A processing method for accelerating the aging rate of black tea

Abstract

This invention relates to a processing method for accelerating the aging rate of dark tea. The method involves controlling the moisture content of fresh dark tea leaves to maintain a preset leaf-to-water ratio; employing a preset fixation method at a set temperature; lightly kneading the fixation-treated leaves to smooth the tea strips and control the degree of cell breakage; subjecting the kneaded leaves to a variable-temperature pile fermentation process, adjusting the pile temperature at different stages to control the dominant microbial flora and metabolic activity, promoting the generation and accumulation of dicarbonyl compounds; and finally, drying the fermented leaves at a preset temperature and time to control the final moisture content, thus completing the processing. This invention enhances the endogenous generation and accumulation of dicarbonyl compounds during dark tea processing, significantly accelerating the aging rate of dark tea, enabling new tea to acquire quality characteristics close to those of teas that have undergone several years of natural aging in a shorter period. The generation of key chemical markers for aging is controllable, quantifiable, and repeatable.

Description

Technical Field

[0001] This invention relates to the technical field of manufacturing, preparing or brewing tea and its substitutes, and particularly to a processing method for accelerating the aging rate of dark tea. Background Technology

[0002] Dark tea, one of the six major tea categories, gets its name from its black appearance. Its post-fermentation process is key to its core technical characteristics and quality formation. During aging, the quality of dark tea shows a significant positive improvement; "the older, the more fragrant" is its typical characteristic. As aging time increases, the characteristic astringency and fermentation-related off-flavors of new tea gradually fade. Stimulating substances such as tea polyphenols decompose and transform, while the content of characteristic components such as thearubigins and theaflavins increases significantly. The tea soup changes from cloudy to bright red and clear, the taste changes from rough and astringent to mellow and sweet, and the aroma develops complex aged fragrances such as jujube and wood. The appearance becomes increasingly warm and lustrous, and the overall quality is systematically optimized. The research and application of advanced aging technologies can effectively shorten the aging cycle and reduce storage losses.

[0003] In conclusion, based on the current development status of the dark tea industry, the quality of the aging process, and the practical needs of current aging technologies, there is an urgent need to develop a technical method that can quickly and closely match the characteristics of natural aging and significantly improve the aging rate of dark tea, so as to provide technical support for the high-quality development of the dark tea industry. Summary of the Invention

[0004] This invention solves the problems existing in the prior art and provides a processing method to accelerate the aging rate of dark tea. By adjusting the total amount of characteristic compounds during the processing, the speed of dark tea aging can be controlled.

[0005] The technical solution adopted in this invention is a processing method for accelerating the aging rate of dark tea, comprising the following steps:

[0006] S1 controls the moisture content of fresh black tea leaves to keep the ratio of fresh leaves to water within a preset range.

[0007] S2 uses a preset blanching method and performs blanching treatment at a set temperature;

[0008] S3 involves (light) kneading of the blanched leaves to smooth the tea strips and control the degree of cell breakage.

[0009] S4 involves a variable-temperature pile fermentation process on the rolled leaves to regulate the pile temperature at different stages, thereby controlling the dominant microbial flora and metabolic activity, and promoting the formation and accumulation of dicarbonyl compounds. The variable-temperature pile fermentation process comprises three sequential stages: Phase 1: Control the pile temperature at 28-32℃, and use the first type of dominant bacteria to release glycoside hydrolytic enzymes to promote the hydrolysis of endogenous polysaccharides in tea leaves; The second stage involves controlling the pile temperature at 35–38°C and utilizing the oxidase secreted by the second type of dominant microbial species to accelerate the generation of dicarbonyl compounds. Third stage: Control the pile temperature at 38-40℃ to promote the accumulation of dicarbonyl compounds; during the third stage, continuously monitor the total amount of dicarbonyl compounds in the pile leaves, and terminate the pile fermentation when the total amount exceeds the preset threshold; otherwise, extend the third stage until the threshold is reached.

[0010] S5 performs a pre-set temperature and duration drying process on the fermented leaves to control the final moisture content and complete the processing.

[0011] Preferably, in S1, the ratio of fresh black tea leaves to water is no higher than 5:1; the fresh leaves and water are mixed and left to stand, and the mixture is turned over periodically during the standing period until the tea leaves reach the preset shape.

[0012] Preferably, S2 uses drum blanching, with the temperature set at 280~300℃. After blanching, the moisture content of the raw material is 58%~62%, and the raw material is directly piled up after blanching (without cooling) to avoid rapid cooling.

[0013] Preferably, in step S3, the kneading pressure is adjusted in stages, and the total kneading time is 18~22 minutes.

[0014] Preferably, the total amount of the dicarbonyl compound is monitored by fluorescence derivatization; o-phenylenediamine is used as the derivatization reagent to generate quinoxaline derivatives under acidic conditions, the fluorescence intensity is detected by fluorescence spectrophotometry, and a standard curve is established using 2-methylquinoxaline as a standard for quantification, and the results are expressed as acetone aldehyde equivalents.

[0015] Preferably, the excitation wavelength of the fluorescence spectrophotometer is 290 nm, the emission wavelength is 400 nm, and both the excitation slit and the emission slit are 5 nm.

[0016] Preferably, the first category of dominant microbial species includes Rhizopus, yeast, and Penicillium, and the second category of dominant microbial species includes Aspergillus niger, yeast, and lactic acid bacteria.

[0017] Preferably, in step S5, the moisture content after drying is 10% to 14%.

[0018] This invention relates to a processing method for accelerating the aging rate of dark tea. The method involves controlling the moisture content of fresh dark tea leaves to maintain a preset leaf-to-water ratio within a predetermined range; employing a preset fixation method at a set temperature; lightly kneading the fixation-treated leaves to smooth the tea strips and control cell breakage; subjecting the kneaded leaves to variable-temperature pile fermentation to regulate the pile temperature at different stages, controlling the dominant microbial flora and metabolic activity, and promoting the generation and accumulation of dicarbonyl compounds; and finally, drying the fermented leaves at a preset temperature and duration to control the final moisture content, thus completing the processing.

[0019] The beneficial effects of this invention are as follows:

[0020] (1) Through the synergistic effect of fresh leaf moisture regulation, high temperature fixation, light rolling, variable temperature piling and high temperature short-time drying, the endogenous generation and accumulation of dicarbonyl compounds in the processing of black tea are enhanced, thereby significantly accelerating the aging rate of black tea in the subsequent storage process, so that the new tea can obtain quality characteristics close to those of natural aging for several years in a short period of time.

[0021] (2) By controlling the pile temperature in stages and regulating the dominant microbial community and its metabolic activity in a targeted manner, the timing optimization of polysaccharide hydrolysis and dicarbonyl compound generation is achieved, breaking through the limitations of traditional pile fermentation that relies on experience judgment, and making the generation of key chemical markers of aging controllable, quantifiable and repeatable.

[0022] (3) Make full use of the effects of humid heat, residual activity of endogenous enzymes and the pre-culture effect of microorganisms to form a whole-chain accelerated aging technology system from fresh leaves to primary tea. Compared with traditional black tea processing, the time required for black tea to reach the same aging quality can be greatly shortened.

[0023] (4) Provide the black tea industry with an efficient and standardized accelerated aging technology solution that conforms to the natural aging characteristics; the black tea prepared by the method of this invention has a bright red color, mellow and sweet taste, and significant aged aroma. Its quality is superior to that of conventional new tea, and the rate of quality improvement during the aging process is controllable. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating the processing of the present invention;

[0025] Figure 2 This is a schematic diagram illustrating the temperature changes during the pile fermentation process in this invention.

[0026] Figure 3 This is a schematic diagram illustrating the change in the content of dicarbonyl compounds with storage time during the experiment of this invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] This invention relates to a processing method for accelerating the aging rate of dark tea, comprising the following steps:

[0029] S1 controls the moisture content of fresh black tea leaves to keep the ratio of fresh leaves to water within a preset range.

[0030] S2 uses a preset blanching method and performs blanching treatment at a set temperature;

[0031] S3 involves kneading the withered leaves to smooth the tea strips and control the degree of cell breakage;

[0032] S4 involves variable-temperature pile treatment of the rolled leaves to regulate the pile temperature at different stages, thereby controlling the dominant microbial population and metabolic activity, and promoting the generation and accumulation of dicarbonyl compounds.

[0033] S5 performs a pre-set temperature and duration drying process on the fermented leaves to control the final moisture content and complete the processing.

[0034] The following description is based on specific embodiments.

[0035] It should be noted that the dicarbonyl compounds mentioned in this invention mainly refer to α-dicarbonyl compounds such as glyoxal (GO), acetone aldehyde (MGO), and 3-deoxyglucuronide (3-DG), and their content changes are closely related to the aging rate of dark tea.

[0036] S1 Moisture Regulation

[0037] In S1, the ratio of fresh black tea leaves to water is no higher than 5:1; mix the fresh leaves with water and let them stand, turning them regularly during the standing period until the tea leaves reach the preset shape.

[0038] Specifically, the harvested fresh black tea leaves are piled with drinking water at a ratio not exceeding 5:1. In this embodiment, 100 kg of fresh leaves are taken and 20 kg of drinking water is added (ratio 5:1). After being thoroughly mixed, the mixture is left to stand for 3 hours. During the standing process, the tea leaves are turned over every half hour to prevent the tea leaves from piling up and generating heat. The preset shape refers to the tea leaves and tea strips being naturally stretched and upright (without wilting) after being fully stood, with no obvious water droplets on the surface of the tea strips.

[0039] S2 filming wrapped

[0040] S2 uses a drum blanching process with a temperature set at 300℃. After blanching, the moisture content of the raw materials is 58%~62%, and they are piled up directly after blanching to avoid rapid cooling.

[0041] Specifically, the temperature of the drum blanching machine is set at 300℃, the leaf temperature is detected at around 120℃, and the blanching time is about 100~120 seconds. After blanching, the moisture content of the raw material is about 62%, the leaves are sticky and not easy to break. After blanching, the leaves are immediately piled up (the leaves are piled up in a concentrated manner) to a height of about 30cm to avoid spreading them out to cool down and allow the leaves to cool down naturally (to room temperature).

[0042] S3 (Light) Kneading

[0043] In S3, the kneading pressure is adjusted in stages, and the total kneading time is 18~22 minutes.

[0044] Specifically, a 55 or 65 type rolling machine is selected. In this embodiment, a 65 type rolling machine is used, with a leaf loading capacity of approximately 40 kg. The leaves, after being killed, are placed into the rolling machine while still hot, filling the rolling drum naturally. The pressure control of the rolling machine requires the machine lid to be just above the tea leaves. The pressure is adjusted every 5 minutes according to the rolling process (starting with light pressure and gradually increasing it). For example, in this embodiment, the pressure is initially at rest (only the weight of the machine lid) for 0-5 minutes, increased by 3 cm for 5-10 minutes, increased by 5 cm for 10-15 minutes, and reduced to rest for 15-20 minutes. The total rolling time is controlled at around 20 minutes (e.g., 18 minutes, 20 minutes, 22 minutes). If the rolling time is too long, the temperature will drop, increasing breakage and making it difficult to keep the leaves intact. If the rolling time is too short, the leaves will not be properly shaped. After rolling, the tea strips are tightly rolled into strips, and the cell breakage rate is controlled within 30%. Less cell breakage can effectively prevent the combination of tea polyphenols and dicarbonyl compounds through nucleophilic substitution reactions, reducing unnecessary internal losses of dicarbonyl compounds.

[0045] S4 Variable Temperature Fertilizer

[0046] In S4, the variable-temperature ignition process consists of three sequentially performed stages, including:

[0047] Phase 1 (Low-Temperature Start-up): The pile temperature is controlled at 28–32℃. The first type of dominant microorganisms release glycoside hydrolases to promote the hydrolysis of endogenous polysaccharides in tea. The first type of dominant microorganisms include Rhizopus, Yeast, and Penicillium. The key enzyme activities are glycoside hydrolases, including amylase, pectinase, and tanninase, with peak values ​​of 28.6–36.2 U / g.

[0048] The second stage (medium-temperature enrichment period): The pile temperature is controlled at 35-38℃, and the oxidase secreted by the second type of dominant microorganisms is used to accelerate the generation of dicarbonyl compounds. The second type of dominant microorganisms include Aspergillus niger, yeast, and lactic acid bacteria. The key enzyme activity is oxidase / polyphenol oxidase (PPO), with a peak value of 41.5-49.3 U / g, and also includes a small amount of tanninase.

[0049] The third stage (stable temperature maintenance period): The reactor temperature is controlled at 38-40℃ to promote the accumulation of dicarbonyl compounds. At this time, the dominant microbial species are Bacillus, thermophilic filamentous fungi, yeast, and a small amount of Aspergillus niger. The rest are microorganisms. The key enzyme activity is a complex hydrolytic enzyme, including cellulase, protease, lipase, etc. The peak value of cellulase is 30.1-35.8 U / g. It also includes protease, with a peak value of 22.4-28.7 U / g.

[0050] In the first stage, the activity of glycoside hydrolase reaches its peak, promoting the hydrolysis of polysaccharides into monosaccharides, providing precursors for the subsequent formation of dicarbonyl compounds; in the second stage, the activity of polyphenol oxidase reaches its peak, accelerating the formation of dicarbonyl compounds; in the third stage, the complex hydrolase maintains high activity, ensuring the continuous accumulation of dicarbonyl compounds.

[0051] In this embodiment, approximately 50 kg of rolled leaves are evenly spread on the fermentation equipment. The thickness of the pile during the fermentation process does not exceed 30 cm to ensure that the temperature inside and outside the pile is as uniform as possible. Temperature control is achieved by real-time monitoring using temperature and humidity sensors. The temperature is maintained at 30℃±2℃ for 8 hours through turning or ventilation. During this period, Rhizopus and yeast are detected as the dominant bacteria. In the second stage, the temperature is raised to 36℃±2℃ for 10 hours, during which Aspergillus niger and lactic acid bacteria multiply in large quantities. In the third stage, the temperature is raised to 39℃±1℃ for 6 hours.

[0052] In the third stage, higher temperatures are used to accelerate the action of microorganisms and promote the formation of dicarbonyl compounds. The total amount of dicarbonyl compounds in the fermented leaves is continuously monitored. When the total amount exceeds a preset threshold, the fermentation process is terminated; otherwise, the third stage is extended until the threshold is reached. In specific implementation, the total amount of dicarbonyl compounds is continuously monitored during the fermentation process. When the detected value reaches 30 μg / g (which may be slightly higher), the drying process can begin. During the drying process, high-temperature roasting further promotes the formation of dicarbonyl compounds, and the final finished tea contains more than 40 μg / g. In this embodiment, the total amount of dicarbonyl compounds was 18 μg / g when the sampling and testing began. Fermentation continued until the 24th hour, when the detected value was 31 μg / g, and the fermentation process was terminated.

[0053] S5 drying

[0054] In S5, the drying process uses a high-temperature, short-time method; after drying, the moisture content is 10%~14%.

[0055] Specifically, a combination of roasting and hot air drying is used. The roasting temperature is 240-260℃, which rapidly inactivates enzymes, kills microorganisms, and stops the piling process. The radiant heat from the roasting acts on the tea leaves from both inside and outside, further breaking down glycosidic bonds to create conditions for the formation of dicarbonyl compounds, while also promoting Maillard reactions and accelerating dicarbonyl formation. The leaf pile is 2-3cm thick, and the drying time is about 45 seconds, reducing the moisture content to about 40%. Then, hot air drying is used at a temperature of 90-105℃, with the leaf pile thickness being 3-5cm, for about 35-40 minutes, reducing the moisture content to about 10-14% (this moisture content creates conditions for the subsequent reaction and transformation of dicarbonyl with amino acids, tea polyphenols, and other substances, accelerating the aging of dark tea), and the moisture content meets the standards.

[0056] The dried tea leaves are the initial processed products of black tea that are accelerated to age. The content of dicarbonyl compounds is retained at more than 40μg / g. Under normal storage conditions, they can quickly exhibit aging characteristics such as aged aroma and bright red liquor.

[0057] The drying process employs a combination of roasting, heating, and air drying belts. This step utilizes high temperature to promote the Maillard reaction and glycosidic bond cleavage, creating conditions for the formation of dicarbonyl compounds. After drying, the moisture content is 10%~14%.

[0058] In this embodiment, the total amount of dicarbonyl compounds is controlled at approximately 40 μg / g (based on acetone aldehyde equivalent). In this invention, when the dicarbonyl compound content is below 25 μg / g (based on acetone aldehyde equivalent), the subsequent aging rate is slow; when the content reaches 40 μg / g or higher, the rate of aroma formation is significantly accelerated, and the sensory score after 6 months of storage is significantly better than the low-content group; further increasing to above 55 μg / g results in a gradual increase in the aging rate, and the tea is prone to over-aging. Considering both aging efficiency and quality controllability, this invention sets the content at 40 μg / g.

[0059] In this invention, the total amount of dicarbonyl compounds can be monitored using the following methods, but is not limited to them: a fluorescence derivatization method is used, with o-phenylenediamine as the derivatization reagent, to react under acidic conditions to generate quinoxaline derivatives, the fluorescence intensity is detected by fluorescence spectrophotometry, and a standard curve is established using 2-methylquinoxaline as a standard for quantification, with the results expressed as acetone aldehyde equivalents.

[0060] Specifically, samples of *Pyrus pyrifolia* leaves were freeze-dried, pulverized, and extracted with 0.1% v / v glacial acetic acid aqueous solution. Carrez I and Carrez II reagents were added to precipitate proteins, and the supernatant was collected after low-temperature centrifugation. Using o-phenylenediamine as a derivatizing reagent, it reacted with α-dicarbonyl compounds in the extract under acidic conditions to generate quinoxaline derivatives (reaction at room temperature in the dark for 24 hours). The excitation wavelength of the fluorescence spectrophotometer was 290 nm, the emission wavelength was 400 nm, and both the excitation and emission slits were 5 nm. A standard curve was established using 2-methylquinoxaline as a standard, and the results are expressed as acetone aldehyde equivalents (μg / g).

[0061] To verify the accelerated aging effect of the method of the present invention, the following comparative experiment was conducted.

[0062] Experiment 1

[0063] Experimental materials: The same batch of fresh black tea leaves were divided into two groups; the experimental group was processed using the method of the present invention; the control group was processed using the traditional black tea processing method (natural fermentation, temperature not actively controlled, fermentation time of about 15 days, and moisture content controlled at about 12% after drying).

[0064] Testing indicators: After the new tea is processed and stored at room temperature in the dark for 3 months, 6 months and 12 months, the total amount of dicarbonyl compounds (fluorescence derivatization method) and sensory quality scores (conducted by a professional evaluation team according to national standards, such as GB / T23776-2018 Sensory Evaluation Method for Tea) are determined.

[0065] The experimental results are shown in Table 1 below;

[0066] Table 1 Experimental Results

[0067]

[0068] Note: The data is the mean of three repeated experiments.

[0069] The content of dicarbonyl compounds in the experimental group of new tea was 45 μg / g, which was higher than 31 μg / g at the end of the pile fermentation. This was mainly attributed to the continued occurrence of Maillard reaction and thermal cleavage of glycosidic bonds during the subsequent high-temperature roasting and drying process, which further generated some dicarbonyl compounds.

[0070] Experiment 2

[0071] Experimental materials: The same batch of fresh dark tea leaves were used. The fermentation process was divided into experimental group and control group 1-3. The experimental group was processed using the method of the present invention (stepwise temperature increase: 28→35→38℃). Control group 1 was fermented at a constant temperature of 35℃. The fermentation temperature of control group 2 was first high and then low (50→40→30℃). Other process conditions were the same as those of the present invention. Control group 3 was processed using the traditional dark tea processing method (natural fermentation, temperature not actively controlled, and moisture content controlled at about 12% after drying).

[0072] The detection indicators are the same as those in Experiment 1.

[0073] The experimental results are shown in Table 2 below;

[0074] Table 2 Experimental Results

[0075] experimental group 45 83 88 92 Control group 1 33 72 73 73 Control group 2 23 68 70 71 Control group 3 25 75 75 76

[0076] This further verifies the beneficial effects of the method of the present invention.

[0077] Experiment 3

[0078] Experimental materials: The same batch of fresh black tea leaves were processed using different techniques to achieve several levels of dicarbonyl compound content in the finished tea, including less than 25 μg / g, 25~40 μg / g, 40~55 μg / g, and greater than 55 μg / g.

[0079] Testing indicators: Sensory quality scores and liquor color evaluations were conducted after the new tea was processed and after it was stored at room temperature in the dark for 3 months, 6 months, and 12 months.

[0080] The experimental results are shown in Table 3 below;

[0081] Table 3 Experimental Results

[0082] <25 78 82 83 Huang Liang Yellow Orange Yellow Orange 25～40 80 85 86 Huang Liang Yellow Orange Yellow orange with red 40～55 85 88 92 Yellow Orange Yellow orange with red Yellow and red >55 88 92 95 Yellow Orange Yellow and red Bright red

[0083] In summary, the results in Table 3 further validate the dose-effect relationship between the content of dicarbonyl compounds and the aging quality of dark tea. With increasing dicarbonyl compound content, both the aroma score and the brightness of the tea liquor during storage showed an upward trend. When the dicarbonyl compound content was below 25 μg / g, the aroma score after 12 months of storage was only 83 points, and the liquor color was yellow-orange, indicating a slow aging process. When the content was between 25 and 40 μg / g, the score rose to 86 points after 12 months of storage, and the liquor color turned yellow-orange with red, showing some improvement in aging effect, but still not significant. When the content reached 40–55 μg / g, the score reached 92 points after 12 months of storage, and the liquor color was yellow-red, indicating a significant improvement in aroma quality. Further increasing the content to above 55 μg / g, the score reached 95 points after 12 months of storage, but the increase tended to level off. The above results show that controlling the content of dicarbonyl compounds within the range of 40–55 μg / g can ensure aging quality while taking into account process efficiency and economy, further confirming the rationality and technical advantages of using 40 μg / g as the target control value in this invention.

[0084] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0085] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A processing method for accelerating the aging rate of dark tea, characterized in that, Includes the following steps: S1 controls the moisture content of fresh black tea leaves to keep the ratio of fresh leaves to water within a preset range. S2 uses a preset blanching method and performs blanching treatment at a set temperature; S3 involves kneading the blanched leaves to smooth the tea strips and control the degree of cell breakage. S4 involves variable-temperature pile treatment of the rolled leaves to regulate the pile temperature at different stages, thereby controlling the dominant microbial population and metabolic activity, and promoting the generation and accumulation of dicarbonyl compounds. The variable-temperature ignition process consists of three sequentially performed stages, including: Phase 1: Control the pile temperature at 28-32℃, and use the first type of dominant bacteria to release glycoside hydrolytic enzymes to promote the hydrolysis of endogenous polysaccharides in tea leaves; The second stage involves controlling the pile temperature at 35–38°C and utilizing the oxidase secreted by the second type of dominant microbial species to accelerate the generation of dicarbonyl compounds. Third stage: Control the pile temperature at 38-40℃ to promote the accumulation of dicarbonyl compounds; during the third stage, continuously monitor the total amount of dicarbonyl compounds in the pile leaves, and terminate the pile fermentation when the total amount exceeds the preset threshold; otherwise, extend the third stage until the threshold is reached. S5 performs a pre-set temperature and duration drying process on the fermented leaves to control the final moisture content and complete the processing.

2. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, In S1, the ratio of fresh black tea leaves to water is no higher than 5:1; mix the fresh leaves with water and let them stand, turning them regularly during the standing period until the tea leaves reach the preset shape.

3. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, S2 uses drum blanching with a temperature set at 280~300℃. After blanching, the moisture content of the raw materials is 58%~62%, and they are directly piled up after blanching.

4. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, In S3, the kneading pressure is adjusted in stages, and the total kneading time is 18~22 minutes.

5. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, The total amount of the dicarbonyl compounds was monitored using a fluorescence derivatization method. o-phenylenediamine was used as the derivatization reagent to generate quinoxaline derivatives under acidic conditions. The fluorescence intensity was detected by fluorescence spectrophotometry, and a standard curve was established using 2-methylquinoxaline as a standard for quantification. The results were expressed as acetone aldehyde equivalents.

6. The processing method for accelerating the aging rate of dark tea according to claim 5, characterized in that, The excitation wavelength of the fluorescence spectrophotometer is 290 nm, the emission wavelength is 400 nm, and both the excitation slit and the emission slit are 5 nm.

7. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, The first category of dominant microorganisms includes Rhizopus, yeast, and Penicillium, while the second category includes Aspergillus niger, yeast, and lactic acid bacteria.

8. The processing method for accelerating the aging rate of dark tea according to claim 1, characterized in that, In S5, after drying, the moisture content is 10%~14%.

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