A new comprehensive processing technique for improving the quality of summer and autumn black tea

Abstract

This invention belongs to the field of tea processing technology. It provides a novel comprehensive processing technique for improving the quality of summer and autumn black tea, comprising the steps of gentle shaking combined with UV-B-LED combined spectral withering, low-temperature controlled pressure gradient kneading, three-parameter linked dynamic fermentation, microwave-hot air coupled drying, and far-infrared variable-temperature aroma enhancement. Gentle shaking combined with UV-B-LED combined spectroscopy promotes the polymerization and transformation of flavor components; low-temperature controlled pressure gradient kneading allows for controllable cell breakage of tea leaves, promoting the outflow of tea juice; three-parameter linked dynamic fermentation increases the content of theaflavins and aromatic substances, improving the uniformity of fermentation; microwave-hot air coupled drying reduces aroma loss and improves drying efficiency; far-infrared variable-temperature aroma enhancement enriches the aroma of the tea, improves tea quality, and enhances the harmony and lasting sweetness of the tea soup. The resulting black tea has a complex aroma of flowers and honey, a bright red liquor, a mellow and refreshing taste, and a comprehensive sensory score as high as 95.6.

Description

Technical Field

[0001] This invention relates to the field of tea processing technology, and in particular to a new comprehensive control processing technology for improving the quality of summer and autumn black tea. Background Technology

[0002] Summer and autumn teas are among the main raw materials for black tea processing, characterized by abundant yields and concentrated seasonality. However, due to the influence of the ecological environment and the harvesting season, their fresh leaves generally suffer from natural disadvantages such as an imbalance in the proportion of internal components, a stronger bitter and astringent taste, and a lower content of aroma substances. Compared with spring tea, summer and autumn teas show a significant decrease in amino acid content, while the content of bitter and astringent substances such as tea polyphenols and catechins increases significantly, resulting in noticeable differences in flavor harmony, aroma type, and liquor brightness among summer and autumn black teas. Therefore, despite the abundance of summer and autumn tea resources, their high-value development has long been limited due to unstable quality and low levels of deep processing.

[0003] Current black tea processing technology mainly includes conventional processes such as withering, rolling, fermentation, and drying. The overall process has followed traditional methods for many years, with relatively fixed technical routes, lacking systematic and precise control methods for improving the quality of summer and autumn teas. In the withering stage, indoor natural withering, sun withering, or withering troughs are commonly used. Natural withering is significantly affected by environmental factors such as weather, temperature, and humidity, taking a long time and being inefficient, often leading to unstable control of the withering process. Sun withering is short, efficient, and low-cost, but easily affected by weather, making it difficult to control the quality and intensity of outdoor sunlight, which can easily cause instability in tea quality. Withering in troughs is prone to uneven heat distribution and excessive water loss from the leaf surface, resulting in significant differences in moisture content between the inside and outside of the leaves. This leads to insufficient or uneven enzymatic conversion of aroma precursors, making the foundation for subsequent quality formation less than ideal.

[0004] During the rolling process, traditional techniques rely heavily on experience to adjust rolling time, pressure, and speed, lacking clear quantitative standards. Because the degree of cell breakage is not easily judged visually, consistent rolling intensity control is difficult, leading to significant fluctuations in tea juice overflow between batches. Insufficient cell breakage affects the supply of substrates for polyphenol oxidation during fermentation, while excessive rolling can cause excessive tissue damage and increased bitterness, both detrimental to the formation of a harmonious flavor base. Fermentation is a crucial step in shaping the quality of black tea. Common fermentation methods include indoor natural fermentation, fermentation boxes, and fermentation carts. Traditional black tea fermentation processes employ static stacking, often resulting in insufficient oxygen, uneven fermentation, and temperature deviations between the upper, middle, and lower layers, easily leading to impure aromas and bitter tastes in the finished product. Determining the degree of fermentation usually relies on manual assessment using sensory indicators such as changes in leaf color and aroma, heavily dependent on experience and highly subjective, making it difficult to achieve uniform and appropriate polyphenol oxidation using traditional methods. Insufficient fermentation results in a bland aroma and pale liquor; excessive fermentation leads to a dull aroma, dark brown liquor, and prominent astringency, severely impacting the quality stability of the finished black tea. Hot air drying is the primary method, a traditional and widely used technique, but it suffers from drawbacks such as low heat utilization, high energy consumption, and uneven heating. High-temperature hot air can cause significant loss of volatile aromatic compounds in the early stages of drying, affecting the preservation of the tea's aroma; while in the later stages, a "dry outside, moist inside" phenomenon may occur, making the finished tea prone to moisture absorption and quality instability during storage.

[0005] In addition, the composition of the fresh leaves of summer and autumn tea is unbalanced, with a high proportion of tea polyphenols and low content of amino acids and aromatic precursors. Traditional processing methods are difficult to control according to their quality characteristics, and it is often difficult to produce high-quality summer and autumn black tea with a prominent aroma, mellow taste and bright liquor.

[0006] In summary, due to numerous technical bottlenecks in enhancing the aroma, improving the harmony of flavor, and stabilizing the quality of summer and autumn black tea, existing processes are insufficient to fully tap the potential quality of summer and autumn tea raw materials. Therefore, researching and developing a new comprehensive processing technology for improving the quality of summer and autumn black tea, capable of systematically controlling the shortcomings of summer and autumn tea, holds great promise.

[0007] In recent years, research on the regulation of plant raw material components has gradually incorporated new approaches such as spectral regulation and process dynamics. Among these, ultraviolet B (UV-B, 280~320nm), as an important component of sunlight, can be absorbed by biomolecules such as proteins and nucleic acids, thereby inducing a series of physiological and metabolic responses in plants. Existing studies have shown that moderate UV-B radiation can enhance the activity of various endogenous enzymes such as polyphenol oxidase and phenylalanine ammonia-lyase, and induce the accumulation of volatile substances and their secondary metabolites in plants, exhibiting significant biological effects in regulating the composition of plant components. Meanwhile, light-emitting diode (LED) light sources have received widespread attention in plant growth regulation and agricultural product processing due to their tunable spectral composition and high energy utilization efficiency. Existing research has shown that combinations of LED light in different wavelength bands can, to some extent, simulate the characteristics of the natural spectrum, and that light conditions themselves are important inducing factors for tea aroma formation. After sun withering, tea leaves can significantly increase the activity of enzymes such as polyphenol oxidase and peroxidase, providing favorable conditions for the transformation of aroma precursors. However, existing solar withering methods are greatly affected by the natural environment, making it difficult to achieve stable and controllable spectral conditions.

[0008] In the fermentation process, traditional black tea processing often employs a static, stacked fermentation method. This limits gas exchange and heat transfer within the tea leaves, easily leading to insufficient oxygen supply, uneven temperature and humidity distribution, and significant differences in fermentation levels. In recent years, dynamic fermentation, as an improved method, introduces dynamic control techniques such as turning and ventilation during fermentation. This improves oxygen supply and heat distribution within the tea leaves, promoting more uniform polyphenol oxidation and enhancing the controllability and consistency of the fermentation process. However, current research on dynamic fermentation largely focuses on optimizing single process parameters and has not yet achieved synergistic integration with upstream withering control methods.

[0009] Overall, although technologies such as UV-B radiation regulation, LED spectral regulation, and dynamic fermentation have a certain research foundation in plant physiological regulation and tea processing, their application in summer and autumn black tea processing is still mainly based on scattered exploration. There is a lack of mature technical solutions for systematic and synergistic regulation of key processes such as withering, rolling, fermentation, and drying, specifically addressing the imbalance of components in summer and autumn tea raw materials. Therefore, how to organically combine spectral regulation with dynamic processing to construct a new comprehensive regulatory processing technology suitable for the characteristics of summer and autumn tea raw materials still requires further research and development. Summary of the Invention

[0010] The purpose of this invention is to address the common problems in existing summer and autumn black tea processing techniques, such as the withering process being highly susceptible to environmental influences and limited control methods, the rolling process relying on experience and struggling to maintain consistent intensity, the fermentation process often employing static methods with insufficient uniformity and controllability, and the drying process easily leading to the loss of aroma substances and insufficient quality stability. This invention provides a new comprehensive and synergistic processing technology for improving the quality of summer and autumn black tea. This technology introduces controllable spectral conditions during the withering stage, implements pressure gradient control under low-temperature conditions during the rolling stage, employs a multi-parameter linked dynamic fermentation method during the fermentation stage, and combines microwave and hot air coupled drying with far-infrared variable-temperature aroma enhancement treatment. This achieves systematic and coordinated control of key processing steps in summer and autumn black tea processing, thereby specifically addressing the structural imbalance of the raw materials during processing and improving the controllability and stability of the processing.

[0011] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a novel comprehensive processing technique for improving the quality of summer and autumn black tea, comprising the following steps: 1) Gentle shaking combined with UV-B-LED spectral regulation of withering: Summer and autumn tea leaves are spread out in an environment with a wavelength of 450-600 nm and a photosynthetic photon flux density of... Withering is carried out under LED light source; when the moisture content of fresh tea leaves drops to 68-73%, UV-B irradiation with a wavelength of 280-320nm and an intensity of 15-25μW / cm² is applied to the withered leaves. During the UV-B irradiation, the oolong tea light shaking process is introduced simultaneously, and the leaves are shaken once every two hours for a total of four times. The first shaking lasts for 2-4 minutes, the second for 4-6 minutes, the third for 8-12 minutes, and the fourth for 18-22 minutes, so that the moisture content of fresh tea leaves drops to 58-63%. 2) Low-temperature controlled pressure gradient rolling: The withered leaves are rolled in three stages: low pressure, medium pressure and high pressure, and the rolling environment temperature is controlled at 20~25℃. 3) Three-parameter linkage dynamic fermentation: The kneaded leaves are dynamically fermented under the conditions of temperature of 25~30℃, relative humidity of 85~95%, and oxygen content of 21~35%; 4) Microwave-hot air coupled drying: First, microwave heating is used to pre-dry the fermented leaves, reducing the moisture content of the tea to 15-25%. Then, the pre-dried tea is spread out to cool for 40-60 minutes, and then box-type hot air drying is used to reduce the moisture content of the tea to 4-6%. 5) Far-infrared temperature-controlled aroma enhancement: Far-infrared heating is used to enhance the aroma of tea leaves, and temperature control is implemented in stages during the aroma enhancement process to obtain high-quality summer and autumn black tea. The phased temperature control is as follows: First stage: enhance the aroma of tea leaves at 80~90℃ for 50~70 minutes; Second stage: raise the temperature to 95~105℃ and continue to enhance the aroma for 20~40 minutes; Third stage: further raise the temperature to 115~125℃ and enhance the aroma for 5~10 minutes.

[0012] Preferably, the summer and autumn tea leaves mentioned in step 1) are mature fresh leaves with one bud and two leaves or one bud and three leaves picked in summer or autumn.

[0013] Preferably, the withering temperature in step 1) is 22~28℃ and the relative humidity is 50~70%.

[0014] Preferably, the thickness of the spreading in step 1) is 2-4 cm, and it is turned over 2-3 times during the spreading process.

[0015] Preferably, in step 2), the force of low-pressure kneading is 50~70N, the force of medium-pressure kneading is 80~100N, and the force of high-pressure kneading is 120~150N.

[0016] Preferably, the total kneading time in step 2) is 45-60 minutes, wherein the ratio of low-pressure, medium-pressure, and high-pressure kneading time is 2-3:2-4:2-3.

[0017] Preferably, the thickness of the leaf spread during dynamic fermentation in step 3) is 6-8 cm.

[0018] Preferably, the total time for dynamic fermentation in step 3) is 2-4 hours, and during the dynamic fermentation process, the kneading leaves are turned over every 45-70 minutes, with each turn lasting 2-4 minutes.

[0019] Preferably, the microwave heating in step 4) is performed at a temperature of 105~115℃, a power of 400~600W, and a time of 8~10min.

[0020] Preferably, the temperature of the box-type hot air drying in step 4) is 85~95℃ and the time is 30~50min.

[0021] The beneficial effects of this invention include the following: 1) This invention introduces UV-B radiation and LED combined light synergistically into the withering process of black tea, and regulates the physiological metabolism of fresh tea leaves under controllable spectral conditions. This is beneficial to influencing the transformation behavior of polyphenols, amino acids and other internal components, providing the basic conditions for the formation of flavor quality of summer and autumn black tea. At the same time, LED combined light helps to maintain the activity state of related enzyme systems during withering, promotes the formation and transformation of aromatic precursor substances, and lays the foundation for subsequent aroma formation.

[0022] 2) This invention introduces a shaking process in the withering stage of black tea. Through gentle collision and friction, the edge cells of the leaves are moderately damaged, which helps to induce related enzymatic reactions and promote the formation of aroma and flavor precursors, thereby creating conditions for the construction of aroma and flavor characteristics in subsequent processing.

[0023] 3) In the rolling process, the present invention adopts a low-pressure-medium-high-pressure gradient rolling method under low temperature conditions, so that the tea cells can be broken more evenly during the step-by-step force process, which is conducive to the stable overflow of tea juice, thereby improving the consistency and controllability of the rolling process; the low temperature rolling condition helps to maintain the stable state of the endogenous enzyme system, providing a more stable reaction basis for the oxidation reaction in the subsequent fermentation process.

[0024] 4) This invention, by linking and regulating the temperature, humidity and oxygen content during the fermentation process and combining it with a dynamic turning method, helps to improve the problems of uneven temperature and humidity distribution and limited gas exchange that are prone to occur in traditional static fermentation. This makes the fermentation environment parameters more uniform and controllable, which is conducive to the stable progress of the fermentation process and improves the consistency of fermentation.

[0025] 5) This invention adopts a coupled drying method combining microwave and hot air. First, microwave initial drying achieves rapid and uniform dehydration, which is conducive to timely termination of the fermentation process and fixation of the formed quality characteristics. Then, box-type hot air drying is used for further dehydration, which helps to avoid excessive volatilization of aroma substances and problems such as "dry outside and wet inside" in the process of single high temperature drying, thereby improving the stability of the drying process while taking into account the drying efficiency.

[0026] 6) In the aroma enhancement stage, the present invention adopts far-infrared variable temperature aroma enhancement method. Through staged temperature control, the tea leaves gradually complete the release and transformation of aroma substances under different temperature conditions, which helps to enrich the aroma composition and improve the harmony of aroma. At the same time, the variable temperature aroma enhancement method can reduce the risk of heat damage to aroma substances caused by single high temperature treatment, thereby helping to improve the stability of aroma quality of summer and autumn black tea.

[0027] 7) Under the synergistic effect of each process, the summer and autumn black tea obtained by this invention has tightly rolled leaves, dark and shiny with white hairs, bright red and clear liquor, mellow and refreshing taste, rich and harmonious aroma, and a comprehensive sensory score that is significantly higher than that of samples made with traditional processes. It has outstanding technological innovation and application value. Attached Figure Description

[0028] Figure 1 This is a comparison chart showing the percentage content of theaflavins in the black tea products of Example 1 and Comparative Example 1. Figure 2 This is a comparison chart showing the relative contents of volatile substances such as terpenoids, phenylethyl alcohol, geraniol, and methyl salicylate in the black tea products of Example 1 and Comparative Example 1. Detailed Implementation

[0029] This invention provides a novel comprehensive processing technique for improving the quality of summer and autumn black tea, comprising the following steps: 1) Gentle shaking combined with UV-B-LED spectral regulation of withering: Fresh summer and autumn tea leaves are spread out in an environment with a wavelength of 450~600nm, preferably 480~580nm, more preferably 500~550nm, and even more preferably 520~530nm, where the photosynthetic photon flux density is... Preferred Further optimized More preferably Withering is carried out under an LED light source; when the moisture content of the fresh tea leaves drops to 68-73%, preferably 69-72%, more preferably 70-71%, the withering leaves are subjected to an irradiation with a wavelength of 280-320 nm, preferably 290-310 nm, more preferably 295-300 nm, and an irradiation intensity of 15-25 μW / cm², preferably 18-24 μW / cm², more preferably 20-22 μW / cm². Irradiate, and During the irradiation period, a light shaking process for oolong tea is introduced simultaneously. Preferably, the tea is shaken once every two hours, for a total of four shakings. The first shaking lasts for 2-4 minutes, preferably 3 minutes; the second shaking lasts for 4-6 minutes, preferably 5 minutes; the third shaking lasts for 8-12 minutes, preferably 10 minutes; and the fourth shaking lasts for 18-22 minutes, preferably 20 minutes. This reduces the moisture content of the fresh tea leaves to 58-63%, preferably 60-62%, and more preferably 61%. 2) Low-temperature controlled pressure gradient kneading: The wilted leaves are kneaded in three stages: low pressure, medium pressure and high pressure. The kneading environment temperature is preferably 20~25℃, and more preferably 22~23℃. 3) Three-parameter linkage dynamic fermentation: The kneaded leaves are dynamically fermented under the following conditions: temperature of 25~30℃, preferably 26~28℃, relative humidity of 85~95%, preferably 88~92%, further preferably 90%, and oxygen content of 21~35%, preferably 25~30%, further preferably 26~28%. 4) Microwave-hot air coupled drying: First, microwave heating is used to pre-dry the fermented leaves, reducing the moisture content of the tea to 15-25%, preferably 18-22%, and more preferably 20%. Then, the pre-dried tea is spread out to cool for 40-60 minutes, preferably 45-55 minutes, and more preferably 50 minutes. Finally, box-type hot air drying is used to reduce the moisture content of the tea to 4-6%, and more preferably 5%. 5) Far-infrared temperature-controlled aroma enhancement: Far-infrared heating is used to enhance the aroma of tea leaves, and temperature control is implemented in stages during the aroma enhancement process to obtain high-quality summer and autumn black tea. The phased temperature control is specifically as follows: First stage: the tea is preferably infused with aroma at 80~90℃ for 50~70 minutes, more preferably at 84~86℃ for 55~65 minutes, and even more preferably at 85℃ for 60 minutes; Second stage: the temperature is preferably raised to 95~105℃ and infused with aroma for 20~40 minutes, more preferably at 100℃ and infused with aroma for 30 minutes; Third stage: the temperature is preferably raised to 115~125℃ and infused with aroma for 5~10 minutes, and even more preferably at 120℃ and infused with aroma for 8 minutes.

[0030] In this invention, the summer and autumn tea leaves mentioned in step 1) are preferably mature fresh leaves with one bud and two leaves or one bud and three leaves picked in summer or autumn.

[0031] In this invention, the withering temperature in step 1) is preferably 22~28℃, more preferably 24~26℃, and even more preferably 25℃; the relative humidity is preferably 50~70%, more preferably 55~65%, and even more preferably 60%.

[0032] In this invention, the thickness of the spreading in step 1) is preferably 2-4 cm, more preferably 2.5-3.5 cm, and even more preferably 3 cm; during the spreading period, it is preferably turned over 2-3 times, and more preferably 3 times.

[0033] In this invention, a controllable LED combined light source and UV-B radiation are introduced during the withering stage. This can simulate natural light conditions to a certain extent and induce physiological metabolic processes in fresh tea leaves. LED visible light irradiation helps maintain the activity of relevant enzyme systems within the leaves, promoting the formation and accumulation of aroma precursors. Moderate UV-B radiation can be absorbed by biomolecules within the leaves, triggering physiological responses and influencing secondary metabolic processes, thus providing the foundation for subsequent aroma and flavor transformation. Simultaneously, gentle shaking is introduced during withering, which improves the moisture distribution within the leaves through mild mechanical stimulation, promotes intercellular material exchange, and activates key metabolic genes in the leaves. This promotes lipid degradation, the production of coupled oxidation products, hydrolysis, and the transformation of glycosides, laying a solid material foundation for improving the quality of summer and autumn black tea. Through the synergistic effect of spectral regulation and gentle shaking, a more consistent raw material base can be provided for subsequent rolling and fermentation processes.

[0034] In this invention, the force of low-pressure kneading in step 2) is preferably 50~70N, more preferably 55~65N, and even more preferably 60N; the force of medium-pressure kneading is preferably 80~100N, more preferably 85~95N, and even more preferably 90N; and the force of high-pressure kneading is preferably 120~150N, more preferably 130~140N, and even more preferably 135N.

[0035] In this invention, the total kneading time in step 2) is preferably 45-60 min, more preferably 50-55 min, and even more preferably 52 min; wherein the time ratio of low pressure, medium pressure and high pressure kneading is preferably 2-3:2-4:2-3, and more preferably 2.5:3:2.5.

[0036] In this invention, a low-pressure-medium-high-pressure gradient kneading method under low-temperature conditions is employed in the kneading process, allowing tea cells to gradually break down under progressive stress. Compared to traditional single high-intensity kneading, this method helps avoid excessive tissue breakage and fragmentation caused by excessive localized stress, resulting in a more uniform and stable tea juice overflow process. Furthermore, kneading at low temperatures helps reduce the temperature rise caused by friction and mechanical action during the kneading process, slowing down fluctuations in endogenous enzyme activity. This provides more stable substrate release conditions for subsequent fermentation reactions, contributing to improved consistency and controllability of the kneading process.

[0037] In this invention, the thickness of the leaf spread during dynamic fermentation in step 3) is preferably 6-8 cm, more preferably 6.5-7.5 cm, and even more preferably 7 cm.

[0038] In this invention, the total time for dynamic fermentation in step 3) is preferably 2-4 hours, more preferably 2.5-3.5 hours, and even more preferably 3 hours; and during the dynamic fermentation process, the kneading leaves are preferably turned over once every 45-70 minutes, more preferably once every 50-60 minutes, and each turning is preferably lasting 2-4 minutes, more preferably lasting 3 minutes.

[0039] In this invention, during the fermentation stage, by synergistically regulating temperature, relative humidity, and oxygen content, and introducing dynamic turning during fermentation, problems such as insufficient oxygen supply and uneven temperature and humidity distribution that easily occur in traditional static stacking fermentation can be improved. Dynamic turning helps promote gas exchange and heat transfer within the leaf layer, making the fermentation environment more uniform, which is conducive to the simultaneous oxidation reaction of polyphenols within the leaves. Through multi-parameter linkage regulation, the controllability and repeatability of the fermentation process can be improved, reducing the risk of quality fluctuations caused by uneven fermentation, and creating conditions for the formation of a stable aroma and flavor base for black tea.

[0040] In this invention, the microwave heating temperature in step 4) is preferably 105~115℃, more preferably 108~112℃, and even more preferably 110℃; the power is preferably 400~600W, more preferably 450~550W, and even more preferably 500W; and the time is preferably 8~10min, and even more preferably 9min.

[0041] In this invention, the temperature of the box-type hot air drying in step 4) is preferably 85~95℃, more preferably 88~92℃, and even more preferably 90℃; the time is preferably 30~50min, more preferably 35~45min, and even more preferably 40min.

[0042] In this invention, the fermented leaves are first initially dried using microwave heating during the drying process. Microwave heating, with its volumetric heating characteristic, allows moisture to migrate from the inside of the tea leaves to the outside, achieving rapid dehydration in a short time. This facilitates the timely termination of the fermentation reaction and the fixation of established quality characteristics. Subsequently, box-type hot air drying is used for further dehydration. Through a relatively gentle and uniform hot air heat transfer method, the moisture content of the tea leaves is gradually reduced to the required range for the finished product. This helps avoid problems such as the volatilization of aroma substances and "dry outside, moist inside" issues that can easily occur during high-temperature drying alone. The coupled application of microwaves and hot air helps to balance drying efficiency and quality stability.

[0043] In the aroma enhancement stage, far-infrared heating with phased temperature control is employed to achieve a more uniform heating effect on the tea leaves through far-infrared radiation. Phased heating helps to gradually stimulate the release and transformation of different aroma components in the tea leaves, avoiding excessive volatilization or heat damage of aroma substances under a single high-temperature condition. By rationally controlling the aroma enhancement temperature and time, the aroma characteristics can be further regulated while stabilizing the moisture content of the dry tea, contributing to improving the harmony and stability of the aroma in the finished black tea.

[0044] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0045] Example 1: Mature fresh leaves (one bud and two leaves) harvested in summer are evenly spread on a clean withering rack to a thickness of 3 cm. Withering is then carried out under conditions of 25℃ and 60% relative humidity. The withering process is conducted at a wavelength of 500 nm and a photosynthetic photon flux density of... The tea leaves were treated with LED light source and turned three times during withering. When the moisture content of the tea leaves dropped to 72%, they were irradiated with UV-B at a wavelength of 300nm and an intensity of 20μW / cm². During the UV-B irradiation, a light shaking process was introduced simultaneously, with shaking performed every two hours for a total of four times. The shaking time was 3 minutes for the first time, 5 minutes for the second time, 10 minutes for the third time, and 20 minutes for the fourth time. Withering continued until the moisture content of the tea leaves dropped to 62%.

[0046] Subsequently, the withered leaves were subjected to low-temperature controlled pressure gradient kneading, with the kneading environment temperature controlled at 25℃. The kneading process consisted of three stages: low pressure, medium pressure, and high pressure. In the low pressure stage, a force of 60N was applied for kneading for 18 minutes; in the medium pressure stage, a force of 90N was applied for kneading for 24 minutes; and in the high pressure stage, a force of 130N was applied for kneading for 18 minutes. The total kneading time was 60 minutes.

[0047] After kneading, spread the kneaded leaves evenly on the fermentation tray to a thickness of 7cm. Then, carry out dynamic fermentation under the conditions of 30℃, 90% relative humidity and 25% oxygen content for a total fermentation time of 3 hours. During the dynamic fermentation process, the kneaded leaves are turned over every 60 minutes, with each turn lasting 2 minutes.

[0048] After fermentation, the fermented leaves are initially dried using microwave heating at 110℃, 500W, for 10 minutes, reducing the moisture content to 20%. The initially dried leaves are then spread out to cool for 50 minutes. After cooling, a box-type hot air system is used for final drying at 90℃ for 40 minutes, reducing the moisture content to 5%.

[0049] Finally, the dried tea leaves are subjected to far-infrared variable-temperature aroma enhancement treatment. The aroma enhancement process is carried out in stages with variable-temperature control. In the first stage, the aroma is enhanced at 85℃ for 60 minutes; in the second stage, the temperature is raised to 100℃ and the aroma is enhanced for another 30 minutes; in the third stage, the temperature is further raised to 120℃ and the aroma is enhanced for another 8 minutes, resulting in high-quality summer and autumn black tea.

[0050] Sensory evaluation was conducted on the summer and autumn black tea obtained in this embodiment (referring to the national standard GB / T 23776). The results showed that the obtained summer and autumn black tea had tightly rolled leaves, a dark and lustrous color with visible white down, a complex aroma of floral honey and floral notes, a bright and clear red tea liquor, a mellow and refreshing taste with a distinct sweet aftertaste, and bright and evenly red tea leaves. The overall sensory score was 95.6.

[0051] The theaflavins and volatile components of the obtained black tea product were analyzed. The results showed that the total theaflavin content was 0.58% (the percentages of each theaflavin monomer were: TF 0.07%, TF-3G 0.10%, TF-3'G 0.05%, and TFDG 0.36%). Among the volatile aroma components, terpenoids and their oxidation products were the main components, with a relative content of 19.94% for terpenoids, 5.98% for phenylethanol, 13.34% for geraniols, and 11.67% for methyl salicylates.

[0052] Further analysis was conducted on the tea polyphenols, total flavonoids, ester-type catechins, and phenol-to-amino acid ratio of the black tea product. The results showed that the tea polyphenol content in the sample was 16.25%, the total flavonoid content was 3.21%, the ester-type catechin content was 5.45%, and the phenol-to-amino acid ratio was 7.21.

[0053] Example 2: Mature fresh leaves (one bud and three leaves) harvested in summer are evenly spread on a clean withering rack to a thickness of 2 cm. Withering is then carried out under conditions of 22℃ and 70% relative humidity. The withering process is conducted at a wavelength of 450 nm and a photosynthetic photon flux density of... The tea leaves were treated with LED light source and turned twice during withering. When the moisture content of the tea leaves dropped to 73%, they were irradiated with UV-B at a wavelength of 280nm and an intensity of 25μW / cm². During the UV-B irradiation, a light shaking process was introduced simultaneously, with shaking performed every two hours for a total of four times. The shaking time was 2 minutes for the first time, 6 minutes for the second time, 8 minutes for the third time, and 22 minutes for the fourth time. Withering continued until the moisture content of the tea leaves dropped to 63%.

[0054] Subsequently, the withered leaves were subjected to low-temperature controlled pressure gradient kneading, with the kneading environment temperature controlled at 20℃. The kneading process consisted of three stages: low pressure, medium pressure, and high pressure. In the low pressure stage, a force of 50N was applied for kneading for 15 minutes; in the medium pressure stage, a force of 80N was applied for kneading for 15 minutes; and in the high pressure stage, a force of 120N was applied for kneading for 15 minutes. The total kneading time was 45 minutes.

[0055] After kneading, spread the kneaded leaves evenly on the fermentation tray to a thickness of 6cm. Then, carry out dynamic fermentation under the conditions of 25℃, 95% relative humidity and 21% oxygen content for a total fermentation time of 4 hours. During the dynamic fermentation process, the kneaded leaves are turned over every 45 minutes, with each turn lasting 4 minutes.

[0056] After fermentation, the fermented leaves are initially dried using microwave heating at 105℃, 600W, for 8 minutes, reducing the moisture content to 25%. The initially dried leaves are then spread out to cool for 60 minutes. After cooling, a box-type hot air system is used for final drying at 85℃ for 50 minutes, reducing the moisture content to 6%.

[0057] Finally, the dried tea leaves are subjected to far-infrared variable-temperature aroma enhancement treatment. The aroma enhancement process is carried out in stages with variable-temperature control. In the first stage, the aroma is enhanced at 80℃ for 70 minutes; in the second stage, the temperature is raised to 95℃ and the aroma is enhanced for another 40 minutes; in the third stage, the temperature is further raised to 125℃ and the aroma is enhanced for another 5 minutes, resulting in high-quality summer and autumn black tea.

[0058] Sensory evaluation was conducted on the summer and autumn black tea obtained in this embodiment (referring to the national standard GB / T 23776). The results showed that the obtained summer and autumn black tea had tightly rolled leaves, a dark and lustrous color with visible white down, a complex aroma of floral honey and floral notes, a bright and clear red tea liquor, a mellow and refreshing taste with a distinct sweet aftertaste, and bright and evenly red tea leaves. The overall sensory score was 94.5.

[0059] The theaflavins and volatile components of the obtained black tea product were analyzed. The results showed that the total theaflavins content was 0.57%. Among the volatile aroma components, terpenoids and their oxidation products were the main components, with a relative content of 19.85% for terpenoids, 5.63% for phenylethanol, 12.98% for geraniol, and 11.32% for methyl salicylate.

[0060] Further analysis was conducted on the tea polyphenols, total flavonoids, ester-type catechins, and phenol-to-amino acid ratio of the black tea product. The results showed that the tea polyphenol content in the sample was 14.69%, the total flavonoid content was 2.65%, the ester-type catechin content was 5.03%, and the phenol-to-amino acid ratio was 6.48.

[0061] Example 3: Mature fresh leaves (one bud and two leaves) harvested in autumn are evenly spread on a clean withering rack to a thickness of 4 cm. Withering is then carried out under conditions of 28℃ and 50% relative humidity. The withering process is conducted at a wavelength of 600 nm and a photosynthetic photon flux density of... The tea leaves were treated with LED light and turned three times during withering. When the moisture content of the tea leaves dropped to 70%, they were irradiated with UV-B light at a wavelength of 320nm and an intensity of 15μW / cm². During the UV-B irradiation, a light shaking process was introduced simultaneously, with shaking performed every two hours for a total of four times. The shaking times were 4 minutes for the first time, 4 minutes for the second time, 12 minutes for the third time, and 18 minutes for the fourth time. Withering continued until the moisture content of the tea leaves dropped to 60%.

[0062] Subsequently, the withered leaves were subjected to low-temperature controlled pressure gradient kneading, with the kneading environment temperature controlled at 23℃. The kneading process consisted of three stages: low pressure, medium pressure, and high pressure. In the low pressure stage, a force of 70N was applied for kneading for 15 minutes; in the medium pressure stage, a force of 100N was applied for kneading for 20 minutes; and in the high pressure stage, a force of 150N was applied for kneading for 15 minutes. The total kneading time was 50 minutes.

[0063] After kneading, spread the kneaded leaves evenly on the fermentation tray to a thickness of 8cm. Then, carry out dynamic fermentation under the conditions of 28℃, 85% relative humidity and 35% oxygen content for a total fermentation time of 2 hours. During the dynamic fermentation process, the kneaded leaves are turned over every 70 minutes, and each turn lasts for 3 minutes.

[0064] After fermentation, the fermented leaves are initially dried using microwave heating at 115℃, 400W, for 9 minutes, reducing the moisture content to 15%. The initially dried leaves are then spread out to cool for 40 minutes. After cooling, a box-type hot air system is used for final drying at 95℃ for 30 minutes, reducing the moisture content to 4%.

[0065] Finally, the dried tea leaves are subjected to far-infrared temperature-controlled aroma enhancement treatment. The aroma enhancement process is carried out in stages with temperature control. In the first stage, the aroma is enhanced at 90℃ for 50 minutes; in the second stage, the temperature is raised to 105℃ and the aroma is enhanced for another 20 minutes; in the third stage, the temperature is further raised to 115℃ and the aroma is enhanced for another 10 minutes, resulting in high-quality summer and autumn black tea.

[0066] Sensory evaluation was conducted on the summer and autumn black tea obtained in this embodiment (referring to the national standard GB / T 23776). The results showed that the obtained summer and autumn black tea had tightly rolled leaves, a dark and lustrous color with visible white down, a complex aroma of floral honey and floral notes, a bright and clear red tea liquor, a mellow and refreshing taste with a distinct sweet aftertaste, and bright and evenly red tea leaves. The overall sensory score was 95.2.

[0067] The theaflavins and volatile components of the obtained black tea product were analyzed. The results showed that the total theaflavins content was 0.55%. Among the volatile aroma components, terpenoids and their oxidation products were the main components, with a relative content of 18.24% for terpenoids, 6.02% for phenylethanol, 14.12% for geraniol, and 10.96% for methyl salicylate.

[0068] Further analysis was conducted on the tea polyphenols, total flavonoids, ester-type catechins, and phenol-to-amino acid ratio of the black tea product. The results showed that the tea polyphenol content in the sample was 17.05%, the total flavonoid content was 2.67%, the ester-type catechin content was 6.03%, and the phenol-to-amino acid ratio was 7.02.

[0069] Example 4: Mature fresh leaves (one bud and three leaves) harvested in autumn are evenly spread on a clean withering rack to a thickness of 3 cm. Withering is then carried out under conditions of 25℃ and 65% relative humidity. The withering process is conducted at a wavelength of 550 nm and a photosynthetic photon flux density of... The tea leaves were treated with LED light and turned three times during withering. When the moisture content of the tea leaves dropped to 68%, they were irradiated with UV-B light at a wavelength of 300nm and an intensity of 15μW / cm². During the UV-B irradiation, a light shaking process was introduced simultaneously, with shaking performed every two hours for a total of four times. The shaking time was 3 minutes for the first time, 5 minutes for the second time, 10 minutes for the third time, and 20 minutes for the fourth time. Withering continued until the moisture content of the tea leaves dropped to 58%.

[0070] Subsequently, the withered leaves were subjected to low-temperature controlled pressure gradient kneading, with the kneading environment temperature controlled at 25℃. The kneading process consisted of three stages: low pressure, medium pressure, and high pressure. In the low pressure stage, a force of 55N was applied for kneading for 15 minutes; in the medium pressure stage, a force of 85N was applied for kneading for 20 minutes; and in the high pressure stage, a force of 135N was applied for kneading for 15 minutes. The total kneading time was 50 minutes.

[0071] After kneading, spread the kneaded leaves evenly on the fermentation tray to a thickness of 8cm. Then, carry out dynamic fermentation under the conditions of 30℃, 95% relative humidity and 30% oxygen content for a total fermentation time of 3 hours. During the dynamic fermentation process, the kneaded leaves are turned over every 60 minutes, with each turn lasting 2 minutes.

[0072] After fermentation, the fermented leaves are initially dried using microwave heating at 110℃, 600W, for 10 minutes, reducing the moisture content to 20%. The initially dried leaves are then spread out to cool for 50 minutes. After cooling, a box-type hot air drying system is used for final drying at 90℃ for 50 minutes, reducing the moisture content to 5%.

[0073] Finally, the dried tea leaves are subjected to far-infrared variable-temperature aroma enhancement treatment. The aroma enhancement process is carried out in stages with variable-temperature control. In the first stage, the aroma is enhanced at 85℃ for 60 minutes; in the second stage, the temperature is raised to 100℃ and the aroma is enhanced for another 30 minutes; in the third stage, the temperature is further raised to 120℃ and the aroma is enhanced for another 8 minutes, resulting in high-quality summer and autumn black tea.

[0074] Sensory evaluation was conducted on the summer and autumn black tea obtained in this embodiment (referring to the national standard GB / T 23776). The results showed that the obtained summer and autumn black tea had tightly rolled leaves, a dark and lustrous color with visible white down, a complex aroma of honey and flowers, a bright and clear red tea liquor, a mellow and refreshing taste with a distinct sweet aftertaste, and bright and evenly red tea leaves. The overall sensory score was 95.4.

[0075] The theaflavins and volatile components of the obtained black tea product were analyzed. The results showed that the total theaflavins content was 0.56%. Among the volatile aroma components, terpenoids and their oxidation products were the main components, with a relative content of 19.32% for terpenoids, 6.03% for phenylethanol, 14.05% for geraniol, and 12.27% for methyl salicylate.

[0076] Further analysis was conducted on the tea polyphenols, total flavonoids, ester-type catechins, and phenol-to-amino acid ratio of the black tea product. The results showed that the tea polyphenol content in the sample was 16.25%, the total flavonoid content was 3.21%, the ester-type catechin content was 5.45%, and the phenol-to-amino acid ratio was 7.21.

[0077] Comparative Example 1: (Traditional Craftsmanship) Mature fresh leaves (one bud and two leaves) harvested in summer were evenly spread in a natural withering shed to a thickness of 3 cm for natural withering. Withering was carried out for 6 hours at an ambient temperature of 30℃ and a relative humidity of 75%. During this period, due to significant environmental fluctuations, the leaves lost water rapidly and unevenly, with some leaves showing edge curling and slight reddening. After withering, the leaf moisture content was 68%, indicating insufficient conversion of aroma precursors.

[0078] The wilted leaves were placed in a rolling machine for conventional rolling. No pressure gradient was set during the rolling process; a constant pressure of 120N was used for 25 minutes. The rolled leaves were then spread flat in a fermentation tray and fermented naturally with ventilation. Temperature, humidity, and oxygen content were not controlled. The environmental conditions were 28℃, 80% relative humidity, and 21% oxygen content, with a fermentation time of 3 hours. The fermented leaves were then dried using a traditional hot air dryer, with the hot air temperature maintained at 95℃, until the moisture content reached 6.5%.

[0079] Sensory evaluation was conducted on the summer and autumn black tea obtained in this comparative example (referring to the national standard GB / T 23776). The results showed that the obtained black tea had coarse and loose leaves, lacked luster, had a weak aroma with obvious grassy and burnt notes, a dark reddish color with insufficient brightness, a rough and astringent taste, weak aftertaste, and dark brown and messy tea leaves. The overall sensory score was 83.2, which was significantly lower than that of the sample in the example.

[0080] The analysis of theaflavins and volatile components in the obtained black tea product showed that the total theaflavin content was 0.32% (the percentages of individual theaflavins were: TF 0.04%, TF-3G 0.06%, TF-3'G 0.03%, and TFDG 0.19%); the relative contents of terpenoids were 12.46%, phenylethanol was 3.15%, geraniol was 7.86%, and methyl salicylate was 6.05%. Overall, the aroma composition was weak and structurally uncoordinated. These findings indicate that the aroma level of summer and autumn black tea processed using traditional methods is significantly low, making it difficult to achieve high-quality products.

[0081] Further analysis was conducted on the tea polyphenols, total flavonoids, ester-type catechins, and phenol-to-amino acid ratio of the black tea product. The results showed that the tea polyphenol content in the sample was 18.26%, the total flavonoid content was 3.89%, the ester-type catechin content was 6.51%, and the phenol-to-amino acid ratio was 8.82.

[0082] The theaflavins content and volatile aroma compounds in all examples and comparative examples in this specification were determined using a unified detection method, and the relevant operating steps are as follows. For ease of explanation, only the detection results of Example 1 and Comparative Example 1 are presented below. Figure 1 and Figure 2 Displayed in the form of [format].

[0083] The theaflavin composition of the black tea samples obtained in Example 1 and Comparative Example 1 was determined by high-performance liquid chromatography (HPLC). 0.5 g of ground tea sample that passed through a 60-mesh sieve was weighed and 25 mL of an extraction solvent prepared from anhydrous ethanol and water at a ratio of 70:30 (v / v) was added. The mixture was ultrasonically extracted at 25°C for 30 min. After centrifuging the extract at 8000 rpm for 10 min, the supernatant was collected and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) membrane. This supernatant was used as the HPLC injection solution. Analysis was performed using a Waters XBridge C18 column (250 mm × 4.6 mm, 5 μm) at a wavelength of 278 nm. Mobile phase A was 0.1% glacial acetic acid aqueous solution, and mobile phase B was acetonitrile. The gradient elution program was as follows: 0–10 min: A:B = 80:20; 11–20 min: A:B = 70:30; 21–30 min: A:B = 60:40; 31–40 min: A:B = 50:50; 41–50 min: A:B = 40:60; 51–60 min: A:B = The concentration ratio was 30:70, the flow rate was 1.0 mL / min, the column temperature was 30℃, the injection volume was 10 μL, and the content of theaflavins (TF), theaflavins-3-gallate (TF-3G), theaflavins-3′-gallate (TF-3′G) and theaflavins digallate (TFDG) was determined by external standard method.

[0084] The test results showed that in the black tea obtained in Example 1, the contents of TF, TF-3G, TF-3′G, and TFDG were 0.07%, 0.10%, 0.05%, and 0.36%, respectively, with a total theaflavins content of 0.58%. In contrast, in the black tea obtained in Comparative Example 1, the contents of TF, TF-3G, TF-3′G, and TFDG were 0.04%, 0.06%, 0.03%, and 0.19%, respectively, with a total theaflavins content of only 0.32%. A comparison chart of the percentage content of theaflavins in the black tea products of Example 1 and Comparative Example 1 was plotted based on the above data. Figure 1 As shown. By Figure 1 It is evident that the tea produced by the process of this invention contains significantly higher levels of various theaflavins than that produced by the traditional process. This indicates that the withering, rolling, fermentation, compound drying, and aroma enhancement control measures of this invention promote the formation of theaflavins and effectively enhance the redness and mellowness of the tea soup.

[0085] Subsequently, volatile aroma compounds were further analyzed in both groups of tea samples. 2g of tea sample was placed in a 20mL headspace vial, 5mL of ultrapure water was added, and the vial was sealed. Equilibration was carried out at 60℃ for 15min, followed by extraction of volatile components using a DVB / CAR / PDMS solid-phase microextraction fiber for 40min. The sample was then analyzed by inserting the vial into the GC-MS inlet for 5min. After separation and identification by GC-MS, the categories and relative contents of each aroma component were confirmed by comparison with the NIST standard spectral library.

[0086] The test results showed that the tea sample obtained in Example 1 contained 19.94% terpenoids, 5.98% phenethyl alcohol, 13.34% geraniol, and 11.67% methyl salicylate, indicating a rich and well-balanced aroma profile. In contrast, the tea sample obtained in Comparative Example 1 contained 12.46% terpenoids, 3.15% phenethyl alcohol, 7.86% geraniol, and 6.05% methyl salicylate, indicating significantly insufficient aroma intensity and balance. A comparison chart of the relative contents of volatile compounds (terpenoids, phenethyl alcohol, geraniol, and methyl salicylate) in the black tea products of Example 1 and Comparative Example 1, based on this data, is shown below. Figure 2 As shown. By Figure 2 It is evident that the tea produced by the process of this invention exhibits significant improvements in multiple key aroma components compared to traditional processes, displaying a higher proportion of floral and fruity aroma substances. This demonstrates that the present invention's strategy of light shaking combined with UV-B-LED combined spectral regulation of withering, low-temperature controlled pressure gradient kneading, three-parameter linkage dynamic fermentation, microwave-hot air coupled drying, and far-infrared variable temperature aroma enhancement can promote the transformation of aroma precursors and the generation of major aromatic substances.

[0087] The results from the combined embodiments and comparative examples show that the novel comprehensive processing technology for summer and autumn black tea proposed in this invention, through the coordinated setting of key processes such as withering, rolling, fermentation, and drying, forms relatively stable and controllable process conditions during processing, which helps to regulate some of the structural characteristics exhibited by summer and autumn tea raw materials during processing. Specifically, spectral-controlled withering provides suitable conditions for the formation and transformation of aromatic precursors and helps improve the uniformity of water loss during withering; pressure gradient rolling makes the cell breakage process of tea leaves more gradual, which is conducive to the gradual release of substrates; three-parameter linked dynamic fermentation improves the consistency of the fermentation environment through the coordinated control of temperature, humidity, and oxygen content; far-infrared aroma enhancement and related drying methods help reduce the loss of aroma substances during processing and improve the stability of the dried tea quality.

[0088] Through the synergistic regulation of these process parameters, the summer and autumn black tea obtained by this invention has significantly higher levels of theaflavins and key aroma substances than that obtained by traditional processing techniques. The aroma is more fragrant, the tea soup is brighter red, and the taste is more mellow and refreshing, resulting in a significant improvement in overall quality. This demonstrates that the technical solution of this invention has significant technological advancements and broad application value.

[0089] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A novel comprehensive processing technique for improving the quality of summer and autumn black tea, characterized in that, It includes the following steps: 1) Gentle shaking combined with UV-B-LED spectral regulation of withering: Summer and autumn tea leaves are spread out in an environment with a wavelength of 450-600 nm and a photosynthetic photon flux density of... Withering is carried out under LED light source; when the moisture content of fresh tea leaves drops to 68-73%, UV-B irradiation with a wavelength of 280-320nm and an intensity of 15-25μW / cm² is applied to the withered leaves. During the UV-B irradiation, the oolong tea light shaking process is introduced simultaneously, and the leaves are shaken once every two hours for a total of four times. The first shaking lasts for 2-4 minutes, the second for 4-6 minutes, the third for 8-12 minutes, and the fourth for 18-22 minutes, so that the moisture content of fresh tea leaves drops to 58-63%. 2) Low-temperature controlled pressure gradient rolling: The withered leaves are rolled in three stages: low pressure, medium pressure and high pressure, and the rolling environment temperature is controlled at 20~25℃. 3) Three-parameter linkage dynamic fermentation: The kneaded leaves are dynamically fermented under the conditions of temperature of 25~30℃, relative humidity of 85~95%, and oxygen content of 21~35%; 4) Microwave-hot air coupled drying: First, microwave heating is used to pre-dry the fermented leaves, reducing the moisture content of the tea to 15-25%. Then, the pre-dried tea is spread out to cool for 40-60 minutes, and then box-type hot air drying is used to reduce the moisture content of the tea to 4-6%. 5) Far-infrared temperature-controlled aroma enhancement: Far-infrared heating is used to enhance the aroma of tea leaves, and temperature control is implemented in stages during the aroma enhancement process to obtain high-quality summer and autumn black tea. The phased temperature control is as follows: First stage: enhance the aroma of tea leaves at 80~90℃ for 50~70 minutes; Second stage: raise the temperature to 95~105℃ and continue to enhance the aroma for 20~40 minutes; Third stage: further raise the temperature to 115~125℃ and enhance the aroma for 5~10 minutes.

2. The new integrated control processing technology according to claim 1, characterized in that, Step 1) The fresh tea leaves mentioned are mature fresh leaves with one bud and two leaves or one bud and three leaves, picked in summer or autumn.

3. The new integrated control processing technology according to claim 2, characterized in that, Step 1) The withering temperature is 22~28℃ and the relative humidity is 50~70%.

4. The new integrated control processing technology according to claim 2 or 3, characterized in that, Step 1) The thickness of the spread material is 2-4cm, and it is turned over 2-3 times during the spreading process.

5. The new integrated control processing technology according to claim 4, characterized in that, Step 2) The force of low-pressure kneading is 50~70N, the force of medium-pressure kneading is 80~100N, and the force of high-pressure kneading is 120~150N.

6. The new integrated control processing technology according to claim 5, characterized in that, Step 2) The total kneading time is 45~60min, of which the time ratio of low pressure, medium pressure and high pressure kneading is 2~3:2~4:2~3.

7. The new integrated control processing technology according to claim 6, characterized in that, Step 3) The thickness of the leaf spread during dynamic fermentation is 6-8 cm.

8. The new integrated control processing technology according to claim 7, characterized in that, Step 3) The total time for dynamic fermentation is 2-4 hours. During the dynamic fermentation process, the kneading leaves are turned over every 45-70 minutes, and each turning lasts for 2-4 minutes.

9. The new integrated control processing technology according to claim 7 or 8, characterized in that, Step 4) The microwave heating temperature is 105~115℃, the power is 400~600W, and the time is 8~10min.

10. The novel integrated control processing technology according to claim 9, characterized in that, Step 4) The temperature of the box-type hot air drying is 85~95℃, and the time is 30~50min.

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