Ecological oxidation processing method of oolong tea

Abstract

The invention discloses an ecological oxidation processing method of oolong tea, which takes the ratio of free water / bound water of tea green cells as a key index and runs through the stages of fine manipulation, fixation and drying. By manually simulating the northeast wind climate environment and combining the synergistic effect of chloroplast, vacuoles and mitochondria, aerobic respiration and tricarboxylic acid circulation of tea leaves are restarted and maintained, and accumulation and transformation of contained substances are promoted. According to the method disclosed by the invention, the quality of the tea leaves is remarkably improved, the finished tea soup is fragrant, clear, sweet and active, the flavor is harmonious, the tea soup is neutral and slightly alkaline, the tea soup has stable flower and fruit fragrance, and a brand-new theoretical view angle and a practical path are provided for tea leaf processing.

Description

Technical Field

[0001] This invention relates to the field of tea processing, and in particular to an ecological oxidation processing method for oolong tea. Background Technology

[0002] Oolong tea is a unique type of tea in my country, and its traditional processing is complex, with the core being the fermentation (or oxidation) process during the "making green" stage. Currently, the degree of "making green" largely relies on the experience of tea masters, who judge by observing the shape of the tea leaves and smelling changes in aroma. This method suffers from problems such as poor batch stability, significant susceptibility to climate influences, and noticeable quality fluctuations.

[0003] Furthermore, traditionally processed oolong tea often has a neutral to slightly acidic flavor, while consumers have higher demands for the harmony of tea flavor, the persistence of aroma (carrying fragrance into the water), and the comfort after drinking (such as the acidity or alkalinity of the tea soup). Therefore, there is an urgent need for a processing method that can be stable, controllable, and significantly improve the intrinsic quality of tea. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an ecological oxidation processing method and product for oolong tea. This invention starts by restoring and maintaining the life activities of detached tea leaves, using continuous moisture replenishment and the free water / bound water ratio as core control indicators. Through precise control of process conditions, it achieves efficient and coordinated transformation of the substances contained in the tea leaves, ultimately yielding high-quality oolong tea with a unique flavor, stable quality, and a neutral to slightly alkaline tea liquor.

[0005] The present invention provides the following technical solution:

[0006] An ecological oxidation processing method for oolong tea includes the following steps:

[0007] a) Picking tea leaves;

[0008] Before processing, it is necessary to determine the number of times to shake the tea leaves to achieve the goal of shaking the leaves three times to awaken, nourish, and strengthen them.

[0009] Establish measures to be taken in the tea-making process, and balance between natural forces (including natural phenomena such as oxidation and the inherent laws of tea leaves) and human forces (including tea-making process procedures).

[0010] b) Sun-drying and opening: Sun-dry the tea leaves in the sun. During this process, two people need to work together to continuously turn and spread them out. Afterward, move them indoors to cool and open for 3-6 minutes.

[0011] c) Withering and processing: After step b) withering, place the tea leaves in an artificial climate withering room for the first shaking, let them stand for a period of time, then shake them a second time. After the second shaking is completed, shake them a third time, and let them stand and wither during the shaking intervals.

[0012] In this step, the tea leaves enter the tricarboxylic acid cycle and work with the mitochondria to complete the first withering process in 2 hours. This process serves to awaken the tea leaves. A second shaking is then performed, followed by a second withering in the withering room, which lasts for 2 hours to complete the "resting" process. Then, a third shaking is performed, and the leaves are returned to the withering room for further withering. This process takes 6-8 hours, sometimes up to 10 hours, depending on the tea leaves' viability and water saturation.

[0013] d) Fixation: When the free water / bound water ratio of the tea leaves from step c) is close to or tends to 1, fixation is carried out at 320-350℃.

[0014] e) Rolling and drying: The leaves are rolled several times to adjust the overall material balance of the tea leaves, so that the squeezed water can be reintegrated and absorbed, so that the tea soup tastes uniform, and then dried.

[0015] f) Roasting: After storing the dried tea leaves for six months to a year, roast them at 65℃ to 120℃ according to the target aroma.

[0016] Furthermore, the tea leaves picked in step a) are tea leaves with stems, consisting of one bud and two to three leaves, and with small to medium opening.

[0017] Furthermore, the ambient temperature of the artificial climate withering room described in step c) is controlled at 20-22℃, with the airflow flowing clockwise to maintain the internal temperature of the tea leaves at 35-37℃.

[0018] Furthermore, the specific operation of roasting described in step e) is as follows;

[0019] If only the aroma of the tea needs to be restored, it only needs to be roasted at 65℃ for 4-6 hours;

[0020] To achieve a rich, caramelized aroma, roast the tea at 80℃ for 4-6 hours, and then at 120℃ for 2-3 hours, after restoring the tea's fragrance.

[0021] Based on the same inventive concept, this invention also provides oolong tea prepared by the ecological oxidation processing method of oolong tea, wherein the oolong tea has a pH of 7-7.5 and has floral and fruity aromas and three flavors: sweet, salty, and bitter.

[0022] The beneficial effects achieved by this invention are as follows:

[0023] This invention uses the ratio of free water to bound water in tea leaves as a key indicator throughout the withering, fixation, and drying stages. By artificially simulating the northeasterly wind climate environment and combining the synergistic effects of chloroplasts, vacuoles, and mitochondria, it restarts and maintains aerobic respiration and the tricarboxylic acid cycle in tea leaves, promoting the accumulation and transformation of internal substances. This method significantly improves tea quality, resulting in a finished tea liquor that is "fragrant, clear, sweet, and lively," with a harmonious flavor, a slightly alkaline pH, and a stable floral and fruity aroma. It provides a completely new theoretical perspective and practical approach for tea processing. Detailed Implementation

[0024] 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 in conjunction with the embodiments of the present invention. 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.

[0025] Example 1:

[0026] Harvesting: On sunny days from 8 am to 4 pm, one bud and two to three leaves are picked in the Datian Tieguanyin tea garden in Sanming, Fujian. The tea leaves are small to medium-sized and have a high organic content in the tea stems, which is conducive to the transport of nutrients and lays the foundation for subsequent processing.

[0027] Sun-drying and withering: The tea leaves are thinly spread on a cloth. Two people work together to spread and turn the leaves repeatedly. Because the midday sun is strongest, the pigments absorb light energy quickly, and body temperature rises rapidly. Turning helps cool the tea and awaken it. The process continues until the leaves turn a light green, are not too soft, and have a slight grassy smell. Immediately move the tea to the withering room for 6 minutes. At this point, unlike the traditional method which focuses on aroma, the ecological process has a different understanding. The shaking action changes: ① It restores stem pressure and water transport capacity, cools the tea, and transports nutrients; ② The stem pressure and transpiration pull create a reaction force, restraining excessive transpiration from the leaf surface and changing the "water removal" method. The ecological process removes water through gas, thus restoring ecological conditions—a technological breakthrough. If the withering process is stopped and the tea is simply placed in the withering room, awakening the tea is meaningless and may even damage the cells.

[0028] Withering: After the initial processing, the tea leaves are placed in an artificial climate withering room (temperature 21℃~22℃). The air conditioning only cools, not dehumidifies; water removal must be natural, and the water level must be kept saturated – a concept different from traditional methods. This is also an innovation; the ratio of free water to bound water controls the degree of shaking, primarily regulating heat resistance.

[0029] In a simulated northeasterly wind environment, the first shaking lasts 3-6 minutes (6 minutes is preferred if the tea has been sufficiently awakened). The core function of this stage is to restore the stem pressure of the tea leaves after they are removed from the plant through mechanical energy, initiate the water cycle (water molecule metabolism), and create conditions for chloroplasts to carry out photolysis of water, sugar reduction, and aerobic respiration. About 2 hours after the first shaking (the time required for one cycle of the tricarboxylic acid cycle), the second shaking is performed. The shaking time is adjusted according to the state of the tea leaves: 7-9 minutes for morning and afternoon shaking, and 9-11 minutes for evening shaking. If the tea leaves are whitish and weak, the shaking time is shortened to 5-6 minutes, focusing on "nourishing the leaves." Then, a third shaking is performed: 16-20 minutes for morning and afternoon shaking, and 20-24 minutes for evening shaking. This improves cell vitality, increases the number of tricarboxylic acid cycles, promotes the accumulation of organic matter and its transfer to vacuolar storage, and fully nourishes the tea leaves.

[0030] The aforementioned withering and processing are carried out in a dedicated withering room, with the temperature controlled at 20-22℃ (not 18℃) to create a temperature difference between the inside and outside of the tea leaves, maintaining the optimal cell vitality and transpiration pull of the tea leaves at an internal temperature of 37℃. An air conditioning system generates a clockwise airflow facing south (the tea leaves are most vigorous in the first half of the night, resulting in rapid moisture loss; the cool, moist airflow from the north in the second half of the night slows down moisture loss, playing a role in moisture retention, which is crucial for the softness, delicacy, and freshness of the tea soup). This simulates the dry and cool climate of the northeast wind, maintaining the optimal physiological state of the tea leaves at 37℃. Based on the cooling and drying characteristics of the northeast wind, the air conditioning system regulates temperature and humidity, simulating an ideal air pressure gradient to enhance leaf transpiration pull and water molecule participation.

[0031] When the ratio of free water to bound water is greater than 1 and tends to be 1, it is the optimal fixation point. High temperature and short time fixation are adopted, and the pan temperature is controlled at 320-350℃ to quickly inactivate enzyme activity, lock in the organic matter accumulated in the early stage, and prevent the aging of plant fibers and the loss of organic matter.

[0032] The tea leaves need to be kneaded several times to adjust the overall material balance of the tea leaves, so that the squeezed water can be reintegrated and absorbed, making the tea soup taste uniform. Then, they are dried at 65℃ until the ratio of free water to bound water approaches 0, and the tea leaves enter a "dormant" state.

[0033] After the above-mentioned initially dried tea leaves are stored for six months to one year, they are roasted according to the desired aroma. If only the tea aroma needs to be restored: roast at 65℃ for 6 hours.

[0034] For a richer aroma and smokiness, roast the tea at 80℃ for 6 hours, then at 120℃ for 2-3 hours. (During roasting: avoid high heat to prevent the sugars from burning.)

[0035] Products produced using eco-friendly processes are rich in nutrients. No high-heat roasting is needed to remove odors; the roasting process is merely for enhancing aroma, reflecting the mature quality of human craftsmanship. The tea liquor is golden and clear, with a rich and lasting floral and fruity aroma. It is smooth on the palate, with a harmonious balance of sweet, salty, and bitter flavors, a strong aftertaste, and thick, soft, and glossy tea leaves. It is slightly alkaline (pH 7.3).

[0036] This invention rationally utilizes the principle of biological oxidation to precisely regulate the ecological indicators of tea leaves, restart the life activities of tea leaves, promote metabolism, and achieve the "rebirth" of tea leaves.

[0037] The repeated shaking action of this invention can restore the balance between transpiration pull and root pressure, rebuild the water cycle, promote the accumulation of carbohydrates, lipids and proteins, and enhance heat resistance.

[0038] The macroscopic effects of sun-drying and shaking the tea leaves are to restore the tea leaf ecosystem and restart aerobic respiration. Microscopically, sun-drying involves the tea leaves obtaining heat through pigments, part of which is used to maintain their body temperature, and the remaining 40% is converted into ATP (a chemical energy source). Maintaining a normal body temperature (the body temperature of all living organisms is 37 degrees Celsius) requires shaking to dissipate heat. While turning the leaves has a similar effect, the motion is smaller and serves as a warming action to prepare the tea for shaking.

[0039] During the greening stage: increase the proportion of bound water in the ratio, improve heat resistance, and increase the amount of sugar reduction.

[0040] The tricarboxylic acid (TCA) cycle proceeds aerobically. Sugars undergo glycolysis to produce pyruvate, which enters the cycle to form citric acid. After four dehydrogenations and one phosphorylation, CO2 is produced, and oxaloacetate is regenerated. This oxaloacetate then condenses with newly generated acetyl-CoA, entering the next cycle. One cycle of the TCA cycle takes 2 hours, during which a second shaking (or "making the tea leaves green") is performed. The degree of shaking depends on the degree of heat dissipation, i.e., the amount of moisture replenished. Normally, morning and afternoon shaking lasts 7-9 minutes, and evening shaking lasts 9-11 minutes. If the tea leaves turn white and weak, the shaking intensity needs to be reduced to 5-6 minutes to nourish the leaves.

[0041] This invention, for the first time based on biological principles, systematically integrates chloroplasts (reducing sugars) and vacuoles (sites for transferring and storing organic matter), while the transferred sugars undergo glycolysis and enter the tricarboxylic acid cycle under aerobic conditions. The NADH+H+ produced in the vacuoles must pass through the 3-glycerophosphate shuttle system and the malate-aspartate shuttle system to enter the inner mitochondrial membrane, enter the respiratory chain, generate ATP through phosphorylation, and release oxygen and hydrogen to combine into water.

[0042] The first shaking initiates sugar reduction and awakens the tea leaves. The second shaking (processing) nourishes the tea leaves, and the third shaking enhances cell vitality, promotes the accumulation of organic matter, and strengthens the tea.

[0043] During the processing of the tea leaves before drying, the aroma changes from grassy to fresh, and finally to fruity. If the leaves are tasteless or have an unpleasant odor, it indicates over-sun-drying or excessive shaking. For example, over-sun-drying causes the tea leaves to suffer from heatstroke, reducing cell vitality; excessive shaking prevents moisture replenishment, resulting in white edges followed by red edges on the leaves. Normally, after the third shaking and withering, the tea leaves have high water saturation and a glossy dark green color.

[0044] The tea liquor prepared by this invention exhibits distinct characteristics of "fragrant, clear, sweet, and lively," with a harmonious and full-bodied balance of sweet, salty, and bitter flavors, and is neutral to slightly alkaline. This is achieved through a combination of room-temperature and high-temperature metabolism in the aforementioned processing. During room-temperature metabolism, minerals such as potassium and sodium are oxidized in the tricarboxylic acid cycle to form alkaline oxides. During high-temperature metabolism, alkaloid metabolism is primarily alkaloid metabolism, producing a large class of nitrogenous compounds that can combine with acids to form salts, reducing the content of theophylline and free acids. The formed salts, in turn, increase the alkalinity of the tea. The water-soluble ash and salts generated in this process are key components constituting the flavor of tea polysaccharides (composed of sugars, pectin, proteins, etc.). They effectively reduce the content of theophylline and free acidic substances, increasing the alkalinity of the tea liquor and making the finished tea an alkaline food. Therefore, the finished tea prepared by this invention through an ecological oxidation process is neutral to slightly alkaline, rather than neutral to slightly acidic.

[0045] Furthermore, the tea prepared by this invention exhibits high quality stability, is minimally affected by climate and temperature changes, and demonstrates good batch-to-batch consistency. The flavor formation mechanism of the tea soup shares the same metabolic pathway as that of ripe fruits, resulting in identical material conditions. The tea soup possesses a strong sense of layering, integrating the advantages of lemon, apple, and amber aromas, which are carried into the water and blended into the three flavors of the tea soup, forming a unique flavor. The invention and its embodiments have been described above. This description is not restrictive, and the embodiments shown are merely one implementation method of the invention; the actual structure is not limited to this. In conclusion, if those skilled in the art are inspired by this invention and design similar structures and embodiments without departing from the spirit of the invention, all such designs should fall within the protection scope of this invention.

Claims

1. A method for ecological oxidation processing of oolong tea, characterized in that, It includes the following steps: a) Picking tea leaves; b) Sun-drying and opening: Sun-dry the tea leaves in the sun, turning and spreading them out continuously during the process, and then move them to the shaking room for opening for 3-6 minutes; c) Withering: After step b) opening the green tea leaves, place the green tea leaves in an artificial climate withering room for the first shaking, let them stand for a period of time, then shake them a second time. After the second shaking is completed, shake them a third time, and let them stand and wither during the shaking intervals. d) Fixation: When the free water / bound water ratio of the tea leaves from step c) is close to or tends to 1, fixation is carried out at 320-350℃. e) Rolling and drying: Roll the blanched leaves and then dry them; f) Roasting: After storing the dried tea leaves for six months to a year, roast them at 65℃ to 120℃ according to the target aroma.

2. The method for ecological oxidation processing of oolong tea according to claim 1, characterized in that, The tea leaves picked in step a) are tea leaves with stems, consisting of one bud and two to three leaves, and with small to medium opening.

3. The method for ecological oxidation processing of oolong tea according to claim 1, characterized in that, The ambient temperature of the artificial climate withering room described in step c) is controlled at 20-22℃, with the airflow moving clockwise to maintain the internal temperature of the tea leaves at 35-37℃.

4. The method for ecological oxidation processing of oolong tea according to claim 1, characterized in that, The specific operation of roasting described in step e) is as follows; If only the aroma of the tea needs to be restored, it only needs to be roasted at 65℃ for 4-6 hours; To achieve a rich, caramelized aroma, roast the tea at 80℃ for 4-6 hours, and then at 120℃ for 2-3 hours, after restoring the tea's fragrance.

5. Oolong tea or Tieguanyin prepared by the ecological oxidation processing method for oolong tea according to any one of claims 1 to 4, characterized in that, The oolong tea or Tieguanyin has a pH of 7-7.5 and has floral and fruity aromas and a sweet, salty, and bitter taste.