JP7228188B2 - tea production method - Google Patents

Description

The present invention relates to a method for producing tea. Specifically, it can be produced by a simple process, and the tea beverage extracted from tea leaves has a refreshing taste, a sweet aftertaste, and a fruit-like aroma and roasted aroma. The present invention relates to a method for producing tea by which a tea beverage with suppressed bitterness and astringency can be obtained.

BACKGROUND ART Conventionally, tea beverages extracted from tea leaves of a plurality of tea species, including green tea and black tea, have been popular as luxury goods.

In addition, representative tea species include green tea, black tea, white tea, yellow tea, oolong tea, black tea, and the like. In the process of producing tea leaves of each type of tea, the tea leaves undergo different processes depending on the type, resulting in a characteristic taste, aroma, etc. for each type of tea.

For example, in the case of green tea, oolong tea, etc., raw tea leaves are heated by steaming or roasting to suppress the oxidizing action of the tea leaves.

In the case of green tea, black tea, and the like, the tea leaves are kneaded by mechanical processing or the like. In black tea, rolling promotes oxidative fermentation of tea leaves. In the case of green tea, rough rolling, medium rolling, fine rolling, and the like are performed to shape the tea leaves by rubbing them while drying them.

In addition, tea beverages are required to have a plurality of variations in sweetness and flavor to suit consumer tastes. For example, in the method for producing a black tea extract described in Patent Document 1, an attempt is made to produce a black tea extract with reduced sweetness and bitterness in consideration of health considerations and drinking during meals.

Here, in the method for producing black tea extract described in Patent Document 1, in order to reduce volatile substances derived from black tea leaves that cause bitterness and astringency, black tea extract that has undergone a general black tea production method Then, it has a step of concentrating the black tea extract by performing a process such as concentration under reduced pressure.

JP 2012-147771 A

However, in the method for producing a black tea extract described in Patent Document 1, as described above, in order to suppress the bitterness and astringency, a step of concentrating the extract is added after the steps of a general method for producing black tea. Therefore, there is a problem that the manufacturing efficiency is deteriorated.

In addition, although there are various steps in conventional tea production methods, it is desired to reduce the number of steps as much as possible and to make it possible to produce tea leaves simply and in a short time.

In addition, in the conventional tea manufacturing method, there are cases where machines are required for processing, such as killing blue and kneading. can also be a barrier to

Considering the recent decline in the industrial population related to tea production and the accompanying increase in abandoned cultivated land, it is important to develop a simpler production method that can produce high-quality tea. can be said to be a problem.

In addition to black tea, there is a need for an easy-to-drink tea beverage with suppressed bitterness and astringency, not only for black tea but also for other types of tea.

The present invention has been invented in view of the above points, and can be produced by a simple process, and the tea beverage extracted from tea leaves has a refreshing taste and a sweet aftertaste. To provide a method for producing tea by which a tea beverage having fruit-like aroma and roasted aroma and suppressed bitterness and astringency can be obtained.

In order to achieve the above object, the tea production method of the present invention comprises a withering step of withering tea leaves, a withering step of withering and then damaging the tea leaves by shaking, and and a drying step of drying the tea leaves after standing, and the bitterness and astringency of the tea beverage extracted from the tea leaves that have undergone the drying step are suppressed. there is

Here, the moisture contained in the tea leaves can be removed by withering the tea leaves in the withering step. That is, the moisture contained in the raw tea leaves collected from the field can be removed, and the tea leaves can be withered and subjected to the next step.

In addition, after withering, the tea leaves are rubbed against each other to damage the tea leaves in the rocking process, thereby promoting fermentation and enhancing the aroma of the tea leaves.

In addition, in the standing step, after the tea leaves have been shaken, the tea leaves are piled up and left to stand, so that the temperature rises due to the respiration heat of the tea leaves, which contributes to the generation of a unique fruit-like sweet aroma. It is presumed that in this standing step, the enzymatic reaction progresses inside the tea leaves, causing a change in the components. In addition, the sugar content derived from tea leaves, for example, the sugar content that is relatively abundant in mature fresh leaves, is alleviated by the fermentation of the tea leaves, leading to a refreshing taste with a sweet aftertaste. It is assumed that

In addition, after wilting, the tea leaves are shaken to damage them, and after the tea leaves are shaken, the tea leaves are piled up and allowed to stand still, thereby generating or increasing sweet fruit-like aroma components. Inspired and can enhance the sweetness of tea beverages.

Also, in the drying step, by drying the tea leaves after allowing them to stand still, it is possible to remove moisture from the tea leaves and obtain tea leaves that can be stably stored. At this time, by drying at a slightly high temperature, a fragrant roasted aroma is generated and the sweetness is enhanced.

In addition, after rocking, the tea leaves are piled up and left to stand still, and after standing still, the drying process to dry the tea leaves eliminates the conventional processes such as killing, rolling, molding, or fermentation. , while suppressing the bitterness and astringency, the tea leaves can easily maintain a sweet and fragrant aroma.

That is, for example, when going through the green tea production process like the conventional manufacturing process of green tea and oolong tea, it is heated such as steaming or roasting, but after standing, it is possible to reach the drying process without going through the green tea. , it is possible to avoid that the taste or aroma of the tea leaves is greatly changed by heating during killing. Also, the machine used for killing blue becomes unnecessary.

In addition, for example, when the tea leaves are subjected to a rolling/forming process as in the conventional manufacturing process of green tea, black tea, etc., by rolling the tea leaves, the cell walls of the tea leaves are broken, and the shape and components of the tea leaves are changed. At this time, it becomes easy to extract the components that cause astringency inside the tea leaves, and the tea beverage tends to have a bitter and astringent taste. However, by allowing the tea leaves to stand still and then to the drying process without rolling, it is possible to suppress the astringency without breaking the cell walls of the tea leaves. Moreover, the machine used for kneading becomes unnecessary.

In addition, if the total polyphenol content measured by treating the tea leaves that have undergone the drying process under the following conditions (A) and (B) is 0.50 mg / mL or less in terms of gallic acid equivalent, in the tea beverage The bitterness and astringency are sufficiently suppressed.
(A) Cut the tea leaves with a No. 8 sieve and sieve them onto a No. 14 sieve, or cut the tea leaves with a No. 4 sieve.
(B) 3.0 g of tea leaves passed through (A) above are infused with 140 mL of hot water at 100° C. for 90 seconds.
That is, the content of polyphenols is low, and the bitterness and astringency of the tea beverage as a whole is suppressed. In addition, the amount of polyphenols that lead to coloration of the tea beverage is small, and a tea beverage with a refreshing taste can be obtained. Incidentally, the No. 8 sieve, No. 14 sieve or No. 4 sieve referred to here is a term that defines the size of the sieve used for cutting and sieving tea leaves by the number of meshes. , shows a sieve with 8 meshes in 1 inch (3.03 cm).

In addition, when the withering step includes a sunlight withering step of exposing the tea leaves to sunlight, the tea leaves are withered by sunlight, and dehydration stress and an increase in leaf temperature can activate enzymatic reactions inside the tea leaves. .

In addition, when the indoor withering step includes an indoor withering step in which the tea leaves are spread out and withered indoors after being exposed to sunlight, the tea leaves can be allowed to continue the fermentation action by removing the grassy smell and unfavorable taste of the tea leaves. As a result, the tea leaves can be imparted with a peculiar flavor and aroma.

Also, in the standing step, when the deposited tea leaves are wrapped in a resin sheet and left to stand still, the respiration heat of the tea leaves can be prevented from escaping and the moisture inside the tea leaves can be prevented from evaporating. As a result, the enzymatic reaction inside the tea leaves is further accelerated, and a unique sweetness and fruit-like sweet aroma are likely to occur.

In addition, when the tea leaves are left to stand still within the range of 1 hour to 5 hours in the standing step, the tea leaves are imparted with moderate sweetness and fruit-like sweet aroma, and the taste is sweet and well-balanced. can be

On the other hand, in the standing step, if the tea leaves are left to stand without standing (0 hour) or for less than 1 hour, the aroma and taste of the tea leaves will be bluish and lack sweetness. . Also, if the tea leaves are allowed to stand still for more than 5 hours, the aroma of the tea leaves will be excessively oxidized, and the taste will be poorly balanced with a lack of flavor.

In addition, in order to achieve the above object, the tea leaves of the present invention, when the aroma components of the extract extracted from the tea leaves are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard, nerolidol satisfies the following condition (a), and the ratio of the peak areas of benzeneacetaldehyde satisfies the following condition (b).
(a) nerolidol: 1.1 to 3.0,
(b) Benzeneacetaldehyde: 6.1-13.8
100 μl of 5 ppm 2-octanol was added as an internal standard, and the peak area of each aroma component was calculated as a relative peak area ratio to the peak area value of 100 of the internal standard. A tea leaf extract was obtained by infusing 3.0 g of tea leaves with 140 ml of hot water at 100° C. for 90 seconds.

Here, when the aroma components of the extract extracted from tea leaves are analyzed by gas chromatography mass (GC-MS), the ratio of the peak area of nerolidol to the peak area of the internal standard is 1.1 to 3.0. When the ratio of the peak area of benzeneacetaldehyde to the peak area of the internal standard is 6.1 to 13.8, the tea beverage has a sweet aftertaste and a fruit-like flavor. . As for the content of fragrance, nerolidol is an aromatic component that exhibits a "floral" fragrance, and benzeneacetaldehyde is an aromatic component that exhibits a "floral, honey, rose, and sweet" fragrance.

In addition, in order to achieve the above object, the tea leaves of the present invention, when the aroma components of the extract extracted from the tea leaves are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard, nerolidol The ratio of the peak areas of satisfies the following condition (a), and the ratio of the peak areas of 2-methylbutyraldehyde satisfies the following condition (b).
(a) nerolidol: 1.1 to 3.0,
(b) 2-methylbutyraldehyde: 0.7-2.1

Here, when the aroma components of the extract extracted from tea leaves are analyzed by gas chromatography mass (GC-MS), the ratio of the peak area of nerolidol to the peak area of the internal standard is 1.1 to 3.0. When the ratio of the peak area of 2-methylbutyraldehyde to the peak area of the internal standard is 0.7 to 2.1, the tea beverage has a sweet aftertaste and a fruit-like flavor. be able to. As for the content of the fragrance, nerolidol is an aromatic component that exhibits a "floral" fragrance, and 2-methylbutylaldehyde is an aromatic component that exhibits a "chocolate, malt, and green grass-like" fragrance.

In addition, in order to achieve the above object, the tea leaves of the present invention, when the aroma components of the extract extracted from the tea leaves are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard, nerolidol The ratio of the peak areas of satisfies the following condition (a), the ratio of the peak areas of benzeneacetaldehyde satisfies the following condition (b), and the ratio of the peak areas of 2-methylbutyraldehyde satisfies the following It is configured to satisfy the condition (c).
(a) nerolidol: 1.1 to 3.0,
(b) Benzeneacetaldehyde: 6.1-13.8
(c) 2-methylbutyraldehyde: 0.7-2.1
Here, when the aroma components of the extract extracted from tea leaves are analyzed by gas chromatography mass (GC-MS), the ratio of the peak area of nerolidol to the peak area of the internal standard is 1.1 to 3.0. The ratio of the peak area of benzeneacetaldehyde to the peak area of the internal standard is 6.1 to 13.8, and the ratio of the peak area of 2-methylbutyraldehyde to the peak area of the internal standard is 0.7 to 2. When it is .1, the tea beverage has a sweet aftertaste and a fruit-like flavor. As for the content of the fragrance, nerolidol has a “floral” fragrance, Benzeneacetaldehyde has a “floral, honey, rose, and sweet” fragrance, and (2-methylbutylaldehyde) has a “chocolate, It is an aromatic component that exhibits a malt, green grass-like scent.

In addition, when the total polyphenol content measured by treating the tea leaves under the following conditions (A) and (B) is 0.50 mg / mL or less in terms of gallic acid equivalent, the bitterness and astringency of the tea beverage is sufficient. is suppressed by
(A) Cut the tea leaves with a No. 8 sieve and sieve them onto a No. 14 sieve, or cut the tea leaves with a No. 4 sieve.
(B) 3.0 g of tea leaves passed through (A) above are infused with 140 mL of hot water at 100° C. for 90 seconds.
That is, the content of polyphenols is low, and the bitterness and astringency of the tea beverage as a whole is suppressed. In addition, the amount of polyphenols that lead to coloration of the tea beverage is small, and a tea beverage with a refreshing taste can be obtained.

In addition, when the aroma component of the extract extracted from tea leaves is analyzed by gas chromatography mass (GC-MS), the ratio of the peak area of methylheptenone to the peak area of the internal standard satisfies 0.7 to 3.6. In addition, the tea beverage has a sweet aftertaste and can have a fruit-like flavor. As for the content of the aroma, methylheptenone (5-Hepten-one, 6-methyl-) is an aroma component that exhibits the aroma of "black currant (cassis), boiled fruit, and citrus".

In addition, when tea leaves that have been opened are used as raw materials for tea leaves, tea leaves contain more sugar than growing tea leaves with a small opening degree, and the tea beverage is more likely to have sweetness and roasted aroma. . In addition, there is no need to pluck tea leaves at a timing when the opening degree is small, and the burden caused by concentration of the plucking timing of tea leaves can be reduced. The unfolded tea leaves referred to here mean tea leaves whose buds have completely opened and are no longer elongated.

In addition, when the tea leaves have a tencha-like shape, the tea leaves are dried without being rubbed, so that the cells are not broken and the bitter and astringent taste is suppressed when made into a tea beverage. . In addition, since the shape of the tea leaves is preserved, the ingredients in the tea leaves are gradually extracted, so that the tea beverage can be brewed effectively. For example, even after the 4th to 5th infusion, the tea beverage has a sufficient flavor.

The method for producing tea according to the present invention can be produced in a simple process, and the tea beverage extracted from tea leaves has a refreshing taste, a sweet aftertaste, and a fruit-like aroma. It is a method for obtaining a tea beverage with roasted aroma and suppressed bitterness and astringency.

1 is a flowchart showing steps of a method for producing tea according to an embodiment of the present invention; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention (hereinafter referred to as "embodiments") will be described with reference to the drawings for understanding of the present invention. A tea manufacturing method A, which is an example of a tea manufacturing method to which the present invention is applied, will be described.
The method for producing tea shown below is an example of the present invention, and the content of the present invention is not limited to this.

As shown in FIG. 1, the tea production method A includes the steps of sunlight withering (S1), indoor withering (S2), rocking green (S3), standing (S4) and drying (S5).

In the tea production method A, Yabukita, a green tea variety, is used as the tea leaf raw material variety. In addition, the first tea leaves are used as the picking season for tea leaves.

In sunlight withering (S1), the raw tea leaves are spread on a vinyl sheet or the like and exposed to sunlight. The processing time is about 5 to 45 minutes. By exposing the raw tea leaves to sunlight, the tea leaves are withered and moisture is removed, and the enzymatic reaction inside the tea leaves can be activated by dehydration stress and temperature rise.

Next, after passing through sunlight withering, the tea leaves are subjected to the step of indoor withering (S2). In the indoor withering, the tea leaf raw material is spread thinly on a shelf, basket, or the like, and withered in a room temperature room environment. Alternatively, it can be done using a fresh leaf container for tea. The processing time is about 6 hours to 30 hours.

By withering the tea leaves indoors, it is possible to further wither the tea leaves, remove moisture, remove the grassy smell of the tea leaves, and allow the tea leaves to continue the enzymatic reaction. As a result, the tea leaves can be imparted with a peculiar flavor and aroma.

Subsequently, after undergoing indoor withering, the tea leaves are subjected to the process of rocking green (S3). In Yusei, the tea leaves are spread out on a vinyl sheet or the like, and the tea leaves are stirred by hand while vibrating them, or the tea leaves are lifted and shaken off, rubbing the tea leaves against each other to create the surface of the tea leaves. hurt the

The processing time for the yosei is about 5 to 15 minutes. As a result, the tea leaves have a sweet taste and a sweet fruit-like aroma can be enhanced.

In addition, the withering can be done by hand, or by using a withering machine, a drum withering machine, or a machine with similar functions.

Further, the shaken tea leaves are subjected to the step of standing (S4). In the standing, the tea leaves are spread on a basket or the like, the tea leaves are piled up, the piled tea leaves are wrapped in a vinyl sheet, and the leaves are left standing while suppressing the release of moisture from the tea leaves. The processing time is about 6 hours to 30 hours.

In the stationary state, the processing time is about 1 to 5 hours. Also, the thickness of the tea leaves deposited is about 6 cm to 30 cm. As a result, the temperature rises due to the respiration heat of the tea leaves, and a unique sweetness and sweet fruit-like aroma can be generated. In addition, through the above-described steps of rocking and standing, sweet and sweet fruit-like aroma components can be generated or increased.

Next, the left tea leaves are subjected to a drying step (S5) using a dryer. In drying, tea leaves are treated with hot air in a commonly used dryer to remove moisture. The temperature of hot air during drying was about 95° C. to 110° C., and the treatment time was about 60 minutes.

Tea can be produced from raw material tea leaves through the above steps.

Here, one of the characteristics of the tea production method A is that after shaking the tea leaves, the tea leaves are left to stand for a certain period of time. Through this standing step, as described above, the temperature rises due to the respiration heat of the tea leaves, which promotes the generation of unique sweetness and sweet fruit-like aroma.

In addition, one of the characteristics of the tea production method A is that the tea leaves are subjected to a drying step after being left to stand still. That is, one of the characteristics is that after standing, the tea leaves are dried and produced without going through the steps of killing blue, rolling, molding, or fermentation, which are seen in conventional tea production methods.

This makes it possible, for example, to avoid changing the taste or aroma of the tea leaves due to heating during killing. In addition, the shape of the tea leaves is changed by rolling, and polyphenols, which have a unique bitterness and astringency such as catechins and proanthocyanidins, are extracted from the inside of the tea leaves, resulting in bitterness and astringency. can be avoided.

As a result, bitterness and astringency are suppressed, and a tea beverage having sweetness and roasted aroma can be obtained.

Here, it is not always necessary to adopt Yabukita as the tea leaf material variety. For example, the representative varieties of tea leaves cultivated in Japan are Asatsuyu, Yabukita, Benifuuki, Yamatomidori, Makinoharawase, Kanayamidori, Okumidori, Oiwase, Okuhikari, Meiryoku, Samidori, Komakage, Yamanami, Minekaori, Hatsumomiji, Benifuki, Benihomare, Benihikari, etc. may be employed. Furthermore, in the present invention, tea leaves of any variety cultivated around the world can be used without being limited to these varieties. The variety of tea leaves is not limited to green tea, and various tea leaf varieties such as black tea, white tea, yellow tea, oolong tea, and black tea can be used.

Moreover, it is not always necessary to use tea leaves of the first tea, and the tea leaves may be collected at any of the first tea, the second tea, the third tea, the fourth tea, or the autumn and winter bancha. In addition, the tea leaves may be used immediately after collection or may be used after being stored immediately after collection.

In the sunlight withering (S1), it is not always necessary to spread the tea leaf material on a vinyl sheet or the like, and the method is not particularly limited as long as the tea leaf material can be exposed to sunlight. In addition, the sunlight withering time can be appropriately selected in consideration of the influence of the amount of sunlight and the temperature. However, excessive sun exposure of the tea leaves should be avoided as this can result in leaf scorch or flavor defects.

In addition, the treatment time for sunlight withering is preferably in the range of 5 minutes to 45 minutes, and in the range of 10 minutes to 30 minutes, from the viewpoint of the rate of weight loss of tea leaves and the aroma or taste. It is more preferable to be

In addition, in the indoor withering (S2), the method is not particularly limited as long as the tea leaves can be withered in a room temperature room environment. A machine or the like that can control the environment can also be used. The processing time for indoor withering is preferably within the range of 6 to 30 hours, preferably 12 to 30 hours, from the viewpoint of reducing the weight of tea leaves and improving the aroma or taste. is more preferred.

Also, in the method of rubbing tea leaves together, the method is not particularly limited as long as the surfaces of the tea leaves are scratched and the aroma can be enhanced. In addition, from the viewpoint of improving the aroma or taste of tea leaves, the treatment time of the green tea is preferably within the range of 5 minutes to 15 minutes, more preferably within the range of 5 minutes to 10 minutes. .

In addition, in the still standing method, the method is not particularly limited as long as the tea leaves are deposited, the temperature is raised by the respiration heat of the tea leaves, and the tea leaves are left for a certain period of time. In addition, the treatment time for standing is preferably in the range of 1 hour to 5 hours, and in the range of 2 hours to 4 hours, in order to give the tea leaves a sweet aroma and improve the aroma or taste. It is more preferable to be

Also, in the still standing method, it is not always necessary to wrap the accumulated tea leaves with a vinyl sheet as long as the release of moisture from the tea leaves can be suppressed, and other methods can be adopted. For example, it is conceivable to store the tea leaves in a piled state in a resin bag having a low moisture permeability.

In addition, when the tea leaves are left still, the thickness of the tea leaves is preferably in the range of 6 cm to 30 cm, more preferably in the range of 6 cm to 20 cm, from the viewpoint of improving the aroma or taste of the tea leaves. It is even more preferable to be the same.

In drying, the machine or the like used for drying is not particularly limited as long as the tea leaves can be treated with hot air to remove moisture. In order to improve the flavor and taste of tea leaves, the drying treatment temperature is preferably in the range of 95°C to 110°C, more preferably in the range of 105°C to 110°C.

Tea can be produced from raw material tea leaves through the above-described tea producing method A.

Here, one of the characteristics of the tea production method A is that after shaking the tea leaves, the tea leaves are left to stand for a certain period of time. Through this standing step, as described above, the temperature rises due to the respiration heat of the tea leaves, which promotes the generation of unique sweetness and fruit-like aroma.

In addition, one of the characteristics of the tea production method A is that the tea leaves are subjected to a drying step after being left to stand still. That is, one of the characteristics is that after standing, the tea leaves are dried and produced without going through the steps of killing blue, rolling, molding, or fermentation, which are seen in conventional tea production methods.

This makes it possible, for example, to avoid changing the taste or aroma of the tea leaves due to heating during killing. In addition, the cells are broken by rolling, and polyphenols, which have a unique bitterness and astringency such as catechins and proanthocyanidins, are extracted from the inside of the tea leaves, which is the source of astringency, and a bitter and astringent taste is likely to occur. can be avoided.

As a result, bitterness and astringency are suppressed, and a tea beverage having sweetness, fruity aroma, and roasted aroma can be obtained.
Thus, in the tea production method A, although it is a simple process, it is possible to produce tea that is excellent in sweetness, fruit-like aroma, and roasted aroma, has a refreshing taste, and has suppressed bitterness and astringency. can be done.

As described above, the method for producing tea according to the present invention can be produced in a simple process, and the tea beverage extracted from tea leaves has a refreshing taste, a sweet aftertaste, and a fruity taste. It is a method for obtaining a tea beverage in which a similar aroma and roasted aroma are felt and bitterness and astringency are suppressed.
In addition, the tea leaves according to the present invention can be produced by a simple process, and the tea beverage extracted from the tea leaves has a refreshing taste, a sweet aftertaste, and a fruit-like aroma and roasted taste. The result is a tea beverage with a sense of incense and suppressed bitterness and astringency.

Examples of the present invention will be described below.

Samples of Examples and Comparative Examples of tea leaves, which are examples of tea leaves to which the present invention is applied, were prepared and evaluated as follows.

(1) Contents of Samples and Examination of Sunlight Withering First, tea leaf samples were prepared according to the following contents, and the presence and duration of sunlight withering was examined. Yabukita tea leaves were used as samples. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Sunlight withering (test section): 0 minutes, 5 minutes, 10 minutes, 15 minutes, 20 minutes, 30 minutes, 45 minutes, 60 minutes Indoor withering: 21 hours, natural withering Blue rocking: 10 minutes, rocking machine, 4 rpm
Stationary: 4 hours Drying: 60 minutes, dryer, hot air temperature 105°C
3.0 g of tea leaves that have undergone the above manufacturing process are infused in 140 ml of hot water at 100° C. for 90 seconds, sensory evaluation is performed by a panel of five examiners, and each item of aroma and taste is scored on a 5-point scale. A sensory test was conducted.
Regarding the sunlight withering time, 0 minutes (Comparative Example 1), 5 minutes (Example 1), 10 minutes (Example 2), 15 minutes (Example 3), 20 minutes (Example 4), 30 minutes ( Example 5), 45 minutes (Example 6), and 60 minutes (Example 7). Table 1 shows the results of the sensory test.

Examples 1 to 6 were evaluated as 4 points or more in terms of aroma and taste. In Examples 2 to 5, the total score for aroma and taste was 10 points, and most of the samples gave evaluation results indicating sweetness in terms of taste.

(2) Examination of content of sample and indoor withering First, tea leaf samples were prepared with the following contents, and the indoor withering time was examined. Kaori Miyama was used as a sample tea leaf. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Sunlight withering: 10 minutes Indoor withering (test group): 6 hours, 12 hours, 18 hours, 24 hours, 30 hours, 36 hours, exposed to continuous air blowing, and stirred every 6 hours.
Shaping blue: 10 minutes, shaking blue machine, 4 rpm
Stationary: 4 hours Drying: 40 minutes, dryer, hot air temperature 105°C
The same sensory test as in (1) above was performed on the tea leaves that had undergone the above manufacturing process.
Regarding the indoor withering time, 6 hours (Example 8), 12 hours (Example 9), 18 hours (Example 10), 24 hours (Example 11), 30 hours (Example 12), 36 hours ( Example 13). Table 2 shows the examination results of the sensory test.

Examples 8 to 12 were evaluated as 3 points or more in terms of aroma and taste. Moreover, in Examples 10 to 12, the total score of aroma and taste exceeded 10 points, and most of the samples gave evaluation results indicating sweetness in terms of taste.

(3) Contents of Samples and Examination of Turquoise First, tea leaf samples were prepared according to the following contents, and the presence or absence of turquoise and time were examined. Yabukita tea leaves were used as samples. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Warm air withering: Due to cloudy weather at the time of testing, 15 minutes of hot air withering was performed as an alternative to sunlight withering.
Indoor withering: 26 hours, natural withering Shaking blue (test area): 0 minutes, 5 minutes, 10 minutes, 15 minutes, 30 minutes, shaking machine, 4 rpm
Stationary: 4 hours Drying: 60 minutes, dryer, hot air temperature 105°C
The same sensory test as in (1) above was performed on the tea leaves that had undergone the above manufacturing process.
The rocking time was 0 minutes (Comparative Example 2), 5 minutes (Example 14), 10 minutes (Example 15), 15 minutes (Example 16), and 30 minutes (Example 17). Table 3 shows the examination results of the sensory test.

In Examples 14 to 16, the total score of aroma and taste exceeded 8 points, which was an evaluation result indicating sweetness in terms of taste.

(4) Examination of content of sample and standing still First, tea leaf samples were prepared according to the following contents, and the presence or absence of standing and the time of standing were examined. Kaori Miyama was used as a sample tea leaf. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Sunlight withering: 10 minutes Indoor withering: Exposed to continuous air blowing for 12 hours, and stirred every 6 hours.
Shaping blue: 10 minutes, shaking blue machine, 4 rpm
Stationary (test section): 0 hours, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours, 10 hours Drying: 40 minutes, dryer, hot air temperature 105°C
The same sensory test as in (1) above was performed on the tea leaves that had undergone the above manufacturing process.
Regarding the standing time, 0 hours (Comparative Example 3), 1 hour (Example 18), 2 hours (Example 19), 3 hours (Example 20), 4 hours (Example 21), 5 hours ( Example 22), 6 hours (Example 23), 8 hours (Example 24), and 10 hours (Example 25). The results of the sensory test are shown in Table 4 (indoor withering 12 hours).

Examples 18 to 22 resulted in a total score of more than 6 points for aroma and taste. Moreover, in Example 18, the evaluation result was that the aroma was sweet.

(5) Investigation of contents of sample and deposit thickness at rest First, tea leaf samples were prepared with the following contents, and the deposit thickness at rest was examined. Yabukita tea leaves were used as samples. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Sunlight withering: 30 minutes Indoor withering: Exposure to continuous air blowing for 26 hours.
Shaping blue: 10 minutes, shaking blue machine, 4 rpm
Standing: 3 hours Deposit thickness of tea leaves when standing (test area): 3 cm, 6 cm, 10 cm, 20 cm, 30 cm, 40 cm, 50 cm
Drying: 60 minutes, dryer, hot air temperature 105°C
The same sensory test as in (1) above was performed on the tea leaves that had undergone the above manufacturing process.
Regarding the thickness of tea leaves deposited at rest, 3 cm (Example 26), 6 cm (Example 27), 10 cm (Example 28), 20 cm (Example 29), 30 cm (Example 30), 40 cm ( Example 31) and 50 cm (Example 32). Table 5 shows the examination results of the sensory test.

Examples 27 to 30 were evaluated as 4 points or more in terms of aroma and taste. Moreover, in Examples 27 to 30, the total score of aroma and taste was more than 9 points.

(6) Investigation of Contents of Samples and Drying Temperature First, tea leaf samples were prepared according to the following conditions, and the drying temperature was examined. Yabukita tea leaves were used as samples. Autumn buds of tea leaves were plucked and subjected to the following production steps.
Sunlight withering: 30 minutes Indoor withering: Exposure to continuous air blowing for 26 hours.
Shaping blue: 10 minutes, shaking blue machine, 4 rpm
Stationary: 4 hours Drying: 60 minutes, only 80°C for 80 minutes Dryer hot air temperature (test section): 80°C, 95°C, 110°C, 125°C
The same sensory test as in (1) above was performed on the tea leaves that had undergone the above manufacturing process.
The drying temperature was 80° C. (Example 33), 95° C. (Example 34), 110° C. (Example 35), and 125° C. (Example 36). Table 6 shows the examination results of the sensory test.

Examples 33 to 35 were evaluated as 3 points or more in terms of aroma and taste. Moreover, in Examples 34 and 35, the total score of aroma and taste was more than 8 points.

(7) Content of total polyphenols in the infusion Prepare tea leaf materials (Yabukita) from the same field at different times of harvesting tea leaves, and use tea production method A, which is the tea production method of the present invention, or conventional Tea was produced by subjecting it to the method for producing Tamaryokucha, and the total polyphenol content in the infusion was measured by adjusting the infusion under the following infusion conditions.
Similarly, tea leaf raw materials (benifuuki) with different tea leaf harvesting times are prepared, and subjected to the tea production method A, which is the tea production method of the present invention, or the conventional black tea production method, to produce tea. After production, the leaching solution was prepared under the following leaching conditions, and the total polyphenol content in the leaching solution was measured.
(Tea leaf cutting conditions)
For tea leaves, the tea leaves after plucking are finely cut with a No. 8 sieve, then passed through a No. 14 sieve to remove fine powder and particles, and the tea leaves on the No. 14 sieve are leached under the following leaching conditions. , to obtain an exudate.
(Leaching conditions)
3.0 g of tea leaves were infused with 140 ml of hot water at 100° C. For the first infusion, 90 seconds after adding hot water, the infused liquid was used as a sample for measuring the total polyphenol content. As for the second infusion, hot water was added and the exudate after 60 seconds was used as a sample for measuring the total polyphenol content.
(Method for measuring total polyphenol content)
The total polyphenol content of each sample was measured by a known colorimetric method (Folin-Ciocalteu method). In this measurement method, the Folin's reagent is reduced by polyphenols and turns blue, and the absorbance is measured for quantification. In addition, in the quantification, a calibration curve was created with gallic acid (a type of polyphenol), and the total polyphenol content was quantified as the gallic acid equivalent value from the measured absorbance of each sample and the calibration curve.
Regarding the measurement results of the total polyphenol content, Table 7 shows the results of comparison between the tea production method A using Yabukita and the Tamaryoku tea production method, and Table 8 shows the tea production using Benifuuki. Figure 2 shows the results of a comparison between method A and black tea production.

In Examples 37 to 40, the total polyphenols content was below 0.50 (mg / ml), and in the tea beverages produced through the tea production method A to which the present invention was applied, the total polyphenols This resulted in a lower content. That is, it was found that the method for producing a tea beverage sufficiently suppresses the bitterness and astringency compared to the conventional method for producing Tamaryokucha (green tea).

Also in Examples 41 to 44, the total polyphenols content was below 0.50 (mg / ml), and in the tea beverages produced through the tea production method A to which the present invention was applied, As a result, the total polyphenols content decreased. That is, it was found that the method for producing a tea beverage sufficiently suppresses the bitterness and astringency compared to the conventional method for producing black tea.

(8) Gas Chromatography Mass (GC-MS) Analysis of Aroma Components Tea production method A, which is the tea production method of the present invention, by preparing tea leaf materials (Yabukita) plucked from the same field, Black tea, oolong tea and green tea (gyokuryokucha) were subjected to different production methods to produce tea, and the aroma components of each sample were analyzed by GC-MS under the following analysis method and analysis conditions. Table 9 shows the results for tea production method A (Example 45), black tea (Comparative Example 14), oolong tea (Comparative Example 15), and green tea (Tamaryokucha) (Comparative Example 16). In addition, Table 10 shows the results of GC-MS analysis of aroma components of teas of different harvesting locations, harvesting times, and cultivars by the tea manufacturing method A.

(analysis method)
In general, the pretreatment of tea-based flavor components is carried out by a column concentration method or the like. Here, the solid-phase microextraction method was used as a simple and rapid sample extraction, concentration, and chromatographic introduction method. For quantification, 2-octanol was added as an internal standard to the sample to be measured, and the peak area of each aroma component was determined as the relative peak area ratio to the internal standard.
More specifically, the following method was used.
Preparation of the sample was carried out by placing 3.0 g of the sample in a 140 mL black tea examination device, pouring hot water, and infusing for 90 seconds. 7.5 mL of this leachate was taken in a 20-mL vial, 3.0 g of sodium chloride and 100 μL of 5 ppm 2-octanol as an internal standard were added and sealed, followed by heating at 70° C. for 120 seconds to stabilize the inside of the vial. A collection tube was then inserted for 15 minutes to trap the aroma components in the headspace.
The collection tube trapping the aromatic component was inserted into the injection port of the gas chromatograph heated to 250° C., and the aromatic component was introduced into the column of the gas chromatograph for 2 minutes for analysis.
Polydimethylcyclohexane/carboxen/divinylbenzene manufactured by SUPELCO was used as a collection tube.
Regarding the analysis conditions of the gas chromatograph, the column used was DB-5 (60 m × 0.25 mm, film thickness 0.5 µm) manufactured by Agilent, and the column temperature was kept at 40 ° C. for 5 minutes, and then increased to 250 ° C. by 10 ° C. /min. The inlet temperature was 250° C. and the linear velocity was 50.0 cm/s. Mass spectrometry (MS) and flame ionization (FID) were used as detectors, MS for compound identification and FID for compound quantification. The relative peak area ratio to the internal standard was measured for the aroma components of each sample. Also, the peak area value of each aroma component was calculated as a value of the relative area ratio when the internal standard is 100. In addition, tr in Tables 9 and 10 indicates that the value was less than the minimum area although it could be detected.

In Examples 45-49, the ratio of the peak area of nerolidol to the peak area of the internal standard is 1.1-3.0, and the peak area of benzeneacetaldehyde to the peak area of the internal standard is is 6.1 to 13.8, and the ratio of the peak area of 2-methylbutylaldehyde to the peak area of the internal standard is 0.7 to 2.1.
In Runs 46-49, large values of each aroma component of nerolidol, benzeneacetaldehyde and 2-methylbutylaldehyde were confirmed.

Claims (11)

a withering step of withering the tea leaves;
After withering, the tea leaves are shaken and scratched, and
After shaking, a standing step of depositing tea leaves and standing still,
A drying step of drying the tea leaves after standing,
The withering step is
a sunlight withering process of exposing the tea leaves to sunlight;
After exposing to sunlight, having an indoor withering step of spreading and withering the tea leaves indoors,
The standing step includes
The accumulated tea leaves are wrapped in a resin sheet and left to stand,
In the drying step, tea leaves in a shape without twist are dried,
A method for producing tea, wherein the tea beverage extracted from the tea leaves that have undergone the drying step has suppressed bitterness and astringency. a withering step of withering the tea leaves;
After withering, the tea leaves are shaken and scratched, and
After shaking, a standing step of depositing tea leaves and standing still,
A drying step of drying the tea leaves after standing,
The withering step is
a sunlight withering process of exposing the tea leaves to sunlight;
After exposing to sunlight, having an indoor withering step of spreading and withering the tea leaves indoors,
The standing step includes
The accumulated tea leaves are wrapped in a resin sheet and left to stand,
The drying step includes drying the tea leaves whose tissue structure is maintained,
Tea beverages extracted from tea leaves that have undergone the drying process have suppressed bitterness and astringency
Method of making tea. The total polyphenol content measured by treating the dried tea leaves under the following conditions (A) and (B) is 0.50 mg / mL or less in terms of gallic acid equivalent.
The method for producing tea according to claim 1 or 2.
(A) Cut the tea leaves with a No. 8 sieve and sieve them onto a No. 14 sieve, or cut the tea leaves with a No. 4 sieve.
(B) 3.0 g of tea leaves passed through (A) above are infused with 140 mL of hot water at 100° C. for 90 seconds. When the aroma components of the extract extracted from the tea leaves that have undergone the drying process are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard,
The peak area ratio of nerolidol satisfies the following condition (a), and the peak area ratio of benzeneacetaldehyde satisfies the following condition (b):
The method for producing tea according to claim 1 or 2.
(a) nerolidol: 1.1 to 3.0,
(b) Benzeneacetaldehyde: 6.1-13.8 When the aroma components of the extract extracted from the tea leaves that have undergone the drying process are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard,
The peak area ratio of nerolidol satisfies the following condition (a), and the peak area ratio of 2-methylbutyraldehyde satisfies the following condition (b):
The method for producing tea according to claim 1 or 2.
(a) nerolidol: 1.1 to 3.0,
(b) 2-methylbutyraldehyde: 0.7-2.1 When the aroma components of the extract extracted from the tea leaves that have undergone the drying process are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard,
The peak area ratio of nerolidol satisfies the following condition (a), the peak area ratio of benzeneacetaldehyde satisfies the following condition (b), and the peak area ratio of 2-methylbutyraldehyde satisfies the following condition: Satisfy the following condition (c)
The method for producing tea according to claim 1 or 2.
(a) nerolidol: 1.1 to 3.0,
(b) Benzeneacetaldehyde: 6.1-13.8
(c) 2-methylbutyraldehyde: 0.7-2.1 When the aroma components of the extract extracted from the tea leaves that have undergone the drying process are analyzed by gas chromatography mass (GC-MS), the peak area of the internal standard,
The ratio of the peak areas of methylheptenone satisfies the following condition (a):
7. The method for producing tea according to claim 4, claim 5 or claim 6.
(a) methylheptenone: 0.7 to 3.6 The standing step includes
Allow the tea leaves to stand within the range of 1 to 5 hours.
A method for producing tea according to any one of claims 1 to 7. The variety of tea leaves is Yabukita or Benifuuki.
The method for producing tea according to any one of claims 1 to 8. Using the tea leaves of the opening as the raw material for the tea leaves
A method for producing tea according to any one of claims 1 to 9. Tea leaves have a tencha-like shape
A method for producing tea according to any one of claims 1 to 10.

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