Green tea manufacturing process China's green tea production is diverse and wide-ranging. Green tea is produced in almost all of the country's 18 tea-producing provinces and regions, but it is mainly produced in Zhejiang, Anhui and Jiangxi provinces, followed by Hunan and Sichuan. , Taiwan and other provinces.

Green tea can be divided into four categories according to the production method, namely fried green tea, baked green tea, steamed green tea and sun-dried green tea. All four categories of green tea are produced in China, especially fried green tea.

Chinese fried green tea can be divided into long fried green (such as eyebrow tea), round fried green (such as pearl tea), flat fried green (such as Longjing, Qiqiang), etc. according to the product form. The quantity is mostly long-fried green, which is called eyebrow tea after refining and shaping. It is China's important export green tea variety and enjoys a high reputation in the international market.

In addition to eyebrow tea, China's exported green tea also includes pearl tea, scented tea and various famous green teas. The total annual export volume of green tea is nearly 70,000 tons.

Nearly all famous and high-quality green teas produced in various places are handicrafts. They are characterized by beautiful shapes, green colors, fresh and mellow aromas, and are the best among green teas.

1. Initial production of long strips of green tea

Some people think that "black tea grows on black tea trees, and green tea grows on green tea trees." This is a big misunderstanding. The distinction between black tea and green tea depends entirely on different tea-making processes. Green tea production is different from black tea and other teas. The key lies in the first process in the initial production, that is, finishing. After the fresh leaves are cured and the enzyme activity is inactivated, the various chemical components contained in them basically undergo thermophysical and chemical changes due to the action of heat without the influence of enzymes, thus forming the quality characteristics of green tea.

(1) Greening

Wrapping plays a decisive role in the quality of green tea. Therefore, it must be taken seriously and the operation should be strictly required.

The factors that affect the quality of curing include pot temperature, amount of leaves, machine type, time, curing method, etc. They are a whole, interrelated and restricting each other, and cannot be divided mechanically.

Pot temperature: In order to achieve the purpose of destroying enzyme activity, evaporating water, and producing aroma, a certain pot temperature must be achieved. Production practice has proved that if the temperature of the greening pot is too low, the bursting sound of tea leaves in the pot will not be heard when the fresh leaves are put into the pot, and red stems and red leaves will inevitably appear, resulting in a decline in tea quality.

The reason for the redness of the green leaves is that the leaves are not heated enough during the greening process, and the leaf temperature rises slowly, which cannot denature and coagulate the enzyme protein in a short time. On the contrary, it also intensifies the activity of the enzyme, resulting in colorless Tea polyphenols undergo enzymatic oxidation and quickly turn into red oxides. This is the basic reason why cured leaves produce red stems and red leaves.

The activity of enzymes in tea begins to increase as the temperature increases. When the temperature reaches 40-45°C, the enzyme activity is the most intense. If the temperature continues to increase, the enzyme activity begins to inactivate. When the leaf temperature rises to 70°C, the activity of the enzyme is destroyed. Therefore, if the leaf temperature can be quickly raised to above 70°C in the early stage of greening, it can effectively prevent the production of red stems and red leaves.

High curing temperature can quickly inactivate the activity of enzymes, but too high a temperature is also detrimental to the quality of tea. It will cause scorch spots and bursting spots in the tea, especially the tips of the buds and the edges of the leaves. Burning is one of the main causes of smoky tea.

Using an ordinary thermometer to measure the temperature of the tea pot, the current method is very inconsistent and has a large error. It is also difficult to accurately express the actual temperature of the tea pot. For example, when measuring the pot temperature with a mercury thermometer, due to the small contact area between the thermometer and the pot wall, when the bottom of the pot turns dark red, it is only about 300°C

, but when the pig iron reaches dark red, its actual temperature It is 500-700℃. When it is orange-yellow, it is about 1000℃. Therefore, the pot temperature measured by the thermometer is far lower than the actual temperature of the pot wall.

According to tests, when using a thermoelectric corner measuring machine for pot-type greening, if red stems and red leaves are not to be produced, the pot temperature should not be lower than 400°C; otherwise smoke and burnt gas will not be produced, the pot temperature should not be higher than 470°C. ℃. In order to obtain killed green leaves without red stems, red leaves, or smoke scorch, you should first cover and kill for 2 minutes, so that the leaf temperature quickly rises to 65-70°C, then uncover the cover and stir-fry until the kill is complete. This is the best pot. The temperature should be 430-460℃. Within this range, the redness of the pot cannot be seen even in dark conditions, and only the slight emblem on the surface of the pot is a bit "grey" under natural light. However, in production, the pot is often burned red when finishing, and its actual temperature far exceeds 500°C. This is the main cause of smoked tea.

Tender killing and old killing: The so-called tender killing means that the time should be shorter and the water should evaporate less. On the contrary, it is Lao Sha. Generally speaking, young leaves should be killed early, and old leaves should be killed young. Because the young leaves contain a lot of water and have strong enzyme activity, the leaves are tough and sticky, so appropriate old killing will help improve the quality. Old leaves contain less water and have lower enzyme activity. Appropriate tender killing is beneficial to the formation of cords and reduces the amount of broken tea. The degree of curing is generally determined by sensory evaluation. When the cured leaves reach the point where they can be kneaded into a ball, are slightly elastic, and the young stems are not easy to break; the color is dark green, the leaf surface has lost its luster, and the leaf weight loss rate is about 40%, it is moderately cured.

The green tea is too tender, and there are many broken tea pieces after rolling, and the appearance is poor, the aroma is green, and the taste is astringent. The green tea is too old, and there are too many broken tea pieces after rolling, and it is difficult to form into strips, and it is easy to Produces smoke. The weight of 100 kilograms of fresh leaves after curing is about 63 kilograms, which is moderate. The moisture content of cured leaves is approximately 60%. For fresh leaves with different degrees of tenderness and tenderness, the more suitable moisture contents for green leaves are as listed in the table below.

Recommended moisture content of dried green leaves

Fresh leaf tenderness? Moisture content index of dried green leaves (%)

Tender? 58-60

Medium?61-62

Old?63-64

The moisture content of dried green leaves can be calculated by the following formula:

Moisture content of dried green leaves (%) = 1 —Fresh leaf weight/killed leaf weight·(1-moisture content of fresh leaves)

Example: The moisture content of fresh leaves is assumed to be 75%, and 10 kg of fresh leaves are added to each pot. After finishing, the moisture content is 6.25 Kilogram, what is the moisture content of green leaves?

Suppose the moisture content of the dried green leaves is

That is, the moisture content of the dried leaves is 60%.

Both killing and killing: The so-called killing is to put a lid on the tea pot. The so-called thorough killing means to uncover the cover and shake things up. The correct way to kill the greens is to suffocate them for about 2 minutes. When the water vapor overflows to the mouth of the pot, immediately remove the lid and kill them until the greens are completed. Stifling first and then shaking can increase the temperature of the leaves, which is conducive to even and thorough killing and avoids the production of red stems and red leaves. However, if the leaves are stuffed for too long, the leaves will become yellow and ripe. If thorough killing is carried out throughout the process, not only will the killing be uneven, but red stems and red leaves will often occur. In short, if you use simmering first and then shaking when curing, the quality of the cured leaves will be better, the work efficiency will be high, and the fuel will be saved. If it shakes first and then becomes dull, the greening will be uneven and red stems and red leaves will easily occur. The whole process of killing is thorough, the killing is uneven, and the number of red stems and red leaves increases. If it is completely stuffed, it is easy to produce yellowing and ripeness, and the quality is not good. When killing with suffocation, the young leaves should be suffocated for a shorter time and the old leaves should be suffocated for a longer time.

Finishing of rainwater leaves:

Generally, the surface moisture content of fresh leaves exposed to dew is about 20%, and the surface moisture content of rainwater leaves is about 30%. With so much water attached to the leaf surface, it takes a lot of heat to evaporate the water during curing. Therefore, when the rainwater leaves are cured, the amount of leaves must be reduced and the pot temperature must be appropriately increased to ensure the quality of the cured leaves.

The type of tea fixing machine also has a great impact on the quality of tea making. There are many types of green fixing machines currently used in our country, which can be roughly divided into six categories and nearly 20 types. Because different types of green tea fixing machines have different effects, the quality of the tea produced will also be different. Below is a brief introduction to various representative models and their tea-making quality characteristics.

Pot type finishing machine:

This type of finishing machine mainly has three forms, namely one stove and one pot (such as 6CS-84 single pot finishing machine), one stove and two pots (such as the 6CS-84 double-pot continuous greening machine) and one stove and three pots (such as the Zhejiang Lin'an three-pot continuous greening machine). There are also models of one stove and multiple pots. In terms of use, one stove with multiple pots can save fuel, but as the number of pots increases, if the leaf frying hand is not flexible enough, it is easy to cause the leaves to be unclear from pot to pot, increasing the chance of smoked tea. In terms of tea craftsmanship and fuel saving, it is more reasonable to use one stove and two pots, and it is easier to control

the setting temperature, making it high first and then low.

The main advantages of pot-type greening are: first, the stir-fry hands can stir-fry the greening leaves during the greening process, which exerts a certain pressure on the greening leaves and can have a slight rolling effect, which is conducive to the formation of better texture. Secondly, due to the slight rolling effect, part of the leaf tissue is initially broken during the curing process, which allows oxygen to directly penetrate into the broken cells, prompting some tea polyphenols to produce light The high degree of oxidation reduces the green and astringent taste of the tea soup, which is conducive to obtaining a rich and mellow taste and a bright yellow-green soup color.

Due to the above two points, the pot-type greening machine has better quality than other greening machines without speculators. my country's Zhejiang, Anhui, and Jiangxi regions mainly produce fried green tea. The top-grade green tea has a strong chestnut aroma, a rich and refreshing taste, and a bright yellow-green soup color, forming a Chinese-style green tea

style. It is inseparable from the widespread and correct use of pot finishing.

According to production practice, there are three basic experiences in making good use of the pot-type greening machine.

First of all, after the fresh leaves are poured into the blanching pot, they should be immediately covered and simmered for about 2 minutes. When a large amount of water vapor overflows to the mouth of the pot, the lid should be opened and shaken until the blanching is completed. This can increase the leaf temperature and make it less likely to produce red stems and red leaves.

Secondly, speculators must be flexible, and the leaf-out plate must move up and down to avoid unclear leaves and scorched tea. The curing pot needs to be cleaned every day, and 3-5 grams of asphalt is put into the curing pot every hour or so to increase the lubrication of the pot surface and reduce the adhesion of tea glue. After the pot gels, the tea will inevitably become scorched, the tea soup will be turbid, and there will be a lot of sediment. Smoked tea not only destroys the normal color, aroma and taste of tea, but also often contains carcinogenic 3, 4-benzopyrene. Therefore, we should try to overcome it in the tea making process.

Thirdly, according to the requirements of the tea making process, the temperature of the pot must be high first and then low. In this way, red stems and red leaves can be reduced, smoke scorch can be avoided, and it is easy to kill evenly and thoroughly, thereby obtaining the required tea. Kill the green leaves.

Trough-type greening machine: The pot body of the trough-type greening machine is cylindrical and semicircular, with a radius of 300 mm and a length of 4000 mm. It is connected by 8 "tile-shaped" cast iron parts. On a spindle in the middle of the trough pot, 15 pairs of frying hands with a certain inclination angle are installed, so that the cooked leaves are gradually stir-fried from the entrance of the trough pot

to the exit to achieve continuous cooking. Purpose.

Its fixing principle is basically the same as that of the pot method. It also involves stir-frying with hand stir-frying, which has a certain rubbing effect on the leaves, so the quality of the tea is basically close to that of the traditional pot method.

The trough type has higher efficiency than the pot type, saves about 50% of fuel than the pot type, and operates continuously. But it has a big shortcoming, that is, the first piece of the tank pot is easy to burn due to the concentration of fire points, causing smoke leakage. At the same time, there are seams at the joints of the "tile-shaped" cast iron parts. After stuffing the tea leaves, burnt powder will form, which will stick to the dried leaves and affect the quality.

When the pot slices are burned until they turn red, the green leaves and tea will have a strong smell of smoke. Therefore, do not use too much heat.

Bottle-type fixing machine:

There are many models of bottle-type fixing machines. The main thing they have in common is that they perform intermittent rolling operations. The difference is that the bottle body has Length, short, diameter. This type of greening machine is used for greening fresh leaves below the third level. It is easy to produce more yellow flakes. The strips are worse than the pot type, and the quality of the green leaves is not ideal. It has been eliminated in Zhejiang, Anhui and Jiangxi.

Roller type finishing machine:

There are 5-6 types of roller finishing machines currently used in production. The drum greening machine has the advantages of easy operation, low labor intensity, high work efficiency, fuel saving, and continuous operation. However, it is easy to produce green and astringent tea, and the tea-making performance needs to be improved.

The efficiency of the drum fixing machine is related to the diameter of the cylinder. The larger the diameter of the cylinder, the higher the efficiency. A drum with a diameter of 700-800 mm can kill about 150 kilograms of fresh leaves of grades 1-2 and about 200 kilograms of fresh leaves of grades 3-5 per hour. The length of the drum fixing machine's fixing time (the residence time of the leaves in the drum) varies, ranging from only half a minute to 6 minutes. If the curing time is less than 3 minutes, the finished tea will often have a heavier astringency.

The speed of the cylinder of the drum fixing machine and the size of the helix angle in the cylinder determine the length of the fixing time and are important factors in the fixing quality. Practice has shown that the helix angle within 60 cm of each end of the cylinder should be greater than 45 degrees to ensure smooth leaf entry and exit and reduce leaf sticking at both ends of the cylinder. The helix angle in the middle section of the tube should be no more than 15 degrees, which is beneficial to prolonging the residence time of leaves in the tube to ensure no less than 3 minutes.

According to production experience, the following two points should be paid attention to when using the roller greening machine:

The firepower should not be too strong, and the amount of leaves should not be too much. The judgment method is: during the curing process, when observing the tumbling leaves in the drum, if you can see clearly and there is no water vapor retained in the drum cavity, it indicates that it is suitable; if water vapor comes out from both ends of the drum and you cannot clearly see the leaves turning in the drum, It means that too many leaves are thrown in, which will affect the normal rolling of the leaves and easily produce half-cooked smoky tea.

Because the water loss in different parts of the buds and leaves of the leaves after the roller is very unbalanced, the leaf edges lose more water, and the leaf veins lose less water. The total water content of the leaves is often high, and the leaf quality is not suitable for kneading. Therefore, it is best to place a fan at the exit of the drum or connect it to a vibrating trough to allow it to be ventilated and cooled.

Promote the uniform distribution of water in the leaves and continue to evaporate. In this way, it is conducive to the kneading process. strip.

Roasted silk roller fixing machine:

The roasted silk roller fixing machine was originally a dryer used in cigarette factories to bake tobacco leaves. Its style is similar to the tea drum fixing machine. The machine is connected to the boiler, and the steam generated by the boiler is passed through the pipe to the steam pipe in the drum, and the drum is heated for completion. The steam pressure used is generally 7 kg/cm2, and the tube wall temperature inside the cylinder is about 150°C. The biggest advantage of this green tea fixing machine is that the heating temperature is stable and easy to control, it will not produce smoked tea, and the tea making is also clean and hygienic. The disadvantages are that the heat supply is slow and the temperature is too low. The moisture content of the cured leaves is often high, and the leaves are stuffy and ripe. When kneading, it is easy to peel and break, which affects the tightness and integrity of the ropes. Due to the yellow ripening phenomenon of the cured leaves in the inner substance, the tea produced also has a "ripe rice dumpling leaf flavor" and the fragrance is poor in freshness. This machine is used for tea leaves and needs to be improved.

Steam fixing machine:

Used for fixing steamed green tea. The main body of this kind of greening machine is a mesh roller with a porous steam nozzle in the middle. The steam directly steams the leaves, and the greening time is about half a minute. The leaves of steamed green leaves are green in color and the water content is about 5% higher than that of fresh leaves.

Of the six types of finishing machines discussed above, the drum finishing machine is currently most used in production.

(2) Rolling

Rolling is a process for shaping the strip shape of fried green tea, and it also plays an important role in improving the flavor concentration of the finished tea. At present, the rolling operation of bulk green tea in my country has been mechanized.

There are many types of rolling machines used for making green tea, with different models and different mechanical properties. Production practice experience has proven that large-scale machines are not suitable for rolling green tea. Large-scale machines have large kneading buckets, large amounts of leaves, long kneading times, and high leaf temperatures during rolling, which can easily cause the kneaded leaves to become yellow and ripe. Generally, a barrel diameter of 55 cm is more suitable; for small production volumes, a barrel diameter of 45 cm can be used, and for large production volumes, a barrel diameter of 65 cm can also be used. The rolling machines commonly used for making green tea are listed in the table below.

Green tea kneading machine

Rolling machine model barrel diameter (mm) amount of leaves (kg) hourly output (kg)

Model 40 400? 1020

Type 45? 450? 15? 30

Type 55? 55035 70

Type 60? 65065 100

For making green tea The rolling process can be divided into cold kneading and hot kneading. The so-called cold kneading is the kneading of the green leaves after cooling, while the hot kneading is the kneading of the green leaves while they are hot without cooling. Young leaves should be cold-kneaded, because young leaves have less fiber, greater toughness, thin cuticles, and more water-soluble pectin, which can easily form strips during rolling. Moreover, cold-kneading young leaves can maintain the bright yellow-green color of the soup and the tender green leaves. end. Old leaves should be kneaded with heat. Because old leaves have a lot of fiber and are thick and hard, they are not easy to form into strips when rolled. Hot kneading takes advantage of the characteristics of the leaves that become soft when heated, which is beneficial to kneading the strips, reducing the amount of broken tea, and improving the appearance. quality.

Determination of the amount of leaves thrown: There is a certain suitable range for the amount of leaves thrown into various rolling machines. Too few leaves will reduce the effect of rolling and pressing, making it difficult to knead the rope tightly; too many leaves thrown in , the leaves are blocked from turning in the kneading bucket, resulting in uneven kneading. The bottom tea is often broken into pieces, and the upper tea is often in strips. This is an important reason for the problems of loose, flat, and broken strips of tea.

Twisting and pressing: The degree of pressure and the time of pressure during the rolling process have a great impact on the tightness and crushing of the tea ropes. The degree of twisting has a greater relationship with the damage rate of leaf tissue and the color, aroma and taste of the inner substance. The pressing principle of the entire kneading process should be "light, heavy and light".

No pressure should be applied during the first 5 minutes of rolling. Wait until the leaves are gradually rolled into strips along the main veins before pressing. The degree of pressure should be determined according to the age of the rolled leaves. Young leaves should be Light pressure and medium pressure are mainly used, and the pressure on leaves below level three should be gradually increased. The specific control can be carried out according to the following diagram: Kneading starts? Kneading ends

Air pressure - light pressure - heavy pressure - release pressure

If the pressure is too early or too heavy Or if it is pressed to the bottom, the rope will often become flat and broken, and the color and taste of the soup will not be ideal. The pressing method of kneading for 30 minutes or 45 minutes generally adopts the following procedure:

30′=5′+12′+12′-1′

45′=-5′+18′ +20′—2′

Note: “One” means air pressure or decompression; “Ten” means pressurization.

Twisting time: Determining the length of the rolling time should be based on the following three principles: first, look at the tenderness of the rolling leaves; second, look at the diameter of the kneading barrel; third, look at the tightness of the ropes of the rolling leaves. Taking the 55 type with a kneading barrel diameter of 55 cm as an example, determine the kneading time, and knead the first and second grade fresh leaves for 20-25 minutes.

If the diameter of the kneading barrel is larger than that of model 55, the kneading time should be increased by about 5 minutes; if it is smaller than that of model 55, the kneading time should be reduced by about 5 minutes.

Be careful with re-kneading: the sifted tea is broken into pieces and sifted, or the green tea is stir-fried and then kneaded, which is called "re-kneading". After the tea leaves are re-kneaded, the appearance is more broken, with more bald tea, low refining extraction rate, and more side teas. Especially when the tea leaves are re-kneaded after the second greening process, the degree of breakage is more serious. When the fresh leaves are relatively consistent in age and tenderness, it is best not to re-knead them. However, if the shapes vary in tightness and there are many leaves spread out on the floating surface, the pieces should be broken up and sieved on a 2-3 hole sieve bed to remove the loose floating surface. It’s okay to lift out the tea from the head and knead it again appropriately.

(3) De-blocking and screening

After being rolled, the dried green leaves tend to form clumps, as big as fists and as small as walnuts, which need to be de-blocked by a de-blocking machine. The block wheel struck and the clump was disbanded. The deblocking machine can be equipped with a 5-hole screen to sift out the crushed tea leaves and make them separately from the strips of tea on the screen surface, which can improve the quality of the tea.

(4) Drying

The moisture content of the wet tea base after kneading and deblocking is about 60%. If it is fried and dried directly, it will be very dry in the pot of the frying machine. It quickly forms clumps, and the tea juice easily sticks to the wall of the pot to form burnt, which causes the tea leaves to smell smokey, the tea soup to be turbid, and the sediment to increase. Only by removing part of the water

from the kneaded leaves and then putting them in a pot and frying them dry can the above-mentioned disadvantages be avoided.

The best way to remove water is to dry the rolled leaves in a dryer, that is, dry the green leaves. The dried Erqing should not be dried too dry. Once the Erqing leaves are set, it will be difficult to fry the strips tightly. However, it should not be too wet, otherwise the Erqing leaves will not be able to play the role of the Erqing. The Erqing leaves will still stick to the pan when fried. Form a group. Therefore, water should be removed appropriately when working with Erqing. Generally, it is advisable to reduce the moisture content of Erqingye to 35-40%. Use an automatic dryer or a hand-operated louver dryer to dry Erqing. The air temperature should be controlled at 110-115°C and dried for 9-12 minutes. The thickness of the leaves should be about 2 cm. If the dried Erqing leaves are still relatively moist, they should be cooled in time to dissipate heat and evaporate the water; if the dried Erqing leaves are dry, they should be piled thickly to allow them to regain moisture, or mixed with the damp ones. Stack the two green leaves together and wait until the water is evenly distributed before frying. When using a dryer to dry green leaves, it is best to control the degree of drying by adjusting the amount of leaves or the operating speed of the machine. This is more convenient and reliable than adjusting the air temperature.

The roasted Erqing leaves are elastic when pinched by hand, making it difficult to shape into tea balls, but not loose and slightly sticky. The moisture content of such Erqingye is 35-40%, which meets the requirements for pot frying.

At present, tea farms in towns and villages generally use bottle-type tea frying machines instead of dryers to process second green tea, which is commonly known as "rolling instead of drying".

To do a good job of using rollers instead of drying, the following three points must be mastered:

First, the leaves should be thrown in in batches, and the amount of leaves should not be too much to prevent too many leaves from being thrown in at one time, causing the temperature of the cylinder wall to drop suddenly. , water vapor permeates the tube, and the leaves adhere to the tube wall, and the adhered Erqing leaves burn as the water disappears, forming a smokey smell. Generally, the amount of leaves added to each cylinder of the bottle-type frying dryer is 17-20 kilograms, divided into 2-3 times, and it is appropriate to finish adding the leaves within 2-3 minutes.

Second, the temperature of the bottle machine should not be too low. When the rolling leaves are put in, if there is a slight popping sound in the cylinder, it indicates that the temperature is suitable. After rolling for 8-10 minutes, the furnace door should be opened to lower the fire temperature to prevent the tea leaves in the cylinder from producing explosive spots or even scorching.

Third, the rolling time is about 15 minutes. If the time is too long, the tea leaves will easily turn gray, which will damage the green color of the dry tea. It is best to use a small flat round sieve with a mesh size of 7-8 holes or a manual bamboo sieve to cut the tea leaves after secondary greening. If the broken tea and strip tea are mixed together

If stir-fried, the minced tea will be small in size, sink to the bottom of the pot, and lose water quickly. Drying first will not only increase the content of the minced tea, but also easily cause old fire.

At present, the frying and drying process of fried green tea has many types of frying and drying machines, which are miscellaneous and unmatched. Therefore, there are many forms of frying and drying processes. The most common frying and drying methods are as follows:

Rolling - frying method: The so-called "rolling" means rolling and frying in a bottle-type frying dryer, and the so-called "frying" means frying in a pot-type frying dryer (the same below). If it is directly stir-fried after rolling, the strands of the raw tea will become tighter, but the amount of broken tea will increase, which will harm the economic value of the finished tea.

Roll-Roll-Roll method: The tea leaves are not fried in a pot; they are all boiled and fried in a bottle machine until dry, so it is also called a roll to the bottom. In addition to less broken tea, the Maocha produced by this method has many shortcomings. The main disadvantages are that the shape of the tea is loose, the tea body is round and hooked, and the color is gray like old tea. The appearance quality of products that are rolled to the bottom, commonly known as "rolled green tea", is generally about one level lower than that of normal fried products, so it is best not to use it.

Rolling-kneading-rolling method: After rolling two greens, knead again, then roll and fry until dry. The Maocha produced by this method has a short, bald appearance and contains more powder.

Baking (rolling) - frying - rolling method: This frying method is currently more popular in the fried green tea area. The tea produced is tighter and straighter, with less broken tea and better quality. It should be strongly promoted. Its entire tea-making process is shown in the picture above.

There are currently two types of frying and drying machines used for the initial production of green tea: one is the pot type and the other is the bottle type. There are three types of pot-type frying dryers:

Rotary frying dryer: The working shaft is equipped with 4 iron frying hands and 2 brown frying brushes, and the tea is fried as the shaft rotates. This type of frying hand is the most widely used. Its advantages are simple structure and easy operation, but the shape of the wonderfully prepared tea leaves is looser.

Reciprocating frying and drying machine: This machine imitates the gesture of manual tea frying, and the frying hand swings back and forth to fry tea, so it is called a reciprocating frying and drying machine. This machine must be used with a cylindrical roasting machine, and the two machines are paired into one unit. The tea making ropes are tightly knotted, and the tea leaves are less, but the shape is rounder.

Angle iron hand frying machine: It is another form of rotary drying machine. The frying hand is made of 30*30 angle iron. The length is the same as the radius of the pot. The shaft and frying hand are The hands are connected in a "ten" shape. Install the teapot with an inclination of 6 to 8 degrees toward the outlet. This machine must be used in conjunction with a bottle-type tea frying machine.

When frying tea, more leaves are put into the pot, which makes it easier to fry tightly, but the shape is more broken.

There are many factors involved in making good tea. In addition to tea making technology, the correct use of tea machines is also an important part. A certain type of tea-making machine is generally only suitable for a certain process. However, when making fried green tea in many places now, the bottle machine is used both as a fixing machine and a frying and drying machine, turning fried green tea into a " "Rolled green tea" is of poor quality, resulting in a rough and loose appearance, hooked ropes, and a dark color. "Rolling green tea" has a greater impact on the quality of medium and low tea, mainly containing Huang Pu pieces and a loose bubble shape. It is very detrimental to refined eyebrow tea and damages the economic value of eyebrow tea.

The gap between the frying hand of the pot dryer and the pot wall should be wide at the front and tight at the back. If it is tight at the front and wide at the back, when the frying hand is pushed upward to stir-fry, the tea leaves will get stuck between the frying hand and the wall of the pot, causing the tea leaves to be crushed. Therefore, when installing the teapot, the working axis should be slightly offset below the center line, so that the gap between the frying hand and the proximal end of the pot is about 6 mm, and gradually increases to 10 mm when it reaches the top of the pot edge. This can not only reduce the amount of broken tea, but also make the tea machine run smoothly.

The speed of the 84-type dryer is best controlled at 1820 rpm. Beyond this speed, the amount of broken tea will increase significantly, seriously affecting the appearance and economic value of the tea. If the rotation speed is too fast, just reduce the diameter of the driving wheel on the motor.

The appropriate rotation speed of the rolling machine for making green tea is 48-50 rpm. If it is too fast, the rolling quality will be poor and there will be more broken tea. According to the test, the 55 type twisting machine with a speed of 50 rpm has better twisting quality and less broken ends than the 55 rpm twisting machine, but the strip speed is slightly slower and the work efficiency is slightly lower. In order to ensure the quality of kneading, the rotation speed should not be greater than 50 rpm.

The ribs of the kneading machine should not be too small. If the ribs are worn, they should be replaced in time. If the ribs are too small or worn, the resistance to the kneading leaves will be small, and the tea sticks cannot be kneaded tightly. In addition, the height and width of the rib section should be equal, and the height and width of the rib should be adapted to the diameter of the kneading barrel, that is, as the barrel diameter increases.

Enlarge. The side of the rib bone should be perpendicular to the kneading plate, so that the resistance to the kneading leaves is large, which is conducive to kneading the rope tightly. On the contrary, the fusiform bone with a flat or oval cross section is difficult to knead the rope tightly.

2. Eyebrow-shaped green tea refining

Tea refining, as the name suggests, means fine workmanship. Long-fried green tea, after being refined and shaped, is generally called eyebrow tea. Chinese eyebrow teas include Tunlu, Shulu, Zilu, Raolu, Hanglu, etc. Their preparation methods are not exactly the same, but the basic screening process is Similar.

The eyebrow tea in Zhejiang Province is divided into Hanglu, Wenlu and Suilu. Now we will take Hanglu as an example to illustrate. The whole province of Hanglu is unified into 12 sieve number teas: 4, 5, 6, 7, 8, 10, 12, 24, 34, 80 and 100 hole tea.

Exported eyebrow tea color grade grade

Special one 9371

Special two 9370

Zhen Meizhen one 9369

Zhen 2 9368

Zhen 3 9367

Zhen 4 9366

Zhen Bule 3008

Yucha Grade 1 8147

Xiumei Texiu 8117

Xiu Yi Processing

Xiu San 9380

Piece of Tea 34403? Tea Piece? Broken Tea? Rough Wei ? Fine?

Maocha complex fire rolling strips

4? 5? 6? 7? 8? 10? 12? 16? 24? 34? 80? 100

Mao shake

Mao tease

Front tight door

Complex tease

Machine picking

Fan Grading (split fan, double fan)

Clean machine picking

Electric picking

Hand picking

Fire replenishment

Car color

Clean tea sifting

Second door

Clean tea

Fresh breeze

Assembling, packing and bagging

Process flow chart of the process

(Figure omitted) Schematic diagram of the screen configuration of the screening operation and the sieve number of tea that appears in the export of Mei tea Zhen, Zhenmei, Yucha, Xiumei, Piancha, Broken Tea, Coarse Wei and Xinwei. Each product name is divided into several grades. For example, rare eyebrows are divided into first-level, second-level, third-level, fourth-level rare eyebrows and unclassified rare eyebrows. When exporting eyebrow tea for export, the name of the tea is generally not reported, but code names are used. For example, the first grade of special treasure is 9371, and the first grade of rare eyebrow is 9369. These teas are made from long-fried green tea. The colors and grades of exported eyebrow tea are listed in the table above.

The marking for trade samples is different from the marking for processing samples. Trade samples are marked according to the export tea number. The processing sample mark generally consists of one Chinese character and five Arabic numerals (determined by the export company). The Chinese character is the name of the factory, the first number in Arabic is the year, and the second number is the product name (Zhenmei is 1, Gongxi is 2, Yucha is 3, Texiu is 4, Xiuer and Xiusan are 5 , the piece is 6), the third number is the level, the fourth and fifth numbers are the running numbers. For example, "Ming 81201" is the first batch of grade 2 Zhenmei tea samples shipped from the famous tea factory in 1988.

Chinese green tea is one of the gongfu teas. It is refined and screened very finely and is basically divided into three types - itself type, round body type and tendon type type.

(1) The own way

The technological process is: Maocha reheating - rolling bar - screening - hair lifting - front tight door - reshaping - machine Picking - air selection (split fan, double fan) - electric picking - hand picking - fire replenishment - car color - clean tea sieving - tight door - clean and cool breeze - storage To be put together - evenly stacked and packed into boxes (see "Self-Road Process Flow Diagram").

Reheat: Use a dryer to reheat the fried green tea. Bake until the moisture content is 5-6%.

Rolling: After drying, put the tea into the octagonal roller while it is hot to make the tea body tightly knotted and decoupled. Rolling time is generally 60-70 minutes.

Screening: The rolled Maocha is sieved, and the tea leaves at the bottom of the 4 holes are processed according to its own path. The tea leaves on the 4-hole surface are cut once and re-screened, and the 4-hole bottoms are still merged into the original path. . The 4-hole bottom of the sifted tea leaves is still merged into its own path after being cut once. The screen configuration of the sub-sieve is as shown above.

Mao shaking: The 4-7 hole teas sifted are put on the shaking sifting machine respectively, and the thickness of the tea leaves is preliminarily divided, and thick tea sticks, round-headed tea and thinner tendons are produced. . The shake head of the 7-hole screen size tea is merged into the 5 and 6 hole screen size tea complex, and the 4 and 5 hole screen size tea shake head is integrated into the round body path. The shaker screen configuration is as shown in the table.

Mao sieving: The 4-24 hole tea after sieving is sieved (hair sieved) after being shaken, and high-grade tea needs to be sieved three times. The screen configuration is as shown in the table.

Qianjinmen: 4-6 hole tea hairs are lifted and shaken again, also called Qianjinmen. The purpose is to shake off the tendons and stems, grade the blanks, and improve the purity. The screen configuration is shown in Table 6.

Re-tease: The 4, 5, and 6-hole tea behind the front tight door and the 7-hole tea after the fan is cut are re-teased. The method is the same as the hair teaser.

Machine picking: picking out longer tendons. Using a stepper stem picker, the first grid is large and the second, third and fourth grid are small.

The configuration of the shaking sieve, lifting sieve, front tightening door, and back tightening door in the refining of eyebrow tea can be carried out by referring to the following tables.

3? Initial production of pearl tea

1. Definition

Because the shape of pearl tea is round and tight, like pearls, it is also called round tea. Round fried green tea.

2. Place of Origin

Pearl tea is produced in Zhejiang and Taiwan provinces of my country. The pearl tea producing areas in Zhejiang Province include Shengxian, Xinchang, Dongyang, Shangyu, Fenghua, Yinxian, Yuyao and other counties.

Mao tea is concentrated in Shaoxing Tea Factory and Sanjie Tea Factory for refining and processing. Because in the past Maocha was mainly processed in Pingshui, Shaoxing, it was also known as Pingshui green tea internationally.

3. Quality Characteristics

The shape is round and compact, granular, green in color, the tea bones are heavy and solid, like pearls, the aroma is strong and the flavor is strong, durable for soaking, and the bottom of the leaves is yellow. Bright green, with intact buds and leaves.

4. Production process

Bead tea frying is divided into three steps: greening, rolling and drying.

Drying is divided into four steps: Erqing, small pot, double pot and large pot. Erqingye is fried and dried in a drum dryer (bottle-type fryer), and small pots, double pots, and large pots are fried and dried in the same pearl tea dryer. The equipment for curing and rolling is the same as the equipment for frying eyebrow tea.

(1) Greening

The greening technology for the initial production of pearl tea is basically the same as that for the primary production of eyebrow tea. In terms of specific operation, the main difference is that the pearl tea is stuffed first and then thrown out. After the fresh leaves are put into the pot, use the 84-type fixing machine to simmer for about 3-4 minutes, and use the 64-type fixing machine for about 2.5-3 minutes. When a large amount of water vapor rushes out from the seam of the lid, remove the lid and stir-fry until the leaves turn dark green and the stems are broken and not broken. The moisture content of dried leaves is 60-64%, and the weight loss is about 35-40%.

The method of stuffing the pearl tea first and then throwing it has a short curing time, green leaves and refreshing aroma, which is better than stuffing it first and then stuffing it. The frying time of pearl tea is 1-2 minutes longer than that of eyebrow tea. The purpose of boring is to increase leaf temperature. Make the leaves soft and avoid producing red stems and red leaves, which will facilitate future shaping. However, the frying time should not be too long to prevent water suffocation and yellowing of the leaves.

Appropriate amount of stuffiness is good for killing thoroughly and evenly, especially for reducing the symptoms