JP2010110291A - Purified tea extract - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a purified tea extract having a reduced content of caffeine, and having sharp aftertaste. <P>SOLUTION: The purified tea extract includes (A) non-polymerized catechins, (B) the caffeine and (C) a fatty acid ester of glycerol, regulated so that the ratio [(B)/(A)] of the contained masses of the caffeine (B) to the non-polymerized catechins (A) may be ≤0.01. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a purified tea extract with a reduced amount of caffeine.

  As a technique for blending catechins in a beverage at a high concentration, a method of adding a catechin to a beverage in a dissolved state using a tea extract (Patent Documents 1 to 3) such as a concentrate of a green tea extract is known. Yes. However, in the case of adding catechins to the type of beverage for which catechins are blended at a high concentration, for example, tea-based beverages, non-tea-based beverages such as carbonated beverages, etc., bitterness derived from caffeine and green tea The taste remains, and the commercial value of the beverage may be greatly impaired.

JP 2002-142777 A JP-A-8-298930 JP-A-8-109178

  Therefore, the present inventor intended to develop a purified tea extract with a reduced caffeine content, and prepared a non-tea beverage such as a sports beverage using a purified green tea extract with a reduced caffeine content. There was a completely unexpected problem that the refreshing throat required for tea-based beverages was not felt.

  The present inventor studied to find out the cause of the lack of aftertaste in non-tea beverages containing a purified green tea extract with a reduced caffeine content, and when the mellowness unique to green tea is enhanced, the aftertaste is enhanced. It was found that the sharpness of the was weakened. Further, when a non-tea beverage was prepared by blending a purified green tea extract with a reduced caffeine content together with a certain amount of caffeine, the aftertaste was improved. From this result, it was confirmed that the reduction of the amount of caffeine in the purified tea extract has an effect on the sharpness of the aftertaste. And this inventor discovered that the refined tea extract with favorable aftertaste and favorable flavor is obtained by mix | blending glycerol fatty acid ester with the refined tea extract which reduced the caffeine content. In the present invention, “aftertaste” refers to “feeling left in the mouth” described in JIS Z 8144: 2004.

That is, the present invention contains (A) non-polymer catechins, (B) caffeine and (C) glycerin fatty acid ester,
(A) It is in providing the refined tea extract whose content mass ratio [(B) / (A)] of non-polymer catechins and (B) caffeine is 0.01 or less.
Another object of the present invention is to provide a food or drink comprising the purified tea extract.

  According to the present invention, it is possible to provide a high-concentration non-polymer catechin-containing purified tea extract having a good aftertaste and a good flavor despite the reduced caffeine content. In addition, by using the purified tea extract of the present invention, it is possible to provide a refreshing food and drink that has a good flavor when it is contained in the mouth and is clean.

(Purified tea extract)
In the present invention, “(A) non-polymer catechins” refers to non-epimeric catechins such as catechin, gallocatechin, catechin gallate and gallocatechin gallate, epicatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate. In other words, the concentration of non-polymer catechins is defined based on the total amount of the above eight types.

  In the present invention, the “gallate form of non-polymer catechins” is a general term for catechin gallate, gallocatechin gallate, epicatechin gallate and epigallocatechin gallate. The “gallate body ratio in the non-polymer catechins” is a numerical value representing the total mass of these four types of non-polymer catechins as a percentage of the total mass of the eight non-polymer catechins. It is.

  The purified tea extract of the present invention is characterized in that the amount of caffeine is significantly reduced. Specifically, the content of (B) caffeine is 0.01 or less in mass ratio [(B) / (A)] to (A) non-polymer catechins, but 0.008 or less, and It is preferably 0.005 or less, particularly preferably 0.003 or less. In addition, the refined green tea extract of the present invention may not substantially contain caffeine, and the mass ratio [(B) / (A)] may be 0. Here, in the present invention, “substantially does not contain” means that the amount of caffeine is below the detection limit in “Measurement of caffeine” in the examples described later.

The purified tea extract of the present invention has a concentration of (A) non-polymer catechins in the solid content of 60 to 90% by mass, more preferably 70 to 85% by mass, from the viewpoint of expression of physiological effects by non-polymer catechins. It is especially preferable that it is 75-80 mass%.
The purified tea extract of the present invention preferably has a gallate content in the non-polymer catechins of 0.001 to 70% by mass. From the viewpoint of expression of physiological effects and bitterness reduction by the non-polymer catechins, 10 -60 mass%, more preferably 10-40 mass%, particularly preferably 20-30 mass%.

In addition, the purified tea extract of the present invention contains (C) a glycerin fatty acid ester in order to enhance the aftertaste sharpness.
The content of (C) glycerin fatty acid ester in the purified tea extract of the present invention is 0.01 to 0.8 in terms of mass ratio [(C) / (A)] to (A) non-polymer catechins. It is preferably 0.02 to 0.5, more preferably 0.03 to 0.2, and particularly preferably 0.04 to 0.1. Thereby, it can be set as the refined tea extract with much more sharpness.

(C) The glycerin fatty acid ester includes monoacylglycerol, diacylglycerol, and triacylglycerol, but from the viewpoint of providing a sharp aftertaste, it is preferable to contain monoacylglycerol and triacylglycerol. The constituent fatty acid of the glycerin fatty acid ester may be linear or branched, saturated or unsaturated, but is preferably a linear or branched saturated aliphatic carboxylic acid.
Moreover, 2-18 are preferable and, as for carbon number of the constituent fatty acid of (C) glycerin fatty acid ester, it is preferable that it is 2-10, especially 2-4 from a viewpoint made into a still more crisp aftertaste. (C) When the glycerin fatty acid ester is triacylglycerol, a glycerin triacetic acid ester having 2 carbon atoms in the constituent fatty acid is particularly preferable. When the glycerin fatty acid ester is monoacylglycerol, glyceryl monocaprate is preferred.

In order to obtain a purified tea extract having a mass ratio (B) / (A) within the above range, it is necessary to reduce the absolute amount of caffeine. Examples of the method include the following purification methods (i) to (iii).
(I) A method in which a tea extract is treated with tannase and further treated with activated carbon and / or acid clay or activated clay (for example, JP 2007-282568 A).
(Ii) A method in which a tea extract is adsorbed on a synthetic adsorbent and then eluted with an aqueous ethanol solution (for example, JP 2006-160656 A).
(Iii) A method in which a tea extract is adsorbed on a synthetic adsorbent and an eluate obtained by elution with an organic solvent aqueous solution or a basic aqueous solution is treated with activated carbon (for example, JP 2008-079609)

Examples of the tea extract used for purification include an extract obtained from tea leaves. Other caffeine-containing plant extracts, for example, caffeine-containing extracts such as coffee, mixtures thereof with tea extracts, and the like can also be used. Examples of the tea leaves used include tea leaves made from tea leaves obtained from the genus Camellia, for example, C. sinensis and 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.
The tea extract used in the present invention is preferably a green tea extract from the viewpoint of the content of non-polymer catechins.

  As the extraction method, conventional methods such as stirring extraction and drip extraction can be employed. The tea extract thus obtained can be directly used for the purification of (i) to (iii) after being dried or concentrated. Examples of the tea extract include liquid, slurry, semi-solid, and solid.

  Moreover, you may use what melt | dissolved or diluted the concentrate of the tea extract in water or the organic solvent instead of the extract extracted from the tea leaf as a tea extract. Here, the concentrate of tea extract is obtained by concentrating an extract extracted from tea leaves with water and / or a water-soluble organic solvent. For example, JP-A-59-219384 and JP-A-4- It can be prepared by the methods described in JP-A-20589, JP-A-5-260907, JP-A-5-306279, and the like. Commercially available products may be used as the concentrate of the tea extract, such as “Polyphenone” manufactured by Tokyo Food Techno Co., “Theafuran” manufactured by ITO EN, and “Sunphenon” manufactured by Taiyo Kagaku Co., Ltd. Concentrates.

  In order to obtain a purified tea extract having mass ratios (B) / (A) and (C) / (A) within the above range, tea extraction obtained by the methods (i) to (iii) above. (C) Glycerol fatty acid ester is added to the product so that the mass ratio (C) / (A) is within the above range, or the mass ratio (C) / (A) is within the above range ( C) The method of refine | purifying the tea extract which mix | blended glycerol fatty acid ester with the method of said (i)-(iv) is mentioned.

(Food)
The purified tea extract of the present invention is refreshing over the throat, has a good aftertaste, and has a good flavor, so it can be used as it is in food and drink. In that case, the solvent may be removed by a method such as vacuum concentration or thin film concentration. Moreover, when powder is desirable as a product form of the purified green tea extract, it can be pulverized by a method such as spray drying or freeze drying.

  The content of the purified tea extract of the present invention in foods and drinks can be appropriately selected depending on the type, but is generally 0.1 to 20% by mass, particularly 0.1 to 10% by mass. It is preferable.

Examples of the beverage of the present invention include tea beverages and non-tea beverages. Examples of tea beverages include green tea beverages, oolong tea beverages, and black tea beverages. Non-tea beverages include soft drinks (eg fruit juice, vegetable juice, sports drinks, isotonic drinks), non-alcoholic drinks such as coffee drinks, nutrition drinks, beauty drinks, beer, wine, sake, plum wine. , Alcoholic beverages such as sparkling liquor, whiskey, brandy, shochu, rum, gin, liqueur and the like.
Examples of food include confectionery (eg, baked confectionery such as bread, cake, cookies, biscuits, chewing gum, chocolate, candy), dessert (eg, jelly, yogurt, ice cream), retort food, seasoning (For example, sauce, soup, dressing, mayonnaise, cream). In addition, the form of food / beverage products is not specifically limited, As long as it is a form which is easy to ingest, any of solid, powder, liquid, gel form, slurry form, etc. may be sufficient. Especially, as a food-drinks of this invention, a drink is especially preferable.

  The beverages of the present invention include antioxidants, fragrances, organic acids, organic acid salts, inorganic acids, inorganic acid salts, inorganic salts, pigments, emulsifiers, preservatives, seasonings, sweeteners, acidulants, gums, oils. Additives such as vitamins, amino acids, fruit juice extracts, vegetable extracts, nectar extracts, pH adjusters, and quality stabilizers may be used alone or in combination.

  The pH (25 ° C.) of the beverage of the present invention is preferably 2 to 7, and particularly preferably 2 to 6.5 from the viewpoint of taste and stability of non-polymer catechins.

In addition, the beverage of the present invention is a container packed in a normal packaging container such as 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, or a bottle. Offered as a beverage.
In addition, for example, in the case where the container-packed beverage can be sterilized by heating after filling the container like a metal can, it can be manufactured under the sterilization conditions defined in the Food Sanitation Law. 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 sample solution was filtered with a filter (0.45 μm) and used for high performance liquid chromatograph (model SCL-10AVP) manufactured by Shimadzu Corporation for octadecyl group-introduced liquid chromatograph. A packed column L-column TM ODS (4.6 mmφ × 250 mm: manufactured by Chemical Substance Evaluation Research Organization) was attached, and analysis was performed at a column temperature of 35 ° C. by a gradient method. The mobile phase A solution was a distilled aqueous solution containing 0.1 mol / L of acetic acid, the B solution was an acetonitrile solution containing 0.1 mol / L of acetic acid, the sample injection amount was 20 μL, and the UV detector wavelength was 280 nm. .

(2) Measurement of glycerin fatty acid ester Measurement was performed by gas chromatography using a gas chromatograph (Agilent Technologies, 6890N).

(3) Evaluation of aftertaste of purified tea extract 40 mL of the purified tea extract obtained in each Example and Comparative Example was placed in a 50 mL pressure-resistant glass container. Thereto was added 0.1% by mass of sodium ascorbate, the pH was adjusted to 6.4 with a 5% by mass aqueous sodium hydrogen carbonate solution, nitrogen substitution was performed, and the mixture was sterilized by heating in an autoclave at 121 ° C. for 10 minutes. Thereafter, a sensory test was conducted by four specialized panelists. The sensory test evaluated the aftertaste sharpness immediately after drinking according to the following criteria, and used the averaged result.

Score 5: Sharply felt aftertaste.
4: Feels sharp aftertaste.
3: Feels slightly weak aftertaste.
2: Feels weak in aftertaste.
1: There is no sharpness in the aftertaste.

Example 1
Add 45 kg of hot water at 88 ° C to 3 kg of green tea leaves (Kenya, large leaf seed), extract with stirring for 60 minutes, perform coarse filtration with a 100 mesh wire net, then centrifuge to remove fines in the extract To obtain 37.2 kg (pH 5.4) of “green tea extract”. The obtained green tea extract had a non-polymer catechin concentration of 0.89% by mass, a gallate content in the non-polymer catechins of 52.3% by mass, and a caffeine concentration of 0.17% by mass. .
This green tea extract was maintained at a temperature of 15 ° C., tannase (Kikkoman, Tannase KTFH, 500 U / g) was added at a concentration of 430 ppm with respect to the green tea extract, maintained for 55 minutes, and a gallate body fraction of 30 When it reached 0.5 mass%, the solution was heated to 90 ° C. and held for 2 minutes to deactivate the enzyme, and the reaction was stopped (pH 5.1). Subsequently, concentration treatment was performed under reduced pressure concentration to a Brix concentration of 20% under conditions of 70 ° C. and 6.7 kpa, and further spray-dried to obtain 0.9 kg of powdered “tannase-treated green tea extract”. The obtained green tea extract had a non-polymer catechin concentration of 27.8% by mass, a gallate content in the non-polymer catechins of 30.3% by mass, and a caffeine concentration of 6.74% by mass. . 285 g of “tannase-treated green tea extract” was dissolved in 8550 g of ion-exchanged water with stirring at 25 ° C. for 30 minutes (tannase-treated solution).

Next, a stainless steel column 1 (inner diameter 110 mm × height 230 mm, volume 2185 mL) was filled with 2209 mL of a synthetic adsorbent (Separbeads SP-70, manufactured by Mitsubishi Chemical Corporation). Stainless steel column 2 (inner diameter 38 mm × height 770 mm, volume 877.4 mL) was charged with 852 mL of ion exchange resin (Diaion SK1BH, manufactured by Mitsubishi Chemical Corporation). In both columns, SV = 5 (h ⁻¹ ) and 95% (v / v) ethanol through 4 times volume (vs. packed resin), and then 10 times volume (vs. filled resin) of water. Washed. Thereafter, 8835 g of the tannase treatment solution (4 volumes vs. synthetic adsorbent) was passed through the column 1 at SV = 1 (h ⁻¹ ), and the permeate was discarded. It was then washed with 2209 mL (1 volume vs. synthetic adsorbent) of water at SV = 2 (h ⁻¹ ). After washing with water, 0.1 wt% sodium hydroxide aqueous solution (pH 12.4) was 13256mL passed through at ^{SV = 5 (h -1) (} 6 times volume of the synthesized adsorbent). The eluate was continuously passed through column 2 for deionization to obtain 13080 g (pH 3.3) of green tea extract. This green tea extract had a non-polymer catechin concentration of 0.38% by mass, a gallate content in the non-polymer catechins of 28.6% by mass, and a caffeine concentration of 0% by mass. The concentration of non-polymer catechins in the solid content of the tea extract was 69.0% by mass. Furthermore, it concentrated under reduced pressure on 40 degreeC and 2.6 kPa conditions, and concentrated to the non-polymer catechin density | concentration of 6 mass% (turbidity 208NTU). Subsequently, it passed through a 0.8 μm cellulose acetate membrane (ADVANTEC: C080A090C), and was subjected to solid-liquid separation from the suspension to obtain “resin-treated product 1” (turbidity 1.5 NTU).

Next, 6.5 g of granular activated carbon (Taiko SGP, manufactured by Futamura Chemical Co., Ltd.) was packed in the stainless steel column 3 (inner diameter 22 mm × height 145 mm, volume 55.1 mL). The "resin-treated product 1" non-polymer catechins and prepared such that the ethanol concentration of 20% by weight 4 wt%, was passed through the 267g to column 3 at SV = 2 (h ^-1) (activated charcoal Is 0.6) relative to the amount of non-polymer catechins. Subsequently, filtration was performed with a 0.2 μm membrane filter. Finally, 50 g of ion-exchanged water was added, ethanol was distilled off under conditions of 40 ° C. and 2.7 kPa, and then the water content was adjusted to obtain a green tea extract (2.1 NTU). The green tea extract after the purification treatment has a non-polymer catechin concentration of 13.7% by mass, a gallate content in the non-polymer catechins of 23.5% by mass, a caffeine concentration of 0% by mass, and a solid content. The concentration of non-polymer catechins in the mixture was 79.6% by mass. This green tea extract is designated as non-polymer catechins A.

  Subsequently, it diluted with ion-exchange water so that the non-polymer catechin density | concentration of non-polymer catechin A might be set to 0.175 mass%. Next, glycerin triacetate was added to the solution so that the mass ratio (C) / (A) was a ratio shown in Table 1. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Examples 2 and 3
A purified green tea extract was prepared in the same manner as in Example 1 except that the amount of glycerin triacetate added was changed. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Example 4
A purified green tea extract was prepared in the same manner as in Example 1 except that glycerin triacetate was changed to glyceryl monocaprate. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Example 5
100 g of polyphenone HG (manufactured by Mitsui Norin Co., Ltd.) as a concentrate of green tea extract is dispersed in 900 g of 95.0 mass% ethanol, aged for 30 minutes, filtered through No. 2 filter paper and 0.2 μm pore size filter paper, 200 mL of exchange water was added, and the solution was concentrated under reduced pressure. Of these, 75.0 g was put into a stainless steel container, and the total amount was adjusted to 1,000 g with ion-exchanged water, and adjusted to pH 5.5 by adding 3.0 g of a 5 mass% sodium bicarbonate aqueous solution. Subsequently, under stirring conditions of 22 ° C. and 150 r / min, 0.27 g of tannase (tannase KTFH, Industrial Grade, 500 U / g or more, manufactured by Kikkoman) in 1.07 g of ion-exchanged water (based on non-polymer catechins) 2.4%) was added, and the enzyme reaction was terminated when the pH dropped to 4.24 55 minutes later. Next, the stainless steel container was immersed in a warm bath at 95 ° C. and kept at 90 ° C. for 10 minutes to completely deactivate the enzyme activity, and after cooling to 25 ° C., concentration treatment was performed to obtain a green tea extract. The green tea extract after the purification treatment is 15.0% by mass of non-polymer catechins and 0.017 of caffeine / non-polymer catechins. The gallate content was 44%, and the concentration of non-polymer catechins in the solid content was 61.6% by mass. This green tea extract is designated as non-polymer catechins B.

  Subsequently, the non-polymer catechins B and the non-polymer catechins A were mixed so that the concentration of the non-polymer catechins was 0.0875% by mass, respectively, and diluted with ion-exchanged water. Next, glycerin triacetate was added to the solution so that the mass ratio (C) / (A) was a ratio shown in Table 1. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Comparative Example 1
The purified green tea extract A in Example 1 was diluted with ion-exchanged water so that the concentration of non-polymer catechins was 0.175% by mass, and the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Comparative Examples 2 and 3
A purified green tea extract was prepared in the same manner as in Example 1 except that glycerin triacetate was changed to β-cyclodextrin. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

Reference Example A purified green tea extract was prepared in the same manner as in Example 1 except that glycerin triacetate was changed to caffeine. And the aftertaste of the obtained purified green tea extract was evaluated. The results are shown in Table 1.

  From Table 1, it was confirmed that the cause that the aftertaste sharpness of the non-polymer catechins A is not felt is due to the reduction of the caffeine content (Comparative Example 1 and Reference Example). And even if the amount of β-cyclodextrin, which is a bitter taste inhibitor, is added to the purified tea extract with a reduced caffeine content, the aftertaste is not improved at all (Comparative Examples 2 and 3), but glycerin fatty acid ester. In particular, it was found that the sharpness of the aftertaste was remarkably improved by adding triacylglycerol (Examples 1 to 3).

Example 6
Using the purified tea extract of Example 2, a beverage was prepared according to the formulation described in Table 2. This beverage was subjected to sterilization treatment and hot pack filling based on the Food Sanitation Law to obtain a packaged beverage. The aftertaste of the obtained container-packed beverage was evaluated. The results are shown in Table 2.

Comparative Example 4
Instead of the purified tea extract of Example 2, a container-packed beverage was prepared in the same manner as in Example 6 except that non-polymer catechins A were blended, and the aftertaste was evaluated for sharpness. The results are shown in Table 2.

  The container-packed beverage obtained in Example 6 had a good appearance and was easy to drink and had a crisp aftertaste. Also, from Table 2, when non-polymer catechins A with reduced caffeine content are made into acidic beverages, the aftertaste is slightly improved (Comparative Example 5), but when glycerin triacetate is added to this beverage, It was found that the aftertaste sharply improved (Example 6).

Claims (7)

(A) non-polymer catechins, (B) caffeine and (C) glycerin fatty acid ester,
(A) A purified tea extract having a mass ratio [(B) / (A)] of non-polymer catechins and (B) caffeine of 0.01 or less.   The purified tea extract according to claim 1, wherein the mass ratio [(C) / (A)] of (A) non-polymer catechins and (C) glycerin fatty acid ester is 0.01 to 0.8. .   (C) The purified tea extract according to claim 1 or 2, wherein the glycerin fatty acid ester is triacylglycerol.   The purified tea extract according to claim 3, wherein the triacylglycerol is glycerin triacetate.   The purified tea extract according to any one of claims 1 to 4, wherein the concentration of (A) non-polymer catechins in the solid content is 60 to 90% by mass.   The purified tea extract according to any one of claims 1 to 5, which is a purified green tea extract.   Food-drinks which mix | blend the refined tea extract of any one of Claims 1-6.