CN110604186A

CN110604186A - Preparation method of black tea

Info

Publication number: CN110604186A
Application number: CN201910910290.6A
Authority: CN
Inventors: 洪治
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2019-12-24

Abstract

The invention discloses a preparation method of black tea, which comprises the following steps: picking fresh leaves, wherein the time from picking the fresh leaves to spreading and drying the fresh leaves is not more than 8 hours; secondly, spreading and drying fresh leaves: spreading and drying fresh leaves at a thickness of 2-3 cm, and blowing natural wind of 4 m/s for 4-6 hours; thirdly, withering: blowing hot air of more than 8 m/s for 4-6 hours; turning over the green tea leaves in the withering trough once every one hour; fourthly, rolling: regulating the pressure of the barrel cover according to the light, heavy, light, heavy and light principles, completing the deblocking within 2 hours by using a deblocking machine; fifthly, fermentation: putting the deblocked tea leaves into a high-temperature and high-humidity fermentation chamber for fermentation for less than 2 hours, wherein the accumulated fermentation degree reaches 80-85%; sixthly, drying, wherein the drying comprises three steps of primary drying, foot drying and secondary drying; the process is finished within 24-30 hours from the picking of fresh leaves to the completion of the primary drying and full drying, and finally the black tea with good color, fragrance, taste, shape and charm is prepared.

Description

Preparation method of black tea

Technical Field

The invention relates to the technical field of tea processing, in particular to a method for making black tea.

Background

The black tea is the tea with the largest world yield, accounts for about 70% of the total global yield, belongs to the whole fermentation tea, and is prepared by the processes of picking fresh leaves, spreading and drying in the air, withering, rolling, fermenting and drying. However, the processing of the black tea is an international problem which is not solved so far, and the taste of the traditional black tea is expressed by nine acids in ten, nine impurities in ten and nine dry mouths in ten, because the scientific research workers and the production enterprises lack systematic understanding and profound understanding of the fermentation rule of the black tea, the deterioration of the tea in different degrees occurs in the processing process. Tea research units and production enterprises consider that: the fermentation of black tea is completed in the fermentation step, so that the traditional process is difficult to produce the black tea with good quality. The traditional black tea has miscellaneous and unclear fragrance, is not fresh and cool, has no saliva or body fluid, is heavy in bitter taste, generally has sour taste and water taste, and has rancid taste and stink taste in some cases, the finished tea is not glossy, the liquor color is turbid, the leaf bottom is dark, and the total quality is not good.

Disclosure of Invention

The invention aims to provide a method for making black tea aiming at the defects and shortcomings of the prior art, which refines the fermentation activities of each step of the black tea, accurately controls the accumulative fermentation degree of each step, finally enables the accumulative fermentation degree to reach 95-100%, and produces rancid taste without excessive fermentation, thereby obtaining the black tea with good color, fragrance, taste, shape and charm.

In order to achieve the purpose, the invention adopts the technical scheme that: it comprises the following steps:

picking fresh leaves, wherein the time from picking the fresh leaves to spreading and drying the fresh leaves is not more than 8 hours;

secondly, spreading and drying fresh leaves: spreading and drying fresh leaves at a thickness of 2-3 cm, and blowing natural wind at a speed of 3-5 m/s for 4-6 hours;

thirdly, withering: blowing hot air of more than 7-9 m/s for 4-6 hours; turning over the green tea leaves in the withering trough once every one hour;

fourthly, rolling: regulating the pressure of the barrel cover according to the light, heavy, light, heavy and light principles, completing the deblocking within 2 hours by using a deblocking machine;

fifthly, fermentation: putting the deblocked tea leaves into a high-temperature and high-humidity fermentation chamber for fermentation for less than 2 hours, wherein the accumulated fermentation degree reaches 80-85%;

sixthly, drying: the drying comprises three steps of primary drying, foot drying and secondary drying; the process is completed within 24-30 hours from the picking of fresh leaves to the completion of the primary drying.

Further, the specific steps of picking fresh leaves in the step one are as follows:

a. picking fresh leaves in the continuous sunny day, wherein the fresh leaves cannot be exposed to the sun after being picked into a breathable bamboo basket, a bamboo basket or a bamboo basket;

b. when the fresh leaves are contained, the volume of the fresh leaves can not exceed two thirds of the volume of the bamboo basket, the bamboo basket or the bamboo basket;

c. if the ambient temperature is higher than 25 ℃, heat dissipation is performed once every two hours, so that the fresh leaves in the container are prevented from being damaged by high temperature;

d. when transporting fresh leaves, the fresh leaves are gently taken and put; spreading and airing immediately after transportation is finished, wherein the time from picking of fresh leaves to spreading and airing of the fresh leaves is not more than 8 hours;

further, the specific method for spreading and airing the fresh leaves in the second step is as follows: spreading and drying fresh leaves on a bamboo sieve, keeping the thickness of tea leaves at 2-3 cm, keeping the air speed at 4 m/s and the ambient temperature at 15-25 ℃ for 4-6 hours without stopping blowing by a hanging fan;

further, the specific steps of withering in the third step are as follows:

a. transferring the fresh leaves into a withering trough, keeping the thickness of the fresh leaves at 5-10 cm, and blowing cold air by using an air blower at the air speed of more than 8 m/s and the temperature of 15-25 ℃ for 2 hours;

b. then blowing hot air with the wind speed of more than 8 m/s, the temperature of the hot air of 28-30 ℃ and the time of 2 hours;

c. then blowing hot air with the air speed of more than 8 m/s at the temperature of 30-35 ℃ for 2-4 hours;

d. turning green tea leaves in the withering trough once every hour in the withering process so as to facilitate uniform water flowing; until the color of the tea leaves becomes dark and loses luster, the texture becomes particularly soft, the tea leaves are grabbed into a mass by hands, the cumulative fermentation degree reaches 5 percent, and the next step is immediately carried out;

further, the specific method for rolling in the fourth step is as follows: transferring the withered tea leaves into a rolling machine, adjusting the pressure of a barrel cover according to the light, heavy, light, heavy and light principles, wherein the rolled tea leaves are required to be tight and thin and uniform, the whole rolling step is completed within 2 hours, the accumulated fermentation degree reaches 10-15%, and the next step is immediately carried out after deblocking by a deblocking machine;

further, the concrete method of fermentation in the fifth step is as follows: and (3) fermenting the deblocked tea leaves in a high-temperature and high-humidity fermentation chamber, wherein the temperature in the fermentation chamber is 35-40 ℃, the relative humidity of air is above 90, the whole fermentation time is within 2 hours, the accumulated fermentation degree reaches 80-85%, and the next step is immediately carried out.

Further, the drying in the sixth step comprises the following specific steps:

a. the initial drying temperature is 100-;

b. the enough drying temperature is 80-100 ℃, the enough drying is finished to reach nine-percent dryness, the enough drying is finished, the accumulated fermentation degree reaches 90-95 percent, the initial drying and the enough drying are finished within 2 hours, the raw tea is prepared, and the tea quality is basically shaped;

c. after the processes of stacking, winnowing, picking out tea stalks, fish leaves and refining old yellow slices, re-drying is carried out, the re-drying temperature is 60-80 ℃, the re-drying time is 1-2 hours, and the accumulated fermentation degree after the re-drying is finished reaches 95-100%.

After the scheme is adopted, the invention has the beneficial effects that: in the processing process of the black tea, spreading and drying are slow fermentation processes, withering is a quick fermentation process, rolling is a quick fermentation process, entering a high-temperature and high-humidity fermentation chamber is a violent fermentation process, and drying is quick fermentation of residual active enzymes; the enzymatic oxidation reaction of the tea leaves starts from the moment when the tea leaves leave the tea trees, and the fermentation activity basically stops until the water content of the primary tea leaves is lower than 8 percent throughout the processing process; the method refines and accurately controls the fermentation activity and the fermentation degree of each step, finally enables the accumulated fermentation degree to reach 95-100%, and avoids sour and rancid generated by excessive fermentation; the black tea prepared by the preparation method disclosed by the invention is dark brown and oily in color, has curled and compact strips, red and bright soup color, clear and bright fragrance, pure and pure fragrance, contains various flowery smells and delicate fragrance of the valleys, is delicate, soft, lasting, smooth and sweet in taste, generates body fluid, is fresh and alive, has long aftertaste, and is red, bright and alive in leaf bottom and rich in elasticity.

Drawings

FIG. 1 is a comparison of the color of the dry tea of the black tea of the present invention and that of the normal black tea;

FIG. 2 is a comparison of tea soup of black tea of the present invention and ordinary black tea;

figure 3 is a comparison of the leaf base of black tea of the invention with that of normal black tea.

Detailed Description

The present invention is further described below.

The technical scheme adopted by the specific implementation mode is as follows: firstly, picking fresh leaves:

d. when transporting fresh leaves, the fresh leaves are gently taken and put; and (4) spreading and airing immediately after transportation is finished, wherein the time from the picking of the fresh leaves to the spreading and airing of the fresh leaves is not more than 8 hours.

Secondly, spreading and drying fresh leaves: spreading and drying fresh leaves on a bamboo sieve, keeping the thickness of tea leaves at 2-3 cm, keeping the air speed at 4 m/s and the ambient temperature at 15-25 ℃ for 4-6 hours without stopping blowing by a hanging fan;

the spreading and drying of the fresh leaves is a slow fermentation process, the fresh leaves are thinly spread by 2-3 cm, and a ceiling fan is used for blowing natural wind continuously to cool the fresh leaves, so that the heat generated in the picking and transporting processes of the fresh leaves is reduced; the natural wind is also used for evaporating the water on the surface of the fresh leaves to drive the water of the tea leaves to flow away, promote enzymatic oxidation reaction, facilitate the generation, accumulation and conversion of inclusion, remove green fishy smell and increase flower fragrance.

Thirdly, withering:

the withering is a rapid fermentation process, and the method of increasing wind power and conveying hot air increases the pressure difference of water molecules inside and outside the tea leaves, accelerates the water loss of the tea leaves, accelerates enzymatic oxidation reaction, further removes the fishy smell and increases the flower fragrance.

Fourthly, rolling:

transferring the withered tea leaves into a rolling machine, adjusting the pressure of a barrel cover according to the light, heavy, light, heavy and light principles, wherein the rolled tea leaves are required to be tight and thin and uniform, the whole rolling step is completed within 2 hours, the accumulated fermentation degree reaches 10-15%, and the next step is immediately carried out after deblocking by a deblocking machine;

the rolling is a rapid fermentation process, the withered leaves are placed into a tea rolling machine for rolling continuously, so that not only are tea strips tightly tied and curled, but also the cell tissues of the tea are damaged, the temperature of a semi-finished product can be increased by frictional heat generation, the oxidation of overflowing tea juice is accelerated, and the chlorophyll is promoted to be converted into lutein and phyllanthin.

Fifthly, fermentation: placing the deblocked tea leaves into a high-temperature and high-humidity fermentation chamber for fermentation, wherein the temperature in the fermentation chamber is 35-40 ℃, the relative humidity of air is above 90, the whole fermentation time is within 2 hours, the accumulated fermentation degree reaches 80-85%, and immediately entering the next step;

the fermentation process is violent in the high temperature and high humidity fermentation chamber, the temperature in the fermentation chamber is 35-40 ℃, the relative air humidity is over 90, the enzyme activity is highest, the enzymatic reaction of various proteases is violent, and the components are converted and superposed.

Sixthly, drying, wherein the drying comprises three steps of primary drying, foot drying and secondary drying:

a. the initial drying temperature is 100-;

c. after the processes of stacking, winnowing, picking out tea stalks, fish leaves and refining old yellow slices, re-drying at the temperature of 60-80 ℃ for 1-2 hours, wherein the accumulated fermentation degree reaches 95-100 percent after re-drying;

the drying process of primary drying and sufficient drying is a rapid fermentation process of residual active enzyme. The drying aims at: inactivating the activity of protease, and stopping fermentation; the water content of the semi-finished tea is reduced, so that the tea can be preserved easily; emits green grass gas with low boiling point and activates aromatic substances with high boiling point. The activity of most of protease is passivated after the temperature is higher than 80 ℃ and is irreversible, but a few of high-temperature resistant residual active enzymes continue to perform enzymatic oxidation reaction, the accumulated fermentation degree reaches 85-90% after the initial drying is finished, and the accumulated fermentation degree reaches 90-95% after the full drying is finished; until the water content is less than 8%, the fermentation activity is basically finished, the charcoal baking and re-firing are finished, and the accumulated fermentation degree reaches 95-100%.

The process is completed within 24-30 hours from the picking of fresh leaves to the completion of the primary drying (namely the preparation of the raw tea), thereby improving the freshness and the purity of the tea.

In the processing process of the black tea in the specific embodiment, the spreading and drying is a slow fermentation process, the withering is a rapid fermentation process, the rolling is a rapid fermentation process, the fermentation chamber entering high temperature and high humidity is a violent fermentation process, and the drying is rapid fermentation of residual active enzymes; the enzymatic oxidation of tea begins at the moment the tea leaves the tea plant and continues throughout the process until the water content of the raw tea is less than 8% and the fermentation activity is essentially stopped. The method refines and accurately controls the fermentation activity and the fermentation degree of each step, finally enables the accumulated fermentation degree to reach 95-100%, and avoids sour and rancid generated by excessive fermentation; the black tea prepared by the specific embodiment has black brown and oily color, curled and compact strips, red and bright soup color, clear and bright color, pure fragrance, various flowery smells and delicate fragrance of the valley, delicate, soft, lasting, smooth and sweet taste, body fluid generation, freshness, long aftertaste, red, bright and fresh leaf bottom and high elasticity.

Compared with the common tea, the black tea prepared by the preparation method of the black tea of the invention has the advantages that: as shown in the comparative figure 1, the left side is the black tea of the invention, and the color of the dry tea is more oily than that of the common tea; as shown in the comparative figure 2, the left side is the black tea of the invention, and the tea soup is clearer and brighter than the common tea; as shown in the comparison of FIG. 3, the left side is the black tea of the present invention, and the bottom is more brilliant than the common tea. The flavor of the tea is also distinctive, and the specific expression is as follows: 1. the cleanliness is good, and the foreign flavor and the fire flavor are not generated; 2. pure fragrance, sweet taste, good activity, stereoscopic impression, layering sense and lasting aftertaste.

The above description is only for the purpose of illustrating the technical solutions of the present invention and not for the purpose of limiting the same, and other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention should be covered within the scope of the claims of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A preparation method of black tea is characterized by comprising the following steps: it comprises the following steps:

2. A process of making black tea according to claim 1, wherein: the specific steps of picking fresh leaves are as follows:

3. A process of making black tea according to claim 1, wherein: the specific method for spreading and airing the fresh leaves comprises the following steps: spreading and drying fresh leaves on a bamboo sieve with the tea leaf thickness of 2-3 cm, keeping the air speed of 4 m/s and the ambient temperature of 15-25 ℃ with a hanging fan, and spreading and drying for 4-6 hours.

4. A process of making black tea according to claim 1, wherein: the specific steps of withering are as follows:

d. turning green tea leaves in the withering trough once every hour in the withering process so as to facilitate uniform water flowing; until the tea leaves become dark and lose luster, the texture becomes particularly soft, the tea leaves are grabbed by hands to form a ball, the cumulative fermentation degree reaches 5 percent, and the next step is immediately carried out.

5. A process of making black tea according to claim 1, wherein: the specific method for rolling comprises the following steps: transferring the withered tea leaves into a rolling machine, adjusting the pressure of a barrel cover according to the light, heavy, light, heavy and light principles, wherein the rolled tea leaves are required to be tight and uniform, the whole rolling step is completed within 2 hours, the accumulated fermentation degree reaches 10-15%, and the next step is immediately carried out after deblocking by a deblocking machine.

6. A process of making black tea according to claim 1, wherein: the specific method of fermentation is as follows: and (3) fermenting the deblocked tea leaves in a high-temperature and high-humidity fermentation chamber, wherein the temperature in the fermentation chamber is 35-40 ℃, the relative humidity of air is above 90, the whole fermentation time is within 2 hours, the accumulated fermentation degree reaches 80-85%, and the next step is immediately carried out.

7. A process of making black tea according to claim 1, wherein: the drying method comprises the following specific steps:

a. the initial drying temperature is 100-;