Novel green production process of fresh tea

Abstract

The invention relates to the technical field of green tea production, and discloses a novel fresh tea green production process, which comprises the following steps: tea picking, spreading, green increasing, dehydration, strong light irradiation, rolling, freeze drying and packaging. By means of the technology, the components in the tea leaves can be effectively preserved, the content of tea polyphenol and other substances can be effectively kept through green increasing, strong light irradiation and freeze drying treatment, the taste of the green tea is improved, and the green tea has the good comprehensive performance of being fresh, refreshing, savoury, mellow and resistant to brewing. The green increasing and strong light irradiation process can effectively passivate polyphenol oxidase, and is a key step for improving the taste of the green tea. The process realizes full-mechanized and digital production, greatly reduces production components, and ensures the stability of product quality.

Description

Technical Field

[0001] The invention relates to the technical field of green tea production, in particular to a novel green production process for fresh tea. Background Art

[0002] Tea has been widely loved by people since ancient times for its unique aroma and flavor. Tea culture has developed in my country for thousands of years, and tea has become an indispensable part of people's daily life. Tea, tobacco, and alcohol have become essential gifts for visiting relatives and friends. It is also known as "China's Top Ten Famous Teas", and the value of tea has risen accordingly. People have higher and higher requirements for the quality of tea, the production process of tea is constantly improving, and the flavor of tea is becoming more and more abundant. The control of tea production costs and the retention of tea's own ingredients are the key to determining the quality and benefits of tea. Research investment in this area will promote the tea market. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies of the prior art, the present invention provides a new green production process for fresh tea.

[0005] (II) Technical solution

[0006] A new green production process for fresh tea comprises the following steps:

[0007] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality buds of tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain Festival. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails;

[0008] S2, spreading: spreading the picked fresh leaves at 20-30°C for 10-20h;

[0009] S3, greening: soak the spread fresh leaves in a greening liquid at a temperature of 30-35°C for 10-15 minutes, and use microwave treatment at the same time;

[0010] S4, dehydration: taking the fresh leaves after greening and performing centrifugal dehydration;

[0011] S5, strong light irradiation: the dehydrated fresh leaves are spread flat in a pulse strong light treatment room, 2 to 5 cm away from the light source, and subjected to pulse strong light flash treatment;

[0012] S6, rolling: the treated fresh leaves are put into a rolling machine and rolled for 10 to 30 minutes;

[0013] S7, freeze drying: put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them. After freezing, enter the negative pressure heating drying stage. The moisture content is maintained at 5-7%, and the drying is completed.

[0014] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0015] Preferably, the preparation method of the green enhancement liquid in step S3 is as follows: soak basalt, medical stone and hematite in pure water for 30 to 60 minutes, use microwave-assisted soaking with a power of 600 to 800 W, filter the filtrate after soaking to obtain the green enhancement liquid; the mass ratio of basalt, medical stone and hematite is 1:0.6 to 0.8:0.2 to 0.5.

[0016] Preferably, the centrifugal speed in step S4 is 800-1200 r / min.

[0017] Preferably, in step S5, the light intensity is 0.8 to 0.98 J / cm, and the number of flashes is 120 to 200 times.

[0018] Preferably, in step S7, the freezing temperature is -20 to -50°C, and the negative pressure heating and drying stage is 10 to 30Pa in the first stage and 20 to 60Pa in the second stage.

[0019] (III) Beneficial technical effects

[0020] A novel green production process for fresh tea comprises the following steps: tea picking, spreading, greening, dehydration, strong light irradiation, rolling, freeze drying and packaging.

[0021] The process of the present invention can effectively preserve the components inside the tea leaves, and can effectively maintain the content of tea polyphenols and other substances through greening, strong light irradiation, and freeze-drying treatment, thereby improving the taste of green tea, and having good comprehensive properties of freshness, fragrance, and resistance to brewing. The greening and strong light irradiation processes can effectively passivate polyphenol oxidase, which is a key step in improving the taste of green tea. The process realizes full mechanization and digital production, greatly reduces production components, and ensures the stability of product quality. DETAILED DESCRIPTION

[0022] Example 1

[0023] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality bud tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails.

[0024] S2. Spreading: Spread the picked fresh leaves at 20°C for 10 hours.

[0025] S3, blueing: soak basalt, medical stone and hematite in a mass ratio of 1:0.6:0.2 with pure water in a mass ratio of 1:1 for 30 minutes, use microwave-assisted soaking with a power of 600 W, and filter the filtrate after the soaking to obtain blueing liquid.

[0026] The spread fresh leaves were immersed in greening liquid at a temperature of 30°C for 10 minutes and simultaneously treated with microwaves at a power of 400W.

[0027] S4. Dehydration: The fresh leaves after greening are centrifuged for dehydration at a centrifugal speed of 800 r / min.

[0028] S5. Strong light irradiation: Spread the dehydrated fresh leaves flat in a pulsed strong light treatment room, 2 cm away from the light source, and perform pulsed strong light flash treatment. The light intensity is 0.8 J / cm and the number of flashes is 120 times.

[0029] S6. Rolling: The treated fresh leaves are put into a rolling machine and rolled for 10 minutes.

[0030] S7. Freeze drying: Put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them at a temperature of -20°C. After freezing, they enter the negative pressure heating and drying stage. The first stage is 10Pa and the second stage is 20Pa. The moisture content is maintained at 5%, and the drying is completed.

[0031] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0032] Example 2

[0033] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality bud tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails.

[0034] S2. Spreading: Spread the picked fresh leaves at 30°C for 20 hours.

[0035] S3, blueing: soak basalt, medical stone and hematite in a mass ratio of 1:0.8:0.5 with pure water in a mass ratio of 1:1 for 60 minutes, use microwave-assisted soaking with a power of 800 W, and filter the filtrate after the soaking to obtain blueing liquid.

[0036] The spread fresh leaves were immersed in greening liquid at a temperature of 35°C for 15 minutes and simultaneously treated with microwaves at a power of 600W.

[0037] S4. Dehydration: The fresh leaves after greening are centrifuged for dehydration at a centrifugal speed of 1200 r / min.

[0038] S5. Strong light irradiation: The dehydrated fresh leaves were spread flat in a pulsed strong light treatment room, 5 cm away from the light source, and subjected to pulsed strong light flash treatment. The light intensity was 0.98 J / cm, and the number of flashes was 200 times.

[0039] S6. Rolling: The treated fresh leaves are put into a rolling machine and rolled for 30 minutes.

[0040] S7, freeze drying: put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them at a temperature of -50°C. After freezing, they enter the negative pressure heating and drying stage. The first stage is 30Pa and the second stage is 60Pa. The moisture content is maintained at 7%, and the drying is completed.

[0041] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0042] Example 3

[0043] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality bud tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails.

[0044] S2. Spreading: Spread the picked fresh leaves at 25°C for 12 hours.

[0045] S3, blueing: soak basalt, medical stone and hematite in a mass ratio of 1:0.7:0.3 with pure water in a mass ratio of 1:1 for 40 minutes, use microwave-assisted soaking with a power of 700 W, and filter the filtrate after the soaking to obtain blueing liquid.

[0046] The spread fresh leaves were immersed in greening liquid at a temperature of 30°C for 10 minutes and simultaneously treated with microwaves at a power of 500W.

[0047] S4. Dehydration: The fresh leaves after greening are centrifuged for dehydration at a centrifugal speed of 1000 r / min.

[0048] S5. Strong light irradiation: Spread the dehydrated fresh leaves flat in a pulsed strong light treatment room, 3 cm away from the light source, and perform pulsed strong light flash treatment. The light intensity is 0.85 J / cm, and the number of flashes is 150 times.

[0049] S6. Rolling: The treated fresh leaves are put into a rolling machine and rolled for 20 minutes.

[0050] S7, freeze drying: put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them at a temperature of -30°C. After freezing, they enter the negative pressure heating and drying stage. The first stage is 20Pa and the second stage is 30Pa. The moisture content is maintained at 5%, and the drying is completed.

[0051] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0052] Example 4

[0053] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality bud tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails.

[0054] S2. Spreading: Spread the picked fresh leaves at 30°C for 15 hours.

[0055] S3, blueing: basalt, medical stone and hematite in a mass ratio of 1:0.8:0.4 are soaked in pure water in a mass ratio of 1:1 for 50 minutes, and microwave-assisted soaking is adopted with a power of 6000 W. After the soaking is completed, the filtrate is filtered to obtain blueing liquid.

[0056] The spread fresh leaves were immersed in greening liquid at a temperature of 35°C for 10 minutes and simultaneously treated with microwaves at a power of 400W.

[0057] S4. Dehydration: The fresh leaves after greening are centrifuged for dehydration at a centrifugal speed of 800 r / min.

[0058] S5. Strong light irradiation: The dehydrated fresh leaves were spread flat in a pulsed strong light treatment room, 5 cm away from the light source, and subjected to pulsed strong light flash treatment. The light intensity was 0.88 J / cm and the number of flashes was 180 times.

[0059] S6. Rolling: The treated fresh leaves are put into a rolling machine and rolled for 25 minutes.

[0060] S7, freeze drying: put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them at a temperature of -40°C. After freezing, they enter the negative pressure heating and drying stage. The first stage is 15Pa and the second stage is 40Pa. The moisture content is maintained at 7%, and the drying is completed.

[0061] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0062] Example 5

[0063] S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality bud tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails.

[0064] S2. Spreading: Spread the picked fresh leaves at 30°C for 18 hours.

[0065] S3, blueing: soak basalt, medical stone and hematite in a mass ratio of 1:0.6:0.2 with pure water in a mass ratio of 1:1 for 40 minutes, use microwave-assisted soaking with a power of 800 W, and filter the filtrate after the soaking to obtain blueing liquid.

[0066] The spread fresh leaves were immersed in greening liquid at a temperature of 30°C for 10 minutes and simultaneously treated with microwaves at a power of 600W.

[0067] S4. Dehydration: The fresh leaves after greening are centrifuged for dehydration at a centrifugal speed of 1000 r / min.

[0068] S5. Strong light irradiation: The dehydrated fresh leaves were spread flat in a pulsed strong light treatment room, 2 cm away from the light source, and subjected to pulsed strong light flash treatment. The light intensity was 0.9 J / cm and the number of flashes was 160 times.

[0069] S6. Rolling: The treated fresh leaves are put into a rolling machine and rolled for 30 minutes.

[0070] S7, freeze drying: put the rolled fresh leaves into the freezing chamber of the freeze dryer and freeze them at a temperature of -30°C. After freezing, they enter the negative pressure heating and drying stage. The first stage is 20Pa and the second stage is 50Pa. The moisture content is maintained at 6%, and the drying is completed.

[0071] S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

[0072] Comparative Example 1: Xinhua Yunwu Green Tea purchased on the market.

[0073] 1. Ingredient testing: The test results of the Tea Quality Supervision, Inspection and Testing Center of the Ministry of Agriculture and Rural Affairs are as follows:

[0074] Table 1

[0075]

[0076]

[0077] It can be seen from Table 1 that the contents of tea polyphenols, caffeine, theanine and vitamin substances in Examples 1 to 5 are all higher than those in Comparative Example 1.

[0078] 2. Sensory evaluation test: A sensory evaluation was performed on Examples 1 to 5 and Comparative Example 1 according to GB / T 23776-2018 standard.

[0079] Table 2

[0080] Group Appearance (points) Soup color (points) Aroma (points) Taste (points) Leaf bottom (points) Example 1 8.85 7.55 5.58 5.68 7.52 Example 2 7.68 7.25 5.12 6.20 7.89 Example 3 8.02 7.64 4.89 5.95 8.21 Example 4 8.35 7.01 5.05 6.01 7.55 Example 5 8.56 7.35 5.21 6.08 7.95 Comparative Example 1 6.23 5.14 4.22 3.56 3.25

[0081] It can be seen from Table 2 that the scores of Examples 1 to 5 are higher than that of Comparative Example 1, which indicates that the green teas of Examples 1 to 5 have better advantages in appearance and tea soup.

[0082] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new green production process for fresh tea, characterized in that: The steps include: S1. Tea picking: Pick the buds that have not yet unfolded their leaves around the Qingming Festival, or pick the high-quality buds of tea with one bud and one leaf just unfolding, complete leaf shape, and full and firm buds after the Qingming Festival and before the Grain Rain Festival. When picking, you must use your fingers to lift and pick, and you cannot pinch and pick with your fingernails; S2, spreading: spreading the picked fresh leaves at 20-30°C for 10-20h; S3, greening: soak the spread fresh leaves in a greening liquid at a temperature of 30-35°C for 10-15 minutes, and use microwave treatment at the same time; S4, dehydration: taking the fresh leaves after greening and performing centrifugal dehydration; S5, strong light irradiation: the dehydrated fresh leaves are spread flat in a pulse strong light treatment room, 2 to 5 cm away from the light source, and subjected to pulse strong light flash treatment; S6, rolling: the treated fresh leaves are put into a rolling machine and rolled for 10 to 30 minutes; S7, freeze drying: put the twisted fresh leaves into the freezing chamber of the freeze dryer and freeze them. After freezing, enter the negative pressure heating drying stage. The moisture content is maintained at 5-7%, and the drying is completed. S8. Packaging: The dried finished tea is directly packaged under negative pressure (vacuum) or nitrogen-filled.

2. A new type of green production process for fresh tea according to claim 1, characterized in that: The preparation method of the greening liquid in step S3 is as follows: soak basalt, medical stone and hematite in pure water for 30 to 60 minutes, use microwave-assisted soaking with a power of 600 to 800 W, filter the filtrate after soaking to obtain the greening liquid; the mass ratio of basalt, medical stone and hematite is 1:0.6 to 0.8:0.2 to 0.

5.

3. The novel green production process of fresh tea according to claim 1 is characterized by: The centrifugal speed in step S4 is 800-1200 r / min.

4. The novel green production process of fresh tea according to claim 1 is characterized by: In step S5, the light intensity is 0.8-0.98 J / cm, and the number of flashes is 120-200 times.

5. The novel green production process of fresh tea according to claim 1 is characterized by: In step S7, the freezing temperature is -20 to -50°C, and the negative pressure heating and drying stage is 10 to 30Pa in the first stage and 20 to 60Pa in the second stage.

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