Baking process of fragrant tea leaves
By employing a process involving supercritical CO2 extraction, activated carbon pretreatment, fermentation with compound enzymatic hydrolysate, and mixed roasting with grapefruit peel, the problems of insufficient flavor and aroma in existing roasting techniques have been solved, thus improving the quality of tea.
Patent Information
- Application Number
- CN202610011337.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-06
- Publication Date
- 2026-02-17
AI Technical Summary
Existing roasting techniques struggle to remove unwanted flavors from tea leaves while preserving their fresh aroma, and the tea's flavor is not rich enough, thus limiting the improvement of tea quality.
The process employs supercritical CO2 extraction combined with activated carbon pretreatment, fermentation with compound enzymatic hydrolysate, and mixed roasting with grapefruit peel. This includes activated carbon pretreatment, supercritical CO2 extraction, fermentation with compound enzymatic hydrolysate, and mixed roasting with grapefruit peel. Activated carbon removes caffeine, enzymatic hydrolysis promotes aroma formation, and grapefruit peel provides complex aromas.
It effectively removes the bitterness and astringency of tea, enhances the flavor and aroma of tea, forms a mellow tea fragrance, retains the fresh and fruity aroma, and improves the quality of tea.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of tea processing technology, specifically, it relates to a roasting process for fragrant tea leaves. Background Technology
[0002] As the world's largest producer and consumer of tea, China's tea industry is showing a steady and positive development trend. Currently, a stable, large-scale production and sales system has been established domestically, and cross-industry application demands continue to expand. To meet the market's pursuit of diversified and high-quality tea products, improving tea quality from the source of production has become a core bottleneck that urgently needs to be overcome in the tea industry. The shaping of tea quality depends on the synergistic effect of tea variety, growing environment, and processing technology. Among these, roasting, as a key link in determining the aroma style and taste transformation of tea, has crucial application value. However, existing mainstream roasting techniques have significant limitations: traditional full-fire roasting, while giving the tea soup a mellow feel, easily masks the original fresh, floral, and fruity aromas of the tea and introduces a roasted taste; simple light-fire roasting, while preserving fresh characteristics, struggles to effectively remove raw, grassy off-flavors and results in insufficient aroma transformation. Current processes largely rely on experience, making it difficult to achieve a stable balance between "removing off-flavors and optimizing taste" and "preserving the fresh aroma of the variety," thus hindering the improvement of tea quality. Summary of the Invention
[0003] The purpose of this invention is to provide a roasting process for fragrant tea, which solves the problems of insufficient tea flavor and incomplete aroma transformation in the existing technology.
[0004] The objective of this invention can be achieved through the following technical solutions: A roasting process for fragrant tea leaves, the roasting process comprising the following steps: S1. Take fresh tea leaves and pretreated activated carbon, mix them, and use supercritical CO2 extraction to obtain pretreated leaves for later use; pretreat fresh grapefruit to obtain grapefruit peel for later use. S2. Spread the pre-treated leaves on a bamboo sieve, place them outdoors to sun-dry, and then move them indoors to dry in a controlled temperature and humidity environment to obtain dried green leaves. S3. Take the dried green leaves and put them into a bamboo shaking machine for shaking to obtain the shaken green leaves; S4. Take the shaken green leaves, spray them evenly with the compound enzyme hydrolysate, and ferment them to obtain fermented leaves; S5. Blanch the fermented leaves to obtain blanched leaves; S6. Put the blanched leaves into a rolling machine and roll them to obtain rolled leaves; S7. Dry the rolled leaves, then spread them out to cool to obtain the initial roasted tea. S8. After removing the tea stems and yellow leaves from the initial roasting of the raw tea, mix it with grapefruit peel and roast it to obtain fragrant tea leaves.
[0005] As a preferred technical solution of the present invention, step S1 specifically includes: S101. Soak activated carbon in ethanol solution A, wash with water until no alcohol odor remains, then soak in potassium hydroxide solution B, wash with water until pH is neutral, then soak in hydrogen chloride solution C, wash with water until pH is neutral, and dry to obtain pretreated activated carbon for later use; take fresh tea leaves and mix with pretreated activated carbon to obtain a mixture, put the mixture into an extraction autoclave, extract with supercritical CO2 to separate the tea leaves, and obtain pretreated leaves; S102. Take a fresh pomelo, remove the pulp and white pith, wash it and let it air dry naturally to obtain the pomelo peel, and set it aside.
[0006] Further, in step S101, the activated carbon has a particle size of 3-5 mm; the ethanol solution has a mass concentration of 70%; the soaking time A is 24 h; the molar concentrations of the potassium hydroxide solution and the hydrogen chloride solution are both 0.1 mol / L; the soaking times B and C are both 12 h; the drying is performed until the moisture content is 2-3%; and the supercritical CO2 extraction temperature is 60-65℃, the pressure is 25-26 MPa, and the time is 1-2 h.
[0007] Furthermore, in step S101, the amount of ethanol solution, potassium hydroxide solution, and hydrogen chloride solution added is 1.5-2 times the mass of activated carbon; the mass ratio of fresh tea leaves to pretreated activated carbon is 9-11:1-2.
[0008] Furthermore, the natural air drying in step S102 refers to air drying until the moisture content is 6-8%.
[0009] As a preferred embodiment of the present invention, in step S2, the spreading thickness is 1-2 cm, the sun-drying time is 1-1.5 h, the temperature for temperature control is 24-30 °C, the relative humidity for humidity control is 50%-60%, and the drying time is 2-4 h.
[0010] As a preferred technical solution of the present invention, step S3 specifically includes: Take the dried green leaves and put them into a bamboo shaking machine. Shake them and place them on a bamboo sieve to cool. Repeat the shaking process 8-10 times.
[0011] Furthermore, the time for each rotation and shaking is 15-20 minutes, the spreading thickness is 4-6 cm, and the cooling is to cool to room temperature.
[0012] As a preferred embodiment of the present invention, the concentration of the compound enzyme solution in step S4 is 0.6-0.8 g / L, and it is prepared by mixing the compound enzyme and deionized water; the spraying is 6-10 mL per kilogram of shaken green leaves.
[0013] Furthermore, the complex enzyme comprises cellulase, catalase, and lipoxygenase in a mass ratio of 2-3:1-2:1.
[0014] Furthermore, the fermentation temperature is 35-45℃, the relative humidity is 60%-70%, and the time is 3-5 hours.
[0015] As a preferred technical solution of the present invention, the blanching temperature in step S5 is 180-200℃ and the time is 5-10min.
[0016] As a preferred embodiment of the present invention, the kneading temperature in step S6 is 20-30℃, the kneading time is 20-30min, and the kneading speed is 10-20rpm.
[0017] As a preferred technical solution of the present invention, the drying in step S7 is to dry to 60% dryness; the time for initial baking and cooling is 1-2 hours, and the cooling thickness is 2-6 cm.
[0018] As a preferred technical solution of the present invention, the mass ratio of the initial roasted tea leaves and grapefruit peel to the tea stems and yellow leaves picked out in step S8 is 8-10:2-3; the roasting temperature is 100-120℃, the roasting time is 12-16h, and the leaves are turned over once every 45min during the roasting period.
[0019] The beneficial effects of this invention are: (1) This invention uses supercritical CO2 extraction and activated carbon adsorption to effectively remove caffeine from tea. Soaking activated carbon in ethanol solution can dissolve and remove organic impurities adsorbed on the surface of activated carbon, open up the pore structure, and alternate acid and alkali soaking can further wash away inorganic impurities, activate adsorption sites, enhance adsorption capacity, and improve the removal efficiency of caffeine from tea. Caffeine, as the main flavor substance of bitterness in tea, can significantly reduce the bitterness of tea.
[0020] (2) This invention uses a combination of cellulase, catalase and lipoxygenase for fermentation. Cellulase can degrade cellulose and hemicellulose in plant cell walls, destroy cell wall structure, and promote the dissolution of polyphenols, amino acids, fatty acids and other substances in tea cells, providing substrates for subsequent enzymatic reactions. Catalase participates in the enzymatic oxidation and polymerization of phenolic substances in tea fermentation, and can catalyze theaflavin to further form thearubigin, making the oxidation reaction more thorough. It has a synergistic effect with polyphenol oxidase contained in tea, and at the same time reduces the excessive production of theabrownin, which can prevent the tea soup from becoming dark. Lipoxygenase catalyzes the oxidation of polyunsaturated fatty acids in tea and further decomposes them into volatile flavor substances, promoting the formation of tea aroma substances. The synergistic effect of the three enzymes can significantly improve the taste and aroma of tea.
[0021] (3) When the grapefruit peel is mixed with tea leaves for roasting, the amino acids and sugars in the tea leaves and grapefruit peel provide conditions for Maillard reaction and caramelization reaction. These reactions will produce complex aromas such as roasting aroma and fruit aroma. At the same time, grapefruit peel contains volatile limonene and naringin, and the complex aroma is adsorbed inside and outside the tea leaves, giving it a unique fragrance.
[0022] (4) The present invention kills the fermented leaves, which can prevent the tea leaves from fermenting, remove the grassy taste, evaporate the moisture, and improve the aroma. At the same time, it can also make the tea leaves mature, soft, and easy to knead. Detailed Implementation
[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0024] The cellulase (400 U / mg), catalog number S10042, used in the embodiments, comparative examples, and test examples of this invention was purchased from Shanghai Yuanye Biotechnology Co., Ltd.; the lipoxygenase (50000 U / mg), catalog number S10198, was purchased from Shanghai Yuanye Biotechnology Co., Ltd.; and the catalase (2000 U / mg), catalog number AS10037, was purchased from Shanghai Lianshuo Biotechnology Co., Ltd. Further details will not be repeated hereafter.
[0025] Example 1 A roasting process for fragrant tea leaves, the roasting process comprising the following steps: S1. Mix fresh tea leaves with pretreated activated carbon and extract using supercritical CO2 to obtain pretreated leaves for later use; pretreat fresh grapefruit to obtain grapefruit peel for later use; specifically including the following steps: S101. Activated carbon with a particle size of 3 mm is soaked in a 70% ethanol solution for 24 hours, washed with water until no alcohol odor is detected, then soaked in a 0.1 mol / L potassium hydroxide solution for 12 hours, washed with water until the pH is neutral, then soaked in a 0.1 mol / L hydrogen chloride solution for 12 hours, washed with water until the pH is neutral, and dried to a moisture content of 3% to obtain pretreated activated carbon for later use; fresh tea leaves and pretreated activated carbon are mixed to obtain a mixture, which is then placed in an extraction autoclave and extracted with supercritical CO2 at a temperature of 60℃ and a pressure of 26 MPa for 1.5 hours to separate the tea leaves and obtain pretreated leaves; The amounts of ethanol solution, potassium hydroxide solution, and hydrogen chloride solution added are all twice the mass of activated carbon. The mass ratio of the fresh tea leaves to the pretreated activated carbon is 9:1.5; S102. Take a fresh pomelo, remove the pulp and white pith, wash it and air dry it naturally until the moisture content is 7% to obtain pomelo peel for later use. S2. Spread the pretreated leaves on a bamboo sieve with a thickness of 1cm, place them outdoors to sun-dry for 1.5 hours, and then move them indoors at a temperature of 27℃ and a humidity of 60% for 3 hours to obtain dried green leaves. S3. Take the dried green leaves and put them into a bamboo shaking machine. Shake for 20 minutes. Place them on a bamboo sieve and spread them out to cool to room temperature with a thickness of 4cm. Repeat the shaking 9 times to obtain the shaken green leaves. S4. Take the shaken green leaves and spray them evenly with the compound enzyme hydrolysate. Ferment at 35℃ and 70% relative humidity for 4 hours to obtain fermented leaves. The concentration of the compound enzyme solution is 0.7 g / L, and it is prepared by mixing the compound enzyme and deionized water; the spraying is 10 mL per kilogram of shaken green leaves; The complex enzyme comprises cellulase, catalase, and lipoxygenase in a mass ratio of 2.5:2:1. S5. Place the fermented leaves in a pan and fix them at 180℃ for 7.5 minutes to obtain the fixed leaves. S6. Put the blanched leaves into a rolling machine and roll them at 30℃ and 10 rpm for 25 minutes to obtain rolled leaves. S7. Dry the rolled leaves to 60% dryness, spread them out to cool for 1 hour in a 2cm thickness to obtain the initial roasted tea. S8. After removing the tea stems and yellow leaves from the initial roasting of the raw tea, mix it with grapefruit peel and roast for 14 hours, turning it every 45 minutes during roasting to obtain fragrant tea leaves. The mass ratio of the initial roasted tea leaves (without tea stems and yellow leaves) to the grapefruit peel is 4:1.
[0026] Example 2 A roasting process for fragrant tea leaves, the roasting process comprising the following steps: S1. Mix fresh tea leaves with pretreated activated carbon and extract using supercritical CO2 to obtain pretreated leaves for later use; pretreat fresh grapefruit to obtain grapefruit peel for later use; specifically including the following steps: S101. Activated carbon with a particle size of 5 mm is soaked in a 70% ethanol solution for 24 hours, washed with water until no alcohol odor is detected, then soaked in a 0.1 mol / L potassium hydroxide solution for 12 hours, washed with water until the pH is neutral, then soaked in a 0.1 mol / L hydrogen chloride solution for 12 hours, washed with water until the pH is neutral, and dried to a moisture content of 2.5% to obtain pretreated activated carbon for later use. Fresh tea leaves and pretreated activated carbon are mixed to obtain a mixture. The mixture is placed in an extraction autoclave and extracted with supercritical CO2 at a temperature of 62.5℃ and a pressure of 25 MPa for 1 hour to separate the tea leaves and obtain pretreated leaves. The amounts of ethanol solution, potassium hydroxide solution, and hydrogen chloride solution added are all 1.5 times the mass of activated carbon. The mass ratio of the fresh tea leaves to the pretreated activated carbon is 11:2; S102. Take a fresh pomelo, remove the pulp and white pith, wash it and air dry it naturally until the moisture content is 8% to obtain pomelo peel for later use. S2. Spread the pretreated leaves on a bamboo sieve with a thickness of 2cm, place them outdoors in the sun for 1.25 hours, and then move them indoors at a temperature of 24℃ and a relative humidity of 55% for 2 hours to obtain dried green leaves. S3. Take the dried green leaves and put them into a bamboo shaking machine. Shake for 17.5 minutes. Place them on a bamboo sieve and spread them out to cool to room temperature. Repeat the shaking process 8 times. S4. Take the shaken green leaves and spray them evenly with the compound enzyme hydrolysate. Ferment at 45℃ and 65% relative humidity for 3 hours to obtain fermented leaves. The concentration of the compound enzyme solution is 0.8 g / L, and it is prepared by mixing the compound enzyme and deionized water; the spraying is 6 mL per kilogram of sun-dried green leaves. The complex enzyme comprises cellulase, catalase, and lipoxygenase in a mass ratio of 3:1.5:1. S5. Place the fermented leaves in a wok and fix them at 200℃ for 10 minutes to obtain the fixed leaves. S6. Put the blanched leaves into a rolling machine and roll them at 25°C and 15 rpm for 30 minutes to obtain rolled leaves. S7. Dry the rolled leaves to 60% dryness, spread them out to cool to a thickness of 4cm, and roast for 1.5 hours to obtain the initial roasted tea. S8. After removing the tea stems and yellow leaves from the initial roasting of the raw tea, mix it with grapefruit peel and roast for 16 hours, turning it every 45 minutes during roasting to obtain fragrant tea leaves. The mass ratio of the initial roasted tea leaves (after removing the tea stems and yellow leaves) to the grapefruit peel is 9:2.
[0027] Example 3 A roasting process for fragrant tea leaves, the roasting process comprising the following steps: S1. Mix fresh tea leaves with pretreated activated carbon and extract using supercritical CO2 to obtain pretreated leaves for later use; pretreat fresh grapefruit to obtain grapefruit peel for later use; specifically including the following steps: S101. Activated carbon with a particle size of 4 mm is soaked in a 70% ethanol solution for 24 hours, washed with water until no alcohol odor is detected, then soaked in a 0.1 mol / L potassium hydroxide solution for 12 hours, washed with water until the pH is neutral, then soaked in a 0.1 mol / L hydrogen chloride solution for 12 hours, washed with water until the pH is neutral, and dried to a moisture content of 2% to obtain pretreated activated carbon for later use; fresh tea leaves and pretreated activated carbon are mixed to obtain a mixture, which is then placed in an extraction autoclave and extracted with supercritical CO2 at a temperature of 65℃ and a pressure of 25.5 MPa for 2 hours to separate the tea leaves and obtain pretreated leaves; The amounts of ethanol solution, potassium hydroxide solution, and hydrogen chloride solution added are all 1.75 times the mass of activated carbon. The mass ratio of the fresh tea leaves to the pretreated activated carbon is 10:1; S102. Take a fresh pomelo, remove the pulp and white pith, wash it and air dry it naturally until the moisture content is 6% to obtain pomelo peel for later use. S2. Spread the pretreated leaves on a bamboo sieve with a thickness of 1.5cm, place them outdoors in the sun for 1 hour, and then move them indoors at a temperature of 30℃ and a relative humidity of 50% for 4 hours to obtain dried green leaves. S3. Take the dried green leaves and put them into a bamboo shaking machine. Shake for 15 minutes, then place them on a bamboo sieve and spread them out to cool to room temperature. Repeat the shaking 10 times. S4. Take the shaken green leaves and spray them evenly with the compound enzyme hydrolysate. Ferment at 40℃ and 60% relative humidity for 5 hours to obtain fermented leaves. The concentration of the compound enzyme solution is 0.6 g / L, and it is prepared by mixing the compound enzyme and deionized water; the spraying is 8 mL per kilogram of sun-dried green leaves. The complex enzyme comprises cellulase, catalase and lipoxygenase in a mass ratio of 2:1:1. S5. Place the fermented leaves in a wok and fix them at 190℃ for 5 minutes to obtain the fixed leaves. S6. Put the blanched leaves into a rolling machine and roll them at 20℃ and 20 rpm for 20 minutes to obtain rolled leaves. S7. Dry the rolled leaves to 60% dryness, spread them out to cool for 2 hours to obtain the initial roasted tea. S8. After removing the tea stems and yellow leaves from the initial roasting of the raw tea, mix it with grapefruit peel and roast for 12 hours, turning it every 45 minutes during roasting to obtain fragrant tea leaves. The mass ratio of the initial roasted tea leaves (without tea stems and yellow leaves) to the grapefruit peel is 8:3.
[0028] Comparative Example 1 Compared with Example 1, the difference is that in Comparative Example 1, the activated carbon is not soaked in ethanol solution in step S101, while the other operation steps and parameters remain unchanged.
[0029] Comparative Example 2 Compared with Example 1, the difference is that in Comparative Example 2, potassium hydroxide solution is not used to soak activated carbon in step S101, while the other operation steps and parameters remain unchanged.
[0030] Comparative Example 3 Compared with Example 1, the difference is that in Comparative Example 3, the activated carbon is not soaked in hydrogen chloride solution in step S101, while the other operation steps and parameters remain unchanged.
[0031] Comparative Example 4 Compared with Example 1, the difference is that supercritical CO2 is not used for extraction in step S101 of Comparative Example 4, while the other operation steps and parameters remain unchanged.
[0032] Comparative Example 5 Compared with Example 1, the difference is that in Comparative Example 5, step S101 does not involve pretreatment of the activated carbon, i.e.: S101. Take fresh tea leaves and activated carbon and mix them to obtain a mixture. Put the mixture into an extraction autoclave and extract it with supercritical CO2 to separate the tea leaves and obtain pretreated leaves. All other operating steps and parameters remain unchanged.
[0033] Comparative Example 6 Compared with Example 1, the difference is that no cellulase was added to the complex enzymatic hydrolysate of Comparative Example 6, and the missing weight was made up with catalase and lipoxygenase in a mass ratio of 2:1. All other operation steps and parameters remained unchanged.
[0034] Comparative Example 7 Compared with Example 1, the difference is that catalase was not added to the complex enzymatic hydrolysate of Comparative Example 7, and the missing weight was made up of cellulase and lipoxygenase in a mass ratio of 2.5:1. All other operation steps and parameters remained unchanged.
[0035] Comparative Example 8 Compared with Example 1, the difference is that no lipoxygenase was added to the complex enzymatic hydrolysate of Comparative Example 8, and the missing weight was made up with cellulase and catalase in a mass ratio of 2.5:2. All other operation steps and parameters remained unchanged.
[0036] Comparative Example 9 Compared with Example 1, the difference is that the compound enzymatic hydrolysate was not sprayed in step S4 of Comparative Example 9, while the other operation steps and parameters remained unchanged.
[0037] Comparative Example 10 Compared with Example 1, the difference is that grapefruit peel is not added in step S8 of Comparative Example 10 during baking, while the other operation steps and parameters remain unchanged.
[0038] Test Example 1 According to the standard GB / T 8312-2013 "Determination of Caffeine in Tea", the caffeine content of tea prepared in Examples 1-3 and Comparative Examples 1-5 and untreated fresh tea were determined. The data of untreated fresh tea were used as a blank group to obtain the removal rate. The results are shown in Table 1.
[0039] Table 1 As can be seen from Table 1, the tea prepared under the roasting process of the present invention can effectively remove caffeine. Specifically, as can be seen from Comparative Examples 1-5, the present invention uses supercritical CO2 extraction and activated carbon adsorption to effectively remove caffeine from tea.
[0040] Test Example 2 Referring to the standard GB / T 23776-2018 "Sensory Evaluation Methods for Tea", the teas prepared in Examples 1-3 and Comparative Examples 1-9 were evaluated by professional tea evaluators based on three evaluation factors: liquor color, aroma, and taste; the results are shown in Table 2.
[0041] Table 2 As can be seen from Table 2, the roasting process of the present invention can significantly improve the flavor and aroma of tea. The prepared tea has a rich aroma, a complex and lasting fragrance, a mellow taste, a rich mouthfeel, a distinct aftertaste, and an orange-red, clear and bright tea soup.
[0042] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0043] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.
Claims
1. A roasting process for fragrant tea leaves, characterized in that, The baking process includes the following steps: S1. Take fresh tea leaves and pretreated activated carbon, mix them, and use supercritical CO2 extraction to obtain pretreated leaves for later use; pretreat fresh grapefruit to obtain grapefruit peel for later use. S2. Spread the pre-treated leaves on a bamboo sieve, place them outdoors to sun-dry, and then move them indoors to dry in a controlled temperature and humidity environment to obtain dried green leaves. S3. Take the dried green leaves and put them into a bamboo shaking machine for shaking to obtain the shaken green leaves; S4. Take the shaken green leaves, spray them evenly with the compound enzyme hydrolysate, and ferment them to obtain fermented leaves; S5. Blanch the fermented leaves to obtain blanched leaves; S6. Put the blanched leaves into a rolling machine and roll them to obtain rolled leaves; S7. Dry the rolled leaves, then spread them out to cool to obtain the initial roasted tea. S8. After removing the tea stems and yellow leaves from the initial roasting of the raw tea, mix it with grapefruit peel and roast it to obtain fragrant tea leaves.
2. The roasting process for a lightly roasted tea according to claim 1, characterized in that, Step S1 specifically includes: S101. Soak activated carbon in ethanol solution A, wash with water until no alcohol odor remains, then soak in potassium hydroxide solution B, wash with water until pH is neutral, then soak in hydrogen chloride solution C, wash with water until pH is neutral, and dry to obtain pretreated activated carbon for later use; take fresh tea leaves and mix with pretreated activated carbon to obtain a mixture, put the mixture into an extraction autoclave, extract with supercritical CO2 to separate the tea leaves, and obtain pretreated leaves; S102. Take a fresh pomelo, remove the pulp and white pith, wash it and let it air dry naturally to obtain the pomelo peel, and set it aside.
3. The roasting process for a fragrant tea according to claim 2, characterized in that, In step S101, the activated carbon has a particle size of 3-5 mm; the ethanol solution has a mass concentration of 70%; the soaking time A is 24 h; the molar concentrations of the potassium hydroxide solution and hydrogen chloride solution are both 0.1 mol / L; the soaking times B and C are both 12 h; the drying is carried out until the moisture content is 2-3%; the supercritical CO2 extraction temperature is 60-65℃, the pressure is 25-26 MPa, and the time is 1-2 h. The amounts of ethanol solution, potassium hydroxide solution, and hydrogen chloride solution added are all 1.5-2 times the mass of activated carbon; the mass ratio of fresh tea leaves to pretreated activated carbon is 9-11:1-2. The natural air drying in step S102 refers to natural air drying until the moisture content is 6-8%.
4. The roasting process for a lightly roasted tea according to claim 1, characterized in that, In step S2, the spreading thickness is 1-2 cm, the sun-drying time is 1-1.5 h, the temperature is 24-30℃, the relative humidity is 50%-60%, and the drying time is 2-4 h.
5. The roasting process for a lightly roasted tea according to claim 1, characterized in that, Step S3 specifically includes: taking the dried green leaves and putting them into a bamboo shaking machine, rotating and shaking them, placing them on a bamboo sieve to cool, and repeating the shaking process 8-10 times. The time for each rotation and shaking is 15-20 minutes, the thickness of the spread layer is 4-6 cm, and the cooling is to cool to room temperature.
6. The roasting process for a fragrant tea according to claim 1, characterized in that, The concentration of the compound enzyme solution in step S4 is 0.6-0.8 g / L, and it is prepared by mixing the compound enzyme and deionized water; the spraying is 6-10 mL per kilogram of sun-dried green leaves. The complex enzyme comprises cellulase, catalase and lipoxygenase in a mass ratio of 2-3:1-2:1; The fermentation temperature in step S4 is 35-45℃, the relative humidity is 60%-70%, and the time is 3-5 hours.
7. The roasting process for a lightly roasted tea according to claim 1, characterized in that, The blanching temperature in step S5 is 180-200℃, and the time is 5-10 minutes.
8. The roasting process for a light-aroma tea according to claim 1, characterized in that, The kneading temperature in step S6 is 20-30℃, the kneading time is 20-30 min, and the kneading speed is 10-20 rpm.
9. The roasting process for a lightly roasted tea according to claim 1, characterized in that, The drying process described in step S7 involves drying the food to 60% dryness; the initial baking and cooling time is 1-2 hours, and the cooling thickness is 2-6 cm.
10. The roasting process for a lightly roasted tea according to claim 1, characterized in that, In step S8, the mass ratio of the initial roasted tea leaves (after removing tea stems and yellow leaves) to the grapefruit peel is 8-10:2-3; the roasting temperature is 100-120℃, the roasting time is 12-16 hours, and the tea is turned over every 45 minutes during the roasting process.