JP4360975B2 - Method for producing unfermented tea with high greenness and unfermented tea with high greenness - Google Patents

Description

The present invention relates to a novel non-fermented tea that can maintain a green color that has never been beautiful in non-fermented tea provided as a beverage in a container such as a PET bottle, and a method for producing the non-fermented tea. Is.

  Beverages that are drunk on a daily basis are mainly made from leaves of the same variety belonging to the camellia family. There is an enzyme in this tea leaf, and if you leave the leaves picked up, the enzyme will gradually turn brown by the action of this enzyme, so the enzyme's action is stopped by heat treatment etc., and the tea leaves are unfermented It is green tea that is extracted and processed as a green beverage. In recent years, in addition to semi-fermented tea such as oolong tea and black tea that have been consumed as bottled beverages in the past, this green tea or green tea is blended with other leaf teas, functional ingredients and nutritional ingredients, and cans The market for green tea drinks used as beverages and bottled drinks has expanded rapidly. However, bottled beverages and the like must be stored as an extract in a container for a long period of time, unlike a normal tea mode in which tea is extracted from tea leaves with hot water and drunk in the warm environment. In addition to maintaining the flavor in the meantime, there was a difficult problem of maintaining the green color, which has the most influence on the texture of green tea.

  However, there have been no examples of practically overcoming the problem until now, and there is no green tea beverage marketed as a bottle beverage or the like that maintains a beautiful green color just extracted from the tea leaves. It is appropriate to say that most of them supplement the impression with the color of the container and the packaging design.

Although it is such a present condition, as a method of stabilizing the green color of green tea, the tea leaf extract is heat-treated in a copper container, or the heated extract is passed through a column filled with copper particles in the extract. A method for stabilizing the green color of a green tea extract using copper chlorophyll as a copper chlorophyll has been reported (Patent Document 1). There is no other literature on the method of maintaining the green color of green tea produced in a packaging form such as a bottle container in relation to the invention of the present application, but for pickles such as bracken and cucumber and sugar beet, these plants The green color of the plant body is fixed or restored by heat immersion treatment with a treatment solution containing zinc ions and iron ions, or with a treatment solution containing metal-containing yeast such as zinc yeast, and then the green color is maintained. Have been reported (Patent Document 2, Patent Document 3).

Although there are reports as described above, as described above, green tea beverages such as bottle beverages that maintain a beautiful green color just after extraction from tea leaves after commercialization are not commercially available. As tea products that maintain a green color, there are powdered products such as powdered green tea that is made by pulverizing tea leaves as raw materials (for example, Patent Document 4), but this uses tea leaves themselves. It is not a product of the extract. On the other hand, for example, a tea leaf extract obtained by a method of performing extraction operation at a low temperature using a biaxial extruder or the like (Patent Document 5) shows a more beautiful green color than conventional commercial green tea beverages, and is also an amino acid related to umami Is extracted more than in the case of hot water extraction, an extract having a better flavor than the conventional hot water extract is obtained, which should be called a novel tea beverage. However, when the storage temperature of the extract in this patent document is slightly increased, it is clear that green fading rapidly proceeds, and in order to actually provide this extract as a product in a container such as a PET bottle, the temperature is higher. It was indispensable to solve the new technical problem of developing an effective green color maintenance method that maintains this high level of green beauty and yet does not affect the umami taste of this extract, which is rich in umami components.

Japanese Patent Laid-Open No. 7-112 Japanese Patent No. 2872971 JP 2004-67546 A JP-A-10-229838 JP 2004-41237 A

When the low temperature extraction method of Patent Document 5 is used for tea leaves, the present inventors can obtain an unprecedented extract that has a very high greenness and is rich in umami components in terms of flavor. We examined green maintenance methods that can effectively maintain the excellent characteristics of beautiful green color and rich umami even after commercialization that has been exposed to various storage conditions. We conducted an intensive study to provide good new plastic bottles and canned green tea drinks. In particular, there is a big difference between the greenness of the green tea beverage currently on the market and the low temperature extract (before heating) of the tea leaf produced by Patent Document 5, so the beautiful green color of this conventional low temperature extract is heated several times. Maintaining even products that have undergone a process and storage period has become the biggest issue.

Table 1 shows the results of measuring the Brix value (hereinafter referred to as Brix) of green tea beverages contained in main PET bottles currently on the market and the greenness as a value with a color difference meter. Originally, the a value as greenness is expressed as a minus a value, but there are no commercial products that have a minus a value, all showing a positive a value that is an index of redness, and from that value It became clear that green tea beverages in plastic bottles that are currently on the market are being offered to the market as reddish, wild-colored beverages rather than green tea. On the other hand, the previous low-temperature extract (unheated product) showed a value of minus 9 in Brix similar to the commercial product. For this reason, the first object of the present invention is to maintain the beautiful green color indicated by this low-temperature extract in the product as much as possible and provide it to the market as an unprecedented new green tea. The purpose of the present invention was to provide a new green tea drink having an a value about 1 lower than that of a commercially available product even after the test. In addition, the low temperature extract of Patent Document 5 has an umami component such as glutamic acid as compared with a conventional hot water extract, while it has a less bitter component such as tannin, and thus has an excellent flavor similar to gyokuro. ing. Therefore, it became a second problem to avoid sacrificing this good flavor by solving the first problem.

Usually, as a measure for preventing browning of a green tea beverage, an antioxidant such as ascorbic acid is added to prevent the oxidation reaction, or the air in the head space of the container is replaced with nitrogen. The present inventors also examined these methods and could not obtain the expected effect. On the other hand, the inventors of the present invention examined a different object from the object of the present invention, and stabilized chlorophyll of metal ions, particularly zinc ions and copper ions, for the purpose of enhancing and maintaining the green color of green tea, which is a ground product of tea leaves. Focusing on the effect, and examining zinc gluconate, it was found that zinc gluconate did not show the expected effect for green tea green enhancement and maintenance. However, since the low-temperature extract of Patent Document 5, which is the subject of the present invention, is not a pulverized product of tea leaves such as matcha tea, it contains zinc ions, copper ions, gluconates, sulfates, and metals. When added in the form of yeast or the like, unlike the case of Matcha, the green color of the extract is effectively maintained, and even after several high-temperature heat treatment steps, the green color of the extract is almost faded during those steps. I found it not. In addition, the effect is confirmed that the beautiful green color is maintained even after filling in the bottle container and stored at 30 ° C for 30 days, and there is no effect on the taste of tea by the additive. Has been successfully provided as a green tea beverage in a container such as a plastic bottle, and the present invention has been completed.

That is, the present invention is a method in which tea leaves are pulverized and extracted with a low-temperature solvent of 50 ° C. or lower in a biaxial extruder or colloid mill to separate an extract koji and an extract, and then the extract is mixed with zinc yeast, copper yeast, glucone. A green non-fermented product obtained by adding at least one green stabilizer selected from the group consisting of zinc acid, copper gluconate, zinc sulfate and copper sulfate to a metal concentration of 3 ppm to 100 ppm and then heat-treating it. The present invention relates to a method for producing tea.
Furthermore, this invention relates to the manufacturing method of the said green unfermented tea whose green stabilizer is selected from the group which consists of zinc yeast, zinc gluconate, and zinc sulfate.
Further, the present invention is manufactured by the above manufacturing method, and at least after the heat treatment, the value of the color difference a of the color tone in the Lab color difference meter is from 2.5 to minus 11 when the value of Brix is 0.1 or more and less than 0.4. It relates to a certain green unfermented tea.
Further, the present invention is manufactured by the above manufacturing method, and at least after heat treatment, the value of the color difference a of the color tone in the Lab color difference meter is from 3.0 to minus 10 when the value of Brix is 0.4 or more and less than 0.6. It relates to a certain green non-fermented tea.
In the present invention, the color difference a of the color tone in the Lab color difference meter after the heat treatment is from 2.5 to minus 11 when Brix is 0.1 or more and less than 0.4, and Brix is 0.4 or more and 0.00. It is 3.0 to minus 10 when less than 6, 5.0 to minus 6 when Brix is 0.6 or more and less than 1.0, and 6.0 when Brix is 1.0 or more and less than 2.0. It is related with the said green non-fermented tea which is minus 5.
Further, in the present invention, the value of the color difference a of the color tone in the Lab color difference meter after filling in the product container at 30 ° C. for 30 days is from 2.5 to minus 11 when the Brix is 0.1 or more and less than 0.4. When Brix is 0.4 or more and less than 0.6, 3.0 to minus 10; when Brix is 0.6 or more and less than 1.0, 5.0 to minus 6; It is related with said green non-fermented tea which is 6.0 to minus 5 when less than 0.
The present invention also relates to the green unfermented tea, wherein the product container is a plastic bottle, can, paper pack, cup, bottle, gable or cheer pack.

  The non-fermented tea with high greenness of the present invention can be obtained, for example, when the low-temperature extract shown in Patent Document 5 is used as an object, but even with tea leaf extracts obtained by other methods, good greenness is obtained. If it is a tea leaf extract which shows, non-fermented tea maintained in a state with no high greenness can be obtained by applying metal ions such as zinc ions and copper ions to the extract.

It is considered that the green color of the product of the present invention is stabilized by allowing zinc ions, copper ions and the like to act on the tea leaf extract and replacing the metal in the extract (perhaps the metal in chlorophyll). At this time, good results were not obtained with green tea, which is a crushed product of tea leaves.Therefore, the metal replacement is insufficient at the stage where the cell walls of the tea leaves remain, and the chlorophyll is extracted extracellularly after extraction. It is considered necessary to be exposed to On the other hand, Patent Documents 2 and 3 show that when a metal ion is allowed to act on a plant body itself, that is, even when a cell wall remains, there is a green restoration and maintenance effect. In the case of non-fermented tea, in order to inactivate the oxidase in the tea leaves, a heating operation is performed to steam the tea leaves (Japanese tea) or kettle roast (Chinese tea). It is considered that this heating operation changes the state of the cell wall and affects the replacement efficiency of metal ions.

As a method of allowing metal ions to act on the extract, when the Brix of the extract is about 0.3 in the form of gluconate, sulfate, metal-containing yeast, etc., the metal concentration is about 3 ppm to 100 ppm, preferably about 10 ppm to 60 ppm. More preferably, after adding each additive to the extract at about 15 ppm to 40 ppm, heat treatment is performed at 90 ° C. for about 10 minutes, for example, both for metal replacement and heat sterilization. If the heating temperature is high, the treatment time is shortened, and for example, sterilization and replacement can be performed simultaneously at 140 ° C. for 3 seconds using a plate heat exchanger.

The addition concentration of metal ions is determined in consideration of the green stabilization effect, the type of additive, the concentration of the extract (Brix), etc., but when metal ions are viewed as nutritional components, other criteria are taken into consideration. The addition concentration can also be determined. Other criteria include, for example, the daily concentration of zinc, copper, etc. (about 9 to 10 mg, reference; sixth revised Japanese nutritional requirement) to determine the concentration to add to the tea leaf extract This is the case.

As a result of considering the above points, the metal ion concentration necessary for the product of the present invention is, for example, when zinc gluconate is used in the tea leaf extract of about Brix 0.3, the addition concentration is about 15 ppm to 20 ppm as the metal concentration. is there. At this concentration, the amount of zinc per liter of beverage will vary from 15 mg to 20 mg, and the green color of the product of the present invention is maintained within a reasonable range even when the above-mentioned daily nutritional requirement for zinc of 10 mg is considered. Can be confirmed.
It should be noted that other known methods such as addition of an antioxidant such as ascorbic acid as a stabilizer, deoxidation treatment of the extract, or nitrogen replacement treatment of the headspace of the product of the present invention are not permitted. Since there is an effect of further enhancing the effect, it may be used in combination as appropriate.
In addition, for example, assuming a mode in which the amount of beverage is limited, it goes without saying that the green stability is further enhanced by further increasing the concentration of addition.

In addition, when the influence of the addition of metals that must be considered as beverages on the taste was observed, in the case of zinc and copper, no influence on the taste was observed either immediately after the addition or after the storage test, even when added at 50 ppm. There was also an effect of stabilizing the good flavor of the product, and it was not necessary to limit the amount of zinc and copper added in consideration of the influence on the taste. Only when added in the form of metal-containing yeast, the taste of the yeast may be recognized depending on its concentration, but even in that case, by selecting a yeast with good flavor such as baker's yeast, it is rather good flavor for tea Can be used in a form that is substantially unaffected.

Furthermore, when using a metal-containing yeast, in addition to the embodiment in which the yeast is contained in the product as it is, the added yeast is removed from the beverage by clarifier treatment, centrifugation, filter treatment, etc. after the metal replacement treatment. Can also be widened by product design.
On the other hand, since zinc sulfate and the like are highly soluble, they can be added to the liquid added to the apparatus at the time of performing the low temperature extraction operation of tea leaves. However, since no fading of green color is observed during the low temperature extraction process, it can be said that it is usually more desirable in terms of process management to add the metal additive to the extract after completion of the extraction operation because the addition concentration is easier to manage.

  According to the present invention, it has become possible to stably provide a beautiful green color that is not found in conventional bottle beverages and provide a flavorful non-fermented tea (green tea) in a product form such as a bottle beverage. In particular, when the low temperature extract of tea leaves shown in Patent Document 5 is targeted, by performing an operation in which this extract is made to act on zinc ions or copper ions, the degree of greenness is clearly compared with that of commercially available green tea beverages. As a result, it has become possible to provide new bottled green tea beverages, which can be literally called green tea for the first time, to the market.

  A non-fermented tea leaf low-temperature extract having a high greenness and a good flavor, which is the base of the present invention, can be produced as a reference example of the example shown in Patent Document 5. The gist of the production method is to put non-fermented tea leaves such as Kabusecha into a biaxial extruder or colloid mill and pulverize the tea leaves. At that time, 50 ° C or less minus 5 ° C or more, preferably 40 ° C or less minus 5 ° C or more Preferably, an extraction treatment is performed with a low temperature solvent of 30 ° C. or lower minus 5 ° C. or higher, and then the extraction koji and the extract are separated to obtain a low temperature extract having a high greenness and a good flavor. In the case of this method, there is no rapid browning of chlorophyll etc. due to heating at the time of extraction like ordinary hot water extract products, and components related to green color and umami in tea leaves despite extraction at low temperature and short time Is extracted more than the hot water extract, for example, the a value measured with a color difference meter indicating the greenness is clearly -9 and the value as green (Table 1).

  The greenness of the product of the present invention is the green color exhibited by the non-fermented tea leaf extract, and is used to add green color to other additives such as green colorants, green tea, gyokuro powder, sencha powder, etc. It is not the greenness obtained as a result of the addition of pulverized tea leaves, pulverized green plants such as bitter gourd other than tea leaves. As a result of adding these, even if the greenness similar to that of the present invention product is obtained, it is the greenness realized as a result of adding the green additive, and the green color of the tea leaf extract of the present invention is stabilized. The technical significance is completely different from the greenness obtained. However, this does not deny an aspect in which bitter gourd powder other than ground tea leaves is added while the green color of the extract itself is essentially high and stabilized. This is because these materials may be added to add functionality to green tea.

  The green stabilizer used in the product of the present invention can be used in the form of zinc and / or copper gluconate, sulfate, metal-containing yeast and the like. Metal-containing yeasts are used as foods and are relatively easy to use in the products of the present invention. There is no great difference in the additive concentration as a metal depending on the kind of stabilizer, and a maximum of about 100 ppm can be used.

The greenness of the product of the present invention can be expressed by using the color difference a of the color tone in the Lab color difference meter according to Hunter's color difference formula as an index, and is characterized by a value a lower than that of a commercially available tea product in a container. For example, when the a value after storage test at 30 ° C for 30 days is near Brix 0.3, it is 2.5 to -11, 3.0 to -10 near Brix 0.5, 5.0 to -6 near Brix 0.8, Brix 1.0 or more The state of 6.0 to -5 can be maintained. If Brix is high, the amount of chlorophyll that needs to be stabilized increases, so increasing the amount of green stabilizer added increases the stabilization effect, but the upper limit of the amount added is a commercial product as to what kind of food is offered to the market In consideration of the above, etc., it may be determined within the range of 100 ppm mentioned above. In addition, since the ratio of the extracted components is different and the a value tends to be high when Brix is high, in the present invention, the a value to be reached after the storage test is set for each Brix in relation to Brix. . Therefore, the storage test conditions show the criteria for setting the a value at the beginning of the invention, and do not show the storage stability of the product of the present invention. Tables 2 to 4 show the results of studies on the greenness and flavor of the product of the present invention and the control product when stored at 4 ° C and 30 ° C.

以下に、本発明品の実施の態様を具体的に示して本発明をより詳細に説明するが本発明は以下の実施態様に限定されるものではない。

Hereinafter, the present invention will be described in detail by specifically showing embodiments of the present invention, but the present invention is not limited to the following embodiments.

[Example 1]
The tea leaves (kabuse tea) were pulverized and rapidly extracted in ion-exchanged water at 20 ° C. using a biaxial extruder. After adjusting the extract of this extract by rubbing with gauze to Brix 0.30%, 0.04% (w / v) zinc yeast (manufactured by Marine Bio, zinc content about 10%) or 0.01% (w / v) Zinc gluconate (manufactured by Fuso Chemical Co., Ltd., zinc content of about 14%) was added and sterilized by heating at 90 ° C. for 10 minutes. After sterilization, cooling, filling into PET bottles, and allowing to stand at 4 ° C, and examining the time-dependent color difference and flavor change of the extract, the zinc ion greenness retention effect and flavor retention effect were confirmed (Table 2). Table 3). In order to confirm the greenness retention effect, an a value was measured using a Lab color difference meter. In order to confirm the flavor retention effect, a sensory test was performed and evaluation was performed in five stages.
Measuring equipment Brix; ATAGO digital refractometer RX5000 Measuring temperature 20 ℃.
a value: Tokyo Denshoku Co., Ltd. Color Analyzer TC-1800J

[Example 2]
The tea leaves (kabuse tea) were pulverized and rapidly extracted in ion-exchanged water at 20 ° C. using a biaxial extruder. The extract obtained by solid-liquid separation of this extract with a decanter is adjusted to Brix 0.55%. After adding 0.12% sodium ascorbate as an antioxidant, zinc yeast is added so that the final zinc concentration is 0.002% (w / v). (Additional marine bio zinc content of about 10%) was added, followed by UHT heat sterilization at 140 ° C. for 3 seconds using a plate heat exchanger. The greenness and flavor after UHT heat sterilization were confirmed by examining the color difference and flavor of the extract after sterilization. Further, after filling a plastic bottle with an extract solution having a final zinc concentration of 0.002% (w / v), a storage test was conducted at 30 ° C. for a long period of time to examine changes in flavor and greenness due to warm storage (Table 4). The flavor was evaluated on a 5-level scale in the sensory test. In order to confirm the greenness retention effect, an a value was measured using a Lab color difference meter.

[Example 3]
Tea leaves (kabuse tea) were pulverized in a 20 ° C. ion exchange water using a twin screw extruder and rapidly extracted to prepare a tea leaf extract. After this extract was rubbed with gauze, adjusted to Brix 0.30%, 0.002% (w / v) zinc sulfate (zinc content about 40.5%), 0.002% (w / v) copper sulfate (copper content about 39.8%) was added. The green color retention effect of zinc ions was confirmed by examining the color difference between the added solution and the control solution after heating at 90 ° C. for 10 minutes. To confirm the greenness retention effect, an a value was measured using a Lab color difference meter (Table 5).

いずれの実施例でも本発明品は対照品に比べて明確な緑色保持効果を示し、保存試験結果から保存後の緑色保持効果に加えて風味維持効果も示すことが明らかとなった。

In any of the examples, the product of the present invention showed a clear green retention effect as compared with the control product, and it was revealed from the storage test results that it also showed a flavor maintenance effect in addition to the green retention effect after storage.

Claims (7)

The tea leaves were ground extraction with 50 ° C. below the low temperature solvent twin extruder or a colloid mill, after separation of the extracted grounds and extract prior Symbol extract, zinc yeast, copper yeast, zinc gluconate, gluconic copper, at least one green stabilizer, formed by heating after addition so as to 100ppm of 3ppm in metal concentration, the production of green unfermented tea is selected from the group consisting of zinc sulfate and copper sulfate Method. The method for producing green unfermented tea according to claim 1, wherein the green stabilizer is selected from the group consisting of zinc yeast, zinc gluconate and zinc sulfate . When the value of the color difference “a” of the color tone in the Lab color difference meter, which is manufactured by the manufacturing method according to claim 1 or 2, at least after the heat treatment, is from 0.1 to less than 0.4 in Brix, the value is 2.5 to minus 11. Is green unfermented tea. When the value of the color difference a of the color tone in the Lab color difference meter, which is manufactured by the manufacturing method according to claim 1 or 2, at least after heat treatment, is from 3.0 to minus 10 when Brix is 0.4 or more and less than 0.6. Is green unfermented tea. After the heat treatment, the value of the color difference a of the color tone in the Lab color difference meter is from 2.5 to minus 11 when Brix is 0.1 or more and less than 0.4, and when Brix is 0.4 or more and less than 0.6. 3.0 to minus 10, 5.0 to minus 6 when Brix is 0.6 or more and less than 1.0, and 6.0 to minus 5 when Brix is 1.0 or more and less than 2.0 The green non-fermented tea according to claim 3 or 4. The value of color difference a of the color tone in the Lab color difference meter after filling in the product container at 30 ° C. for 30 days is from 2.5 to minus 11 when Brix is 0.1 or more and less than 0.4, and Brix 0.4 When the value is less than 0.6, the value is 3.0 to minus 10. When Brix is 0.6 or more and less than 1.0, the value is 5.0 to minus 6. When Brix is 1.0 or more and less than 2.0, The green non-fermented tea according to any one of claims 3 to 5, which is 6.0 to minus 5. Product container, plastic bottle, can, paper pack, cup, bottle, a gable or Chiapakku, green unfermented tea of claim 6.