WO2011102156A1

WO2011102156A1 - Manufacturing method for raw tea material used in beverages

Info

Publication number: WO2011102156A1
Application number: PCT/JP2011/050191
Authority: WO
Inventors: 正巳笹目; 仁衣笠; 史弘伊東; 冬樹藤原; 章雄伊藤; 和則岡野谷
Original assignee: 株式会社伊藤園
Priority date: 2010-02-16
Filing date: 2011-01-07
Publication date: 2011-08-25
Also published as: CN102753030B; CN102753030A; AU2011216786A1; AU2011216786C1; AU2011216786B2; JP5681367B2; JP2011167091A

Abstract

Provided is a manufacturing method for a raw tea material used in beverages whereby degradation odors resulting from long-term storage of the tea beverage can be suppressed. The manufacturing method for the raw tea material is characterized by the inclusion of a step for subjecting the cuticular layer of tea leaves to a reduction treatment. One example of the cuticular layer reduction treatment is to bring the front and/or back surface(s) of the tea leaves into contact with hot water, which flows in a substantially horizontal direction onto the surface of the tea leaves at a speed of 20-120 m/min at a temperature of 60-100°C, for a period of 10-120 seconds.

Description

Method for producing raw tea for beverages

The present invention relates to a method for producing tea for beverages that can be suitably used as a raw material for tea beverages, particularly container-packed tea beverages filled in cans or PET bottles.

Traditionally, tea was usually brewed in a teapot and drunk on that day. However, at present, container-packed tea beverages filled in cans, PET bottles, and the like have become widespread and may be stored for a long period of time, in which case problems such as generation of off-flavors have occurred. Therefore, it has become important to suppress the oxidation and deterioration of beverages during the production and storage of tea beverages and to suppress the generation of off-flavors.

In Patent Document 1 below, after removing the cold water extract obtained by extracting teas with cold water of 20 ° C. or less, the remaining teas are re-extracted with hot water of 30 ° C. to 95 ° C. A method for producing tea beverages with reduced heated odor (retort odor) is disclosed.

In Patent Document 2 below, green tea leaves are extracted with water at -5 to 9 ° C (first step), and the extraction residue of the first step is extracted with hot water at 50 to 100 ° C (second step). A method for producing a green tea beverage has been disclosed in which the extract obtained in the step and the extract obtained in the second step are mixed and then sterilized to reduce the generation of off-flavor during heat sterilization. Yes.

JP-A-11-113491 Japanese Patent No. 3590027

It is said that there are cuticle layers on the front and back surfaces of tea leaves, which play a role in preventing excessive water evaporation and bacterial infection. The cuticle layer is said to contain a polymer of unsaturated fatty acid called cutin as a main component and a wax component in addition.
As a result of diligent research, the present inventor has found that by reducing the weight of the cuticle layer, it is possible to suppress the deterioration of tea leaves and to suppress the generation of off-flavors due to long-term storage of tea beverages, thereby achieving the present invention. It is a thing.

Therefore, an object of the present invention is to provide a method for producing raw tea for beverages, which can suppress the deterioration odor of tea beverages, particularly the deterioration odor due to long-term storage.

The method for producing a raw material tea for beverage according to the present invention includes a step of reducing the cuticle layer of tea leaves.

The method for producing raw tea for beverages of the present invention reduces the unsaturated fatty acid in the cuticular layer by reducing the cuticular layer of tea leaves, so that the tea beverage extracted from the raw tea produced by this method is deteriorated. This makes it difficult to suppress the generation of off-flavors.

Hereinafter, an embodiment of the method for producing a raw tea for beverages of the present invention will be described. However, the present invention is not limited to this embodiment.

The beverage tea according to an embodiment of the present invention includes a step of reducing the cuticle layer of tea leaves.

In order to produce the raw material tea for beverages of the present invention, for example, the cuticle layer is reduced to the picked tea leaves, and using the treated tea leaves, the same steaming treatment, squeezing treatment, and Raw material tea (raw tea) can be manufactured by performing a drying process. This raw tea may be further processed.

The cuticle layer is said to exist on the front and back surfaces of tea leaves, and is said to have a function of preventing excessive water evaporation and bacterial infection. It is mainly composed of a polymer of unsaturated fatty acids called cutin and other waxes. It is said to contain ingredients. Unsaturated fatty acids become fatty acid degradation products, which are considered to cause a deteriorated odor generated during long-term storage of tea beverages. In the present invention, the deterioration odor can be suppressed by reducing the cuticle layer mainly composed of cutin.

The tea leaves as used in the present invention indicate fresh leaves, tea steamed leaves, or teacups, and if they are leaves or stems plucked from tea trees (scientific name: Camellia sinensis), the production area, cultivation method, plucking time, etc. are not limited, Any tea variety can be targeted.
More specifically, for example, varieties such as Yabukita, Yutaka Midori, Sayaka Kaori, Kanaya Midori, Okumidori, Samidori, Tsuyuhikari, Benifuuki, Fushushu and the like can be mentioned.

The raw material tea as referred to in the present invention broadly includes teas classified as non-fermented teas such as steamed tea, sencha, gyokuro, matcha, bancha, ball green tea, kettle roasted tea, and Chinese green tea. Includes blends.

The beverage referred to in the present invention is a liquid mainly composed of an extract or extract obtained by extracting the raw tea, for example, a liquid consisting only of an extract obtained by extracting tea leaves, or A liquid obtained by diluting an extract liquid, a liquid obtained by mixing extract liquids, a liquid obtained by adding an additive to any one of these liquids, or a liquid obtained by dispersing a dried one of these liquids. Can be mentioned. Moreover, the drink as used in the field of this invention includes the container-packed tea drink which filled the said liquid with the container. The container for filling the packaged tea beverage is not particularly limited, and for example, plastic bottles (so-called PET bottles), metal cans such as steel and aluminum, bottles, paper containers, and the like can be used. A transparent container such as a bottle can be preferably used.
The term “main component” includes the meaning that it is allowed to contain other components within a range that does not interfere with the function of the main component. At this time, although the content ratio of the main component is not specified, the extract or extract obtained by extracting green tea has a solid content concentration of 50% by mass or more, particularly 70% by mass or more in the beverage. Among these, it is particularly preferable to occupy 80% by mass or more (including 100%).

The reduction process of the cuticle layer of tea leaves is performed by introducing tea leaves into warm water flowing at a flow rate of 20 m / min to 120 m / min, preferably 30 m / min to 120 m / min, particularly preferably 60 m / min to 120 m / min. For 10 seconds to 120 seconds, preferably 15 seconds to 90 seconds, particularly preferably 30 seconds to 90 seconds.
This contact is preferably performed on either one or both of the front and back surfaces of the tea leaf, and may be brought into contact with the surface from any direction, but it is more preferable that hot water is brought into contact with the substantially horizontal direction. Thereby, the reduction rate of the cuticle layer can be increased.
The temperature of the hot water is preferably 60 ° C to 100 ° C, particularly preferably 70 ° C to 100 ° C, and more preferably 90 ° C to 100 ° C.

As a more specific method, for example, hot water is stored in a cylindrical container such as a 20 to 40 cm diameter pan and a circulatory flow is created so that a turbulent flow is generated by a pump or a stirring body, and tea leaves are placed in the circulatory flow. Furthermore, the weight of the cuticle layer can be reduced by collecting tea leaves after an appropriate time.
In addition, the flow velocity in the case where the hot water is circulated and brought into contact with the tea leaves in this way indicates a flow velocity at a position of about 8 cm from the center of the container.
In addition, for example, a pipe having an inner diameter of 23.0 mm is connected to a pump, hot water is circulated in the pipe, tea leaves are supplied from the supply port of the pipe, and flow through the pipe to be discharged from the discharge port. The weight of the cuticle layer can be reduced. At this time, the contact time between the tea leaves and the hot water can be adjusted by adjusting the flow rate of the hot water or the length of the pipe.

When the cuticle layer reduction process is performed using a pipe, it is preferable that there is a speed difference between the hot water flowing in the pipe and the tea leaves, and the flow is performed in a state (turbulent flow) showing irregular streamlines. For example, Re = DV / ν (D: pipe inner diameter, V: average flow velocity, ν: kinematic viscosity coefficient), and the Reynolds number indicating the nature of the flow is Re> 30,000, especially Re> 70,000. It is preferable to adjust so that it becomes.
The flow of tea leaves and hot water that are mixed and moving irregularly and showing irregular streamlines is called turbulent flow, and the flow of tea leaves and hot water that maintain regular streamlines is called laminar flow. .

The reduction rate of the cuticle layer is preferably 8% to 40%. In addition, the reduction rate of the cuticle layer indicates a reduction ratio of the weight of the cuticle layer of the tea leaf after the treatment to the weight of the cuticle layer of the tea leaf before the cuticle layer reduction treatment.
Generation | occurrence | production of the deterioration odor after a long-term storage can be suppressed as a reduction rate is 8% or more, and it will become a raw material tea excellent in flavor as it is 40% or less.
From this viewpoint, the reduction rate of the cuticle layer is particularly preferably 10% to 40%, and more preferably 15% to 30%.
In order to adjust the reduction rate of the cuticle layer, the temperature and flow rate of hot water, the contact time between tea leaves and hot water, etc. may be adjusted as appropriate. More specifically, if the temperature of the hot water is increased, the flow rate of the hot water is increased, and the contact time is increased, the reduction rate of the cuticle layer is increased.

The tea leaves after the cuticle layer reduction treatment preferably have a ratio of cuticle layer weight to cuticle fiber weight (cuticle layer / fiber) of 0.45 to 3.00.
Thereby, it becomes a raw material tea for drinks suitable for long-term storage and excellent in flavor.
From this viewpoint, the ratio of the cuticular layer weight of the tea leaves to the fiber weight of the tea leaves (cuticle layer / fiber) is particularly preferably 0.50 to 2.80, and more preferably 0.80 to 2.00.
In order to adjust this ratio, the temperature of the hot water, the flow rate, and the contact time with the tea leaves may be adjusted as appropriate in the cuticle layer reduction process.

In the raw tea of the present invention, the ratio of the weight of sucrose to the weight of the savory components of oxalic acid and caffeine (sucrose / savory component) is preferably 0.45 to 2.15.
Oxalic acid is an ingredient that makes you feel astringent, caffeine is an ingredient that makes you feel bitter, and sucrose is an ingredient that makes you feel sweet. By adjusting these weights, it becomes a raw tea that can feel a moderate taste.
From this viewpoint, the ratio of the weight of sucrose to the weight of the taste component of the raw tea is particularly preferably 0.60 to 2.00, more preferably 0.80 to 1.80.
In order to adjust this ratio, the temperature of the hot water, the flow rate of the hot water, and the contact time between the hot water and the tea leaf may be appropriately adjusted in the cuticle layer reduction process. More specifically, if the flow rate of hot water is increased and the contact time is increased, the ratio of the weight of sucrose to the weight of the savory component increases, so that these may be adjusted as appropriate.

In the raw tea of the present invention, the weight of catechin is preferably 5 to 20% by weight in the raw tea.
Catechin is a component that gives astringency and bitterness. By adjusting this ratio, the tea becomes a raw tea that can feel a tea.
From this viewpoint, the ratio of the catechin in the raw tea is particularly preferably 7 to 18% by weight, and more preferably 9 to 17% by weight.
The catechins used in the present invention are catechin (C), gallocatechin (GC), catechin gallate (Cg), gallocatechin gallate (GCg), epicatechin (EC), epigallocatechin (EGC), epicatechin gallate ( ECg) and epigallocatechin gallate (EGCg).
In order to adjust this ratio, for example, it is possible to adjust the contact time between tea leaves and hot water in the cuticle layer reduction process, or to select the tea season of the tea leaves to be used.

In the raw tea of the present invention, the residual rate of catechin is preferably 85% to 100%. The catechin residual ratio indicates the ratio of the weight of catechin in the tea leaf subjected to the cuticle layer reduction treatment to the weight of the catechin in the tea leaf not subjected to the cuticle layer reduction treatment.
By making it in this range, it becomes a raw tea that can feel a tea feeling compared to untreated products.
From this viewpoint, the residual ratio of catechin is particularly preferably 90% to 100%, and more preferably 93% to 100%.
In order to adjust the remaining rate, for example, the contact time between tea leaves and warm water may be appropriately adjusted in the cuticle layer reduction process.

Measurement of the weight of the cuticle layer, fiber, sucrose, oxalic acid, caffeine, and catechin described above can be performed, for example, as shown in the following examples.

Tea beverages extracted from raw tea for beverages produced using raw tea leaves that have undergone cuticle layer reduction treatment have reduced unsaturated fatty acids and are less prone to degradation odors even if stored for long periods of time. In particular, it can be suitably used as a packaged tea beverage.

Hereinafter, examples of the present invention will be described. However, the present invention is not limited to this embodiment.

The following tests 1 to 6 were performed. The sucrose weight, catechin weight, caffeine weight, oxalic acid weight, cuticle layer weight, and fiber weight shown below were measured as shown below.

<Sucrose weight>
(1) Preparation method of sample 50 mg of pulverized raw tea was taken, 50 mg of ultrapure water was added thereto, and ultrasonic extraction was performed for 15 minutes. Take 500 μL of the extracted sample, add 100 μL of 100 mM sodium hydroxide (NaOH), 100 μL of 50 ppm lactose (Lactose), and 400 μL of ultrapure water, mix well, and use this as a high-performance liquid chromatogram (HPLC). The sucrose weight was measured by the calibration curve method under the following conditions.
(2) Analytical conditions / analytical column: HPLC sugar analyzer / column: Carbopack manufactured by Dionex
PA1 (4.6mm × 250mm) (P / N35391 manufactured by Dionex)
・ Column temperature: 30 ℃
・ Flow rate: 1.0mL / min
・ Gradient condition: See Table 1 below

<Catechin weight, caffeine weight>
By the following method, the content rate (mass%) of catechin or caffeine with respect to the whole dry tea leaf mass was measured.
(1) Sample Preparation Method 200 mg of the crushed raw tea was taken, 100 mL of 20% acetonitrile was added thereto, and ultrasonic extraction was performed for 60 minutes. The extract was filtered through a membrane filter (0.45 μm) to obtain a sample, which was quantified by the calibration curve method under the following conditions to measure the catechin weight or caffeine weight.
(2) Analysis conditions and analyzer: Xbridge made by Waters
shield RP18
3.5mm × 150mm
・ Column temperature: 40 ℃
・ Flow rate: 0.5mL / min
-Mobile phase: Phase A water, Phase B acetonitrile, Phase C 1% phosphoric acid-Injection volume: 5 μL
-Detector: UV detector UV230nm made by Waters
・ Gradient condition: See Table 2 below

<Oxalic acid weight>
100 mg of 100 g of a crushed raw tea was weighed into a 100 ml volumetric flask, 10 mL of 1N hydrochloric acid solution was added, and the volume was increased with distilled water. This was left for 30 minutes or longer as an extraction solution.
The extracted solution was filtered through a 0.45 μm filter, and the weight of total oxalic acid was measured using capillary electrophoresis using the filtrate as a sample.
The electrophoresis solution used was 20 mM quinolinic acid, 0.25 mM tetradecyltrimethylammonium hydroxide, and the pH was adjusted to 8.0 with 2MTris (2-amino-2-hydroxymethyl-1,3-propanediol). .

<Cuchikura layer weight>
Thirty tea leaves were punched into a disk shape with a cork borer having a diameter of 20 mm to produce 30 disks (3.14 cm ² per sheet). Thirty disks were immersed in the reaction solution and reacted at 40 ° C. for 24 hours. The reaction solution is a mixture of 20 ml of phosphate-citrate buffer (pH 3.0), 2 ml of cellulase (novozyme Celluclast 1.5 L) and 0.5 ml of pectinase (novozyme Pectinex Ultra SP-L). After the reaction, the transparent film (cuticle layer) on the surface of the disc was recovered from the front and back of the tea leaves, washed with an ultrasonic cleaner and freeze-dried, and the weight of 30 discs (94.2 cm ² ) was measured. The weight of the cuticle layer (mg) was calculated per 50 cm ² .

<Fiber weight>
After drying the tea leaves in a microwave oven, pulverizing them in a cyclone mill made by UDY CORPORATION, filling them in a dedicated cell, and then determining the fiber amount with an INSTALAB 600 tea component near infrared analyzer made by Shizuoka Seiki Co., Ltd. The fiber content (% by mass) was calculated and the fiber weight was measured.

<< Test 1 >>
In Test 1, the temperature change of the hot water was mainly changed, and the weight change of the cuticle layer was examined.
The following samples 1 to 5 were prepared using tea leaves (Yabukita variety) (No. 2 tea) as tea leaves.

(Sample 1)
The tea leaves were steamed, masticated, and dried in the same manner as in the past to prepare Sample 1 of crude tea.

(Sample 2)
10 L of normal temperature (about 20 ° C.) water was stored in a cylindrical container having a diameter of about 30 cm, and this water was rotated and stirred by a stirrer so that turbulent flow occurred, and circulated at a flow rate of about 60 m / min. A metal net containing 150 g of tea leaves was put into the container and exposed for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past to prepare Sample 2 of crude tea.

(Sample 3)
10 L of warm water of 90 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and a metal net containing 150 g of tea leaves was put into this container, so that the tea leaves were immersed and left for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past, and a crude tea sample 3 was produced.

(Sample 4)
10 L of warm water of 90 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and a metal net containing 150 g of tea leaves was put into the container, so that the tea leaves were immersed and left for 150 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past, and a crude tea sample 4 was produced.

(Sample 5)
10 L of 90 ° C. warm water was stored in a cylindrical container having a diameter of about 30 cm, and this water was rotated and stirred by a stirrer so that turbulent flow occurred, and circulated at a flow rate of about 60 m / min. A metal net containing 150 g of tea leaves was put into the container and exposed for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past to prepare Sample 5 of crude tea.

(Analysis test)
In sample 1, the cuticle layer weight of tea leaves after plucking was measured, and in samples 2 to 5, the cuticle layer weight of tea leaves after being collected from the container was measured. In addition, the catechin weight of the crude tea of Samples 1 to 5 was measured. These results are shown in Table 3 below.

(Beverage)
10 g of crude tea of each sample 1 to 5 was collected and extracted with 1000 ml of distilled water at 70 ° C. for 3.5 minutes. The residue was removed using a 150 mesh metal mesh. The extract was rapidly cooled to room temperature in ice water, and centrifuged (700 rpm, 10 minutes) using a Westphalia SA1 continuous centrifuge to remove insoluble fractions. Thereafter, L-ascorbic acid was added in an amount of 300 ppm with respect to the preparation volume (1000 ml), adjusted to pH 6.0 with sodium bicarbonate, and this preparation solution was UHT sterilized at 133 ° C. to 135 ° C. for 30 seconds. This was filled in a PET bottle and cooled to room temperature (about 25 ° C.) in running water to prepare a packaged tea beverage.

(Sensory test)
First, seven expert panelists evaluated the fresh aroma and taste of samples 1-5. Next, the panelists were allowed to drink the beverages prepared from Samples 1 to 5, and were evaluated for fresh flavor and taste. And two weeks later, the same beverage that was stored under the condition of 55 ° C. (for evaluation of the aging test) and the beverage that was stored under the condition of 4 ° C. (for the control of the aging test) Was drunk and evaluated for fresh scent, taste, and stability over time.
The evaluation is based on one of the following 1 to 4 points, and the average score of 7 panelists is “◎” when the average score is 3.5 or more, and “○” when 3 or more and less than 3.5. 2 or more and less than 3 were evaluated as “Δ”, and less than 2 as “x”. In addition, as a comprehensive evaluation, the average score of fresh aroma and taste was calculated for crude tea, and the average score of fresh aroma, flavor and stability over time was calculated for packaged tea beverages, and the same evaluation as above was performed. The test results are shown in Table 3 below.

<Fresh incense>
4 points = very strong 3 points = strong 2 points = slightly weak 1 point = weak

<Savory>
4 points = very good 3 points = good 2 points = slightly bad 1 point = bad

<Stability over time>
4 points = very high 3 points = high 2 points = slightly low 1 point = low

(Result of Test 1)
From Samples 2 to 5, it was confirmed that the temporal stability was improved by reducing the cuticle layer. From the results of Samples 3 and 4, it was confirmed that the cuticle reduction efficiency was poor just by immersing in warm water, and the catechin flowed out when immersed for a long time, resulting in slightly inferior taste evaluation. In addition, from the results of Sample 5, it was confirmed that the cuticle layer was efficiently reduced with running hot water, thereby maintaining a tea beverage suitable for long-term storage while maintaining the original flavor of tea.

<< Test 2 >>
In Test 2, the change in the reduction rate of the cuticle layer was examined mainly by changing how hot water was applied to the tea leaves.
The following samples 6 to 9 were prepared using tea varieties (No. 1 tea) from Shizuoka Prefecture as tea leaves.

(Sample 6)
The tea leaves were steamed, masticated, and dried in the same manner as in the past to prepare Sample 5 of crude tea.

(Sample 7)
Hot water at 80 ° C. was sprayed in a shower shape at a flow rate of about 30 m / min for 30 seconds from a direction substantially perpendicular to the tea leaf surface. The tea leaves were collected and rinsed lightly with tap water. Using this tea leaf, steaming, squeezing and drying were performed in the same manner as in the past to prepare Sample 6 of crude tea.

(Sample 8)
10 L of hot water at 80 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was circulated using a stirrer so as to become a laminar flow at a flow rate of about 1 m / min. A metal net containing 150 g of tea leaves was put into this container and exposed for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past to prepare Sample 8 of crude tea.

(Sample 9)
10 L of hot water at 80 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was rotationally stirred using a stirrer so that turbulent flow occurred, and circulated at a flow rate of about 30 m / min. A metal net containing 150 g of tea leaves was put into this container and exposed for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and using a total of 450 g of tea leaves, a steaming process, a mastication process, and a drying process were performed in the same manner as in the past to produce a crude tea sample 9.

(Analysis test)
In sample 6, the cuticle layer weight of the tea leaves after plucking is measured, in sample 7, the cuticle layer weight of the tea leaves after spraying warm water is measured, and in samples 8 and 9, the tea leaves collected from the container are measured. The cuticle layer weight was measured. From these measurement results, the cuticle layer reduction rate of each sample relative to the cuticle layer weight of sample 6 was calculated. Further, the catechin weight of crude tea of each sample 6 to 9 was measured, and the catechin residual ratio of each sample with respect to the catechin weight of sample 6 was calculated. These results are shown in Table 4 below.

(Beverage)
Using the crude tea of each sample 6 to 9, a packaged tea beverage was prepared in the same manner as in Test 1 above.

(Sensory test)
A sensory test was conducted in the same manner as in Test 1 above, except that the crude tea of each sample 6 to 9 and the tea beverage prepared from these were used and the beverage stored for one month was used for the time-lapse test. The test results are shown in Table 4 below.

(Result of Test 2)
Comparing samples 7 to 9, it was confirmed that the reduction rate of the cuticle layer was larger when the hot water was brought into contact with the tea leaves so that turbulent flow occurred. Moreover, it was confirmed that the residual rate of catechin does not change greatly from any direction.

<< Test 3 >>
In Test 3, changes in the reduction rate of the cuticle layer were examined mainly by changing the flow rate of hot water and the contact time between tea leaves and hot water.
The following samples 10 to 14 were prepared by using a Yabukita variety (No. 1 tea) produced in Shizuoka Prefecture as the tea leaves.

(Samples 10-14)
10 L of hot water of 80 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was rotationally stirred using a stirrer so as to cause turbulent flow and circulated at a flow rate shown in Table 5 below. A metal net containing 150 g of tea leaves was put into this container and exposed to the time shown below. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and a total of 450 g of tea leaves were subjected to the same steaming, squeezing, and drying treatments as in the past to prepare samples 10 to 14 of crude tea.

(Analysis test)
In Samples 10 to 14, the weight of the cuticle layer of the tea leaves after being collected from the container was measured, and the cuticle layer reduction rate of each sample with respect to the cuticle layer weight of Sample 6 in Test 2 was calculated. Further, the catechin weight of the crude tea of each sample 10 to 14 was measured, and the catechin residual ratio of each sample with respect to the catechin weight of the sample 6 of the test 2 was calculated. Furthermore, the sucrose weight, caffeine weight and oxalic acid weight of the crude teas of Samples 10 to 14 were measured, and the ratio of sucrose weight to the caffeine weight and oxalic acid weight (egg ingredient weight) (sucrose / egg ingredient) was determined. Calculated. These results are shown in Table 5 below.

(Beverage)
Using the crude tea of each sample 10 to 14, a packaged tea beverage was prepared in the same manner as in Test 1 above.

(Sensory test)
A sensory test was conducted in the same manner as in Test 1 above, except that the crude tea of each sample 10 to 14 and the tea beverage prepared from these were used, and a beverage stored for 1 month was used for the aging test. The test results are shown in Table 5 below.

(Result of Test 3)
It was confirmed that when the flow rate of warm water was high and the immersion time with warm water was long, the cuticle layer reduction rate increased, the catechin residual rate decreased, and the sucrose / egg taste component value increased. From the sensory evaluation, it was confirmed that the cuticle layer was too much or the catechin was reduced too much, and it was not good and there was an appropriate range.

<< Test 4 >>
In Test 4, crude tea was produced by changing the water temperature at which mainly the cuticle layer reduction treatment was performed, and changes in these sensory evaluations were examined.
The following samples 15 to 18 were prepared using a tea leaf variety (No. 3 tea) produced in Shizuoka Prefecture as tea leaves.

(Samples 15-18)
10 L of hot water having a temperature shown in Table 6 below was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was rotationally stirred using a stirrer so as to generate turbulent flow and circulated at a flow rate of 100 m / min. In this container, 150 g of tea leaves were put in a metal net and exposed for 90 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. This operation was performed three times, and a total of 450 g of tea leaves were subjected to the same steaming, squeezing and drying treatments as in the past to produce samples 15 to 18 of crude tea.

(Beverage)
Using the crude tea of each sample 15-18, a packaged tea beverage was prepared in the same manner as in Test 1 above.

(Sensory test)
Six expert panelists drank tea beverages made from each sample and evaluated the lower tea odor and taste. Two months later, the same beverage stored at 37 ° C. in the same panel (for evaluation of the aging test) and the beverage stored at 4 ° C. (for the control of the aging test) And were evaluated for lower tea odor, taste, and stability over time.
The evaluation is based on one of the following 1 to 4 points, and the average score of 6 panelists is 3.5 or higher for “◎”, and 3 or higher and lower than 3.5 for “○”. 2 or more and less than 3 were evaluated as “Δ”, and less than 2 as “x”. In addition, as a comprehensive evaluation, an average score of lower tea odor, taste, and temporal stability was calculated and evaluated in the same manner as described above. The test results are shown in Table 6 below.

<Lower tea odor>
4 points = very weak 3 points = weak 2 points = slightly strong 1 point = strong

<Savory>
4 points = very good 3 points = good 3 points = slightly bad 1 point = bad

(Result of Test 4)
As shown in Samples 16 to 18, it was confirmed that the tea beverage prepared from the tea leaves subjected to the cuticle layer reduction treatment at a water temperature of 60 ° C. to 100 ° C. has good sensory evaluation.

<< Test 5 >>
The following A to C treated tea leaves were subjected to a squeezing process and a drying process in the same manner as in the past, and crude tea was produced for each treatment and each tea season. Next, according to Table 7, crude teas 1 to 7 were produced, and these were extracted to produce tea beverages 1 to 7, and sensory evaluation was performed.

(Process A)
Steaming was performed on fresh tea leaves as before.

(Process B)
10 L of hot water at 100 ° C. was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was rotationally stirred using a stirrer so that turbulent flow occurred, and circulated at a flow rate of about 120 m / min. A metal net containing 150 g of tea leaves was put into the container and exposed for 90 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. A total of 450 g of tea leaves obtained by performing this operation three times were steamed as before.

(C treatment)
10 L of 90 ° C. warm water was stored in a cylindrical container having a diameter of about 30 cm, and this hot water was rotationally stirred using a stirrer to cause turbulent flow, and circulated at a flow rate of about 120 m / min. A metal net containing 150 g of tea leaves was put into the container and exposed for 30 seconds. Thereafter, the tea leaves were collected and rinsed lightly with tap water. A total of 450 g of tea leaves obtained by performing this operation three times were steamed as before.

(Combination)
Crude teas 1 to 7 were prepared by blending the crude teas obtained by the squeezing and drying treatments after the AC treatments in the proportions shown in Table 7 below.

(Analysis test)
The sucrose weight, caffeine weight, and oxalic acid weight of the crude teas 1 to 7 were measured, and the ratio of the sucrose weight to the caffeine weight and the oxalic acid weight (egg ingredient weight) (sucrose / egg ingredient) was calculated. In addition, the weight of catechins of crude tea 1-7 was measured. The results are shown in Table 8 below.

(sensory evaluation)
10 g of crude tea 1-7 was collected and extracted with 1000 ml of distilled water at 70 ° C. for 3.5 minutes. The residue was removed using a 150 mesh metal mesh. The extract was rapidly cooled to room temperature in ice water, and centrifuged (700 rpm, 10 minutes) using a Westphalia SA1 continuous centrifuge to remove insoluble fractions. Thereafter, L-ascorbic acid was added in an amount of 300 ppm with respect to the preparation volume (1000 ml), adjusted to pH 6.0 with sodium bicarbonate, and this preparation solution was UHT sterilized at 133 ° C. to 135 ° C. for 30 seconds. This was filled in a PET bottle and cooled to room temperature (about 25 ° C.) in running water to prepare tea drinks 1-7. The tea beverages 1 to 7 were stored at 25 ° C. for 5 months, and were used for sensory evaluation.

Seven expert panelists evaluated the flavor, taste, and stability over time.
The evaluation is based on one of the following 1 to 4 points, and the average score of 7 panelists is “◎” when the average score is 3.5 or more, and “○” when 3 or more and less than 3.5. 2 or more and less than 3 were evaluated as “Δ”, and less than 2 as “x”. In addition, as a comprehensive evaluation, an average point of aroma, taste, and temporal stability was calculated and evaluated in the same manner as described above. The test results are shown in Table 8 below.

<Odor>
4 points = very strong 3 points = strong 2 points = slightly weak 1 point = weak

(Result of test 5)
It was confirmed that the sensory evaluation was slightly inferior when the value of the sucrose / egg taste component of the crude tea was 0.43 or 2.21. From this result, it was confirmed that the value of the sucrose / egg taste component is preferably in the range of 0.45 to 2.15.

<< Test 6 >>
The following A to C treated tea leaves were subjected to a squeezing process and a drying process in the same manner as in the past, and crude tea was produced for each treatment and each tea season. Next, according to Table 9, crude tea 8-14 was prepared, and these were extracted to prepare tea drinks 8-14, and sensory evaluation was performed.
First, before producing crude tea, the cuticle layer weight and fiber weight of each tea leaf of each tea stage treated with AC were measured, and the cuticle layer / fiber values shown in Table 10 were calculated.

(Process A)
Steaming was performed on fresh tea leaves as before.

(Combination)
Crude teas obtained by performing the A to C treatments were blended in the proportions shown in Table 9 below to produce crude teas 8 to 14.

(Analysis test)
The sucrose weight, caffeine weight, and oxalic acid weight of the crude teas 8 to 14 were measured, and the ratio of sucrose weight to caffeine weight and oxalic acid weight (egg taste component weight) (sucrose / egg taste component) was calculated. The results are shown in Table 10 below.

(sensory evaluation)
10 g of crude tea 8-14 was collected and extracted with 1000 ml of distilled water at 70 ° C. for 3.5 minutes. The residue was removed using a 150 mesh metal mesh. The extract was rapidly cooled to room temperature in ice water, and centrifuged (700 rpm, 10 minutes) using a Westphalia SA1 continuous centrifuge to remove insoluble fractions. Thereafter, L-ascorbic acid was added in an amount of 300 ppm with respect to the preparation volume (1000 ml), adjusted to pH 6.0 with sodium bicarbonate, and this preparation solution was UHT sterilized at 133 ° C. to 135 ° C. for 30 seconds. This was filled in a PET bottle and cooled to room temperature (about 25 ° C.) in running water to prepare tea drinks 1-7. The tea beverages 8 to 14 were stored at 25 ° C. for 5 months, and were used for sensory evaluation.

Seven expert panelists evaluated the flavor, taste, and stability over time.
The evaluation was performed in the same manner as in Test 5 above. The test results are shown in Table 10 below.

(Result of test 6)
It was confirmed that the sensory evaluation was slightly inferior when the cuticle layer / fiber value of tea leaves was 0.42 or 3.23. From this result, it was confirmed that the value of the cuticle layer / fiber was preferably in the range of 0.45 to 3.00.

Claims

A method for producing tea for beverages, which includes a step of reducing the cuticle layer of tea leaves.
The beverage raw material according to claim 1, wherein the step of reducing the cuticle layer is a step of charging tea leaves into warm water flowing at a flow rate of 20 m / min to 120 m / min and contacting the hot water for 10 seconds to 120 seconds. Tea production method.
The method for producing a tea for beverage according to claim 2, wherein the temperature of the hot water is 60 ° C to 100 ° C.
The method for producing raw tea for beverages according to claim 2 or 3, wherein hot water is brought into contact with either one or both of the front and back surfaces of the tea leaf from a substantially horizontal direction.
5. The raw tea for beverage production according to any one of claims 1 to 4, wherein the ratio of the cuticle layer weight to the fiber weight (cuticle layer / fiber) is 0.45 to 3.00 in the tea leaves having the cuticle layer reduced. Method.
The beverage according to any one of claims 1 to 5, wherein a ratio of sucrose weight to sucrose component weight (sucrose / egg component) comprising oxalic acid and caffeine of the raw tea is 0.45 to 2.15. Of making raw tea for food.
A tea beverage containing an extract extracted from the raw tea produced by the production method according to any one of claims 1 to 6.