Preparation method of chestnut-flavored green tea
By finely controlling the tea processing technology, including spreading, oxygen-enriching treatment, greening, rolling, baking and ingredient extraction, the problem of unstable production quality of Lixiang green tea is solved, and high-quality and high-value production of tea is achieved.
Patent Information
- Application Number
- CN202411903352.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2025-02-07
AI Technical Summary
The lack of standardized production methods for Lixiang green tea in the prior art, resulting in unstable large-scale production quality.
Through fine process research, the spreading, rolling and baking parameters of tea are accurately controlled, the integrity and fragrance stability of tea are improved, and the stable release of chestnut fragrance is promoted. Specific steps include spreading, oxygen-enriching treatment, finishing, natural cooling, rolling and drying, natural cooling, fragrance extraction and grading treatment.
The quality controllable and stable aroma of tea has been achieved, and the economic value and market competitiveness of tea have been improved.
Abstract
Description
Technical Field
[0001] The invention relates to the field of tea processing, in particular to a method for preparing chestnut-flavored green tea. Background Art
[0002] "Guizhou Chestnut Fragrance Tea" has the classic characteristics of "Guizhou Green Tea" with emerald green color, tender chestnut fragrance, and strong and refreshing taste, especially with its high-quality characteristics of rich and lasting fragrance. It is made from the fine tea tree varieties, Guizhou Tea No. 1, with one bud and one leaf or one bud and two leaves just beginning to unfold. The dry tea leaves are tight and tender green, the soup color is tender green and bright, the chestnut fragrance is strong and lasting, and it is fresh and sweet. It has a very high market value. However, in the current technology, there is a lack of standardized production of chestnut-scented green tea. How to mass-produce chestnut-scented green tea with stable quality is an urgent problem to be solved. Summary of the invention
[0003] The purpose of the present invention is to provide a method for preparing chestnut-flavored green tea, through fine process research, accurately controlling the spreading, rolling, and baking parameters of tea leaves, improving the integrity of tea leaves, stabilizing the tea fragrance, promoting the stable release of chestnut flavor, and improving the economic value of tea leaves. The specific technical scheme is as follows: A method for preparing chestnut-flavored green tea comprises the following steps: (1) After the tea leaves are picked, they are placed in a spreading trough. The airflow temperature of the blower is 25°C-30°C. The temperature and air volume at the front and rear ends of the trough are consistent. The temperature is high first and then low. The air is blown intermittently. The air is blown for 60 minutes and then stopped for 15 minutes. The hot air is stopped 20 minutes to 25 minutes before the leaves fall, and the air is changed to natural air or stopped. The oxygen enrichment treatment is carried out for 20-25 minutes. (2) putting the tea leaves processed in the previous step into a tea-fixing machine; (3) The tea leaves are transferred to a cooling room for natural cooling and moisture recovery. The thickness of the leaves is controlled to be 10 cm to 15 cm, and the moisture recovery time is 60 min to 120 min. (4) Pour the tea leaves into the rolling machine and roll them. Gently press the finished product to fill the rolling barrel. Roll without pressure for 5 minutes. Then press until the barrel cover drops to 1 / 5-1 / 4 of the barrel height and roll for 10-25 minutes. Then control the barrel cover to drop to 1 / 3 of the barrel height and continue rolling for 0-20 minutes. Then, roll the barrel cover to drop to 1 / 5-1 / 4 of the barrel height and roll for 5 minutes. Roll without pressure for 5 minutes. (5) The tea leaves are transferred to the drum drying machine, the inner wall temperature of the drum feeding end reaches 160°C-170°C, the hot air temperature is 100°C-110°C, the leaf feeding amount is 80 kg / h-100 kg / h, and the time is 3min-5min; (6) Spreading the tea leaves treated in the previous step to cool naturally or by blowing natural wind indoors, with the thickness of the leaves being 15 cm to 20 cm and the moisture regaining time being 120 min to 180 min; (7) putting the tea leaves into a box-type aroma extractor at a temperature of 90°C-95°C, with the thickness of the leaves spread to 1 cm-2 cm, for 60 min-90 min; (8) Use a stem picker or color sorter to remove the tough stems, a winnowing machine to remove the yellow flakes and wool, a circular screen to separate the long and short, a shaking screen to separate the coarse and fine, and a winnowing machine to separate the light and heavy; a color sorter to separate the grades, and mix and package the tea in a uniform pile according to the quality requirements of the commercial tea.
[0004] Preferably, the oxygen-enriched treatment in step (1) is specifically performed by placing the tea leaves in a sealed can, injecting clean air so that the air pressure in the sealed can is 1.3-1.37 standard atmospheres, and maintaining the temperature at 30-33°C.
[0005] Preferably, the oxygen volume fraction of the clean air is 25-28%.
[0006] Preferably, in step (2), the inner wall temperature of the barrel feeding end of the withering machine is 250°C-260°C, and the duration is 120 s-150 s.
[0007] Preferably, after the tea leaves are treated by the withering machine in step (2), the grassy smell of the tea leaves is dissipated, the tea leaves are not sticky when pinched, the stems are not broken, the tea leaves feel good to the touch, the tea fragrance is revealed, and the moisture content is 45%-50%.
[0008] Preferably, the container for holding the tea leaves during the rehumidification in step (3) is any one of a bamboo container or a chain-type cooling and rehumidifying machine.
[0009] Preferably, after the moisture regaining in step (3), the tea leaves become soft and can be held in a ball without pricking the hand.
[0010] Preferably, after the rolling in step (4), the tea leaves are tightly rolled into tea strips, and the rolling leaf strip formation rate reaches more than 85%. After rolling, the leaves are deblocked using a deblocking machine depending on the condition of the leaves.
[0011] Preferably, the moisture content of the tea products after being treated by the roller drying machine in step (5) is 20% - 25%, the tea leaves are tightened and have a prickly feel.
[0012] Preferably, the moisture content of the tea products treated by the box-type aroma extractor in step (7) is ≤6%, the stems are broken, and the tea leaves can be turned into powder by twisting them with fingers.
[0013] Compared with the prior art, the technical effects of the present invention are embodied in: The present invention is based on local tea processing technology, combines the characteristics of fresh leaf raw materials in the producing area and the flavor differences of market products, optimizes the parameters of the chestnut-flavor green tea processing technology, thereby improving the processing efficiency of the tea, stabilizing the aroma and controlling the quality. DETAILED DESCRIPTION
[0014] The technical solution of the present invention is further defined below in conjunction with specific implementation methods, but the scope of protection required is not limited to the description.
[0015] Example 1 A method for preparing chestnut-flavored green tea comprises the following steps: (1) After the tea leaves are picked, they are placed in a spreading trough, the air flow temperature of the blower is 25°C, the temperature and air volume at the front and rear ends of the trough are consistent, the temperature is high first and then low, and the air is blown intermittently, blowing for 60 minutes and stopping for 15 minutes, and the hot air is stopped 20 minutes before the leaves fall, and natural air is blown or the air is stopped; oxygen enrichment treatment is performed for 20 minutes; the specific operation of the oxygen enrichment treatment is to place the tea leaves in a sealed can, inject clean air so that the air pressure in the sealed can is 1.3 standard atmospheric pressures, and maintain the temperature at 30°C; the oxygen volume fraction of the clean air is 25%; (2) feeding the tea leaves treated in the previous step into a tea-fixing machine; the inner wall temperature of the feeding end of the tea-fixing machine cylinder is 250° C., and the duration is 120 s; the tea leaves treated by the tea-fixing machine lose their grassy smell, are not sticky when pinched, and have a smooth feel, have a tea fragrance, and have a moisture content of 45%; (3) The tea leaves are transferred to a cooling room for natural cooling and rehumidification, the thickness of the leaves is controlled to be 10 cm, and the rehumidification time is 60 minutes; the container for holding the tea leaves during the rehumidification is any one of a bamboo container or a chain-type cooling and rehumidification machine; the tea leaves after the rehumidification become soft, and the tea leaves can be held in a ball without being prickly; (4) pouring tea leaves into a rolling machine for rolling, lightly pressing the finished product to fill the rolling barrel, rolling without pressure for 5 minutes, then pressing so that the barrel cover drops by 1 / 5 of the barrel height, rolling for 10 minutes; the barrel cover drops by 1 / 4 of the barrel height, rolling for 5 minutes; rolling without pressure for 5 minutes; after rolling, the tea leaves are tightly rolled, and the rolling leaf strip rate reaches more than 85%. After rolling, the leaves are deblocked using a deblocking machine according to the condition of the leaves; (5) The tea leaves are transferred to a roller dryer, the inner wall temperature of the cylinder feeding end reaches 160°C, the hot air temperature is 100°C, the leaf feeding amount is 80 kg / h, and the time is 3 minutes; the moisture content of the tea products treated by the roller dryer is 20%, the tea leaves are tightened, and have a strong thorny feel; (6) Spread the tea leaves treated in the previous step to cool naturally or with natural wind indoors, with a thickness of 15 cm and a moisture regaining time of 120 min; (7) putting the tea leaves into a box-type aroma extractor at a temperature of 90° C., spreading the leaves to a thickness of 1 cm, for 60 minutes; the moisture content of the tea products treated by the box-type aroma extractor is ≤ 6%, the stems are broken, and the tea leaves are turned into powder by twisting with fingers; (8) Use a stem picker or color sorter to remove the tough stems, a winnowing machine to remove the yellow flakes and wool, a circular screen to separate the long and short, a shaking screen to separate the coarse and fine, and a winnowing machine to separate the light and heavy; a color sorter to separate the grades, and mix and package the tea in a uniform pile according to the quality requirements of the commercial tea.
[0016] Example 2 A method for preparing chestnut-flavored green tea comprises the following steps: (1) After the tea leaves are picked, they are placed in a spreading trough, the air flow temperature of the blower is 30°C, the temperature and air volume at the front and rear ends of the trough are consistent, the temperature is high first and then low, and the air is blown intermittently, blowing for 60 minutes and stopping for 15 minutes, and the hot air is stopped 25 minutes before the leaves fall, and natural air is blown or the air is stopped; oxygen enrichment treatment is performed for 25 minutes; the specific operation of the oxygen enrichment treatment is to place the tea leaves in a sealed can, inject clean air so that the air pressure in the sealed can is 1.37 standard atmospheric pressure, and maintain the temperature at 33°C; the oxygen volume fraction of the clean air is 28%; (2) feeding the tea leaves treated in the previous step into a tea-fixing machine; the inner wall temperature of the feeding end of the tea-fixing machine cylinder is 260° C., and the duration is 150 s; the tea leaves treated by the tea-fixing machine lose their grassy smell, are not sticky when pinched, and have a tactile feel, have a tea fragrance, and have a moisture content of 50%; (3) The tea leaves are transferred to a cooling room for natural cooling and rehumidification, the thickness of the leaves is controlled to be 15 cm, and the rehumidification time is 120 minutes; the container for holding the tea leaves during the rehumidification is any one of a bamboo container or a chain-type cooling and rehumidification machine; the tea leaves after the rehumidification become soft, and the tea leaves can be held in a ball without being prickly; (4) pouring tea leaves into a rolling machine for rolling, lightly pressing the finished product to fill the rolling barrel, rolling without pressure for 5 minutes, then pressing so that the barrel cover drops to 1 / 5 of the barrel height, and rolling for 10 minutes; controlling the barrel cover to drop to 1 / 3 of the barrel height, and continuing to roll for 20 minutes; the barrel cover drops to 1 / 5 of the barrel height, and rolling for 5 minutes; rolling without pressure for 5 minutes; after rolling, the tea leaves are tightly rolled, and the rolling leaf strip rate reaches more than 85%, and after rolling, the leaves are deblocked using a deblocking machine according to the condition of the leaves; (5) The tea leaves are transferred to a roller dryer, the inner wall temperature of the drum feeding end reaches 170°C, the hot air temperature is 110°C, the leaf feeding amount is 100 kg / h, and the time is 5 minutes; the moisture content of the tea products treated by the roller dryer is 25%, the tea leaves are tightened, and have a strong thorny feel; (6) Spread the tea leaves treated in the previous step to cool naturally or with natural wind indoors, with a thickness of 20 cm and a moisture regain time of 180 min; (7) putting the tea leaves into a box-type aroma extractor at a temperature of 95° C., spreading the leaves to a thickness of 2 cm, for 90 minutes; the moisture content of the tea products treated by the box-type aroma extractor is ≤ 6%, the stems are broken, and the tea leaves are turned into powder by twisting with fingers; (8) Use a stem picker or color sorter to remove the tough stems, a winnowing machine to remove the yellow flakes and wool, a circular screen to separate the long and short, a shaking screen to separate the coarse and fine, and a winnowing machine to separate the light and heavy; a color sorter to separate the grades, and mix and package the tea in a uniform pile according to the quality requirements of the commercial tea.
[0017] Example 3 A method for preparing chestnut-flavored green tea comprises the following steps: (1) After the tea leaves are picked, they are placed in a spreading trough, the air flow temperature of the blower is 28°C, the temperature and air volume at the front and rear ends of the trough are consistent, the temperature is high first and then low, and the air is blown intermittently, blowing for 60 minutes and stopping for 15 minutes, and the hot air is stopped 23 minutes before the leaves fall, and the natural air is changed or the air is stopped; oxygen enrichment treatment is performed for 22 minutes; the specific operation of the oxygen enrichment treatment is to place the tea leaves in a sealed can, inject clean air so that the air pressure in the sealed can is 1.3 standard atmospheric pressures, and maintain the temperature at 30°C; the oxygen volume fraction of the clean air is 28%; (2) feeding the tea leaves treated in the previous step into a tea-fixing machine; the inner wall temperature of the feeding end of the tea-fixing machine cylinder is 260° C., and the duration is 150 s; the tea leaves treated by the tea-fixing machine lose their grassy smell, are not sticky when pinched, and have a tactile feel, have a tea fragrance, and have a moisture content of 50%; (3) The tea leaves are transferred to a cooling room for natural cooling and rehumidification, with the thickness of the leaves controlled to be 15 cm and the rehumidification time to be 60 minutes; the container for the tea leaves during the rehumidification is any one of a bamboo container or a chain-type cooling and rehumidification machine; the tea leaves after the rehumidification become soft, and the tea leaves can be held in a ball without being prickly; (4) pouring tea leaves into a rolling machine for rolling, lightly pressing the finished product to fill the rolling barrel, rolling without pressure for 5 minutes, then pressing so that the barrel cover drops to 1 / 4 of the barrel height, rolling for 10 minutes; controlling the barrel cover to drop to 1 / 3 of the barrel height, and continuing to roll for 10 minutes; the barrel cover drops to 1 / 5 of the barrel height, and rolling for 5 minutes; rolling without pressure for 5 minutes; after rolling, the tea leaves are tightly rolled, and the rolling leaf strip rate reaches more than 85%, and after rolling, the leaves are deblocked using a deblocking machine according to the condition of the leaves; (5) The tea leaves are transferred to a roller dryer, the inner wall temperature of the cylinder feeding end reaches 170°C, the hot air temperature is 110°C, the leaf feeding amount is 80 kg / h, and the time is 5 minutes; the moisture content of the tea products treated by the roller dryer is 20%, the tea leaves are tightened, and have a strong thorny feel; (6) Spread the tea leaves treated in the previous step to cool naturally or with natural wind indoors, with a thickness of 20 cm and a moisture regaining time of 120 min; (7) putting the tea leaves into a box-type aroma extractor at a temperature of 95° C., spreading the leaves to a thickness of 1 cm, for 90 minutes; the moisture content of the tea products treated by the box-type aroma extractor is ≤ 6%, the stems are broken, and the tea leaves are turned into powder by twisting with fingers; (8) Use a stem picker or color sorter to remove the tough stems, a winnowing machine to remove the yellow flakes and wool, a circular screen to separate the long and short, a shaking screen to separate the coarse and fine, and a winnowing machine to separate the light and heavy; a color sorter to separate the grades, and mix and package the tea in a uniform pile according to the quality requirements of the commercial tea.
[0018] Experimental example In order to further verify the technical effect of the present invention, comparative example 1 was set up, in which the tea leaves were not treated with oxygen enrichment during processing, and other operations were the same as in Example 1; comparative example 2, in which no pressure was applied during rolling, the rolling time was 30 minutes, and other operations were the same as in Example 1. Each group of tea leaves was processed and scored sensoryly, with a full score of 100 points. Boiled pure water was used during processing, the mass ratio of tea leaves to water was 7:100, and the soaking time was 8 minutes; the best shape of the tea leaves was round, tight, and green, and the best soup color was bright green; the best aroma was a long chestnut fragrance; and the best leaf bottom was bright green. The test tasting personnel were half male and half female, with a total of 48 people, and the scoring standard was GB / T23776--2009. The experimental results are as follows: shape Soup color aroma Leaf bottom Example 1 98.45 95.45 97.33 94.10 Example 2 96.03 98.26 93.39 95.66 Example 3 93.22 96.76 95.25 92.01 Comparative Example 1 86.33 81.08 84.20 85.29 Comparative Example 2 83.42 85.71 81.82 83.16 As can be seen from the table, after brewing the tea leaves of Examples 1-3 using the method of the present invention, the perception scores of the appearance, soup color, aroma, and leaf bottom are significantly higher than those of Comparative Examples 1-2. Since the enrichment treatment has a significant effect on the formation of tea aroma substances, it can accelerate the formation of small molecules in tea cells and bring a significant effect in the production of tea aroma quality, so the sensory score of the tea leaves in Comparative Example 1 is lower. Since the pressure control during kneading significantly affects the shape of the tea leaves, and the influence on the structure of the tea leaves directly determines the release of the tea aroma, the sensory score of the tea leaves in Comparative Example 2 is significantly reduced.
[0019] Each group of tea leaves was crushed, mixed with ethyl caprate and distilled water in a mass ratio of 1:0.05:100, soaked at room temperature for 20 minutes, frozen at -20℃ for 5 hours, boiled for 1 minute after thawing, kept at 40℃ for 3 minutes, and sampled for GC-MS analysis; the tea leaves were packaged and stored at room temperature for 3 months and then tested again. The results are as follows: Nerolidol content (mg / L) Nerolidol content after storage (mg / L) Example 1 3.34 3.11 Example 2 3.01 2.89 Example 3 3.42 3.23 Comparative Example 1 2.67 2.24 Comparative Example 2 2.89 2.35 As can be seen from the table, the nerolidol content of Examples 1-3 using the method of the present invention is higher, and the loss rate after long-term storage is small, while the loss rate of Comparative Examples 1-2 is large. It is obvious that the method of the present invention effectively improves the stability of tea aroma.
Claims
1. A method for preparing chestnut-flavored green tea, characterized in that: The steps include: (1) After the tea leaves are picked, they are placed in a spreading trough. The airflow temperature of the blower is 25°C-30°C. The temperature and air volume at the front and rear ends of the trough are consistent. The temperature is high first and then low. The air is blown intermittently. The air is blown for 60 minutes and then stopped for 15 minutes. The hot air is stopped 20 minutes to 25 minutes before the leaves fall, and the air is changed to natural air or stopped. The oxygen enrichment treatment is carried out for 20-25 minutes. (2) putting the tea leaves processed in the previous step into a tea-fixing machine; (3) The tea leaves are transferred to a cooling room for natural cooling and moisture recovery. The thickness of the leaves is controlled to be 10 cm to 15 cm, and the moisture recovery time is 60 min to 120 min. (4) Pour the tea leaves into the rolling machine and roll them. Gently press the finished product to fill the rolling barrel. Roll without pressure for 5 minutes. Then press until the barrel cover drops to 1 / 5-1 / 4 of the barrel height and roll for 10-25 minutes. Then control the barrel cover to drop to 1 / 3 of the barrel height and continue rolling for 0-20 minutes. Then, roll the barrel cover to drop to 1 / 5-1 / 4 of the barrel height and roll for 5 minutes. Roll without pressure for 5 minutes. (5) The tea leaves are transferred to the drum drying machine, the inner wall temperature of the drum feeding end reaches 160°C-170°C, the hot air temperature is 100°C-110°C, the leaf feeding amount is 80 kg / h-100 kg / h, and the time is 3min-5min; (6) Spreading the tea leaves treated in the previous step to cool naturally or by blowing natural wind indoors, with the thickness of the leaves being 15 cm to 20 cm and the moisture regaining time being 120 min to 180 min; (7) putting the tea leaves into a box-type aroma extractor at a temperature of 90°C-95°C, with the thickness of the leaves spread to 1 cm-2 cm, for 60 min-90 min; (8) Use a stem picker or color sorter to remove the tough stems, a winnowing machine to remove the yellow flakes and wool, a circular screen to separate the long and short, a shaking screen to separate the coarse and fine, and a winnowing machine to separate the light and heavy; a color sorter to separate the grades, and mix and package the tea in a uniform pile according to the quality requirements of the commercial tea.
2. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: The specific operation of the oxygen enrichment treatment in step (1) is to place the tea leaves in a sealed can, inject clean air so that the air pressure in the sealed can is 1.3-1.37 standard atmospheres, and maintain the temperature at 30-33°C.
3. The method for preparing chestnut-flavored green tea according to claim 2, characterized in that: The oxygen volume fraction of the clean air is 25-28%.
4. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: In step (2), the inner wall temperature of the barrel of the withering machine at the feeding end is 250° C.-260° C., and the duration is 120 s-150 s.
5. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: After the tea leaves are treated by the withering machine in step (2), the tea leaves lose their grassy smell, are not sticky when pinched, have a stalk that is not broken, have a good touch, have a strong tea fragrance, and have a moisture content of 45%-50%.
6. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: The container for holding the tea leaves during the rehumidification in step (3) is any one of a bamboo container or a chain-plate type cooling and rehumidifying machine.
7. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: After the moisture regaining step (3), the tea leaves become soft and can be held in a ball without pricking the hand.
8. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: After the rolling in step (4), the tea leaves are tightly rolled into tea strips, and the rolling leaf strip rate reaches more than 85%. After rolling, the tea leaves are deblocked using a deblocking machine depending on the condition of the leaves.
9. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: The moisture content of the tea products treated by the roller drying machine in step (5) is 20% - 25%, the tea leaves are tightened and have a prickly feel.
10. The method for preparing chestnut-flavored green tea according to claim 1, characterized in that: The moisture content of the tea products treated by the box-type aroma extractor in step (7) is ≤6%, the stems are broken, and the tea leaves can be turned into powder by twisting them with fingers.