JP2005168429A - Method for producing tea extract solution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a tea extract solution having less coarse taste, depth and well-balanced flavor, and to provide packaged tea beverage using the tea extract solution. <P>SOLUTION: This method for producing the tea extract solution comprises mixing a tea extract solution (extract solution A) obtained by putting tea leaves into a column type extractor and discharging the extract solution while continuously supplying cold water or hot water, with a tea extract solution (extract solution B) obtained by soaking, stirring and extracting with a kneader extractor so as to bring the weight ratio of nonpolymer catechins in the (A) solution to nonpolymer catechins in the (B) solution to 0.5-1.0. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a tea extract with little miscellaneous taste, good depth, and good flavor balance, and a container-packed tea beverage using the tea extract.

  Conventionally, as a tea extract used for preparing a packaged tea beverage, a method has been adopted in which tea leaves and heated extracted water are put into an open type extraction tank generally called a kneader, and the extract is taken out after stirring. However, in this method, tea leaves are finely broken by stirring, and high molecular weight miscellaneous components are easily extracted, and the aroma components of tea are greatly dissipated. For this reason, there is a problem that the extract has a deep flavor unique to tea leaves but has a lot of miscellaneous taste.

In addition, as a means for obtaining a tea extract having a good flavor, a method has been reported in which tea leaves are deposited in a column-type extractor and the extraction is performed with reduced shear stress on the tea leaves. For example, tea leaves are deposited in a tea extraction tank with a wire mesh, and the extract is taken out from below the tea leaves while supplying water at 0 to 36 ° C. from which dissolved oxygen has been removed, and cooled to −1 to 6 ° C. And removing the precipitate (Patent Document 1), adding 2-3 times the amount of water to the tea leaves and moistening for several minutes, then pouring 2-5 times the amount of hot water at 80-95 ° C. The method (patent document 2) which makes a drinkable tea liquid the elution liquid of a density | concentration 5-10 Brix% by making a drinkable ingredient elute in is reported. However, in the method of performing extraction using a column-type extractor, the obtained extract has little taste and good fragrance, but it is too clean and lacks the deep flavor unique to tea.
JP 2000-50799 A JP-A-6-178651

  An object of the present invention is to provide a method for producing a tea extract with little miscellaneous taste and a unique depth of tea leaves and a good flavor balance, and a packaged tea beverage using the tea extract.

  The present invention relates to a tea extract having a good flavor balance in which a kneader extraction method and a column-type extraction method are appropriately combined to provide a rich flavor, little miscellaneous taste, and a unique depth of tea.

That is, the present invention includes a step of obtaining a tea extract A (extract A) obtained by putting tea leaves into a column type extractor and discharging the extract while continuously supplying cold water or hot water. A) and tea extract B obtained by soaking and extracting with a kneader extractor (the step of obtaining extract B is referred to as step A), the weight of non-polymer catechins in solution A / The present invention provides a method for producing a tea extract that is mixed so that the weight ratio of polymer catechins is 0.5 to 10.
The present invention also provides a packaged tea beverage obtained by directly or diluting the obtained tea extract.

  ADVANTAGE OF THE INVENTION According to this invention, the tea extract which has few miscellaneous tastes, can feel depth, has favorable flavor balance, and can be utilized for filling of a container-packed tea drink directly can be manufactured.

  Non-polymer catechins in the present invention are non-epimeric catechins such as catechin, gallocatechin, catechin gallate, gallocatechin gallate, and epicatechins such as epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, etc. It is a generic name that includes

  The tea leaves used in the present invention include green teas such as sencha, gyokuro, and tencha that are made from tea leaves obtained from Camellia genus, for example, C. sinensis and C. assaimica, Yabukita species or hybrids thereof; Then, there are iron fermented teas, such as iron kannon called oolong tea, color types, golden katsura, wushuiwa tea, and so on; tea leaves of fermented teas such as darjeeling, assam, and sri lanka. Of these, green tea leaves are particularly preferred.

  In step A of the method of the present invention, a column type extractor, for example, a closed column as shown in FIG. 1 is used. The tea leaves 4 are charged into the extraction column 3. By using a closed column, flavor components can be sufficiently recovered.

  In step A, tea leaves are charged into a column-type extractor, and the extract is extracted from the other column while supplying water or cold water from one column. Although a method of circulating cold water or hot water in a tank may be used, the one-pass method is preferable in that the heat history received by the extract is small and the quality deterioration due to heat is small. The direction of liquid flow may be an upward flow or a downward flow.

The extract is immediately cooled to 25 ° C. or lower and filtered as necessary. The higher the extraction ratio in Step A, that is, the weight ratio of the extracted liquid from the column / the charged tea leaves, the higher the extraction rate of non-polymer catechins from tea leaves, but the non-polymer catechins are sufficient. After extraction, it is preferable to end the process promptly in order to prevent flavor deterioration. The extraction magnification is 10 to 100, preferably 12 to 80, and particularly preferably 15 to 60.
A value obtained by dividing the water supply flow rate by the cross-sectional area of the column, that is, the linear velocity of water in the column is 1.0 to 20.0 cm / min, preferably 2.0 to 15.0 cm / min, particularly 3.0 to 10.0 cm / min is preferable. If the linear velocity is too high, the tea leaves will become compact and block. On the other hand, if the linear velocity is too slow, the time of the extraction process becomes long, and the working efficiency is lowered.
The value obtained by dividing the height of the swollen tea leaf layer during extraction by the above linear velocity, that is, the average residence time of water in the tea leaf layer is 0.5 to 15.0 min, preferably 0.7 to 10 0.0 min, particularly 0.9 to 8.0 min is preferable. If the average residence time is too short, the extraction of the non-polymer catechins is insufficient, and if it is too long, the extraction process takes a long time and the working efficiency decreases.
The preparation height of tea leaves before the start of extraction is 30 to 500 mm, preferably 40 to 300 mm, and particularly preferably 50 to 200 mm. If the preparation height is too high, the pressure loss of the tea leaf layer increases and the flow velocity decreases. On the other hand, if the preparation height is too low, the batch size of one extraction becomes small, and it is necessary to perform many extractions, so that the work efficiency is lowered.

  In step B, cold water or hot water and tea leaves are charged into a kneader extractor, extracted according to a conventional method, and tea leaves are separated from the extract by a tea leaf separator. The ratio of extraction ratio, that is, the ratio of the weight of cold water or hot water / the charged weight of tea leaves is preferably 10 to 80, preferably 15 to 60, particularly 20 to 50 in order to improve the flavor. The stirring speed is 3 to 50 rpm, preferably 4 to 30 rpm, particularly 6 to 15 rpm. If the number of rotations is too high, miscellaneous components are excessively produced and the flavor is lowered. On the other hand, if the rotational speed is too low, the extraction efficiency of non-polymer catechins becomes low. As the tea leaf separation plate, a plurality of metal meshes of 50 to 200 mesh are used. The extract is immediately cooled to 25 ° C. or lower and filtered as necessary.

  The water used for the extraction in the step A and the step B may be cold water or hot water, for example, 0 to 95 ° C., preferably 35 to 95 ° C., particularly 55 to 85 ° C. is preferable.

  In the present invention, the tea extract (extract A) obtained in step A and the tea extract (extract B) obtained in step B are mixed with the weight of non-polymer catechins in solution A / in solution B. Mix so that the weight ratio of non-polymer catechins is 0.5-10. If this ratio is less than 0.5, the flavor of the mixed solution after mixing the extract A and the extract B is not good because of the miscellaneous taste. Moreover, when this ratio exceeds 10, the hydrophilic polymer component related to the deep taste of tea is not sufficiently contained, and the flavor of the mixed solution after mixing the extract A and the extract B is light. There is nothing. By mixing so that the ratio is 0.5 to 10, an extract having a good flavor balance can be obtained.

  Since the tea extract thus obtained has little miscellaneous taste and has a characteristic depth of tea and a good flavor balance, it can be made into a packaged tea beverage as it is or by dilution. At this time, the concentration of non-polymer catechins is 0.05 to 0.5% by weight, preferably 0.06 to 0.5% by weight, more preferably 0.07 to 0.5% by weight, and still more preferably 0. 0.08 to 0.4 wt%, particularly preferably 0.09 to 0.4 wt%, most preferably 0.10 to 0.3 wt%, most preferably 0.12 to 0.3 wt% It is preferable to obtain the effect of promoting the accumulation of fat burning of non-polymer catechins, the effect of promoting the burning of dietary fat, the effect of promoting the expression of liver β-oxidized gene (Japanese Patent Laid-Open No. 2002-326932), and the like.

  Further, the ratio of the generic gallate body consisting of catechin gallate, epicatechin gallate, gallocatechin gallate and epigallocatechin gallate in the non-packed tea beverage of the present invention in the total non-polymer catechins is 35 to 100% by weight, The amount of 35 to 98% by weight, particularly 35 to 95% by weight, is preferable in view of the effectiveness of physiological effects of non-polymer catechins.

  The packaged tea beverage of the present invention is preferably mixed with a bitter and astringent taste suppressant because it is easy to drink. As the bitter and astringent taste inhibitor to be used, cyclodextrin is preferable. As the cyclodextrin, α-, β-, γ-cyclodextrin and branched α-, β-, γ-cyclodextrin can be used. The cyclodextrin is contained in the beverage in an amount of 0.005 to 0.5% by weight, preferably 0.01 to 0.3% by weight. The packaged tea beverage of the present invention includes an antioxidant, a fragrance, various esters, an organic acid, an organic acid salt, an inorganic acid, an inorganic acid salt, an inorganic salt, a pigment, an emulsifier, a preservative, a seasoning, and a sweetener. Additives such as acidulants, gums, oils, vitamins, amino acids, fruit juice extracts, vegetable extracts, nectar extracts, pH adjusters and quality stabilizers can be used alone or in combination.

  The pH of the packaged tea beverage of the present invention is preferably 3 to 7, preferably 4 to 7, particularly 5 to 7 at 25 ° C. from the viewpoint of flavor and catechin stability.

The ingested tea beverage of the present invention has a daily intake of adults for producing effects of accumulation fat burning promotion, dietary fat burning promotion and liver β-oxidation gene expression promotion, as non-polymer catechins, 300 mg or more, Preferably it is 450 mg or more, more preferably 500 mg or more. Specifically, anti-obesity effects and visceral fat reduction effects have been confirmed by ingesting 483 mg, 555 mg, 900 mg and the like per beverage (Japanese Patent Laid-Open No. 2002-326932).
Accordingly, in the packaged tea beverage of the present invention, the daily intake for adults is 300 mg or more, preferably 450 mg or more, more preferably 500 mg or more as non-polymer catechins, and the necessary intake per day is ensured. Is preferred.

  The container used for the container-packed tea beverage of the present invention is 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, It can be provided in a conventional form such as a bottle. The term “packaged beverage” as used herein means a beverage that can be drunk without dilution.

  The container-packed tea beverage of the present invention is manufactured under the sterilization conditions stipulated in the Food Sanitation Law if it can be sterilized by heating after filling the container like a metal can. For those that cannot be sterilized by retort, the same sterilization conditions as described above, for example, a high-temperature and short-time sterilization using a plate heat exchanger or the like, followed by cooling to a certain temperature and filling into a container are 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 may be returned to neutrality under aseptic conditions, or after sterilization by heating under neutral conditions, the pH may be returned to acidic conditions under aseptic conditions.

Octadecyl group-introduced liquid chromatograph using a high-performance liquid chromatograph (model SCL-10Avp) manufactured by Shimadzu Corporation, which was filtered with a catechin measurement filter (0.8 μm) and then diluted with distilled water. Packed column L-column TM ODS (4.6 mmφ × 250 mm: manufactured by Chemical Substances Evaluation and Research Institute) was attached, and the gradient method was performed at a column temperature of 35 ° C. The mobile phase A solution was a distilled aqueous solution containing 0.1 mol / L of acetic acid, and the B solution was an acetonitrile solution containing 0.1 mol / L of acetic acid, and the solution was sent at a flow rate of 1.0 mL / min. The gradient conditions are as follows.
Time A liquid B liquid
0 minutes 97% 3%
5 minutes 97% 3%
37 minutes 80% 20%
43 minutes 80% 20%
43.5 minutes 0% 100%
48.5 minutes 0% 100%
The sample injection volume was 10 μL, and the UV detector wavelength was 280 nm.

Extraction apparatus The tea extract of the process A was manufactured using the extraction apparatus shown in FIG. Extraction water was heated by a pump 1 through a heat exchanger for heating ion exchange water, and passed from below to above the extraction column 3. The tea leaves 4 were charged on the tea leaf holding plate 6 in the extraction column. The extract was recovered in the extract recovery tank 8 via the heat exchanger 7 for cooling the extract. The extraction apparatus is not limited to the apparatus shown in FIG. 1 as long as it has a mechanism and a stirrer that can hold tea leaves in a columnar tea leaf filling chamber.

Example 1
100 g of green tea leaves from Miyazaki were packed into a closed extraction column (inner diameter 70 mm, height 137 mm), and ion-exchanged water heated to 65 ° C. was passed from the bottom to the top at a rate of 0.25 L / min. At this time, the initial tea leaf preparation height was 75 mm, the linear velocity was 6.5 cm / min, and the average residence time was 2.2 min. The extract was immediately cooled to 25 ° C. or lower with a heat exchanger. When the weight of the extracted liquid became 60 times the weight of the charged tea leaves, the liquid passing was terminated, and the liquid in the tank was mixed uniformly (liquid A). The concentration of non-polymer catechins in Liquid A was 0.189% by weight. In addition, 4320 g of ion-exchanged water heated to 65 ° C. and 144 g of green tea leaves from Miyazaki were placed in a kneader, and extracted with stirring for 5 minutes while stirring at 12 rpm. Thereafter, the tea leaves were removed from the extract with 80-mesh and 150-mesh tea leaf separators, cooled to 25 ° C. or lower with a heat exchanger, and mixed uniformly (liquid B). The concentration of non-polymer catechins in Liquid B was 0.242% by weight.
Liquid A and liquid B were mixed at a volume ratio of 56:44.

Example 2
Liquid A and liquid B obtained in Example 1 were mixed at a volume ratio of 88:12.

Comparative Example 1
Liquid A and liquid B obtained in Example 1 were mixed at a volume ratio of 15:85.

Comparative Example 2
The liquid A and liquid B obtained in Example 1 were mixed at a volume ratio of 94: 6.

  The mixture of tea extracts obtained in Examples and Comparative Examples was diluted with ion-exchanged water so that the concentration of non-polymer catechins was 0.05% by weight, and the flavor was evaluated by four specialized panelists. did.

(Evaluation criteria)
A: There is no miscellaneous taste, it is deep, and the flavor balance is very good.
◯: A slight taste is felt, but the depth is deep and the flavor is relatively good.
Δ: There is no miscellaneous taste, but the depth is poor and the flavor is slightly poor.
X: Strong taste and poor flavor.

  Table 1 shows the weight ratio of the non-polymer catechins in the mixed solution and the evaluation results of the flavor calculated from the concentrations of the non-polymer catechins in the liquids A and B obtained in Examples and Comparative Examples.

  All of the tea extracts obtained in Examples 1 and 2 had no miscellaneous taste, even if there was little, and the depth unique to tea was sufficiently felt, and the flavor balance was good. On the other hand, the tea extract obtained in Comparative Example 1 had a strong taste and poor flavor. Further, the tea extract obtained in Comparative Example 2 was clean and clear, but the depth was poor and the flavor balance was slightly poor.

It is a figure which shows the outline of the extraction method using the column type extractor at the process A of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pump 2 Ion-exchange water heating exchanger 3 Column type extractor 4 Tea leaf 5 Tea leaf holding plate (top)
6 Tea leaf holding plate (bottom)
7 Heat exchanger for cooling the extract 8 Extract recovery tank

Claims (4)

  Tea extract A obtained by putting tea leaves into a column type extractor and discharging the extract while continuously supplying cold water or hot water and an extract obtained by immersion stirring extraction with a kneader extractor A method for producing a tea extract in which B is mixed so that the weight ratio of non-polymer catechins in liquid A / non-polymer catechins in liquid B is 0.5 to 10.   The method for producing a tea extract according to claim 1, wherein the tea leaves are green tea leaves.   A packaged tea beverage obtained by directly or diluting the tea extract obtained by the method according to claim 1 or 2.   The packaged tea beverage according to claim 3, wherein the concentration of the non-polymer catechins is 0.05 to 0.5% by weight.

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