.029, (D) caffeine / (A) non-polymer catechins are 0.146. there were. The recovery rate of non-polymer catechins from the tannase-treated green tea extract (1) was 93.8%. Subsequently, the eluate was concentrated under reduced pressure to remove ethanol, and sensory evaluation was performed.

  From Table 2, by controlling the temperature in steps (3) and (4) below a predetermined temperature, non-polymer catechins can be recovered in high yield, and not only gallate bodies of non-polymer catechins, It was confirmed that a purified tea extract with reduced flavonol glycoside rutin and caffeine can be efficiently produced. Further, this purified tea extract had a good hue, was free from miscellaneous taste, and was easy to drink.

Claims (6)

Next steps (1) to (4):
(1) a step of hydrolyzing the tea extract;
(2) contacting the hydrolyzed tea extract with a synthetic adsorbent, and adsorbing non-polymer catechins in the tea extract onto the synthetic adsorbent;
(3) Purified tea comprising a step of washing the synthetic adsorbent with water at 20 ° C. or lower, and (4) a step of bringing the organic adsorbent aqueous solution at 20 ° C. or lower into contact with the synthetic adsorbent to elute non-polymer catechins. A method for producing an extract.   The production method according to claim 1, wherein an enzyme having tannase activity is used for hydrolysis.   The manufacturing method of Claim 1 or 2 using what a mean particle diameter (d50) is 100-500 micrometers as a synthetic adsorbent.   The manufacturing method according to any one of claims 1 to 3, wherein a green tea extract is used as the tea extract. The following components (A), (B) and (C):
(A) Non-polymer catechins (B) Galate bodies of non-polymer catechins, and (C) Rutin,
Containing
The content of (A) non-polymer catechins in the solid content is 20 to 90% by mass,
(A) The ratio of the gallate body of (B) non-polymer catechins in non-polymer catechins is 0.01-49 mass%,
The mass ratio of (C) rutin and (A) non-polymer catechins is 0.001 to 0.025.
A refined tea extract.   The purified tea extract according to claim 5, further comprising (D) caffeine, wherein the mass ratio of (D) caffeine to (A) non-polymer catechins is 0.01 to 0.17.