Processing method of raw material tea with special flavor

Abstract

The invention relates to the field of tea production, and discloses a special flavor raw material tea processing method, which comprises the following steps: tea garden management, arginine foliage dressing, and red, blue and yellow multi-light-quality intermittent light stress on leaf surfaces; fresh leaves are picked, and tea tree tender shoots are picked after stress treatment and self-adaption before picking; the white tea processing comprises the following steps: carrying out red, blue and yellow dark and cold and hot air intermittent combination and atomization exogenous addition type first withering on fresh leaves, carrying out multifunctional enzyme activity ventilation addition and cold and hot air intermittent variable air combination secondary withering on the leaves withered for the first time, carrying out high-pressure or ultrasonic cell disruption on the leaves withered for the second time, and carrying out drying and drying. And piling and absorbing fragrance of the cell-broken leaves through warm and wet air containing orchid essential oil and plant-extracted amino acid, and drying the piled and absorbed leaves through combination of hot-air quick drying and far-infrared supplementary drying to obtain the flower-fragrance fresh and sweet white tea. The flower fragrance fresh and sweet white tea is prepared from the comprehensive direction of tea garden management, fresh leaf picking and tea leaf processing, and a high-quality white tea product can be stably obtained.

Description

[0001] This application is a divisional application of application number 202410497664.7, application date April 24, 2024, entitled "A method for preparing a floral-sweet white tea". Technical Field

[0002] This invention relates to the field of tea production technology, and in particular to a method for processing raw tea with distinctive flavor. Background Technology

[0003] White tea is one of the six major tea categories in my country. It possesses distinct flavor characteristics and health benefits compared to other teas such as black and green tea, making it highly popular among consumers. White tea is mainly produced in Fujian province, but production also extends to Yunnan and Zhejiang provinces. In recent years, white tea production has grown rapidly, and its market coverage has continued to expand.

[0004] Traditional white tea is generally processed through two steps: withering and drying. Withering is a crucial step in the formation of white tea's quality. During the prolonged withering process, fresh tea leaves undergo slow enzymatic transformation reactions involving polyphenol oxidases, glycoside hydrolases, and proteolytic enzymes, promoting the formation of aroma and flavor compounds. Subsequently, a long-term, low-temperature drying process removes moisture, fixes color, and enhances aroma and flavor, resulting in white tea's characteristic fragrant aroma, fresh taste, and bright liquor. However, traditional Chinese white tea processing techniques suffer from low efficiency and inconsistent quality. Non-standard processing methods result in weak and short-lasting aromas, a bland and slightly astringent taste, and a dull color. Furthermore, the overall quality and flavor of existing white tea are relatively uniform, exhibiting significant homogenization, which fails to meet consumers' diverse needs for tea products, hindering the expansion of the white tea market.

[0005] To address the aforementioned issues and meet the diversified demands of the market, scholars have undertaken various efforts. For example, Chinese patent application CN2017106529078 describes a highly aromatic white tea made from high-aroma varieties suitable for oolong tea processing using white tea processing techniques; Chinese patent application CN2021104942793 integrates the shaking and fermentation processes of oolong tea to enhance the longevity of the floral aroma in white tea; Chinese patent application CN2020102868086 integrates the rolling and light fermentation processes of black tea to enhance the richness of the flavor in white tea; and Chinese patent application CN2022109863792 combines cold rolling and low-temperature vacuum drying processes to maintain the vibrant color and fresh, mellow flavor of white tea. However, these attempts have many problems. For example, the processing of high-aroma varieties cannot be widely promoted. The shaking process is insufficient in terms of the accumulation of aroma substances and is cumbersome. The addition of kneading and fermentation has changed the original color, aroma and flavor characteristics of white tea. Cold kneading and low-temperature vacuum drying are only used to improve the color, resulting in low aroma and a bitter taste. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a method for processing specialty flavored raw tea, which can reliably produce high-quality white tea products.

[0007] The present invention solves the above-mentioned technical problems through the following technical means:

[0008] A method for processing a specialty flavored raw tea, comprising the following steps:

[0009] S1. First withering: Fresh leaves are withered by a combination of red, blue and yellow light-free and cold and hot air intermittently combined with atomized external source addition to obtain the first withered leaves;

[0010] S2, Secondary withering: The leaves that have been withered for the first time are withered by adding multifunctional enzyme-activated ventilation and a combination of intermittent hot and cold air to obtain leaves withered for the second time.

[0011] S3. Cell disruption: Cell disruption of secondary withered leaves is achieved by high pressure or ultrasound to obtain cell-disrupted leaves.

[0012] S4. Fragrance extraction: The broken leaves are fumigated with warm, humid air containing floral essential oils and plant-extracted amino acids to obtain fragrance-absorbing leaves.

[0013] S5. Drying: The collected fragrant leaves are dried using a combination of hot air drying and far-infrared drying to obtain a white tea with a fresh and sweet floral aroma.

[0014] Furthermore, the tea garden management for the fresh white tea leaves 15-20 days before harvesting includes fertilization management and pre-harvest light stress treatment. The fertilization management involves spraying the tea tree canopy with foliar fertilizer containing 10-15g / L arginine. The pre-harvest light stress treatment involves suspending light tubes or colored shade cloths and applying intermittent light stress treatments such as red light, blue light, and yellow light. The intermittent treatment involves applying red light for 1.5-2.5 hours, then no light for 0.3-0.7 hours, blue light for 1.5-2.5 hours, then no light for 0.3-0.7 hours, yellow light for 1.5-2.5 hours, then no light for 0.3-0.7 hours to the new shoots of the tea trees in a cyclical intermittent light stress treatment, with a light intensity of 6000-9000 lux, for a total of 3-4 cycles.

[0015] Furthermore, the fresh white tea leaves are harvested from the new shoots and leaves of tea trees that have undergone 10-15 hours of pre-harvest light stress treatment to adapt, and the tenderness is single bud, one bud and one leaf, one bud and two leaves, and one bud and three leaves.

[0016] Furthermore, during the initial withering in step S1, the thickness of the fresh white tea leaves is 2-3 cm, and the humidity is 55-65%.

[0017] Furthermore, in step S1, during the intermittent withering process using a combination of red, blue, and yellow light in the absence of light and hot and cold air, the distance between the light source and the fresh white tea leaves is 25-40 cm, and the light intensity is 6000-12000 lux. During the intermittent withering process using red, blue, and yellow light in the absence of light, a cycle is performed with red light on for 15-25 minutes, blue light on for 25-35 minutes, yellow light on for 25-35 minutes, and then stopped for 5-15 minutes. During the intermittent withering process using hot air, hot air at 23-27℃ is blown for 15-20 minutes at a wind speed of 3-5 m / s, followed by a cycle of 18-2... The treatment cycle consists of blowing cold air at 2℃ for 20-25 minutes at a wind speed of 6-8 m / s, followed by 20-25 minutes without wind. During the atomized external additive withering process, floral essential oils and plant-derived amino acids are dissolved in pure water at a volume ratio of 1:(100-120) and 1:(50-70) to prepare an aroma-enhancing liquid. This liquid is then vaporized using ultrasonic atomization, and the vaporized liquid is blown upwards over the withering leaves. The withering time is 25-30 hours, until the moisture content reaches 40%-45%.

[0018] Furthermore, during the second withering in step S2, the leaf thickness of the first withered leaves is 4-5 cm, the temperature is 25-30℃, and the humidity is 65%-75%.

[0019] Further, the method of adding multifunctional enzyme-activated ventilation and combining intermittent hot and cold air withering in step S2 includes: dissolving exogenous cellulase and lipoxygenase in pure water at volume ratios of 1:(500-550) and 1:(500-550) respectively, vaporizing them by ultrasonic atomization, and blowing the vaporized enzyme liquid over the withering leaves from bottom to top at a wind speed of 2-4 m / s for 1.0-2.0 hours; then adding exogenous proteolytic enzyme and glycoside hydrolytic enzyme at volume ratios of 1:(400-450) and 1:(500-550) respectively. Dissolve the enzyme solution in pure water at a volume ratio of (400-450), vaporize it using ultrasonic atomization, and blow the vaporized enzyme solution over the wilted leaves from bottom to top at a wind speed of 2-4 m / s for 1.0-2.0 hours. Then, use intermittent hot and cold air for wilting: blow with hot air at 26-30℃ for 15-20 minutes at a wind speed of 3-5 m / s, blow with cold air at 21-25℃ for 20-25 minutes at a wind speed of 6-8 m / s, and then no wind for 30-35 minutes. The wilting time is 15-20 hours, until the leaf moisture content is 20%-25%.

[0020] Furthermore, in step S3, the high pressure is 20-30 kPa, and the ultrasonic frequency is 80-100 kHz; during cell disruption, the thickness of the secondary withered leaves is 2-4 cm, and the high pressure or ultrasonic treatment time is 1.0-1.5 min. This technical solution improves the tea infusion rate, facilitates the formation of a fresh and sweet tea flavor, addresses the problem of the existing white tea infusion being too weak, and also benefits the subsequent aroma absorption process during the piling and stacking stage.

[0021] Furthermore, during the collection and inhalation of fragrance in step S4, the cell-broken leaves are placed on a multi-layer shelf, with the thickness of the cell-broken leaves gradually increasing from bottom to top. The leaf thicknesses from bottom to top are 2-3cm, 4-6cm, 8-10cm, and 13-15cm, respectively. The leaves are then inhaled for 6-10 hours by passing warm, humid air containing floral essential oils and plant-extracted amino acids in volume ratios of 1:(80-100) and 1:(30-40), respectively. The temperature of the warm, humid air is 25-30℃, and the humidity is 50-60%.

[0022] Furthermore, during the drying process in step S5, a combination of hot air rapid drying and far-infrared supplementary drying is used. The hot air rapid drying process uses a hot air temperature of 90-100℃, a hot air volume of 10-12 m / s, and a drying time of 3-5 min, resulting in a leaf thickness of 1-2 cm. The leaves are then spread out to cool and rehydrate for 30-40 min, resulting in a leaf thickness of 3-4 cm. The far-infrared supplementary drying process uses a far-infrared temperature of 60-70℃, a leaf thickness of 3-4 cm, and a drying time of 40-60 min, until the moisture content is <7%.

[0023] The floral essential oil used in this invention can be orchid essential oil or other floral essential oils, and can be selected according to different tastes.

[0024] The beneficial effects of this invention are:

[0025] 1. In tea garden management, this invention involves spraying foliar fertilizer containing arginine to increase fresh leaf yield, regulate carbon and nitrogen metabolism in leaves, increase amino acid content in leaves, reduce tea polyphenol content, and increase the content of floral and fruity aroma substances such as β-ionone, phenylethanol, (Z)-jasmone, and linalool in fresh leaves. Pre-harvest light stress, through innovative intermittent regulation of red, blue, yellow, and no light, significantly upregulates the expression of the CsPPO1 gene in leaves, which can promote the metabolism of glycosides, lipids, and fatty acids, and promote the transformation and formation of aroma substances such as alcohols, esters, and aldehydes.

[0026] 2. In the initial withering process, this invention employs a combination of light-free (red, blue, and yellow) and intermittent hot and cold air with atomized external additive withering method. This method removes moisture and grassy odor from the withered leaves while concentrating the aroma-enhancing liquid on the leaf surface. Simultaneously, innovative synergistic regulation of light quality, temperature, and wind speed rapidly activates and enhances the activity of glycosidases, proteases, polysaccharide hydrolases, and lipoxygenases within the leaves. This promotes the degradation of macromolecules such as proteins, cellulose, polysaccharides, glycosides, flavonoids, and lipids, and increases the content of volatile aromatic compounds such as alcohols, ketones, and aldehydes, as well as amino acids, soluble sugars, and simple catechins. This provides the conditions and material basis for the formation of floral aroma and fresh, sweet flavor.

[0027] 3. In the secondary withering process, this invention employs a multifunctional enzyme gradient ventilation addition + intermittent hot and cold air variable withering method. First, cellulase and lipoxygenase hydrolyze cellulose in the cell wall and phospholipids in the cell membrane, increasing the cell wall and cell membrane breakage rate. This facilitates the subsequent entry of proteolytic enzymes and glycoside hydrolases into the cells to carry out quality improvement reactions, while also increasing the tea infusion extraction rate and promoting the hydrolysis of polysaccharides and lipids, which is beneficial for the enrichment of sweet flavor and floral aroma precursors such as soluble sugars and fatty acids. Subsequently, the addition of proteolytic enzymes and glycoside hydrolases promotes the hydrolysis of proteins and glycoside precursors, as well as the accumulation of umami and sweet substances such as amino acids and soluble sugars, and the enrichment of floral and fruity aroma substances such as linalool, geraniol, benzyl alcohol, and phenethyl alcohol.

[0028] 4. The innovative cell disruption step in this invention can break down the cell walls and cell membranes of tea leaves, increasing the extraction rate of tea liquor and facilitating the formation of a fresh and sweet tea liquor flavor, thus solving the problem of the blandness of existing white tea liquor. Combined with the aroma absorption process, orchid essential oil and amino acids are absorbed from bottom to top in a moist and hot manner through the gradient of leaf thickness from bottom to top, which facilitates the uniform and efficient adsorption and adhesion of tea leaves to leaf cells and leaf surface, enhancing the floral and fruity aroma, fresh and sweet taste of tea, and the concentration of tea liquor. At the same time, it provides a rich material basis for the subsequent conversion of drying substances.

[0029] 5. This invention innovatively uses hot air rapid drying + far-infrared supplementary drying technology. This drying technology can avoid the problems of graying color caused by traditional hot air drying and bland aroma caused by long-term low temperature. The hot air rapid drying + far-infrared supplementary drying method quickly stimulates the aroma quality of white tea through high temperature, and promotes the rapid evaporation and dissipation of moisture in the leaves from the inside out through far-infrared drying. The white tea produced has a rich floral aroma, sweet taste, and significantly improved greenness of tea soup and appearance, significantly improving the aroma, taste and color quality of white tea.

[0030] 6. The process technology of this invention is highly innovative and easy to operate, and can stably obtain high-quality floral and sweet white tea. Attached Figure Description

[0031] Figure 1This is a process flow diagram of a special flavored raw material tea processing method according to the present invention;

[0032] Figure 2 The concentration of aroma categories in floral-sweet white tea samples was determined by different processing techniques used in Examples 1-3 and the comparative examples. Figure 1 :

[0033] Figure 3 The concentration of aroma categories in floral-sweet white tea samples was determined by different processing techniques used in Examples 1-3 and the comparative examples. Figure 2 . Detailed Implementation

[0034] The present invention will now be described in detail with reference to the embodiments and accompanying drawings:

[0035] Example 1

[0036] This embodiment describes a method for processing specialty flavored raw tea ingredients.

[0037] In this embodiment, the fresh leaves used to prepare the floral-sweet white tea were harvested from the new shoots of tea trees that had undergone a 10-hour pre-harvest light stress treatment to adapt. The tenderness of the shoots included approximately half one bud and one leaf and half one bud and two leaves. The tea garden management for the 15 days prior to harvesting included fertilization and pre-harvest light stress treatment. Fertilization involved spraying the tea tree canopy with a foliar fertilizer containing 10 g / L arginine. The pre-harvest light stress treatment involved suspending light tubes or colored shading cloths and applying intermittent light stress treatments of red, blue, and yellow light. The intermittent treatment consisted of 1.5 hours of red light followed by 0.3 hours of no light, 1.5 hours of blue light followed by 0.3 hours of no light, and 1.5 hours of yellow light followed by 0.3 hours of no light, with a light intensity of 6000 lux, for a total of three cycles.

[0038] The preparation steps for fresh white tea leaves with a floral and sweet aroma are as follows:

[0039] S1. Initial withering: Fresh white tea leaves are withered using a combination of intermittent withering with red, blue, and yellow light in the dark, plus hot and cold air, and with external atomization. The initial withering of fresh white tea leaves is done in a 2cm thick pile with a humidity of 55%. In this embodiment, the withering is carried out in a withering trough. Specifically: ① Intermittent withering with red, blue, and yellow light in the dark: The light source is 25cm away from the fresh leaves, and the light intensity is 6000 lux. During intermittent treatment, red light is on for 15 minutes, blue light for 25 minutes, yellow light for 25 minutes, followed by a 5-minute pause, constituting one cycle. ② Intermittent hot and cold air variable ventilation. Withering: 15 minutes of hot air blowing at 23℃ with a wind speed of 3m / s, 20 minutes of cold air blowing at 18℃ with a wind speed of 6m / s, and 20 minutes of no wind; ③ Atomized external additive withering: orchid essential oil and plant-extracted amino acids are dissolved in pure water at volume ratios of 1:100 and 1:50 to prepare flavor-enhancing liquid. The flavor-enhancing liquid is vaporized by ultrasonic atomization. The vaporized flavor-enhancing liquid is blown from bottom to top over the withered leaves. The withering time is 25 hours until the moisture content is 40%.

[0040] S2. Secondary withering: This process employs a multi-functional enzyme-activated ventilation system combined with intermittent hot and cold air withering. It is carried out in a withering trough or withering machine. The fresh white tea leaves are piled to a thickness of 4cm, at a temperature of 25℃ and humidity of 65%. Specifically: ① Exogenous cellulase and lipoxygenase are dissolved in pure water at a volume ratio of 1:500 and 1:500 respectively. The dissolved enzymes are then vaporized using ultrasonic atomization. The vaporized enzyme liquid is blown upwards over the withered leaves at a wind speed of 2m / s for 1.0 hour. ② Then... Exogenous proteolytic enzymes and glycoside hydrolases were dissolved in pure water at volume ratios of 1:400 and 1:400, respectively. The solutions were then vaporized by ultrasonic atomization. The vaporized enzyme solution was blown over the wilted leaves from bottom to top at a wind speed of 2 m / s for 1.0 h. Subsequently, intermittent hot and cold air were used for wilting: 26℃ hot air for 15 min at a wind speed of 3 m / s, 21℃ cold air for 20 min at a wind speed of 6 m / s, and no wind for 30 min. The wilting time was 15 h, and the leaves were wilted until the moisture content reached 20%.

[0041] S3. Cell disruption: The tea leaves are disrupted using a high-pressure method at 20 kPa, with a leaf thickness of 2 cm and a duration of 1.0 min.

[0042] S4. Fragrance inhalation: Place multi-layered shelves in the facility space, with shelves spaced 10cm apart. The tea leaves are gradually thickened from bottom to top (leaf thickness 2cm, 4cm, 8cm, 13cm). The tea leaves are then inhaled from bottom to top by passing warm, humid air containing orchid essential oil and plant-extracted amino acids in volume ratios of 1:80 and 1:30. The temperature is 25℃, the humidity is 50%, and the inhalation time is 6 hours.

[0043] S5. Drying: Hot air rapid drying + far-infrared supplementary drying combination. Hot air rapid drying: hot air temperature 90℃, hot air volume 10m / s, time 3min, leaf thickness 1cm; intermediate cooling and rehydration for 30min, leaf thickness 3cm; far-infrared supplementary drying: far-infrared temperature 60℃, leaf thickness 3cm, time 40min, until leaf moisture content <7%, approximately 6.5% in this example, finally obtaining floral and sweet white tea.

[0044] Example 2

[0045] This embodiment describes a second method for processing specialty flavored raw tea ingredients.

[0046] In this embodiment, the fresh leaves used to prepare the floral-sweet white tea were harvested from the new shoots of tea trees that had undergone 13 hours of pre-harvest light stress treatment to adapt. The tenderness of the shoots included approximately half single buds and half one bud and one leaf. The tea garden management for the 13 days prior to harvesting included fertilization and pre-harvest light stress treatment. Fertilization involved spraying the tea tree canopy with a foliar fertilizer containing 13 g / L arginine. The pre-harvest light stress treatment involved suspending light tubes or colored shade cloths and applying intermittent light stress treatments of red, blue, and yellow light. The intermittent treatment consisted of 2 hours of red light, 0.5 hours of no light, 2 hours of blue light, 0.5 hours of no light, 2 hours of yellow light, and 0.5 hours of no light to the new shoots, with a light intensity of 7500 lux, for a total of 4 cycles.

[0047] The preparation steps for fresh white tea leaves with a floral and sweet aroma are as follows:

[0048] S1. Initial withering: Fresh white tea leaves are withered using a combination of intermittent withering with red, blue, and yellow light in the dark, plus hot and cold air, and with external atomization. The initial withering of fresh white tea leaves is done with a pile thickness of 2.5cm and a humidity of 60%. In this embodiment, the withering is carried out inside a withering machine. Specifically: ① Intermittent withering with red, blue, and yellow light in the dark: The light source is 33cm away from the fresh leaves, and the light intensity is 9000 lux. During intermittent treatment, red light is on for 20 minutes, blue light for 30 minutes, yellow light for 30 minutes, and then stopped for 10 minutes, which constitutes one cycle. ② Intermittent hot and cold air variable temperature withering. Withering: 25℃ hot air blown for 18 minutes at a wind speed of 4m / s, 20℃ cold air blown for 25 minutes at a wind speed of 7m / s, and no wind for 23 minutes; ③ Atomized external additive withering: Orchid essential oil and plant-extracted amino acids were dissolved in pure water at a volume ratio of 1:110 and 1:60 to prepare an aroma-enhancing liquid. The aroma-enhancing liquid was vaporized by ultrasonic atomization. The vaporized aroma-enhancing liquid was blown from bottom to top all over the withered leaves by wind. The withering time was 28 hours until the moisture content was 42.5%.

[0049] S2. Secondary withering: This process employs a multi-functional enzyme-activated ventilation system combined with intermittent hot and cold air withering. It is carried out in a withering trough or withering machine. The fresh white tea leaves are piled to a thickness of 4.5cm, at a temperature of 27.5℃ and humidity of 70%. Specifically: ① Exogenous cellulase and lipoxygenase are dissolved in pure water at a volume ratio of 1:525 and 1:525 respectively. The dissolved enzymes are then vaporized using ultrasonic atomization. The vaporized enzyme liquid is blown upwards across the withered leaves at a wind speed of 3m / s for 1.5 hours. ② Next, the exogenous proteolytic enzyme and glycoside hydrolase were dissolved in pure water at a volume ratio of 1:425 and 1:425 respectively, and vaporized by ultrasonic atomization. The vaporized enzyme solution was blown from bottom to top over the withered leaves at a wind speed of 3 m / s for 1.5 hours. Then, intermittent hot and cold air withering was carried out: 28℃ hot air for 18 minutes at a wind speed of 4 m / s, 23℃ cold air for 23 minutes at a wind speed of 7 m / s, and no wind for 33 minutes. The withering time was 18 hours, and the leaves were withered until the moisture content was 22.5%.

[0050] S3. Cell disruption: The tea leaves are disrupted using ultrasound at 100kHz. The leaf thickness is 3cm and the disruption time is 1.2min.

[0051] S4. Fragrance inhalation: Place multi-layered shelves in the facility space, with a shelf spacing of 11cm. The tea leaves are gradually thickened from bottom to top (leaf thickness 2.5cm, 5cm, 9cm, 14cm). The tea leaves are then inhaled from bottom to top by passing warm, humid air containing orchid essential oil and plant-extracted amino acids in volume ratios of 1:90 and 1:35. The temperature is 27.5℃, the humidity is 55%, and the inhalation time is 8 hours.

[0052] S5. Drying: Hot air rapid drying + far-infrared supplementary drying combination. Hot air rapid drying: hot air temperature 95℃, hot air volume 11m / s, time 4min, leaf thickness 1.5cm; intermediate cooling and rehydration for 35min, leaf thickness 3.5cm; far-infrared supplementary drying: far-infrared temperature 65℃, leaf thickness 3.5cm, time 50min, until leaf moisture content <7%, 6.0% in this example, finally obtaining floral and sweet white tea.

[0053] Example 3

[0054] This embodiment describes the third method for processing specialty flavored raw tea ingredients.

[0055] In this embodiment, the fresh leaves used to prepare the floral-sweet white tea were harvested from the new shoots of tea trees that had undergone 15 hours of pre-harvest light stress treatment to adapt. The tenderness of the shoots included approximately half of the shoots being one bud and two leaves, and half being one bud and three leaves. The tea garden management for the 20 days prior to harvesting included fertilization and pre-harvest light stress treatment. Fertilization involved spraying the tea tree canopy with a foliar fertilizer containing 15 g / L arginine. The pre-harvest light stress treatment involved suspending light tubes or colored shading cloths and applying intermittent light stress treatments of red, blue, and yellow light. The intermittent treatment consisted of 2.5 hours of red light, 0.7 hours of no light, 2.5 hours of blue light, 0.7 hours of no light, 2.5 hours of yellow light, and 0.7 hours of no light, with a light intensity of 9000 lux, for a total of four cycles.

[0056] The preparation steps for fresh white tea leaves with a floral and sweet aroma are as follows:

[0057] S1. Initial withering: Fresh white tea leaves are withered using a combination of intermittent withering with red, blue, and yellow light in the dark, plus hot and cold air, and with external atomization. The initial withering of fresh white tea leaves is done in a 3cm thick pile with a humidity of 65%. This embodiment is carried out in a withering trough or withering machine. Specifically: ① Intermittent withering with red, blue, and yellow light in the dark: The light source is 40cm away from the fresh leaves, and the light intensity is 15000 lux. During intermittent treatment, red light is on for 25 minutes, blue light for 35 minutes, and yellow light for 35 minutes, followed by a 15-minute pause as one cycle; ② Intermittent withering with hot and cold air. The withering process involved several steps: ① **Variable wind withering:** 27℃ hot air for 20 minutes at a wind speed of 5 m / s, 22℃ cold air for 25 minutes at a wind speed of 8 m / s, followed by 25 minutes of no wind. ② **External atomized withering:** Orchid essential oil and plant-derived amino acids were dissolved in pure water at volume ratios of 1:120 and 1:70 to prepare an aroma-enhancing liquid. This liquid was then vaporized using ultrasonic atomization. The vaporized liquid was blown from bottom to top across the withered leaves. The withering time was 26 hours, until the moisture content reached 45%.

[0058] S2. Secondary withering: A multifunctional enzyme-activated ventilation system with intermittent hot and cold air withering is employed, conducted in a withering trough. The fresh white tea leaves are piled to a thickness of 5cm, at a temperature of 30℃ and humidity of 75%. The process involves: ① Dissolving exogenous cellulase and lipoxygenase in pure water at a volume ratio of 1:550 and 1:550 respectively, then vaporizing them using ultrasonic atomization. The vaporized enzyme liquid is then blown upwards over the withered leaves at a wind speed of 4m / s for 2.0 hours. ② Then... The source proteolytic enzyme and glycoside hydrolase were dissolved in pure water at a volume ratio of 1:450 and 1:450 respectively, and vaporized by ultrasonic atomization. The vaporized enzyme solution was blown over the withered leaves from bottom to top at a wind speed of 4 m / s for 2.0 hours. ③ Subsequently, intermittent hot and cold air withering was carried out: 30℃ hot air for 20 minutes at a wind speed of 5 m / s, 25℃ cold air for 25 minutes at a wind speed of 8 m / s, and no wind for 35 minutes. The withering time was 20 hours, and the leaves were withered until the moisture content was 25%.

[0059] S3. Cell disruption: The tea leaves are disrupted under high pressure (30 kPa) for 1.5 minutes. The leaf thickness is 4 cm at the time of cell disruption.

[0060] S4. Fragrance inhalation: Place multi-layered shelves in the facility space, with a shelf spacing of 12cm. The tea leaves are gradually thickened from bottom to top (leaf thickness 3cm, 6cm, 10cm, 15cm). The tea leaves are then inhaled from bottom to top by passing warm, humid air containing orchid essential oil and plant-extracted amino acids in volume ratios of 1:100 and 1:40. The temperature is 30℃, the humidity is 60%, and the inhalation time is 10 hours.

[0061] S5. Drying: Hot air rapid drying + far-infrared supplementary drying combination. Hot air rapid drying: hot air temperature 100℃, hot air volume 12m / s, time 5min, leaf thickness 2cm; intermediate cooling and rehydration for 40min, leaf thickness 4cm; far-infrared supplementary drying: far-infrared temperature 70℃, leaf thickness 4cm, time 60min, until leaf moisture content <7%, 5.5% in this example, finally obtaining floral and sweet white tea.

[0062] Comparative Examples

[0063] This embodiment describes a traditional white tea production technique, with the following steps:

[0064] S1. Tea garden management: Fertilization management, apply 200 kg / hm2 of nitrogen, phosphorus and potassium compound fertilizer, dig a 23 cm trench, and fertilize from mid to late October.

[0065] S2. White tea processing: Withering: natural bamboo flat withering in the workshop at a temperature of 20℃, leaf thickness of 2cm, withering for 48 hours until the moisture content is about 20%; Drying: temperature of 60℃, leaf thickness of 2cm, until fully dry.

[0066] The following are the sensory evaluation results of white tea samples obtained from Examples 1-3 and the comparative examples of the present invention, as shown in Table 1 below:

[0067] Table 1. Sensory evaluation results of white tea samples treated with different processing techniques in Examples 1-3 and comparative examples.

[0068]

[0069]

[0070] Using traditionally processed tea products as comparative examples, sensory evaluations were conducted together with the tea products produced by this invention, and the results are shown in Table 1. Table 1 shows that the white tea samples 1-3 produced using the complete technology of this invention exhibit a fully expanded and bud-filled appearance, a uniform and vibrant green color, a pronounced floral aroma that is fresh, delicate, and lingering, a fresh and refreshing taste with a hint of floral flavor, a bright yellow-green liquor, and tender, green, and bud-filled, uniform, and bright tea leaves. All five attributes show significant improvement, with scores at least 3 points higher than those produced using traditional methods, resulting in an overall improvement of at least one grade. This yields a high-quality, floral-sweet white tea.

[0071] The following section further compares the volatile compounds in the prepared white tea samples. Figure 1 and Figure 2 It can be seen that the white tea samples prepared by the white tea preparation process of the present invention have significantly higher levels of alcohols, aldehydes, esters, aromatic hydrocarbons, and olefins than those prepared by the traditional process. This means that the preparation technology of the present invention is conducive to the absorption and enrichment of aroma compounds by the tea sample, laying the material basis for the aroma type, intensity, persistence, and layering of the white tea's floral aroma.

[0072] Table 2 compares the typical aroma compounds OAV in floral-sweet white tea treated with different processing techniques in Examples 1-3 and the comparative examples.

[0073]

[0074]

[0075] Further analysis of typical aroma compounds in white tea (see Table 2) reveals that the white tea produced by the innovative production method of this invention contains significantly higher levels of floral and fruity aroma compounds such as benzaldehyde, octanal, phenylacetaldehyde, (3R,6S)-2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol, methyl salicylate, 2,6,6-trimethyl-1-cyclohexene-1-carboxaldehyde, (Z)-3,7-dimethyl-2,6-octadien-1-ol, geraniol, citral, and (Z)-3-hexenylhexanoic acid compared to white tea produced using traditional methods. Conversely, the grassy aroma, such as naphthalene, is significantly lower in white tea produced using traditional methods. This aligns with the sensory evaluation data, indicating that the white tea produced using the technology of this invention exhibits a sharper and more persistent floral aroma, significantly higher than that produced using traditional methods.

[0076] Table 3 Comparison of typical flavor and liquor color substance content of floral-sweet white tea processed with different techniques

[0077]

[0078] Further analysis of the typical flavor and color components of white tea (see Table 3) shows that the innovative production method of this invention significantly reduces the conversion of bitter and astringent substances such as ester-type catechins and flavonoids, while enriching substances with umami and sweetness such as theaflavins, amino acids, and soluble sugars, which are positively correlated with flavor and color. This is consistent with the sensory evaluation data, meaning that the white tea produced by the production technology of this invention has a significantly higher umami and sweetness than that produced by traditional production technology.

[0079] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention. Technical aspects, shapes, and structures not described in detail in this invention are all well-known technologies.

Claims

1. A method for processing a specialty flavored raw tea, characterized by the following steps: include: (I) Tea Garden Management; S1-1, Fertilizer Management: Spray the tea tree canopy with foliar fertilizer containing 10-15g / L arginine; S1-2, Light stress treatment: Suspend the installation of light tubes or colored shade cloths to conduct cyclical intermittent light stress treatment on the new shoots of tea trees using red light, blue light and yellow light; (II) Fresh leaf picking: Fresh leaves from new tea shoots that have adapted to light stress treatment for 10-15 hours before picking. (III) White Tea Processing; S1. First withering: Fresh leaves are withered by a combination of red, blue and yellow light-free and cold and hot air intermittently combined with atomized external source addition to obtain the first withered leaves; S2, Secondary withering: The leaves that have been withered for the first time are withered by adding multifunctional enzyme-activated ventilation and combining intermittent hot and cold air with a combination of withering to obtain leaves withered for the second time. S3. Cell disruption: Cell disruption of secondary withered leaves is achieved by high pressure or ultrasound to obtain cell-disrupted leaves. S4. Fragrance extraction: The broken leaves are fumigated with warm, humid air containing floral essential oils and plant-extracted amino acids to obtain fragrance-absorbing leaves. S5. Drying: The collected fragrant leaves are dried using a combination of hot air drying and far-infrared supplementary drying to obtain a white tea with a fresh and sweet floral aroma.

2. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: Tea garden management is carried out 15-20 days before the fresh leaves are harvested. Among them, intermittent light stress treatment is carried out on the new shoots of tea trees with red light for 1.5-2.5h, no light for 0.3-0.7h, blue light for 1.5-2.5h, no light for 0.3-0.7h, yellow light for 1.5-2.5h, and no light for 0.3-0.7h. The light intensity is 6000-9000 lux, and a total of 3-4 cycles are carried out.

3. A method for processing a specialty flavored raw tea according to claim 1 or 2, characterized in that: The tenderness of the fresh leaves includes single bud, one bud and one leaf, one bud and two leaves, and one bud and three leaves.

4. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: During the initial withering in step S1, the fresh leaves are spread out with a thickness of 2-3 cm and a humidity of 55-65%.

5. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: In step S1, during the intermittent withering process using a combination of red, blue, and yellow light without illumination and hot and cold air, the distance between the light source and the fresh white tea leaves is 25-40cm, and the light intensity is 6000-12000 lux. During the intermittent withering process using red, blue, and yellow light without illumination, the treatment cycle consists of 15-25 minutes of red light, 25-35 minutes of blue light, 25-35 minutes of yellow light, and a 5-15 minute pause. During intermittent hot and cold air withering, a cycle is formed by blowing hot air at 23-27℃ for 15-20 minutes at a wind speed of 3-5 m / s, blowing cold air at 18-22℃ for 20-25 minutes at a wind speed of 6-8 m / s, and then no wind for 20-25 minutes. During the atomized external source addition withering, floral essential oils and plant-extracted amino acids are dissolved in pure water at a volume ratio of 1:(100-120) and 1:(50-70) to prepare an aroma-enhancing liquid. The aroma-enhancing liquid is vaporized by ultrasonic atomization, and the vaporized aroma-enhancing liquid is blown from bottom to top over the withering leaves by wind. The withering time is 25-30 hours until the moisture content is 40%-45%.

6. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: During the second withering in step S2, the leaf thickness of the first withered leaves is 4-5 cm, the temperature is 25-30℃, and the humidity is 65%-75%.

7. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: The method of adding multifunctional enzyme-activated ventilation and combining intermittent hot and cold air withering in step S2 includes: dissolving exogenous cellulase and lipoxygenase in pure water at volume ratios of 1:(500-550) and 1:(500-550), respectively, vaporizing them by ultrasonic atomization, and blowing the vaporized enzyme liquid over the withering leaves from bottom to top at a wind speed of 2-4 m / s for 1.0-2.0 hours; then adding exogenous proteolytic enzyme and glycoside hydrolytic enzyme at volume ratios of 1:(400-450) and 1:( Dissolve the enzyme solution in pure water at a volume ratio of 400-450, vaporize it using ultrasonic atomization, and blow the vaporized enzyme solution over the wilted leaves from bottom to top at a wind speed of 2-4 m / s for 1.0-2.0 hours. Then, use intermittent hot and cold air for wilting: blow with hot air at 26-30℃ for 15-20 minutes at a wind speed of 3-5 m / s, blow with cold air at 21-25℃ for 20-25 minutes at a wind speed of 6-8 m / s, and then stop the wind for 30-35 minutes. The wilting time is 15-20 hours, until the leaf moisture content is 20%-25%.

8. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: In step S3, the high pressure is 20-30 kPa, and the ultrasonic frequency is 80-100 kHz; when the cells are broken, the thickness of the secondary withered leaves is 2-4 cm, and the high pressure or ultrasonic time is 1.0-1.5 min.

9. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: In step S4, during the collection and inhalation of fragrance, the cell-broken leaves are placed on a multi-layer shelf, with the thickness of the cell-broken leaves gradually increasing from bottom to top. The leaf thicknesses from bottom to top are 2-3cm, 4-6cm, 8-10cm, and 13-15cm, respectively. The leaves are then inhaled for 6-10 hours by passing warm, humid air containing floral essential oils and plant-extracted amino acids in volume ratios of 1:(80-100) and 1:(30-40). The temperature of the warm, humid air is 25-30℃, and the humidity is 50-60%.

10. The method for processing a specialty flavored raw tea according to claim 1, characterized in that: In step S5, the drying process employs a combination of hot air rapid drying and far-infrared supplementary drying. The hot air rapid drying uses a hot air temperature of 90-100℃, a hot air volume of 10-12 m / s, and a drying time of 3-5 min, resulting in a leaf thickness of 1-2 cm. The leaves are then spread out to cool and rehydrate for 30-40 min, achieving a leaf thickness of 3-4 cm. The far-infrared supplementary drying uses a far-infrared temperature of 60-70℃, a leaf thickness of 3-4 cm, and a drying time of 40-60 min, until the moisture content is <7%.

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