JP2004113090A - Fermented tea-leaf extract and method for producing fermented tea beverage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently obtain fermented tea-leaf extract having body taste and flavor while having slight bitterness and astringency through carrying out fermentation of fresh tea leaves (tannic oxidation reaction) and aqueous extraction of soluble solid other than tannin derived from tea leaves in a single process; and to provide a method for producing fermented tea-leaf extract by which the flavor or color of the fermented tea-leaf extract can be regulated at will by altering fermentation (tannic oxidation reaction) time. <P>SOLUTION: The fermented tea-leaf extract is produced in a single process comprising mixing crushed but unwithered fresh tea leaves with a solution of tea-leaf organization breaking enzyme, fermenting the mixture (tannic oxidation reaction), treating the fermented mixture with the tea-leaf organization breaking enzyme, and extracting the tea leaves. <P>COPYRIGHT: (C)2004,JPO

Description

【０１２８】
［適性スラリー発酵温度の検討］
次に、上記実施例１、２、３と同様にしてヘミセルラーゼ（天野エンザイム株式会社販売、商品名ヘミセルラーゼ「アマノ」９０、Ａｓｐ．ｎｉｇｅｒ由来）０．１重量部を使用する場合の適正処理温度を検討した結果を表２に示す。
【０１２９】
なお、酵素処理時間は、各３時間とした。
【０１３０】
【表２】

【０１３１】
表２の結果から明らかなように２０℃以下では茶葉由来の可溶性固形分の抽出効率が小さく、さらに６０℃以上になると同じく茶葉由来の可溶性固形分の抽出効率が小さいことが分かり、生茶葉をヘミセルラーゼ（天野エンザイム株式会社販売、商品名ヘミセルラーゼ「アマノ」９０、Ａｓｐ．ｎｉｇｅｒ由来）による茶葉組織破壊を伴う発酵茶葉抽出処理する温度は、２０〜６０℃、好ましくは３５〜５５℃が望ましいことが判明した。
【０１３２】
【発明の効果】
本発明によれば、嗜好性に応じて、破砕処理した生茶葉の発酵（タンニン酸化反応）処理時間を変えることで、任意の風味や色合いを有する発酵茶飲料を得ることができる。また本発明によれば、苦渋味が少なく、コクと旨味の良好な発酵茶飲料を効率的に得ることができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a method for producing a fermented tea leaf extract used for fermented tea beverages such as cans and plastic bottles for soft drinks having a reduced bitterness and richness and umami, and a fermented tea using the obtained fermented tea leaf extract. The present invention relates to a method for producing a beverage.
[0002]
[Prior art]
As a general method of obtaining fermented tea leaves from raw tea leaves, as is known, a method of obtaining tea leaf products such as oolong tea and black tea by wiping, kneading, fermenting (tannin oxidation reaction), and heating and drying the picked raw tea leaves. It has been known.
[0003]
Further, in order to obtain a fermented tea leaf extract from these tea leaf products, it is usual to obtain the fermented tea leaves by throwing the obtained fermented tea leaves into warm water or hot water and extracting the fermented tea leaves.
[0004]
On the other hand, as a method of directly obtaining a fermented tea leaf extract from fresh tea leaves, a slurry fermentation method in which fermentation of fresh tea leaves and extraction of fermented tea can be performed in a single step has been conventionally known. That is, the raw tea leaves or withered tea leaves are crushed, and water is added thereto to form a suspension aqueous solution or slurry, and then fermentation (tannin oxidation reaction) at any temperature and time suitable for fermentation (tannin oxidation reaction). After that, the tea leaves are filtered to obtain a fermented tea leaf extract.
[0005]
In recent years, since bitter-tasting strong tea beverages tend to be shunned mainly by young people, increasing the ratio of soluble solids other than tannin derived from tea leaves to tannin, a bitter-tasting component, makes the umami taste stronger, At present, many tea beverages with reduced bitterness are manufactured and sold.
[0006]
However, the above-mentioned slurry fermentation method has an advantage that fermentation (tannin oxidation reaction) and water extraction are simultaneously performed to shorten the step of obtaining fermented tea, but soluble nitrogen compounds other than tannin derived from tea leaves, soluble carbohydrates, and the like. No consideration has been given to the extraction to increase taste and umami by increasing the proportion of soluble solids such as taste components, so that fermentation (tannin oxidation reaction) is performed efficiently and tannins other than tea leaf-derived tannins are used. It is required to study an efficient water extraction method for soluble solids in water.
[0007]
As an efficient water extraction method for soluble solids other than tannins derived from tea leaves, a method in which soluble solids derived from tea leaves are extracted as much as possible with high-temperature water is considered. Polyphenol oxidase, which is an oxidase in tea leaves involved in tannin oxidation reaction), is not suitable because of heat deactivation. Conversely, a method of suppressing the extraction of tannin with low-temperature water and extracting as much as possible soluble solids other than tannin derived from tea leaves with water can be considered. However, when extracting at low temperature, fermentation (tannin oxidation reaction) There is a disadvantage that sufficient fermentation (tannin oxidation reaction) is not performed because the polyphenol oxidase activity in the tea leaves involved is low.
[0008]
For this reason, many methods have been proposed for enzymatically decomposing tea leaves to increase the solid content extracted from the tea leaves.
[0009]
For example, Patent Document 1 proposes a method of increasing tea components in low-temperature extraction by adding cellulase and hemicellulase and performing enzyme treatment at 45 ° C. for 20 hours, which is described in this patent. Even for fresh leaves, oxidizing enzymes (polyphenol oxidase) are destroyed at 100 ° C., and there is no mention of fermentation (tannin oxidation reaction).
[0010]
Patent Document 2 proposes a method in which basidiomycete-derived polyphenol oxidase is sprayed and adhered to tea leaves at the time of wiping and kneading of fresh tea leaves to further promote fermentation (tannin oxidation reaction). It does not mention efficient water extraction of other soluble solids.
[0011]
Further, Patent Document 3 proposes a method of increasing tea components in extraction at 40 ° C. for 5 hours by adding cellulase and protopectinase (plant tissue disintegrating enzyme) to green tea in addition to green tea and black tea. However, no mention is made of fermentation (tannin oxidation reaction).
[0012]
On the other hand, in Patent Document 4, an extract obtained by slurry fermentation of an extract from black tea and fresh tea leaves is subjected to ion exchange treatment to remove cations, and a calcium compound is added to the extract to be treated with hard water. Although a method that sometimes does not cause turbidity is proposed, it does not mention efficient water extraction of soluble solids other than tannin derived from tea leaves.
[0013]
Patent Document 5 proposes adding a microorganism-derived polyphenol oxidase to a green tea leaf extract in which an oxidase (polyphenol oxidase) is inactivated to obtain a black tea liquor. Therefore, there is a clear difference in the technical content from the method of simultaneously performing fermentation (tannin oxidation reaction) and water extraction.
[0014]
Similarly, Patent Document 6 proposes a method in which an oxygen-containing gas is blown into a slurry fermentation liquid in order to more efficiently advance fermentation (tannin oxidation reaction) in slurry fermentation. It does not refer to efficient water extraction for minutes.
[0015]
Further, Patent Document 7 proposes a method of obtaining a high content of theaflavin by regulating the pH of a tea leaf suspension below the natural pH when slurry fermentation of raw tea leaves is performed. It does not mention efficient water extraction of other soluble solids.
[0016]
In Patent Document 8, after contacting fresh tea leaves with tannase (tannin-degrading enzyme), and then heating and drying to obtain dried green tea leaves, contacting fresh tea leaves with tannase (tannin-degrading enzyme) followed by fermentation ( Tannin oxidation reaction) and then heating and drying to obtain dried black tea leaves. Both are said to be dry black tea leaves that can be extracted with cold water. Raw tea leaves are fermented by slurry fermentation (tannin oxidation reaction). There is a clear difference in the technical content from the method of simultaneously performing water extraction and water extraction.
[0017]
Next, Patent Document 9 proposes a method in which a hydrogen peroxide solution is added to a slurry fermentation solution at a constant rate in order to efficiently promote fermentation (tannin oxidation reaction) in slurry fermentation of fresh tea leaves. This also does not refer to efficient water extraction of soluble solids other than tannins derived from tea leaves.
[0018]
Patent Document 10 proposes that fermentation (tannin oxidation reaction) can be promoted by freezing and thawing fresh tea leaves, but the same promoting effect can be found by crushing fresh tea leaves. is there.
[0019]
Similarly, in Patent Document 11, in the process of freeze-drying a black tea extract to obtain powdered black tea, black tea leaves withered (coarsely fermented) are ground and crushed under the addition of an anti-turbidity enzyme and water, and then crushed at a predetermined temperature. A method has been proposed in which fermentation is carried out for a period of time, followed by freezing and thawing, followed by the addition of hot water, stirring and solid-liquid separation of the dehydrated extract to obtain a black tea by freeze-drying the obtained clear liquid. After two-stage fermentation, fresh non-fermented (non-tannin oxidation reaction) raw tea leaves are withered (coarse fermentation), then crushed, crushed and re-fermented. A manufacturing method that involves a complicated process that is clearly different from the conventional fermentation of raw tea leaves before wilt and the extraction process of fermented tea in a single process, in which hot water is added after thawing and extraction is performed. I have to say. Although enzymes other than polyphenol oxidase are added as anti-turbidity enzymes, it does not mention efficient water extraction of soluble solids other than tannins derived from tea leaves.
[0020]
On the other hand, in Patent Document 12, in the green tea production process, the place where the raw tea leaves are steamed to deactivate the polyphenol oxidase by heating is partially steamed to partially leave the polyphenol oxidase in the raw tea leaves and partially fermented ( Tannin oxidation reaction) to produce a tea having both the characteristics of green tea and black tea. The fermentation of raw tea leaves and the extraction of fermented tea can be performed in a single step by the slurry fermentation method and the tea-derived method. It does not mention efficient water extraction of soluble solids other than tannins.
[0021]
Patent Literature 13 proposes increasing the extraction efficiency of tea leaf components from steam-heat-treated tea leaves with a decomposing enzyme such as cellulase, concentrating and freezing the obtained extract, and packaging the resultant in an oxygen-impermeable film. However, it does not refer to a slurry fermentation method in which fermentation of raw tea leaves and extraction of fermented tea can be performed in a single step.
[0022]
Patent Document 14 proposes that green tea, oolong tea, black tea, etc., produced by tea is crushed to destroy the tissue of tea leaves and water is added to form a slurry, thereby efficiently increasing the extraction efficiency of tea leaf components. It does not refer to a slurry fermentation method in which fermentation of raw tea leaves and extraction of fermented tea can be performed in a single step.
[0023]
In Patent Document 15, black tea leaves are enzymatically treated with tannases and cell wall lysing enzymes cellulase, hemicellulase, pectinase, dextranase, lysozyme, protease, lipase and mixtures thereof, and the yield of black tea from black tea leaves and A method for increasing the solubility of tea solids has been proposed, but in this document it is limited to black tea leaves, and the subject of enzyme treatment is black tea, which is a fermented tea that has already been fermented (tannin oxidation reaction). In addition, before extracting the tea liquor from the tea leaves with boiling water, a complicated process of wetting tannase and a cell wall lysing enzyme solution to the tea leaves to perform partial digestion and fermentation of the tea leaves. Slurry generation that can simultaneously perform the fermentation process and the extraction process from fermented tea such as black tea in a single process using raw tea leaves before withering The law is intended to clearly a difference.
[0024]
In Patent Document 16, raw or dried tea leaves are treated with plant tissue degrading enzymes such as pectinase and hemicellulase to extract flavor components, pigment components, nutrient components and functional components in the tea leaves in a high yield, and then dry finely powdered green tea However, since the object of the invention is green tea that does not undergo fermentation (tannin oxidation reaction), raw or dried raw tea leaves are heated and dried at high speed before the action of plant tissue degrading enzymes. It does not refer to a slurry fermentation method in which fermentation and fermented tea extraction can be performed in a single step.
[0025]
Patent Literature 17 proposes a fermented tea beverage obtained by adding an appropriate amount of a sweetener and an acidulant to a leachate leached from fermented tea obtained by fermenting (tannin oxidation reaction) second and / or third teas. However, it does not mention a slurry fermentation method in which fermentation of raw tea leaves and an extraction step of fermented tea can be performed in a single step, and efficient water extraction of soluble solids other than tannin derived from tea leaves.
[0026]
In Patent Document 18, a case is installed inside the housing in the fermentation step when tea leaves are made from raw tea leaves, and a case is further installed inside. The raw tea leaves are put in this case, and inside the housing. By supplying steam or hot water, it has been proposed to control the temperature and humidity inside the housing and promote the control of fermentation of raw tea leaves, but the fermentation of raw tea leaves and the extraction process of fermented tea are a single process. Does not mention the slurry fermentation method and the efficient water extraction of soluble solids other than tannin derived from tea leaves.
[0027]
Patent Document 19 proposes a method of treating a slurry of green tea (fresh tea leaves) with tannase and fermenting the slurry to obtain a tea extract having an excellent color tone rich in theaflavin. However, tannin derived from tea leaves is proposed. It does not mention efficient water extraction of other soluble solids.
[0028]
Patent Literature 20 proposes a method for producing black tea having an improved aroma by adding phenolic acid and an amino acid before fermenting leaf green tea (raw tea leaves) and fermenting the green tea leaves. It does not refer to a slurry fermentation method in which the fermented tea extraction step can be performed in a single step and an efficient water extraction of soluble solids other than tannin derived from tea leaves.
[0029]
In Patent Document 21, a green tea extract is mixed with a plant extract such as tea, fruits, vegetables, herbs and the like containing polyphenol oxidase (polyphenol oxidase), and mixed with a polyphenol oxidase in the plant extract without impairing the flavor of green tea. A method for producing a green tea extract containing theaflavins and a variety of plant flavors, in which catechins abundantly contained in green tea are oxidized to theaflavins by the action of an enzyme (polyphenol oxidase), has also been proposed. The target is green tea extract, green tea extract is used as a raw material, and other various plant flavors are added, so slurry fermentation that can perform the original fermentation of raw tea leaves and the extraction process of fermented tea in a single process No mention is made of the method or efficient water extraction of soluble solids other than tannins from tea leaves.
[0030]
The slurry fermentation method in which the fermentation of the raw tea leaves and the extraction process of the fermented tea can be performed in a single step has been conventionally known, but the fermentation (tannin oxidation reaction) is efficiently performed. Method for freezing and then thawing fresh tea leaves to destroy fresh tea leaf tissue to promote fermentation (tannin oxidation reaction), adding microbial polyphenol oxidase (polyphenol oxidase), or plant-derived polyphenol oxidase A method of adding (polyphenol oxidase) has been proposed. Further, a method of decomposing tannin, which is a source of turbidity, with tannase and a method of decomposing turbid components other than tannin with pectinase, amylase, etc. to prevent turbidity of fermented tea. A method has been proposed in which is applied to a slurry fermentation method.
[0031]
On the other hand, efficient water extraction of soluble solids other than tannin derived from tea leaves in the slurry fermentation method involves adding cellulase, hemicellulase, pectinase, protopectinase (plant tissue disintegrating enzyme), etc. to fresh tea leaves in the extraction step. Although a method for increasing the tea component has been proposed, there is no mention of a fermentation (tannin oxidation reaction) step performed simultaneously with the extraction step in the slurry fermentation method, and only the leaves of black tea after the fermentation step have tannase, cellulase, A solution of hemicellulase, pectinase, protopectinase (plant tissue disintegrating enzyme) and the like is added to wet the leaves of black tea to cause enzymatic degradation, hydrolyze tannins and destroy and decompose the tissues of tea leaves. It is said that efficient water extraction of soluble solids other than tannin derived from tea leaves by hot water extraction in the process of It is only complicated processes have been proposed. For other methods, green tea, oolong tea, black tea, etc., other than raw tea leaves are destroyed by the action of a tea leaf tissue-destructing enzyme, or a method of mechanically destroying the tea leaf tissue to increase the tea component. Is only proposed.
[0032]
That is, in a slurry fermentation method in which raw tea leaves, which are raw materials of tea leaves, are crushed and a fermentation process of raw tea leaves and an extraction process of fermented tea are performed in a single process, fermentation (tannin oxidation reaction) is performed and tea leaves are produced. There is no finding of an extraction method that enhances the umami component by causing efficient water extraction of soluble solids other than tannin derived from the tannin, and consequently reduces bitterness and enhances body and umami.
[0033]
In this manner, in a slurry fermentation method in which the fermentation of raw tea leaves and the extraction step of fermented tea are performed in a single step, the fermentation (tannin oxidation reaction) is performed, and the tea leaves are manufactured in a simpler method. In a situation where it is strongly desired to develop a fermented tea production method that enhances umami components by performing efficient water extraction of soluble solids other than tannins derived from it, resulting in less bitterness and enhanced body and umami there were.
[0034]
[Patent Document 1]
JP-B-39-746
[Patent Document 2]
JP-B-44-1932
[Patent Document 3]
JP-B-46-17958
[Patent Document 4]
JP-B-46-15679
[Patent Document 5]
Japanese Patent Publication No. 48-16636
[Patent Document 6]
JP-B-48-31919
[Patent Document 7]
Japanese Patent Publication No. 50-30717
[Patent Document 8]
JP-A-51-115999
[Patent Document 9]
JP-A-54-140797
[Patent Document 10]
JP-A-56-85244
[Patent Document 11]
JP-B-62-15175
[Patent Document 12]
JP-B-62-175138
[Patent Document 13]
JP-A-2-203743
[Patent Document 14]
JP-A-4-271750
[Patent Document 15]
Japanese Patent Publication No. 4-63662
[Patent Document 16]
JP-A-5-316952
[Patent Document 17]
Tokuho 6-95882
[Patent Document 18]
JP-A-7-227210
[Patent Document 19]
JP-A-11-225672
[Patent Document 20]
JP 2000-228951 A
[Patent Document 21]
JP-A-2002-95415
[0035]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and by performing fermentation (tannin oxidation reaction) of raw tea leaves and aqueous extraction of soluble solids other than tannin derived from tea leaves in a single step, Fermented tea leaf extract with less bitterness and richness and umami can be obtained efficiently, and the fermented tea leaf extract can be adjusted to any flavor or color by changing the fermentation (tannin oxidation reaction) treatment time It is a primary object of the present invention to provide a method for producing a fermented tea leaf extract that can be prepared.
[0036]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides, as described in claim 1, a method in which crushed raw tea leaves before wilt treatment and a solution of a tea leaf tissue-destructing enzyme are mixed and fermented (tannin oxidation reaction). And a method for producing a fermented tea leaf extract, wherein the tea leaf tissue destruction enzyme treatment and the extraction treatment are performed in a single step.
[0037]
The present invention performs the fermentation of raw tea leaves and the aqueous extraction of soluble solids other than tannin derived from tea leaves by throwing the thus-crushed raw tea leaves into a solution of a tea leaf tissue-destructing enzyme. be able to. Therefore, it is possible to obtain a fermented tea leaf extract that can produce a fermented tea beverage having less bitterness and richness and umami by a simple method. In addition, the present invention adjusts the resulting fermented tea leaf extract to an arbitrary flavor or color by performing fermentation (tannin oxidation reaction), treatment with a tea leaf tissue-destructing enzyme, and extraction treatment at any given temperature and time. It is possible.
[0038]
In the invention described in claim 1, as described in claim 2, it is preferable that the tea leaf tissue disrupting enzyme has at least one selected from the group consisting of cellulase, hemicellulase, and protopectinase. By using cellulase, hemicellulase, protopectinase and a mixed enzyme thereof, it is possible to efficiently extract water-soluble solids other than tannin derived from tea leaves with a small amount of tea leaves, less bitterness, and richness. Thus, a fermented tea leaf extract capable of producing a fermented tea beverage having good umami taste can be obtained.
[0039]
In the invention described in claim 1 or 2, as described in claim 3, it is preferable that the tea leaf tissue disrupting enzyme has hemicellulase. Among the above enzymes, hemicellulase is particularly high in water extraction efficiency of soluble solids other than tannin derived from tea leaves, and fermented tea beverages using the obtained fermented tea leaf extract have less bitter taste, richness and umami. Is good.
[0040]
In the invention described in any one of claims 1 to 3, as described in claim 4, the fresh tea leaves are fresh tea leaves immediately after plucking or refrigerated or frozen immediately after plucking. It is preferably a preserved raw tea leaf. By using such fresh tea leaves, it is easy to control the degree of fermentation (tannin oxidation reaction), and it is easy to obtain a fermented tea leaf extract that can produce a fermented tea beverage whose flavor or color is adjusted according to palatability. This is because
[0041]
In the invention described in any one of claims 1 to 4, as described in claim 5, the fermentation (tannin oxidation reaction), the tea leaf tissue destruction enzyme treatment, and the extraction treatment are performed. , 20 ° C to 60 ° C. When the temperature is lower than the above range, the reaction rate of the tea leaf tissue-destructing enzyme is slowed down, so that it may take time to extract. This is because, due to the deactivation, the effect of the tea leaf tissue-destructing enzyme is reduced, so that it may be difficult to obtain a predetermined flavor or color, which is not preferable.
[0042]
In the invention described in any one of claims 1 to 5, as described in claim 6, the fermentation (tannin oxidation reaction), the tea leaf tissue destruction enzyme treatment, and the extraction treatment are performed. It is preferable that the treatment be performed for one hour or more. If the length is shorter than the above range, the treatment of the tea leaf tissue-destructing enzyme may be insufficient.
[0043]
The present invention further provides, as described in claim 7, a Brix value of a fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract according to any one of claims 1 to 6. However, in the method for producing a fermented tea leaf extract, the Brix value of the fermented tea leaf extract obtained without using the tea leaf tissue-destroying enzyme is within a range of 1.3 to 1.5 times. To provide a fermented tea leaf extract.
[0044]
According to the present invention, since it is a fermented tea leaf extract obtained by the above-described method for producing a fermented tea leaf extract, the water extraction efficiency of soluble solids other than tannin derived from tea leaves is high, the amount of tea used is small, A fermented tea leaf extract that can produce a fermented tea beverage with less taste and good body and umami can be obtained.
[0045]
The present invention also uses a fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract according to any one of claims 1 to 6, as described in claim 8. The present invention provides a method for producing a fermented tea beverage.
[0046]
According to the present invention, since the fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract according to any one of claims 1 to 6 is used, the bitter taste is reduced. Thus, a fermented tea beverage having a good body and good taste can be obtained.
[0047]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention comprises a method for producing a fermented tea leaf extract, a tea leaf extract obtained by the production method, and a method for producing a fermented tea beverage using the same. In the present invention, the term “fermented tea beverage” includes fermented tea beverages having any degree of fermentation (tannin oxidation reaction). Hereinafter, these will be described.
[0048]
A. Production method of fermented tea leaf extract
First, the method for producing a fermented tea leaf extract of the present invention will be described in detail.
[0049]
1. raw materials
In the method for producing a fermented tea leaf extract of the present invention, raw tea leaves, tea tissue-destructing enzymes, additives, water and the like are prepared as raw materials.
[0050]
(1) Raw tea leaves
The fresh tea leaves in the present invention are not particularly limited as long as they are tea leaves before the withering treatment. However, in the present invention, in order to facilitate the adjustment of the degree of fermentation (tannin oxidation reaction), fresh tea leaves are preferably used by crushing fresh tea as much as possible.
[0051]
Therefore, it is preferable to use fresh tea leaves immediately after pruning or fresh tea leaves refrigerated or frozen immediately after plucking. In the case of refrigeration, those stored for 1 to 2 days are preferably used.
[0052]
Here, “immediately after plucking” in the present invention refers to a case within 24 hours after plucking, preferably within 6 hours after plucking. This is because if more time elapses after plucking, it becomes difficult to control fermentation (tannin oxidation reaction), which is not preferable.
[0053]
Since the present invention uses raw tea leaves before withering in this way, it is generally unnecessary to perform the withering treatment required for the production of fermented tea. Therefore, since there is no need for equipment for performing withering treatment, it is possible to obtain tea leaves at a low cost, and in a domestic tea leaf production area that does not have a withering treatment equipment that has conventionally produced green tea. It has the advantage that tea leaves can be used. Further, in the present invention, the use of fresh tea leaves before withering allows the degree of fermentation (tannin oxidation reaction) to be easily adjusted, and produces a fermented tea beverage whose flavor is adjusted according to palatability. It is easy to obtain a fermented tea leaf extract that can be used.
[0054]
The raw tea leaves used in the present invention are those obtained by removing leaves and stems of a tea plant (Camellia sinensis) and not subjected to heat inactivation treatment of polyphenol oxidase, which is an oxidase. The fresh tea leaves of the present invention can be used from any production area, and there is no particular limitation on the time of harvesting.Either a new tea leaf that is a sprout in early spring, a soft fresh young leaf that is somewhat fertile in early summer, or a fresh tea leaf with a mature hard tissue However, it is preferable to use fresh tea leaves or fresh young leaves from the viewpoint of the Brix value (hereinafter sometimes abbreviated as “Bx value”), flavor and color of the obtained fermented tea leaf extract.
[0055]
Here, the Bx value indicates the concentration of soluble solids including tannin in the fermented tea leaf extract, and the larger the Bx value, the more soluble solids other than tannin are extracted. , And are used as indices representing body and umami. The Bx value in the present invention uses a value measured by a refractometer.
[0056]
In the present invention, such raw tea leaves are used after crushing. As such a crushing method, a food cutter, a mixer, a hammer mill, an ultramizer and the like are appropriately used as necessary. The size of the crushed tea leaves is not particularly limited, but may be about 1 mm or less.
[0057]
(2) Tea leaf tissue destruction enzyme
The present invention provides a method in which fermentation (tannin oxidation reaction), treatment with a tea leaf tissue-destructing enzyme, and extraction treatment are performed in a single step by throwing such ground green tea leaves into an aqueous solution containing a tea leaf tissue-destroying enzyme. It is characterized by the following.
[0058]
The tea leaf tissue-destructing enzyme that can be used in the present invention is not particularly limited as long as it is an enzyme capable of breaking tea leaves so that the Bx value of the obtained tea leaf extract is high during the extraction treatment. In addition, not only a single enzyme but also a plurality of enzymes can be used in combination.
[0059]
In the present invention, it is particularly preferable that the tea leaf tissue is destroyed using at least one kind of tea leaf tissue disrupting enzyme selected from the group consisting of cellulase, hemicellulase and protopectinase, followed by extraction treatment. This is because the Bx value in the fermented tea leaf extract obtained by using these enzymes can be improved. In the present invention, these cellulases, hemicellulases and protopectinases can be used in combination.
[0060]
In the present invention, it is particularly preferable to use hemicellulase. This is because the use of hemicellulase can improve the taste, flavor, and the like of the finally obtained fermented tea.
[0061]
Hereinafter, each of these enzymes will be described in detail.
[0062]
a. Cellulase
The cellulase used in the present invention is an enzyme that hydrolyzes a β-1,4-glycosidic bond of cellulose to produce cellopose. In the present invention, any enzyme generally referred to as cellulase in the food industry can be used, and its origin is not particularly limited. Can also be used.
[0063]
In general, there are two types of cellulase derived from Trichoderma viride, which works well on natural cellulose such as cotton and paper, and cellulase derived from Aspergillus niger, which works well on chemically modified water-soluble cellulose (eg, CMC, etc.). It is manufactured and sold and used for disintegration and dissolution of plant tissues and the like. Specifically, Tri. cellulosine T2 of Asper. niger origin cellulosin AC40 or cellulosin AL (both sold by Hankyu Kyoei Bussan Co., Ltd.); virido-derived cellulase “Onozuka” 3S (sold by Yakult Yakuhin Kogyo Co., Ltd.); cellulase T “Amano” 4, Asp. Niger-derived cellulase A “Amano” 3 (both sold by Amano Enzyme Co., Ltd.) and the like can be used.
[0064]
In the present invention, such a cellulase is preferably used in the range of 0.03% to 0.20% by weight, particularly 0.08% to 0.15% by weight. When the amount added is less than the above range, the effect of improving the efficiency of the enzyme for treating tea leaf tissue destruction cannot be exhibited. This is because it is not possible and disadvantageous in terms of cost.
[0065]
b. Hemicellulase
Hemicellulase used in the present invention is an enzyme that performs a reaction to hydrolyze glycosidic bonds of hemicellulose. In the present invention, any enzyme generally referred to as hemicellulase in the food industry can be used, and its origin is not particularly limited. Even those can be used.
[0066]
Generally, Tri. virions and Asp. Niger-derived products are manufactured and sold, and are used for disintegration of fruits and mushrooms, softening of cereal tissues, and improvement of filterability of saccharified cereal juice.
[0067]
Specifically, Tri. cellulosine TP25 of Asper. niger origin cellulosin HC (both sold by Hankyu Kyoei Bussan Co., Ltd.), and Asp. niger origin cellulase Y-NC (sold by Yakult Yakuhin Kogyo Co., Ltd.), Asp. Niger-derived hemicellulase "Amano" 90 (available from Amano Enzyme Co., Ltd.) can be used.
[0068]
In the present invention, it is preferable to use such a hemicellulase in the range of 0.03% to 0.20% by weight, particularly 0.08% to 0.15% by weight. If the addition amount is less than the above range, the effect of improving the enzymatic decomposition extraction efficiency cannot be exerted. This is disadvantageous.
[0069]
c. Protopectinase
The protopectinase used in the present invention is an enzyme that acts on protopectin to produce a soluble pectin (soluble pectic acid), and is also referred to as a plant tissue disintegrating enzyme or a macerating enzyme. In the present invention, it is possible to use any enzyme generally referred to as a protopectinase, a plant tissue-disintegrating enzyme, or a macerating enzyme in the food industry, and its origin is not particularly limited, and Both purified and unpurified products can be used.
[0070]
Generally, those derived from the genus Rhizopus are sold, and have a function of acting on intercellular substances (mainly insoluble protopectin) between plant tissues to convert plant tissues into single cells. Specifically, cellulosin ME derived from the genus Rhizopus (available from Hankyu Kyoei Bussan Co., Ltd.), maceroteam A also derived from the genus Rhizopus (available from Yakult Pharmaceutical Co., Ltd.), and the like can be used.
[0071]
In the present invention, such a protopectinase is preferably used in a range of 0.03% to 0.20% by weight, particularly 0.08% to 0.15% by weight.
If the addition amount is less than the above range, the effect of improving the enzymatic decomposition extraction efficiency cannot be exerted. This is disadvantageous.
[0072]
(3) Additive
In the method for producing a fermented tea leaf extract of the present invention, an additive may be added in addition to the above-mentioned fresh tea leaves and the tea leaf tissue-destructing enzyme. Specific examples include taste modifying agents such as tannase, amylase, and protease, ascorbic acid or a salt thereof, polyvinyl polypyrrolidone, a pH adjuster, a flavor, and a coloring agent.
[0073]
(4) Water
In the present invention, the water used in performing the enzymatic decomposition extraction treatment is not particularly limited, but it is preferable to use deionized water or distilled water. As described above, deionized water or distilled water is preferable because, when calcium ions and iron ions are dissolved in water, the deionized water or distilled water forms bonds with tannin in the tea leaf extract, resulting in insoluble matter or color. This is to prevent the occurrence of a change.
[0074]
(5) Weight ratio
In the present invention, the weight ratio of the raw materials in performing the fermentation (tannin oxidation reaction), the treatment of the tea leaf tissue-destructing enzyme, and the extraction treatment is significantly different depending on the type of raw tea leaves used, required palatability, and the like. It is not limited. However, in general, ground tea leaves are added in the range of 5.0% by weight to 30% by weight, and fermentation, tea leaf tissue destruction enzyme treatment, and extraction treatment are performed. Moreover, it is preferable to use the total addition amount of the tea-leaving enzyme in the range of 0.03% by weight to 0.20% by weight, particularly 0.08% by weight to 0.15% by weight.
[0075]
2. Fermentation (tannin oxidation reaction), tea leaf tissue destruction enzyme treatment, and extraction treatment conditions
In the present invention, the crushed raw tea leaves are thrown into a previously prepared solution of a tea leaf tissue-destructing enzyme, and fermentation (tannin oxidation reaction), tea leaf tissue destruction treatment and extraction treatment are performed in a single step. is there.
[0076]
In such fermentation (tannin oxidation reaction), tea leaf tissue destruction enzyme treatment, and extraction treatment, the Bx value and the degree of fermentation (tannin oxidation reaction) in the obtained fermented tea leaf extract are changed depending on conditions such as temperature and time. It fluctuates greatly. Hereinafter, these processing conditions will be described.
[0077]
(1) Temperature
In the present invention, the fermentation (tannin oxidation reaction) of the crushed raw tea leaves and the treatment of the tea leaf tissue-destructing enzyme are preferably performed at a relatively low temperature. Specifically, it is preferable to carry out in the range of 20 ° C to 60 ° C, especially in the range of 35 ° C to 55 ° C.
[0078]
When performed at a temperature lower than the above range, the reaction rate of the tea leaf tissue-destructing enzyme is slowed down, so that in order to obtain a fermented tea leaf extract having a predetermined Bx value, a lot of time is required and it is not efficient, and it is not sufficient. This is because the Bx value of the obtained fermented tea leaf extract may not be sufficient since the tea tissue-destructing enzyme may not work. On the other hand, when performed at a temperature higher than the above range, the heat inactivation of the tea leaf tissue-destroying enzyme reduces the effect of the tea leaf tissue-destroying enzyme, and also inactivates the oxidase present in the raw tea leaves, thereby providing a predetermined activity. It is not preferable because flavor or color may not be obtained.
[0079]
(2) Time
The treatment time in the fermentation (tannin oxidation reaction), the tea leaf tissue destruction enzyme treatment, and the extraction treatment is preferably 1 hour or more, and particularly preferably in the range of 1 hour to 10 hours.
If the treatment is carried out for a treatment time shorter than the above range, the treatment of the tea leaf tissue-destructing enzyme is not sufficient, and it is not preferable because the Bx value required in the tea leaf extract cannot be obtained. The Bx value in the present invention saturates in a processing time of about one hour, and the amount of increase in the Bx value is small even if the processing time is further increased. Therefore, after one hour has elapsed, the treatment time may be appropriately determined based on the change in the flavor and color of the fermented tea leaf extract according to the degree of fermentation (tannin oxidation reaction) required. Specifically, if the treatment time is reduced, it is possible to obtain a fermented tea having a bluish green leaf odor peculiar to green tea and a light reddish brown color peculiar to fermented tea. The odor disappears, and fermented tea having an aged flavor unique to black tea can be obtained. In any case, the resulting fermented tea has a less bitter taste and a strong and umami taste.
[0080]
(3) When to crush raw tea leaves
In the present invention, fresh tea leaves are used by crushing, but at the time of crushing of fresh tea leaves, the above tea leaf tissue-destroying enzyme is mixed and added to water to prepare a solution of tea leaf tissue-destroying enzyme, It is preferable that the preparation is performed after the temperature of the preparation is set to a predetermined temperature. Fermentation (tannin oxidation reaction) of raw tea leaves starts at the stage of crushing treatment, but by doing so, the degree of fermentation (tannin oxidation reaction) according to taste can be easily adjusted.
[0081]
(4) Other
In the present invention, since fermentation (tannin oxidation reaction) is oxidative fermentation, when fermentation (tannin oxidation reaction) and tea leaf tissue destruction enzyme treatment extraction are performed in a short time, entrainment and dissolution of oxygen in the air are performed. It is preferable to stir the treatment liquid vigorously or to blow air or oxygen into the treatment liquid.
[0082]
B. Fermented tea leaf extract
After performing the above-mentioned fermentation (tannin oxidation reaction), tea leaf tissue destruction enzyme treatment, and extraction treatment, the fermented tea leaf extract is passed through an enzyme inactivation treatment step by heating and a solid-liquid separation step such as centrifugation or filtration. Obtainable.
[0083]
In the present invention, since the drainage from tea leaves in the solid-liquid separation step is good, the recovered amount of the fermented tea leaf extract is extremely large as compared with the case where the tea leaf tissue disrupting enzyme is not used, and the amount of industrial waste is small. The advantage is obtained.
[0084]
The fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract of the present invention as described above has a high ratio of soluble solids other than tannin derived from tea leaves, so that the fermented tea has a less bitter taste and a strong richness and umami. Beverages can be manufactured.
[0085]
The Bx value in the fermented tea leaf extract obtained by such a method for producing a fermented tea leaf extract of the present invention is based on the Bx value of the fermented tea leaf extract obtained without using a tea leaf tissue disrupting enzyme in the method described above. It shows 1.3 times to 1.5 times. Therefore, by using this fermented tea leaf extract, it is possible to obtain a fermented tea beverage having less bitterness and richness and umami.
[0086]
Further, the fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract of the present invention has a flavor and color adjusted according to palatability. A fermented tea beverage or a fermented tea beverage having an aging flavor such as black tea can be arbitrarily manufactured.
[0087]
C. Production method of fermented tea beverage
The method for producing a fermented tea beverage of the present invention is characterized by using the fermented tea leaf extract obtained by the above-described method for producing a fermented tea leaf extract.
[0088]
That is, the tea leaf extract obtained by the method for producing a tea leaf extract described above is diluted, for example, in an amount such that the Bx value in the fermented tea beverage has a predetermined concentration, and further, an additive or the like is added and stirred. Can be manufactured.
[0089]
1. Adjustment of Bx value
In the fermented tea beverage of the present invention, the Bx value in the fermented tea beverage is not particularly limited, but is preferably adjusted to be in the range of 0.15 to 0.35, particularly 0.20 to 0.30. . By setting the Bx value in this range, it is possible to obtain a fermented tea beverage having less bitterness and good richness and umami. At this time, the same diluent as water used in the above-described method for producing a fermented tea leaf extract can be used.
[0090]
2. Additive
Examples of the additives that can be used in the present invention include ascorbic acid or a salt thereof as a browning inhibitor and a pH adjuster, sodium bicarbonate as a pH adjuster, and flavors. Hereinafter, each will be described.
[0091]
a. Ascorbic acid or its salt
In the present invention, by adding ascorbic acid or a salt thereof during production of the fermented tea beverage, it is possible to prevent browning over time during storage of the fermented tea beverage.
[0092]
The addition amount of ascorbic acid or a salt thereof in the present invention is preferably in the range of 200 ppm to 700 ppm, particularly preferably in the range of 400 ppm to 650 ppm. When the addition amount is less than the above range, the browning inhibitory effect is not sufficient, and it is not preferable because it may not be possible to cope with browning over time during storage. It is not preferable because there is a possibility of causing modulation of flavor such as slimming.
[0093]
In the present invention, only ascorbic acid may be added, only a salt of ascorbic acid may be added, or ascorbic acid and a salt of ascorbic acid may be added together. However, from the viewpoint of preventing browning, it can be said that the use of ascorbic acid sodium salt is a particularly preferred embodiment.
[0094]
b. pH adjuster
In the present invention, a pH adjuster is used to optimize the pH value of the fermented tea beverage. Examples of the pH adjuster used in the present invention include the above-described ascorbic acid or a salt thereof, and further include sodium hydrogen carbonate.
[0095]
The amount of these pH adjusters to be added is appropriately determined so that the resulting fermented tea beverage has the desired pH. However, ascorbic acid or a salt thereof is required to prevent browning as described above. Since the fixed amount is added, the amount of sodium hydrogen carbonate to be added is determined so that the fermented tea beverage to which ascorbic acid or a salt thereof is added has a predetermined pH.
[0096]
c. Other additives
In the present invention, besides, for flavoring, coloring, antioxidant or antibacterial purposes, flavoring agents such as tea flavor, coloring agents such as chlorophyll, antioxidants such as rutin, and antibacterial agents such as sucrose fatty acid ester, respectively. An emulsifier or the like may be appropriately added.
[0097]
3. Fermented tea beverage
The fermented tea beverage obtained in the present invention has a flavor ranging from a semi-fermented tea having a greenish smell peculiar to green tea to a fermented tea having a matured flavor peculiar to black tea by appropriately selecting a fermented tea leaf extract according to palatability. And color can be adjusted arbitrarily. In addition, the fermented tea beverage of the present invention uses a fermented tea leaf extract having a high Bx value, so that it has less bitterness and good body and umami.
[0098]
Note that the present invention is not limited to the above embodiment. The above embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and has the same effect. Within the technical scope of
[0099]
【Example】
Hereinafter, the present invention will be further described with reference to Examples.
[0100]
[Preparation of fermented tea leaf extract using hemicellulase]
An issued tea leaf extract was prepared by the method described below, and the fermented tea leaf extract of each example was quantitatively evaluated for the Bx value contained in the extract with a refractometer, and the flavor was evaluated by a specialized panelist.
[0101]
(Example 1)
21.0 parts by weight of fresh tea leaves which have not been withered within 6 hours after plucking are crushed and treated with hemicellulase (sold by Amano Enzyme Co., Ltd., trade name Hemicellulase "Amano" 90, from Asp.niger) 0.1 The fermented tea leaves accompanied by fermentation (tannin oxidation reaction) and destruction of the tea leaf tissue by hemicellulase by adding 1 part by weight to 78.9 parts by weight of deionized water, adding to a solution obtained by mixing and dissolving, and stirring at 45 ° C. for 1 hour. An extraction process was performed.
[0102]
Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 78 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 75 parts by weight of a clear fermented tea leaf extract.
[0103]
The Bx value of the obtained fermented tea leaf extract was 3.0. The light blue color was slightly reddish-brown, and the flavor was green tea-flavored with a green leafy odor. However, it was less bitter and had a rich and umami taste.
[0104]
(Example 2)
21.0 parts by weight of fresh tea leaves which have not been withered within 6 hours after plucking are crushed and treated with hemicellulase (sold by Amano Enzyme Co., Ltd., trade name Hemicellulase "Amano" 90, from Asp.niger) 0.1 The fermented tea leaves accompanied by fermentation (tannin oxidation reaction) and destruction of the tea leaf tissue by hemicellulase by adding 3 parts by weight to 78.9 parts by weight of deionized water, adding to a mixed solution obtained by mixing and dissolving, and stirring at 45 ° C. for 3 hours. An extraction process was performed.
[0105]
Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 78 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 75 parts by weight of a clear fermented tea leaf extract.
[0106]
The Bx value of the obtained fermented tea leaf extract was 3.1. In addition, the light blue color was reddish brown, and the flavor was slightly black tea flavor. However, it was less bitter and had richness and umami.
[0107]
(Example 3)
21.0 parts by weight of fresh tea leaves which have not been withered within 6 hours after plucking are crushed and treated with hemicellulase (sold by Amano Enzyme Co., Ltd., trade name Hemicellulase "Amano" 90, from Asp.niger) 0.1 The fermented tea leaves are added to 78.9 parts by weight of deionized water, added to a mixed solution obtained by mixing and dissolving, stirred at 45 ° C. for 6 hours, and fermented (tannin oxidation reaction) and destruction of the tea leaf tissue by hemicellulase. An extraction process was performed.
[0108]
Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 80 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 78 parts by weight of a clear fermented tea leaf extract.
[0109]
The Bx value of the obtained fermented tea leaf extract was 3.2. In addition, the light blue color was black-red-brown and the flavor was also black tea flavor. However, it was less bitter and had a rich and umami taste.
[0110]
(Example 4)
21.0 parts by weight of fresh tea leaves which have not been withered within 6 hours after plucking are crushed, and 0.1% by weight of cellulase (available from Amano Enzyme Co., Ltd., trade name Cellulase T "Amano" 4, from Tricho.viride). The fermentation (tannin oxidation reaction) and fermented tea leaf extraction treatment accompanied by cellulase destruction of the tea leaf tissue by adding the mixture to 78.9 parts by weight of deionized water, adding the resulting mixture to a dissolved solution, and stirring at 45 ° C. for 1 hour. Was done. Subsequently, after completion of the fermented tea leaf extraction treatment, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 77 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 73 parts by weight of a clear fermented tea leaf extract.
[0111]
The Bx value of the obtained fermented tea leaf extract was 2.8. Further, the light blue color was slightly reddish brown, and the flavor was green tea flavor with a green leafy odor, and although it was slightly bitter, it was rich and umami.
[0112]
(Example 5)
21.0 parts by weight of fresh tea leaves that have not been withered within 6 hours after plucking are crushed, and 0.1 parts by weight of protopectinase (available from Hankyu Kyoei Bussan Co., Ltd., trade name Cellulosin ME, derived from Rhi.sp) is added. The fermentation (tannin oxidation reaction) and fermentation tea leaf extraction treatment accompanied by destruction of the tea leaf tissue by protopectinase were performed by adding the mixture to 78.9 parts by weight of deionized water, mixing and dissolving the mixture, and stirring at 45 ° C. for 1 hour. went. Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 76 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 73 parts by weight of a clear fermented tea leaf extract.
[0113]
The Bx value of the obtained fermented tea leaf extract was 2.7. Further, the light blue color was slightly reddish brown, and the flavor was green tea flavor with a green leafy odor, and although it was slightly bitter, it was rich and umami.
[0114]
(Example 6)
21.0 parts by weight of fresh tea leaves which have not been withered within 6 hours after plucking are crushed, and hemicellulase (sold by Amano Enzyme Co., Ltd., trade name hemicellulase "Amano" 90, derived from Asp.niger) 0.04 Parts by weight, 0.03 parts by weight of cellulase (sold by Amano Enzyme Co., Ltd., trade name: Cellulase T "Amano" 4, from Tricho.viride) and protopectinase (sold by Hankyu Kyoei Bussan Co., Ltd., trade names: cellulosin ME, derived from Rhi.sp) ) 0.03 parts by weight was added to 78.9 parts by weight of deionized water, and the mixture was added to the mixed solution, and the mixture was stirred at 45 ° C for 1 hour to carry out fermentation (tannin oxidation reaction) and the above three enzyme groups Tea leaf extraction treatment accompanied by tea leaf tissue destruction was performed. Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 76 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 73 parts by weight of a clear fermented tea leaf extract.
[0115]
The Bx value of the obtained fermented tea leaf extract was 2.8. Further, the light blue color was slightly reddish brown, and the flavor was green tea flavor with a green leafy odor, and although it was slightly bitter, it was rich and umami.
[0116]
(Comparative Example 1)
Fermentation (tannin oxidation) is performed by crushing 21.0 parts by weight of unteared fresh tea leaves within 6 hours after plucking, adding the resulting mixture to 79.0 parts by weight of deionized water, and stirring at 45 ° C. for 1 hour. Reaction) and fermented tea leaf extraction treatment.
[0117]
Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 51 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 48 parts by weight of a clear fermented tea leaf extract.
[0118]
The Bx value of the obtained fermented tea leaf extract was 2.3. The light blue color was slightly reddish-brown, and the flavor was green tea-flavored with a green leafy odor. However, it had a bitter taste and was less rich and umami.
[0119]
(Comparative Example 2)
Fermentation (tannin oxidation) is performed by crushing 21.0 parts by weight of unteared raw tea leaves within 6 hours after plucking, adding the resulting mixture to 79.0 parts by weight of deionized water, and stirring at 45 ° C. for 3 hours. Reaction) and fermented tea leaf extraction treatment.
[0120]
Subsequently, after completion of the fermented tea leaf extraction process, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 51 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 48 parts by weight of a clear fermented tea leaf extract.
[0121]
The Bx value of the obtained fermented tea leaf extract was 2.3. The light blue color was reddish-brown, and the flavor was slightly black. However, the flavor was bitter and had little richness and umami.
[0122]
(Comparative Example 3)
Fermentation (tannin oxidation) was performed by crushing 21.0 parts by weight of fresh tea leaves which had not been withered within 6 hours after plucking, adding the resulting mixture to 79.0 parts by weight of deionized water, and stirring at 45 ° C. for 6 hours. Reaction) and fermented tea leaf extraction treatment.
[0123]
Subsequently, after completion of the fermented tea leaf extraction treatment, the tea leaves were removed by a centrifugal separation operation through an enzyme inactivation treatment by heating at 80 ° C. for 10 minutes, and 53 parts by weight of the centrifuged extract was obtained. The centrifuged extract was further filtered through a 3 μm filter to obtain 50 parts by weight of a clear fermented tea leaf extract.
[0124]
The Bx value of the obtained fermented tea leaf extract was 2.4. In addition, the light blue color was black-red-brown, and the flavor was also black tea flavor.
[0125]
In Table 1, 10 parts by weight of each of the fermented tea leaf extracts obtained in Examples 1, 2, 3, 4, 5, and 6, and Comparative Examples 1, 2, and 3 was further used, and sodium ascorbate was further added. The results of sensory evaluation are shown for the flavor comparison of fermented tea beverages containing 350 ppm, adjusted to pH 6.5 using sodium hydrogen carbonate, and then subjected to retort sterilization using 100 parts by weight of the remaining deionized water.
[0126]
As is clear from the results in Table 1, the extraction efficiency of the soluble solids derived from tea leaves was higher when the enzyme treatment was performed, and the bitter taste was less, and the body and umami were higher than when the enzyme treatment was not performed.
[0127]
[Table 1]

[0128]
[Study on suitable slurry fermentation temperature]
Next, in the same manner as in Examples 1, 2, and 3, appropriate treatment in the case of using 0.1 parts by weight of hemicellulase (sold by Amano Enzyme Co., Ltd., trade name: hemicellulase "Amano" 90, derived from Asp.niger). Table 2 shows the results of the examination of the temperature.
[0129]
The enzyme treatment time was 3 hours for each.
[0130]
[Table 2]

[0131]
As is clear from the results in Table 2, below 20 ° C, the extraction efficiency of soluble solids derived from tea leaves is small, and above 60 ° C, the extraction efficiency of soluble solids derived from tea leaves is also small. The temperature at which fermented tea leaves are extracted with hemicellulase (sold by Amano Enzyme Co., Ltd., trade name Hemicellulase "Amano" 90, derived from Asp. Niger) and which involves destruction of tea leaf tissue is preferably 20 to 60C, and more preferably 35 to 55C. It has been found.
[0132]
【The invention's effect】
According to the present invention, by changing the fermentation (tannin oxidation reaction) treatment time of crushed fresh tea leaves according to palatability, a fermented tea beverage having any flavor and color can be obtained. Further, according to the present invention, it is possible to efficiently obtain a fermented tea beverage having less bitterness and good richness and umami.

Claims (8)

It is characterized by mixing the crushed raw tea leaves before wilt treatment with a solution of tea leaf tissue-destructing enzyme, and performing fermentation (tannin oxidation reaction), tea leaf tissue-destructing enzyme treatment, and extraction treatment in a single step. A method for producing a fermented tea leaf extract. The method for producing a fermented tea leaf extract according to claim 1, wherein the tea leaf tissue-destroying enzyme includes at least one selected from the group consisting of cellulase, hemicellulase, and protopectinase. The method for producing a fermented tea leaf extract according to claim 1 or 2, wherein the tea leaf tissue-destroying enzyme includes hemicellulase. The fermented tea leaf extraction according to any one of claims 1 to 3, wherein the fresh tea leaf is fresh tea leaf immediately after plucking, or fresh tea leaf refrigerated or frozen immediately after plucking. Liquid production method. The method according to any one of claims 1 to 4, wherein the fermentation (tannin oxidation reaction), the tea leaf tissue destruction enzyme treatment, and the extraction treatment are performed at a temperature in a range of 20C to 60C. Item 13. The method for producing a fermented tea leaf extract according to item 9. The fermentation according to any one of claims 1 to 5, wherein the fermentation (tannin oxidation reaction), the tea leaf tissue destruction enzyme treatment, and the extraction treatment are performed for one hour or more. A method for producing a tea leaf extract. The Brix value of the fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract according to any one of claims 1 to 6, wherein the Brix value of the fermented tea leaf extract is reduced in the method for producing a fermented tea leaf extract. A fermented tea leaf extract characterized by being in a range of 1.3 to 1.5 times the Brix value of a fermented tea leaf extract obtained without using an enzyme. A method for producing a fermented tea beverage, comprising using the fermented tea leaf extract obtained by the method for producing a fermented tea leaf extract according to any one of claims 1 to 6.