HK1178385B - Process for the production of extract of teas - Google Patents

Description

Preparation method of tea extract

Technical Field

The present invention relates to a method for producing a tea extract having strong sweetness, high-concentrated taste and delicious taste with less astringency from tea leaves at a high yield.

Background

In recent years, commercial products in which tea beverages are filled in cans, PET bottles, or the like have been provided, and consumers have gained high support for their habit of sweetness, and the yield has been increasing. As a recent trend, tea beverages with suppressed astringency, strong taste and strong concentrated flavor are positively preferred.

In the preparation of tea extracts, as a method for treating with an enzyme, for example, the following methods are proposed: a method of extracting tea leaves using protopectinase and cellulase in combination (see patent document 1); a method of treating black tea leaves with tannase (see patent document 2); a method of treating with pectinase, amylase and polyphenol oxidase (see patent document 3); soaking in amylase and proteinA method for producing a cereal tea (hub tea) comprising drying an aqueous solution of an enzyme, a cellulase or a mixture thereof, and then baking the dried product at 100 to 170 ℃ (see patent document 4); a method for producing instant tea by extracting a mixture of a binding starch and at least 1 enzyme selected from the group consisting of α -or β -amylase, cellulase and protease (see patent document 5); a method of moistening the leaves of black tea with tannase and at least one cell wall digesting enzyme (see patent document 6); a method of treating tea leaf extraction residue with cellulase and protease (see patent document 7); a method in which a hot water extract of tea is treated with tannase in advance and then frozen and concentrated (see patent document 8); a method of producing a tea beverage with less turbidity by allowing chlorogenic acid esterase to act on a tea extract (see patent document 9); a method for producing a tea extract, characterized by extracting a tea raw material in the presence of a protease and a tannase (see patent document 10); a method for producing a tea leaf extract, characterized by subjecting tea leaves to an enzymatic decomposition extraction treatment using enzymes containing at least cellulase, hemicellulase, pectinase and protopectinase (see patent document 11); a method for extracting a tea extract, characterized by extracting tea leaves with water in the presence of a protease and further treating the resulting extract with a protease (see patent document 12); a method for producing a tea extract characterized by subjecting a tea material to enzymatic degradation treatment with a saccharide-degrading enzyme such as glucoamylase, hemicellulase, pectinase, mannanase, sucrase or α -galactosidase at the time of extraction and/or after extraction (see patent document 13); a method for producing tea extract characterized by using Pycnoporus coccineus (A.coccineus)Pycnoporus coccineus) And (2) subjecting a tea material to an enzymatic decomposition extraction treatment with a production enzyme, cellulase, hemicellulase, pectinase or protopectinase (see patent document 14).

However, although these new methods have been successful in improving taste such as sweetness, high-flavor and deliciousness and improving yield, it is not said that all useful components such as cell walls and proteins remain in the extraction residue of tea and are not all effectively utilized.

Prior art documents

Patent document

Patent document 1: japanese examined patent publication (Kokoku) No. 46-17958

Patent document 2: japanese examined patent publication No. 52-42877

Patent document 3: japanese examined patent publication No. 62-15175

Patent document 4: japanese patent laid-open publication No. 57-47465

Patent document 5: japanese examined patent publication (Kokoku) No. 1-47979

Patent document 6: japanese examined patent publication (Kokoku) No. 4-63662

Patent document 7: japanese patent No. 3157539

Patent document 8: japanese patent laid-open No. 5-328901

Patent document 9: japanese laid-open patent publication No. 11-308965

Patent document 10: japanese patent laid-open publication No. 2003-144049

Patent document 11: japanese patent laid-open publication No. 2003-210110

Patent document 12: japanese laid-open patent publication No. 2008-67631

Patent document 13: japanese laid-open patent publication No. 2008-86280

Patent document 14: japanese patent laid-open No. 2008-125477.

Disclosure of Invention

Problems to be solved by the invention

The invention aims to: provided is a method for producing a tea extract having a high sweetness, high concentration and good taste and less astringency from tea leaves, which is capable of extracting a cell wall component derived from tea leaves which has not been completely decomposed and extracted by a conventional enzyme treatment extraction method using tea leaves.

Means for solving the problems

It is considered that tea leaves contain approximately 43.9% of carbohydrates (5 th edition of food ingredient table), and most of them (approximately 30% of tea leaves) are cell wall components such as cellulose and pectin. Therefore, it is expected that a tea extract having a strong sweet taste can be obtained in a high yield by decomposing the cell wall component. However, although some degree of effect can be obtained by acting cellulase or pectinase on tea leaves, it cannot be said that the components in the cell wall can be completely utilized. Therefore, the present inventors further conducted extensive studies, and as a result, surprisingly found that: when an amylase, an enzyme preparation having polygalacturonase activity of 20000U/g or more, and a specific cellulase (i.e., a cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei) are added to tea leaves and extracted, the yield of soluble solid components derived from tea leaves is dramatically improved, sucrose, cellobiose, galacturonic acid, and the like are produced, and the obtained tea extract is rich in sweetness, taste-dense, and delicacy, thereby completing the present invention.

Accordingly, the present invention provides a method for producing a tea extract, characterized in that: a tea material is extracted by adding (A) amylase, (B) an enzyme preparation having polygalacturonase activity of 20000U/g or more, and (C) cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the method of the present invention, about 40% by mass to about 75% by mass of tea used as a raw material can be converted into a soluble solid component, and the yield of an extract from the tea raw material can be greatly improved, and the obtained tea extract contains a large amount of glucose, cellobiose, and galacturonic acid. Further, the tea extract produced by the method of the present invention is rich in sweetness, concentrated taste and deliciousness, and can impart sweetness, concentrated taste and deliciousness to tea beverages and the like or enhance sweetness, concentrated taste and deliciousness to tea beverages and the like by adding to tea beverages and the like. In addition, when the tea extract of the present invention is prepared by the enzyme treatment of the tea raw material, the viscosity in the enzyme treatment is reduced and becomes loose as the enzyme treatment proceeds, so that the step of separating the tea leaf residue from the enzyme-treated slurry becomes easy to perform. Specifically, the time required for the operations such as separation and filtration can be significantly shortened, so that the operability in the production can be improved, and the effect of reducing the production cost can be obtained even when the operation time is shortened.

Best Mode for Carrying Out The Invention

Examples of the tea used as a raw material in the method of the present invention include unfermented teas, semi-fermented teas and fermented teas obtained by processing raw leaves obtained from buds, leaves, stems and the like of tea (scientific name: Camellia sinensis (L) o.kuntze) belonging to the family Theaceae, which is a evergreen tree. Examples of the nonfermented tea include steamed nonfermented teas such as boiled tea, coarse tea, baked tea, yulu, cap tea and Tiancha, and pot-fried teas such as paddling wild tea, green willow tea and various Chinese teas; examples of the semi-fermented tea include seed tea, Tieguanyin tea, oolong tea, and the like; examples of the fermented tea include black tea, Pu' er tea, Apocynum venetum Roxb, rock tea, and the like. In addition, tea obtained by perfuming unfermented tea or semi-fermented tea with flower can also be used. Among them, green tea, oolong tea, jasmine tea and the like are particularly preferable from the viewpoint that a tea extract having a fresh and natural aroma, a sweet taste, a delicious taste and the like can be obtained.

The method of the invention is characterized in that: the tea material is extracted by adding (A) amylase, (B) an enzyme preparation having polygalacturonase activity of 20000U/g or more, and (C) a specific cellulase (i.e., cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei).

As described above, a technique of extracting a tea material by treating the tea material with pectinase, a technique of extracting a tea material by treating the tea material with cellulase, and a technique of extracting tea leaves by treating the tea leaves with a combination of pectinase and cellulase have been known before the present patent application. However, according to the present invention, when an amylase, preferably an enzyme preparation having polygalacturonase activity of 20000U/g or more and a specific cellulase (i.e., cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei) in an amount of 800U or more of polygalacturonase activity per 1g of tea material are added to the tea material as described above and the extraction treatment is performed, a surprising phenomenon that about 40% by mass to about 75% by mass of the tea material (dried tea leaves) is solubilized occurs unexpectedly, and sucrose, cellobiose, and galacturonic acid are produced along with the decomposition of cell wall components, so that sweetness, richness, taste, and deliciousness are enhanced, and a tea extract rich in flavor can be obtained in high yield.

The amylase (a) used for the enzyme treatment in the present invention is an enzyme that converts amylose and amylopectin in starch into glucose, maltose and oligosaccharide by hydrolyzing glycosidic bonds. The amylase comprises alpha-amylase, beta-amylase and glucoamylase. Alpha-amylases are enzymes that cleave the alpha-1, 4 bond of starch or glycogen irregularly, producing polysaccharides or even oligosaccharides. Beta-amylases are enzymes that break down starch or glycogen into maltose. Glucoamylase is an enzyme that breaks down the alpha-1, 4 linkage at the non-reducing end of the sugar chain to produce glucose. Among these amylases, preferred are an alpha-amylase and a glucoamylase, more preferred is a glucoamylase, and even more preferred is a combination of an alpha-amylase and a glucoamylase.

It is considered that α -amylase irregularly cleaves α -1,4 bonds in starch or glycogen and further separates glucose from the end of a molecular side chain, and therefore, glucose having a strong sweet taste is easily produced. Glucoamylase is an enzyme that decomposes α -1,4 bonds at non-reducing ends of sugar chains to produce glucose, and acts on starchy plant materials to produce glucose having a strong sweet taste, and thus has a great sweet taste enhancing effect.

As the α -amylase, commercially available products include, for example, Biozyme (ビオザイム) (registered trademark) F1OSD, A, L, amylase S "Amano (アマノ)" 35G (both of which are manufactured by Amano Enzyme Inc. (アマノ エンザイム Co.), Kokulase (コクラーゼ) (registered trademark) (Mitsubishi-Kagaku Foods Corporation (Mitsubishi chemical フーズ Co.), Sumizyme (スミチーム) (registered trademark) L (New Nissan chemical Co., Ltd.), Crystase (クライスターゼ) (registered trademark) L1, P8, SD80, T10S, コクゲン SD-A, コクゲン L (both of which are manufactured by Dazaku Kazaki Kaisho Co., Ltd.), Biotex (ビオテックス) L #3000, TS, Spitase (スピターゼ) HS, CP-40, and NaFG-404 (both of which are manufactured by Chemiex Corporation (ナガセケムテックス Co.), grindamyl (グリンドアミル) (registered trademark) A (manufactured by Danisco Japan Ltd. (ダニスコジャパン Co.), BAN, Fungamyl (ファンガミル) (registered trademark), Termamyl (ターマミル) (registered trademark), Novamyl (ノバミル) (registered trademark), Maltogenase (マルトゲナーゼ) (registered trademark), Liquozyme Supra (リコザイムスープラ), Stainzyme (ステインザイム) (registered trademark), Aquazym (アクアザイム), Thermozyme (サーモザイム) (registered trademark), Duramyl (デュラミル) (registered trademark) (both manufactured by Novozymes Japan Ltd. (ノボザイムズジャパン Co.), フクタミラーゼ (registered trademark) 30, 50, 10L, liquefying enzyme 6T, liquefying enzyme, Liquifase (リクィファーゼ) L45 (all manufactured by HBI Enzymes Inc. (エイチビィアイ Co.) VERON AX, GX, M4, ELS (all of which are manufactured by Gutter Kouchi Co., Ltd.), Uniase (ユニアーゼ) (registered trademark) BM-8 (manufactured by Yakult Pharmaceutical Industry Co., Ltd., (ヤクルト Kogyo Co.), ラタターゼ, ラタターゼ RCS, SVA, magnax (マグナックス) JW-121, Sumizyme (registered trademark) a-10, AS (all of which are manufactured by new japan chemical industry co.), Softergen (ソフターゲン) (registered trademark) 3H (Taisho Technos co., ltd. (タイショウテクノス), spectzyme (スペザイム) (registered trademark) AA, FRED, ピュラスター OxAm, ST (all of which are manufactured by Genencor Kyowa co., ltd. (ジェネンコア), ベイクザイム (registered trademark) P500 (Nihon SiberHegner k.k. (manufactured by japan シイベルヘグナー), and the like.

Further, examples of commercially available glucoamylases include グルク (registered trademark) SG, Gluzym (グルク ザ イ ム) (registered trademark) AF6, Gluzym (registered trademark) NL4.2, wine-making glucoamylase "Amano" SD (manufactured by Amano Enzyme Inc. (Tian Ye エンザイム Co., Ltd.), GODO-ANGH (manufactured by Korea-Alcohort), Kokulase (registered trademark) G2, Kokulase (registered trademark) M (manufactured by Mitsubishi-Kagaku Foods Corporation), Optidex (オプチデックス) L (manufactured by Genencor Kwa Co., manufactured by Ltd.), Sumizyme (registered trademark) SG (manufactured by Sumizyme) and Sumizyme (registered trademark) SG (manufactured by Sumizyme Co., Ltd.), Gluzyme (manufactured by Nippon chemical industries, Ltd.), Glucozyme (グルコチーム) (registered trademark) Chemymex (manufactured by Nagaku Corporation), and Novozymes (manufactured by Yog サンスーパー and Hayase Corporation), glutamase (グルターゼ) AN (HBI Enzymes inc., manufactured by Japan), unicase (registered trademark) K, Uniase (registered trademark) 2K, Uniase (registered trademark) 30, unicase (registered trademark) 60F (both of which are manufactured by Yakult Pharmaceutical Industry co., ltd., manufactured by Japan), Magnax (マグナックス) (registered trademark) JW-201 (manufactured by Japan corporation), Grindamyl (registered trademark) AG (manufactured by Danisco Japan ltd., manufactured by Japan), and the like.

The above amylases may be used alone or in combination of 2 or more. These amylases may be used in an amount of usually about 0.01 to about 1% by mass, preferably about 0.1 to about 0.5% by mass, based on the mass of the tea material.

In addition, in the enzyme treatment according to the present invention, the tea tissue can be effectively decomposed and the extraction efficiency of water-soluble components can be increased by adding the enzyme preparation (B) having a polygalacturonase activity of 20000U/g or more to 1g of the tea material in an amount of usually 800U or more, preferably 1000U to 10000U, more preferably 1500U to 5000U.

Polygalacturonase is one of pectinases. Enzymes generally classified as pectinases include polygalacturonase, pectin lyase, and pectin methylesterase. Polygalacturonase is an enzyme that hydrolyzes α -1,4 bonds of the polygalacturonic acid backbone in pectin, pectin lyase is an enzyme that decomposes α -1,4 bonds of the polygalacturonic acid backbone in pectin by a β -elimination reaction, and pectin methylesterase is an enzyme that hydrolyzes methyl esters in pectin. Pectinase is an enzyme localized at the center of an enzyme family that destroys plant tissues, and as described above, a technique of extracting tea materials by treating them with pectinase has been known before the present patent application. However, even when a tea material is subjected to an enzyme treatment with a conventional pectinase as described in, for example, the above-mentioned patent documents at a normal addition level, it is not considered that sufficient decomposition of the tea cell tissue can be achieved. Therefore, when one of polygalacturonases, pectin lyases and pectin methylesterases among pectinases is studied to find that the polygalacturonases are effective in tea-type cell tissues alone and that the cell tissues can be sufficiently decomposed by using polygalacturonases having higher activity units than those of the polygalacturonases used so far.

In the present specification, polygalacturonase activity is a value measured by a method of determining reducing sugars as an enzyme reaction product by colorimetry by allowing polygalacturonase to act on a substrate according to the Somogyi-Nelson method (ソモギーネルソン method) (J. biol. chem. 153, 375-380, 1994), and 1 unit enzyme (1U) means an amount of enzyme that produces 1. mu. mol of galacturonic acid in 1 minute.

Examples of the above pectinases include commercially available pectinases PL "Amano", pectinase G "Amano" (all of which are manufactured by Amano Enzyme Inc.), pectinase-GODO (manufactured by Nippon Kogyo Co., Ltd.), Sucrase (スクラーゼ) (registered trademark) A, N, S (all of which are manufactured by Mitsubishi-Kagaku Foods Corporation), Sucrase (registered trademark) AP-2, SPC, SPG, MC, PX, liquid Sucrase AP-2 (all of which are manufactured by Nippon chemical industries, Ltd.), pectinase XP-534 (manufactured by Nagase Corporation), Pectinex (ペクチネックス) (registered trademark), Pectinex Ultra (ペクチネックス ウ ル ト ラ) SP-L, Ultrazyme (ウルトラザイム) (registered trademark), Vinozym (ビノザイム) (registered trademark), Citorozym (シトロザイム) (registered trademark), Peelzym (ピールザイム) (registered trademark) (Novo Nordisk Bioindex Ltd. (ノボノルディスクバイオインダストリー Co., Ltd.) as described above), Cellulosin (セルロシン) (registered trademark) PC5, PE60, PEL, soluble pectinase T (HBI Enzymes Inc. as described above), pectinase SS, and pectinase HL (Yakult Pharmaceutical Industry Co., Ltd.) as described above. Among them, pectinases having particularly high polygalacturonase activity include, for example, Sumizyme AP-2, SPC and SPG (all of which are manufactured by Nippon chemical industries, Japan).

The polygalacturonase activity of a conventional commercial pectinase preparation is usually about 500U/g to about 20000U/g. Therefore, in order to add 800U to 1g of tea material, a large amount of 0.04g to 1.6g of pectinase preparation must be added to 1g of tea material. In this case, if the enzyme preparation is added in an amount of 0.06g or more, particularly 0.08g or more, based on 1g of the tea material, the excipient or other component strongly affects the tea extract, and there is a problem that the taste of the obtained tea extract becomes light, unnatural sweetness different from that of tea is imparted, and unpleasant taste is given. Therefore, a pectinase having a high activity that the polygalacturonase activity itself is 20000U/g or more can be used as it is, but in the case of a pectinase preparation having a polygalacturonase activity of less than 20000U/g, it is necessary to purify the enzyme preparation by, for example, precipitation with a water-miscible organic solvent (acetone, ethanol, etc.), isoelectric precipitation, ultrafiltration, gel filtration, etc., and recover and use a fraction having a polygalacturonase activity of 20000U/g or more.

In addition, in the method of the present invention, when cellulase derived from Trichoderma longibrachiatum (Trichoderma longibrachiatum) or Trichoderma reesei (Trichoderma reesei) is added in addition to amylase and polygalacturonase for extraction, the yield of soluble solid components from a tea leaf raw material is dramatically improved, specifically, a surprising phenomenon that about 40% by mass to about 75% by mass is soluble in the tea leaf raw material (dried tea leaves) occurs, and the following significant effects are obtained: with the decomposition of cell wall components, glucose, galacturonic acid and cellobiose are produced in large amounts, and with their increase, the taste, sweetness, high-flavor, etc. are enhanced, and a tea extract rich in flavor can be obtained in high yield.

Examples of the cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei include Cellulosin (registered trademark) T3 (manufactured by HBI Enzymes Inc.), Sumizyme (registered trademark) CS and C (both manufactured by Nippon chemical industries Co., Ltd.), cellulase SS (manufactured by Nagase Chemtex Corporation) and cellulase C (manufactured by Mitsubishi-Kagaku Foods Corporation). The amount of cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) used varies depending on the titer and the like, but is exemplified in the range of usually about 0.1U to about 200U, preferably about 0.5U to about 100U, more preferably about 1U to about 50U per 1g of tea material.

In the present invention, other carbohydrases such as hemicellulases, protopectinases, glucoamylases, glucanases, mannanases, and α -galactosidases may be further used in combination within the range where the effect of the present invention is not impaired.

The tea material usually contains sucrose in an amount of about 1 to 3%. In the present invention, as described above, the sucrose is decomposed by the action of amylase to increase glucose, but in this case, if the sucrose is decomposed into glucose and fructose by the action of sucrase, the sweetness is slightly reduced. Therefore, it is preferable in the present invention that the enzyme activity for the enzyme treatment does not substantially contain sucrase activity. Since commercially available enzyme preparations also contain other enzyme activities, the judgment of whether or not the sucrase activity is substantially contained in the enzyme preparation used can be carried out as follows: the reaction is carried out by using sucrose as a substrate, and the determination is carried out by using a glucose test strip or the like. In addition, in actual use, it can be judged whether sucrose remains in the extract.

One embodiment of the preparation of the tea extract of the present invention is shown below:

preparing 4 to 40 parts by mass of water and a 0.1 to 1% by mass ascorbic acid or sodium ascorbate solution in which the tea material is dissolved, based on 1 part by weight of the tea material, adding the tea material thereto, sterilizing at about 60 to about 121 ℃ for about 2 seconds to about 20 minutes, if necessary, and cooling. Subsequently, amylase, polygalacturonase in an amount of 500U or more per 1g of tea leaves, and (c) cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei are added, mixed uniformly, and then subjected to enzyme treatment at 20 ℃ to 60 ℃ for about 30 minutes to 24 hours. After the enzyme treatment, the enzyme is inactivated at about 60 ℃ to about 121 ℃ for about 2 seconds to about 20 minutes, then cooled, and separated by a suitable separation means such as centrifugation and filter paper filtration, whereby a clear tea extract can be obtained. The obtained tea extract can also be made into concentrated solution by appropriate concentration method according to requirement.

By the above enzyme treatment extraction, the cell tissue of the tea material is decomposed to generate a large amount of glucose, cellobiose, and galacturonic acid as compared with a tea extract which is not subjected to any enzyme treatment, and about 40% by mass to about 75% by mass of the tea used as the material can be converted into a soluble solid component.

According to the above method, the yield of solid components, the yield of glucose, the yield of cellobiose and the yield of galacturonic acid from the tea material are all increased, and as a result, the following sweet, strong and delicious tea extracts can be obtained: (a) a glucose/tannin mass ratio of 0.3 to 1.8, (b) a galacturonic acid/tannin mass ratio of 0.06 to 0.6, and (c) a tea extract having a cellobiose/tannin mass ratio of 0.08 to 0.8; preferably (a) a tea extract having a glucose/tannin mass ratio of 0.4 to 1.5, (b) a galacturonic acid/tannin mass ratio of 0.08 to 0.5, and (c) a cellobiose/tannin mass ratio of 0.10 to 0.6; more preferably, (a) the mass ratio of glucose/tannin is 0.5 to 1.2, (b) the mass ratio of galacturonic acid/tannin is 0.1 to 0.4, and (c) the mass ratio of cellobiose/tannin is 0.11 to 0.4.

It is known that glucose has a favorable sweetness and contributes to the sweetness of tea and also has an effect of masking bitterness and astringency of catechin and the like.

In addition, galacturonic acid has a thick, refreshing sour taste like high-grade tea such as matcha, and is therefore presumed to have the effects of masking bitterness and astringency, masking off-flavors, imparting a sticky feel, etc., and the increase in galacturonic acid is presumed to be an important cause for the sweetness, concentrated flavor, deliciousness, etc. of the tea extract of the present invention.

Further, it is known that cellobiose has effects of masking sour taste, masking bitter taste, masking off-flavor, imparting a sticky feeling (ボディー feeling), etc., in addition to a weak sweet taste, and it is presumed that an increase in cellobiose is an important cause for sweet taste, strong taste, deliciousness, etc., of the tea extract produced according to the present invention.

The tea extract of the present invention can be stored for a long period of time by heat sterilization after or before filling in a container, as required.

The tea extract obtained by the method of the present invention may be used as it is in a liquid state, but may be made into a powder by adding an excipient such as dextrin, chemical starch, cyclodextrin, gum arabic or the like as needed.

The present invention will be described more specifically with reference to examples and comparative examples.

Examples

Reference example 1 measurement of polygalacturonase Activity (Somogyi-Nelson method (ソモギーネルソン method): see J. biol. chem. 153, 375-

To 0.9ml of 50mM acetate buffer (pH4.5) containing 1% polygalacturonic acid was added 0.1ml of an appropriate (appropriate) dilution of the enzyme solution. The mixed solution was reacted at 45 ℃ for an appropriate time, then heated in a boiling water bath for 10 minutes to inactivate the enzyme, and the reaction solution was prepared by ice-cooling. To 0.3ml of the reaction solution, 0.3ml of Somogyi copper reagent was added, the mixture was heated in a boiling water bath for 10 minutes under ice-cooling, 0.3ml of Nelson reagent was added, the mixture was sufficiently stirred in a tube mixer, 3ml of ion-exchanged water was further added, and the mixture was sufficiently stirred in a tube mixer. The solution was treated with a centrifuge at 9000 revolutions for 3 minutes, and the absorbance (Abs.) of the supernatant at 500nm was measured. On the other hand, exactly the same procedure as described above was carried out using a solution obtained by heat-inactivating an appropriate (appropriate) diluted solution of the enzyme solution in advance, and the blank absorbance was obtained. The number of μmol of galactobiosate produced by 1g of enzyme in 1 minute was calculated from the enzyme concentration, enzyme reaction time and absorbance, and was defined as a unit (U) per 1g of enzyme.

Measured enzyme and polygalacturonase activity measurements:

cellulosin PE60 (manufactured by HBI Enzymes Inc.): 20600U/g

Sumizyme AP2 (New Nippon chemical industry Co., Ltd.): 12400U/g

Sumizyme MC (New Nissan chemical industries Co., Ltd.): 1690U/g

Sucrase N (manufactured by Mitsubishi-Kagaku Foods Corporation): 4550U/g.

Reference example 2

100g of Sumizyme AP2 (manufactured by Nippon chemical industries, Ltd.) (polygalacturonase activity obtained by the above measurement: 12400U/g) was dissolved in 1000g of ion-exchanged water, and subjected to ultrafiltration concentration using Vivaflow (ビバフロー) (registered trademark) 50VF05P2 (molecular weight isolate 30,000: Sartorius Co., Ltd., (manufactured by ザルトリウス)), 30ml of the non-passing fraction was recovered, followed by freeze-drying to obtain reference 2 (12.0 g: polygalacturonase activity obtained by the above measurement: 86500U/g).

Example 1

To a solution obtained by dissolving 0.6g of sodium ascorbate in 900g of soft water was added 100g of oolong tea leaves (second-grade narcissus (Y-302), a raw material obtained by pulverizing tea leaves produced in fujian province with a mixer), sterilized at 80 ℃ for 5 minutes, and cooled to 45 ℃. To this were added 2.0g of Sumizyme (glucoamylase available from Nippon chemical Co., Ltd.), 2.4g of reference 2 (polygalacturonase activity was 2076U as determined above with respect to 1g of tea leaves) and 0.25g of Sumizyme C (cellulase derived from Trichoderma longibrachiatum available from Nippon chemical Co., Ltd.: 1500U/g), and the mixture was stirred for 15 minutes. Then, the enzyme treatment was carried out at 40 ℃ for 8 hours. After the enzyme treatment, the tea leaves were sterilized at 90 ℃ for 10 minutes, cooled to 30 ℃ and then removed of solid matter from the tea leaves with a dry cloth, and then suction filtration was performed under a constant pressure (reduced pressure of 13.33KPa) using a Nu collecting filter in which 10g of cellulose powder was previously coated on No.2 filter paper (8cm) to obtain 834g of a clear extract (required time for filtration: 3 minutes 21 seconds). Concentrating the extractive solution under reduced pressure to obtain Bx35 ° concentrated solution. The concentrated solution was heat-sterilized at 95 ℃ for 30 seconds, filled in a closed container, and then rapidly cooled to normal temperature to obtain an oolong tea extract (157.1g) of the present invention product 1.

Example 2

Completely the same operation as in example 1 (filtration time: 4 minutes 03 seconds) was carried out except that in example 1, 2.0g of Gluczym AF6 (glucoamylase manufactured by Amano Enzyme Inc.) was used in place of 2.0g of Sumizyme, and 0.25g of Cellulosin (registered trademark) T3 (cellulase derived from Trichoderma reesei manufactured by エイチビィアイ: 2600U/g) was used in place of 0.25g of Sumizyme C, to obtain invention product 2 (158.8 g).

Example 3

The same operations AS in example 1 (filtration time: 4 minutes and 24 seconds) were carried out except that in example 1, 2.0g of Sumizyme AS (α -amylase manufactured by Nippon chemical industries) was used in place of 2.0g of Sumizyme and 0.25g of cellulase SS (cellulase derived from Trichoderma reesei manufactured by Nagase Chemtex Corporation) was used in place of 0.25g of Sumizyme C, to obtain product 3 of the present invention (154.3 g).

Example 4

The same operations as in example 1 (filtration time: 4 minutes 56 seconds) were carried out except that 2.0g of Crystase P8 (α -amylase manufactured by Amano Enzyme Inc.) was added in place of 2.0g of Sumizyme in example 1 to obtain invention product 4 (158.5 g).

Example 5

The same operation as in example 1 (filtration time: 4 minutes 36 seconds) was carried out except that in example 1, 2.0g of Sumizyme L (α -amylase manufactured by Nippon chemical industries) was used in place of 2.0g of Sumizyme and that in example 1, Sucrase C (cellulase derived from Trichoderma longibrachiatum manufactured by Mitsubishi-Kagaku Foods Corporation: 3000U/g) was used in place of 0.25g of Sumizyme C, to obtain invention 5 (156.2 g).

Example 6

Completely the same operation as in example 1 (filtration time: 4 minutes and 47 seconds) was carried out except that 2.5g (polygalacturonase activity measured as 515U/g relative to 1g of tea leaves) of Cellulosin PE60 (manufactured by HBI Enzymes Inc.) was used in place of reference 2 (2.4g) in example 1 to obtain invention product 6 (155.7 g).

Example 7

The same operations as in example 1 (filtration time: 4 minutes 58 seconds) were carried out except that in example 1, 2.4g was replaced with 0.8g of reference 2 (the polygalacturonase activity measured as 692U relative to 1g of tea leaves) to obtain inventive product 7 (143.4 g).

Reference example 3

150g of Sumizyme MC (manufactured by Nippon chemical Co., Ltd.) (polygalacturonase activity obtained by the above measurement: 1690U/g) was dissolved in 1500g of ion-exchanged water, washed, and the precipitate was collected by centrifugation (4,500 Xg, 5 minutes), followed by freeze-drying to obtain reference product 3 (9.8g, polygalacturonase activity obtained by the above measurement: 20770U/g).

Example 8

The same operation as in example 1 (filtration time: 4 minutes and 29 seconds) was carried out except that 9.7g of reference 3 (polygalacturonase activity 2015U obtained by the above-described measurement was added to example 1 in place of reference 2 (2.4g) to obtain invention 8 (153.2).

Reference example 4

100g (polygalacturonase activity obtained by the above measurement: 4550U/g) of Sucrase N (manufactured by Mitsubishi-Kagaku Foods Corporation) was dissolved in 1000g of ion-exchanged water, and subjected to ultrafiltration concentration using Vivaflow (ビバフロー) (registered trademark) 50VF05P2 (isolation molecular weight 30,000: Sartorius Co., Ltd.), 25ml of an unreacted portion was recovered, and further subjected to freeze-drying to obtain reference 4 (10.0g, polygalacturonase activity obtained by the above measurement: 32,000U/g).

Example 9

The same operation as in example 1 (filtration time: 4 minutes 45 seconds) was carried out except that 6.24g of reference 4 (the polygalacturonase activity measured in the above manner was 1997U/g relative to 1g of tea leaves) was added in place of reference 2 (2.4g) in example 1 to obtain inventive product 9 (156.7 g).

Example 10

The same operation as in example 1 (filtration time: 3 minutes and 54 seconds) was carried out except that 100g of Tieguanyin (tertiary Tieguanyin (K-103): raw material obtained by pulverizing Fujian province tea leaves with a mixer) was used in example 1 instead of 100g of oolong tea (secondary narcissus (Y-302): raw material obtained by pulverizing Fujian province tea leaves with a mixer), to obtain inventive product 10 (158.9 g).

Example 11

The same operation as in example 1 (filtration time: 4 minutes and 43 seconds) was carried out except that 100g of green tea leaves (steaming process of China) was used in example 1 instead of 100g of oolong tea leaves (Y-302: raw material obtained by crushing tea leaves produced in Fujian province by a mixer), thereby obtaining inventive product 11 (213.2 g).

Comparative example 1

Exactly the same operation as in example 1 was carried out (filtration time: 12 minutes and 13 seconds) except that no enzyme was used in example 1, to obtain comparative product 1 (87.8 g).

Comparative example 2

Comparative product 2 (88.5g) was prepared in the same manner as in example 10 (filtration time: 11 minutes 44 seconds) except that no enzyme was used in example 10.

Comparative example 3

Comparative product 3 (91.4g) was prepared in the same manner as in example 11 except that in example 11, no enzyme was used at all (the time required for filtration was 11 minutes and 24 seconds).

Comparative example 4

Exactly the same operation as in example 1 (filtration time: 7 minutes 13 seconds) was carried out except that in example 1, 0.25g of Cellulosin AC40 (cellulase derived from Aspergillus niger manufactured by HBI Enzymes Inc.) was used in place of 0.25g of Sumizyme C, to obtain comparative product 4 (134.1 g).

Comparative example 5

Exactly the same operation as in example 1 (filtration time: 7 minutes 26 seconds) was carried out except that 0.25g of cellulase T "Amano" 4 (Trichoderma viride-derived cellulase manufactured by Amano Enzyme Inc.) was used in place of 0.25g of Sumizyme C in example 1, to obtain comparative product 5 (137.2 g).

Comparative example 6

Exactly the same operation as in example 1 (filtration time: 7 minutes 55 seconds) was carried out except that 0.25g of cellulase XP425 (cellulase derived from Trichoderma viride manufactured by Nagase Chemtex Corporation) was used in example 1 in place of 0.25g of Sumizyme C, to obtain comparative product 6 (134.2 g).

Comparative example 7

Exactly the same operation as in example 1 (filtration time: 8 minutes 13 seconds) was carried out except that in example 1, 0.25g of Cellulesnagase (セルレースナガセ) (Aspergillus niger-derived cellulase manufactured by Nagase Chemtex Corporation) was used in place of 0.25g of Sumizyme C, to obtain comparative product 7 (129.7 g).

Comparative example 8

Comparative product 8 (130.8g) was prepared in the same manner as in example 1 except that 0.25g of Sumizyme AC (cellulase derived from Aspergillus niger, manufactured by Nippon chemical Co., Ltd.) was used in place of 0.25g of Sumizyme C in example 1 (filtration time: 7 minutes and 47 seconds).

Comparative example 9

Comparative product 9 (132.5g) was prepared in the same manner as in example 1 except that the amount of reference product 2 used in example 1 was changed to 2.4g, instead of 0.4g (the polygalacturonase activity measured as described above was 346U relative to 1g of tea leaves).

Comparative example 10

Comparative product 10 (129.7g) was prepared in the same manner as in example 1 (filtration time: 7 minutes 29 seconds) except that 2.0g of Sumizyme MC (manufactured by Nippon chemical Co., Ltd.) having a polygalacturonase activity of 33.8U/g as measured above was used in example 1 in place of reference product 2 (2.4 g).

Comparative example 11

Exactly the same operation as in example 1 (6 minutes 47 seconds required for filtration) was carried out except that 2.0g of Sucrase N (manufactured by Mitsubishi-Kagaku Foods Corporation) having a polygalacturonase activity of 91U/g as determined above was used in example 1 in place of reference 2 (2.4g) to obtain comparative product 11 (138.3 g).

Comparative examples 12 to 14 (examples in which polygalacturonase activity was 800U or more per 1g of tea leaves by using a large amount of commercially available pectinase)

Comparative examples 12 to 14 were prepared in exactly the same manner as in example 1 except that 8.0g (992U/g polygalacturonase activity measured above relative to 1g of tea leaves) of Sumizyme AP2 (New Nippon chemical Co., Ltd.), 50.0g (845U/g polygalacturonase activity measured above relative to 1g of tea leaves) of Sumizyme MC (New Nippon chemical Co., Ltd.) and 20g (910U/g polygalacturonase activity measured above relative to 1g of tea leaves) of Sucrase N (Mitsubishi-Kagaku Foods Corporation) were used in place of reference 2 (2.4g) in example 1 (the time required for filtration and the harvest yield were shown in Table 1 below together with other measured values).

Analysis of composition

The concentrations (% as a mass standard) of tannin, amino acid, glucose, galacturonic acid, cellobiose, and sucrose were measured for the products 1 to 11 of the present invention and the comparative products 1 to 14.

Measurement method

Amino acids: automatic amino acid analyzer

Tannin: iron tartrate process

Glucose, cellobiose, galacturonic acid, sucrose: high Performance Liquid Chromatography (HPLC)

The amounts of the tea material-derived products of the present invention 1 to 11 and the comparative products 1 to 14, the measured values (concentrations) of the respective components, and the time required for filtration are shown in Table 1 below.

[ Table 1]

TABLE 1

As shown in table 1, the products 1 to 11 and the comparative products 12 to 14, in which the tea material was extracted with the addition of amylase and the polygalacturonase and the cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) per 1g of the tea material, significantly reduced the filtration time and significantly improved the operability, compared with the comparative products 4 to 8 in which the enzyme was not used at all, and the cellulase derived from microorganisms other than Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) alone was replaced with the cellulase, respectively, and the comparative products 9 to 11, in which the polygalacturonase was less than 800U per 1g of tea material.

The reduction of the filtration time is not a great difference in units in the small-amount production, but is generally a rate-limiting step that limits the overall operation time in the industrial production of extracts, and is expected to be significantly improved when a large-amount (several tons to several tens tons) of extracts are industrially produced.

In addition, as shown in table 1, the compositions of the present invention products 1 to 11 and comparative products 12 to 14, which were extracted by adding amylase, polygalacturonase in an amount of 800U or more per 1g of tea material, and cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei), increased the yield of the extract by about 2 times and increased the concentrations of glucose, galacturonic acid, and cellobiose by a large amount, as compared with comparative products 1 to 3, which did not use any enzyme at all.

The glucose concentration values of comparative products 1 to 3, which did not use any enzyme at all, were low and only 0.24 to 0.65% by mass, but the glucose concentrations of products 1 to 11 according to the present invention and comparative products 4 to 11, which were extracted by adding amylase, polygalacturonase at 800U or more per 1g of tea material, and cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Amyloderma reesei) to tea leaves were 3.60 to 5.37% by mass, and the amounts of glucose were about 10 to 20 times the amounts of the untreated products.

In addition, the glucose concentration of comparison products 12 to 14, which are obtained by adding amylase, an enzyme preparation having polygalacturonase activity of less than 20000U/g (a commercially available pectinase preparation), polygalacturonase having 800U or more per 1g of tea material, and cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) to tea leaves is 8.13 to 17.1% by mass, and the glucose content of the untreated product is about 30 to 70 times that of the untreated product. However, since the amount of starch in dried tea leaves is extremely large compared with that predicted from the amount of starch (usually about 0.8 to 2.5% by mass), it is estimated that the starch is derived from a decomposition product of a large amount of a polygalacturonase preparation excipient (dextrin).

The comparative products 1 to 3 which did not use any enzyme contained no galacturonic acid, and the products 1 to 11 of the present invention and the comparative products 4 to 14 which acted on polygalacturonase contained a large amount of galacturonic acid. Further, the amount of polygalacturonase produced increased with increasing activity units of polygalacturonase relative to tea leaves (see products 1, 6, 7 to 9 of the present invention and comparative products 9 to 11).

In comparative products 10 and 11 using commonly added amounts (2.0% relative to tea leaves) of commonly used pectinases (Sumizyme MC, Sucrase N) so far, the galacturonic acid concentrations were 0.153% by mass and 0.219% by mass, respectively, and the concentrations were low, but in inventive products 8 and 9, which were prepared by purifying these enzymes by isoelectric precipitation or ultrafiltration concentration to improve polygalacturonase activity, the galacturonic acid concentrations were 1.125% by mass and 1.323% by mass, respectively, and reached as high a level as in inventive product 1. Therefore, it is known that in order to produce galacturonic acid at a high concentration, a large amount of polygalacturonase activity units must be added to some extent relative to tea leaves.

Comparative products 1 to 3 which did not use any enzyme contained no cellobiose at all, and the products 1 to 11 and comparative products 4 to 14 which acted on cellulase contained a large amount of cellobiose. The cellobiose concentrations of the products 1 to 11 of the present invention and the comparative products 9 to 14 extracted by adding cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) as cellulase were about 1% by mass, while the concentrations of the comparative products 4 to 8 using cellulase derived from Aspergillus niger or Trichoderma viride as cellulase were low, and were only about 0.3 to 0.4% by mass.

It can be seen that the tannin concentration tends to decrease with increasing yield of the extract. This is considered to be because most of the tannins in tea leaves are extracted by hot water extraction, and although the absolute amount thereof is limited, when the yield of tea extract is increased, the tannins are relatively diluted by the above-mentioned decomposition and extraction of sugars.

Sucrose was contained in the amounts of about 3.3 to 4.3% by mass in comparative examples 1 to 3 which were not subjected to any enzyme treatment at all, and in all of the enzyme-treated products, the amount was substantially 2% by mass or more, but the amounts of inventive products 5 and 9 and comparative products 8, 11 and 14 were less than 1% by mass. Therefore, the reason for this is presumed to be: since the enzymes used for the preparation of these tea extracts (the present invention products or comparative products) having low sucrose concentrations contained sucrase activity, the presence or absence of sucrase activity was determined for the enzymes used in table 1.

Example 12 (determination of the Presence or absence of sucrase Activity for various enzymes)

0.005g of the enzyme was dissolved in 100ml of a 0.5% aqueous solution of sucrose, and the mixture was left at 38 ℃ for 1 day and night, and the production of glucose in the reaction solution was determined using glucose paper (ウリエース (registered trademark) Ga (manufactured by Taylolmog) according to the criteria of less than 50mg/100ml,. + -. 50mg/100ml, + -. 100mg/100ml, + -. 500mg/100ml, + -. 2000mg/100ml, and the results are shown in Table 2 below.

[ Table 2]

Sucrase activity of the enzymes used in Table 2

As shown in Table 2, Sucrase activity was seen in Sumizyme L, Sucrase N and Sumizyme AC. Therefore, the sucrose concentration of inventive products 5, 9 and comparative products 8, 11 of less than 1% is caused by the sucrase activity among the enzymes used therein.

Evaluation of Functionality

The products 1 to 11 of the present invention and the comparative products 1 to 14 were diluted to 160 times (bx0.3 °) with ion-exchanged water, and then subjected to functional evaluation by 10 fully trained test persons. The evaluation methods were that the bitterness, sweetness, deliciousness, and balance were very good: 10 minutes, good: 8 min, slightly better: 6 minutes, slightly worse: 4 min, difference: 2 points, very poor: score 0 was evaluated for functionality and the comment was recorded. The average score and the average content of the comments are shown in the following table 3.

[ Table 3]

TABLE 3

As shown in table 3, comparative products 1 to 3, which did not use any enzyme at all, obtained evaluations of the tea products for their delicious taste, weak sweet taste, strong bitterness and astringency, and low evaluations of bitterness and astringency, sweet taste, delicious taste, and balance.

On the other hand, products 1 to 11 of the present invention, in which amylase was added and polygalacturonase and cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) were extracted per 1g of tea material, had strong taste, sweetness and dense taste of tea, weak and mild bitterness and astringency, and good taste balance as a whole, and were evaluated extremely high.

On the other hand, comparative examples 4 to 7 in which the cellulase derived from Trichoderma longibrachiatum of invention product 1 was replaced with the cellulase derived from Aspergillus niger or the cellulase derived from Trichoderma viride were evaluated as follows: although the oolong tea had a certain degree of taste and sweetness, it had a slightly strong bitterness and astringency and a slightly poor balance, and the evaluation was slightly inferior to that of the present invention. In addition, comparative product 8 in which cellulase derived from Trichoderma longibrachiatum of product 1 of the present invention was replaced with Sumizyme AC belonging to cellulase derived from Aspergillus niger was similarly evaluated as follows: although the oolong tea is delicious and sweet to some extent, it is strong and remarkable in bitterness and astringency, and poor in balance, and the evaluation is inferior to that of the present invention.

In addition, comparative products 9 and 10 in which the amount of polygalacturonase added to the product 1 of the present invention was reduced or replaced with Sumizyme MC having low polygalacturonase activity were evaluated as follows: although the oolong tea is slightly palatable and sweet, it is slightly astringent and has a slightly poor balance, and the evaluation is inferior to the product of the present invention. Similarly, comparative product 11 in which polygalacturonase in product 1 of the present invention was replaced with Sucrase N having low polygalacturonase activity was evaluated as follows: although the oolong tea is slightly tasty and sweet to some extent, it is slightly noticeable and has a strong bitter taste, a poor balance, and is inferior to the present invention.

Furthermore, comparative extracts 12 to 14 obtained by adding amylase to tea leaves, an enzyme preparation having polygalacturonase activity of less than 20000U/g in an amount of 800U or more per 1g of tea leaves (commercially available pectinase preparation), and cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei (Trichoderma reesei) were evaluated as follows: although the taste and sweetness of oolong tea can be perceived to some extent, the sweetness and foreign taste different from tea can be strongly perceived, and the balance is poor.

Ratio between the ingredients

Tannin is a bitter component of tea, but in tea beverages, tannin is an important component for brewing taste by balancing its taste and sweetness with other components (i.e., amino acids or sugars). On the other hand, it is known that glucose, which is an added component in the tea extract of the present invention, has a favorable sweetness, contributes to the sweetness of tea, and has an effect of masking bitterness and astringency possessed by catechin and the like. In addition, galacturonic acid has a thick, refreshing sour taste like high-grade tea such as matcha, and is therefore presumed to have the effects of masking bitterness and astringency, masking off-flavors, imparting a sticky feel, etc., and the increase in galacturonic acid is presumed to be an important cause for the sweetness, strong flavor, deliciousness, etc. of the tea extract produced according to the present invention. Further, it is known that cellobiose has effects of masking sour taste, masking bitter taste, masking off-flavor, imparting a sticky feeling, etc., in addition to weak sweet taste, and therefore, it is presumed that an increase in cellobiose is also an important cause in terms of sweet taste, strong taste, deliciousness, etc., of the tea extract produced according to the present invention.

As is clear from the results shown in table 1, since the present invention contains relatively more glucose, galacturonic acid and cellobiose than other components, the mass ratio of (a) glucose/tannin, (b) galacturonic acid/tannin, (c) cellobiose/tannin and sucrose/tannin were calculated for the present invention products 1 to 11 and the comparative products 1 to 14. The results are shown in Table 4 below.

[ Table 4]

TABLE 4

As shown in Table 4, in the case of the products of the present invention 1 to 4, 6 to 8, 10 and 11 having extremely high taste evaluation and the products of the present invention 5 and 9 having only second highest evaluation than these products, (a) the mass ratio of glucose/tannin is 0.5 to 1.2, (b) the mass ratio of galacturonic acid/tannin is 0.10 to 0.4, and (c) the mass ratio of cellobiose/tannin is in the range of 0.15 to 0.4.

In addition, in the present invention products 1 to 4, 6 to 8, 10 and 11, which are extremely high in taste evaluation, the (d) sucrose/tannin mass ratio is in the range of 0.4 to 0.6, and the present invention products 5 and 9, which are slightly inferior to these products, are evaluated to be low values of less than 0.1. The reason is considered to be: since sucrose contained in tea leaves itself is decomposed into glucose and fructose by the sucrase activity of the enzyme used in the products 5 and 9 of the present invention, the total sweetness is reduced although it is small.

In addition, in comparative examples 12 to 14, which were evaluated to have a balance of poor balance between the sweetness and the unpleasant taste of oolong tea, although the taste and the sweetness of oolong tea could be perceived to some extent, the mass ratio of (a) glucose/tannin was extremely high, being 1.8 to 6.5, but since a large amount of an enzyme preparation (polygalacturonase) was used, it was presumed that glucose contained therein was generated by decomposition of an excipient (dextrin) contained in the enzyme preparation due to the action of amylase.

On the other hand, in comparative examples 4 to 7, which were evaluated for taste with slightly strong bitterness and astringency and a slightly poor balance, although some degree of taste and sweetness of oolong tea could be perceived, the mass ratio of cellobiose/tannin of (c) was less than 0.08. In addition, the mass ratio of galacturonic acid/tannin (b) was less than 0.06 for comparative products 9-11, which were evaluated for taste with slightly strong bitterness and astringency and a slightly poor balance, although some degree of palatability and sweetness of oolong tea were perceived. Further, of these comparative examples, comparative examples 4 to 7 and 9 to 10 which were relatively well evaluated, but the evaluation was slightly inferior to these comparative examples, in which (d) the sucrose/tannin mass ratio was in the range of 0.4 to 0.6; comparative products 8 and 11, which were evaluated to have strong and remarkable bitterness and astringency and poor balance, were less than 0.16.

Therefore, it is considered that the tea extract produced according to the present invention is sweet, concentrated, delicious, etc. due to these differences.

In addition, as the range of the numerical value, it is understood from the above examples that the following conditions are satisfied, and the taste by the effect of the present invention is obtained: (a) a glucose/tannin mass ratio of 0.3 to 1.8, (b) a galacturonic acid/tannin mass ratio of 0.06 to 0.6, and (c) a cellobiose/tannin mass ratio of 0.08 to 0.8; preferably, (a) the mass ratio of glucose to tannin is 0.4-1.5, (b) the mass ratio of galacturonic acid to tannin is 0.08-0.5, and (c) the mass ratio of cellobiose to tannin is 0.10-0.6; more preferably, (a) the mass ratio of glucose/tannin is 0.5 to 1.2, (b) the mass ratio of galacturonic acid/tannin is 0.1 to 0.4, and (c) the mass ratio of cellobiose/tannin is 0.11 to 0.4.

Claims (5)

1. A method for producing a tea extract, characterized by adding (A) amylase, (B) an enzyme preparation having a polygalacturonase activity of 20000U/g or more, and (C) cellulase derived from Trichoderma longibrachiatum or Trichoderma reesei to extract a tea material.

2. The method of claim 1, wherein the tea material is green tea, oolong tea or jasmine tea.

3. The method according to claim 1 or 2, wherein the amylase (A) is added in an amount of 0.01 to 1 wt% based on the tea material.

4. The method according to claim 1 or 2, wherein the enzyme preparation (B) having polygalacturonase activity is added in an amount of 800U or more per 1g of the tea material.

5. The method according to claim 1 or 2, wherein the cellulase (C) derived from Trichoderma longibrachiatum or Trichoderma reesei is added in a range of 0.1U to 200U per 1g of the tea material.