Black tea withering equipment

Abstract

The utility model discloses black tea withering equipment. The equipment comprises an upper-layer conveying mesh belt and a lower-layer conveying mesh belt which are opposite in conveying direction, a C-shaped elevator, a fan, a vibration conveying groove and a far infrared light source, infrared withering, automatic leaf turning and oscillating fine manipulation are integrated, the oxidase activity of fresh tea leaves is improved by utilizing far infrared radiation, water flowing of the fresh tea leaves is promoted and the content of aroma prerequisite substances and the activity of related enzymes are improved by utilizing an oscillating fine manipulation technology, and mechanical damage caused by a traditional rocking technology is avoided. The black tea processed by the equipment has remarkable debitterizing and aroma enhancing effects, the content of tea polyphenol is effectively reduced, the content of theaflavin and thearubigins is increased, tea soup is mellow, the aroma is improved, the sensory quality of tea leaves is remarkably improved, the equipment is small and easy to use, the cost is low, the labor cost is remarkably reduced, and the production efficiency is improved. And the method has high practicability and wide applicability.

Description

Technical Field

[0001] The invention relates to tea withering equipment, in particular to black tea withering equipment, and belongs to the technical field of tea processing. Background Art

[0002] Withering of fresh leaves is the first step in the processing of Gongfu black tea, and it is also one of the key steps in the formation of black tea quality. A large number of studies have shown that methods such as light compensation and light shaking can improve the withering quality and improve the quality of black tea.

[0003] In actual production, in order to improve production efficiency, most tea-growing areas, especially those producing both red and green tea, wither the leaves at night and start rolling the leaves the next morning. Therefore, the processes of spreading and turning the withered leaves are all carried out at night.

[0004] Most small and medium-sized tea companies and tea farmers still use manual leaf turning, which is labor-intensive. Since the withering process is mostly carried out at night, it is easy to cause worker fatigue, which affects the withering effect and has low production efficiency. In addition, the leaf turning, shaking and transferring operations will inevitably cause mechanical damage to the fresh leaves, forming dead green leaves, which affects the quality of the withered leaves. In particular, the withering process of making green leaves is more labor-intensive, and improper shaking of the green leaves can easily cause dead green leaves, affecting the quality of black tea.

[0005] In addition, if the withering end is at night and the fan is not turned off, workers must frequently check the withering progress, otherwise it is easy to cause excessive withering. If the fan is turned off, it is easy for workers to not wither properly after work and need to wait for the withering process, resulting in work delays. This is also a problem faced by most black tea production units. Summary of the invention

[0006] In order to solve the deficiencies of the prior art, the object of the present invention is to provide a black tea withering device.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A black tea withering device comprises an upper conveyor mesh belt and a lower conveyor mesh belt with opposite conveying directions, a C-shaped elevator and a fan, a vibration transmission trough, and a far-infrared light source; the end of the lower conveyor mesh belt is connected to the C-shaped elevator through an inclined vibration transmission trough;

[0009] The fresh leaves fall from one end of the upper conveyor mesh belt to the lower conveyor mesh belt by gravity, and then fall from the other end of the lower conveyor mesh belt into the vibrating transmission trough. The fresh leaves fall into the C-type elevator through vibration, and then are returned to the upper conveyor mesh belt by the C-type elevator.

[0010] The fan is used to supply air or suck air from the bottom to the upper conveyor belt;

[0011] The far-infrared light source of the upper conveyor belt for light exposure is suspended above the upper conveyor belt.

[0012] The above-mentioned upper conveyor belt, lower conveyor belt and fan are arranged in the box body. The upper conveyor belt and the lower conveyor belt are fixed by the opposite side plates of the box body, and the fan is fixed by the end side plates of the box body.

[0013] Furthermore, weighing devices are provided on the support feet of the box body.

[0014] Still further, the above-mentioned upper conveyor belt, lower conveyor belt, C-type elevator, fan, far-infrared light source, and weighing device are respectively connected to the control device and driven by the control device;

[0015] The control device is also used to open and close the upper conveyor belt, lower conveyor belt, C-type elevator, fan, and far-infrared light source according to the feedback of the weighing device.

[0016] The beneficial effects of the present invention are as follows:

[0017] A black tea withering device of the present invention integrates infrared withering, automatic leaf turning and oscillating green-making. It uses far-infrared radiation to improve the activity of oxidase in fresh tea leaves, uses the oscillating green-making technology to promote the water movement of fresh leaves and increase the content of aroma precursor substances and the activity of related enzymes, and avoids mechanical damage caused by the traditional shaking green technology. The entire withering process does not require manual leaf turning and waiting, greatly reducing the labor intensity and reducing the labor input; the leaf turning and transportation processes of the conveyor belt and elevator do not apply pressure to the tea leaves, and also avoid mechanical damage caused by the friction between the tea leaves and the trough body; the oscillating green-making can not only promote the water movement of fresh leaves, but also avoid mechanical damage caused by the operation of the traditional shaking green machine, improving the withering quality.

[0018] A black tea withering device of the present invention processes black tea with significant effects of removing bitterness and enhancing fragrance. The content of tea polyphenols is effectively reduced, the content of theaflavins and thearubigins is increased, the tea soup is mellow, the aroma is improved, and the sensory quality of the tea is significantly improved. Moreover, the device is small, easy to use and low in cost, significantly reducing the labor cost and improving the production efficiency, and has strong practicability and wide applicability. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the black tea withering device.

[0020] The meanings of the marks in the drawings are as follows: 1. Far-infrared light source, 2. Upper conveyor belt, 3. Lower conveyor belt, 4. Vibration transmission trough, 5. Fan, 6. C-type elevator, 7. Weighing device. Detailed Embodiments

[0021] The following is a specific introduction to the present invention in combination with the drawings and specific embodiments.

[0022] Example 1

[0023] A black tea withering device is composed of an upper conveyor net belt, a lower conveyor net belt, a C-type elevator, a blower, a far-infrared light source, a weighing device and a control device.

[0024] Among them, the upper conveyor net belt, the lower conveyor net belt, the blower weighing device and the control device are arranged in the box body and are integrated.

[0025] The top and bottom of the box body are open and are composed of opposing side plates and end side plates. The upper conveyor net belt and the lower conveyor net belt are horizontally arranged in the box body and are fixed by the opposing side plates on both sides of the box body. The upper conveyor net belt and the lower conveyor net belt can be horizontally arranged or can be inclined. Preferably, at one end of the box body, the end of the lower conveyor net belt is slightly longer than the end of the upper conveyor net belt, which is convenient for the fresh leaves on the upper conveyor net belt to fall onto the lower conveyor net belt.

[0026] The transmission directions of the upper conveyor net belt and the lower conveyor net belt are opposite. An inclined vibrating transmission trough is connected to the other end of the lower conveyor net belt, the other end of the vibrating transmission trough is connected to the bottom of the C-type elevator, and the top of the C-type elevator is connected to the other end of the upper conveyor net belt. That is, the upper conveyor net belt, the lower conveyor net belt, the vibrating transmission trough and the C-type elevator form a closed-loop circular transmission. Fresh leaves are conveyed from the lower layer to the upper layer by the C-type elevator, and a leaf-turning cycle of the fresh leaves is formed.

[0027] The blower is fixed at the end of the box body and is fixed by the end side plate. The air outlet of the blower is placed in the closed box body. Preferably, it is directly opposite to the inclined vibrating transmission trough and the lower conveyor net belt. That is, the wind direction can be folded backward through the trough surface of the inclined vibrating transmission trough and guided to the bottom surface of the upper conveyor net belt, and then transmitted upward through the mesh holes of the upper conveyor net belt. The blower can rotate forward and backward to form a blowing effect and a suction effect.

[0028] The far-infrared light source is suspended above the upper conveyor net belt, and the infrared light evenly irradiates the fresh leaves on the upper conveyor net belt.

[0029] Several support feet are provided at the bottom of the box body, and a weighing device is provided at the support feet.

[0030] The upper conveyor net belt, the lower conveyor net belt, the vibrating transmission trough, the weighing device, the far-infrared light source and the C-type elevator are respectively connected to the control device and are driven to open and close by the control device.

[0031] The steps are as follows:

[0032] S1. Initial spreading of fresh leaves: Spread fresh leaves at the leaf inlet end of the upper conveyor net belt, and the thickness can be adjusted by the leaf spreading speed until the fresh leaves cover the entire trough surface.

[0033] The fresh leaves can be reciprocally transported between the upper conveyor belt and the lower conveyor belt, forming a leaf-turning effect; the total weight of the fresh leaves is displayed by the weighing device.

[0034] The moisture content of the initial fresh leaves can be measured by the staff using a moisture detector.

[0035] Start the blower. The air from the blower blows upward through the holes of the upper conveyor belt for withering treatment for 2 hours.

[0036] S2. Turn off the blower and start the upper conveyor belt, the lower conveyor belt and the C-type elevator; convey the treated fresh leaves to the lower conveyor belt, and after shaking and making green through the vibrating transfer trough, return them to the upper conveyor belt by the C-type elevator, forming a leaf-turning effect.

[0037] S3. Turn on the far-infrared light source and the blower. The radiation intensity is appropriate at 10-20w / m on the surface of the fresh leaves. Expose the fresh leaves returned to the upper conveyor belt to the light. At the same time, the blower changes to suction in the lower layer, so that the heat of the far-infrared light can pass through the upper conveyor belt. The cycle is 2 hours. 2

[0038] S4. Repeat steps S2 and S3, that is, after making green the fresh leaves through conveying and shaking once, return them to the upper conveyor belt and then expose them to the far-infrared light. The time is 2 hours.

[0039] S5. Turn off the far-infrared light source. After making green the fresh leaves through conveying and shaking and returning them to the upper conveyor belt, turn on the blower and blow air forward until the fresh leaves reach the target moisture content, then stop working.

[0040] The target moisture content can be obtained by the weighing device based on the weight before weight loss and the weight after weight loss.

[0041] Taking 25 kg of fresh leaves for initial spreading as an example, the initial moisture content of the fresh leaves is 80%, the target moisture content is 60%, and the set safety moisture content is 62% (the safety moisture content is to prevent over-withering when the personnel have not arrived).

[0042] Then, according to the following formula,

[0043]

[0044] Among them, M 末 is the target weight of the withered leaves (kg), M0 is the initial weight of the fresh leaves on the machine (kg), W0 is the initial moisture content of the fresh leaves (%), W 末 is the target moisture content of the withered leaves (%), W s is the safety moisture content of the withered leaves (%).

[0045] Then M 末 = 25 kg×(1 - 80%) / (1 - 60%) = 12.5 kg ​

[0046] Then M s =25kg×(1-80%) / (1-62%)=13.16kg

[0047] That is, when the weighing device detects that the weight of the fresh leaves on the machine has decreased to ≤13.16kg, the leaf turning cycle is stopped and the fresh leaves remain stationary on the conveyor belt.

[0048] Comparative Example 1

[0049] 6m 2 20-30kg of fresh leaves are evenly spread on the withering trough manually, and the fan is manually turned on for blowing and withering. After blowing for 2 hours, the fresh leaves are manually turned over, which takes about 15-20 minutes for one person; the blowing and withering are continued for 2-3 hours, and the fan is stopped for shaking. All the fresh leaves are loaded into the shaking machine, which is shaken for 2-5 minutes, and then the fresh leaves are taken out of the machine and evenly spread over the withering trough again. After standing for 0.5-1 hour, the fan is turned on to continue withering; after blowing and withering for 2-3 hours, the blowing is stopped and the fresh leaves are manually turned over. This cycle continues until the fresh leaves are moderately withered.

[0050] During this period, the leaves are turned over manually 3-4 times, which takes 1-1.5 hours, and the shaking operation takes about 1 hour. Since the withering process is mostly carried out at night, it is easy to cause fatigue among workers, thus affecting the withering effect; and the turning and shaking operations and their transfer process will inevitably cause mechanical damage to the fresh leaves, forming dead leaves, affecting the quality of the withered leaves; in addition, if the withering end is at night and the fan is not turned off, workers must frequently check the withering progress, otherwise it is easy to cause excessive withering. If the fan is turned off, it is easy to cause the workers to not wither properly after work and need to wait for the withering process, resulting in work delays. This is also a problem faced by most black tea production units.

[0051] The black tea prepared by treating 25 kg of fresh leaves respectively in Example 1 and Comparative Example 1 was tested, and the results are as follows:

[0052]

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A black tea withering device, characterized in that: It includes an upper conveyor mesh belt and a lower conveyor mesh belt with opposite conveying directions, a C-type elevator and a fan, a vibration transmission trough, and a far-infrared light source; The end of the lower conveyor belt is connected to the C-type elevator through an inclined vibration transmission trough; The fresh leaves fall from one end of the upper conveyor mesh belt to the lower conveyor mesh belt by gravity, and then fall from the other end of the lower conveyor mesh belt into the vibrating transmission trough. The fresh leaves fall into the C-type elevator through vibration, and then are returned to the upper conveyor mesh belt by the C-type elevator. The fan is used to supply air or suck air from the bottom to the upper conveyor belt; A far-infrared light source for exposing the upper conveyor mesh belt is suspended on the top of the upper conveyor mesh belt.

2. The withering device according to claim 1, characterized in that The upper conveyor mesh belt, the lower conveyor mesh belt and the fan are arranged in a box body, the upper conveyor mesh belt and the lower conveyor mesh belt are fixed by opposite side plates of the box body, and the fan is fixed by the end side plates of the box body.

3. The withering device according to claim 2, characterized in that The supporting feet of the box body are provided with a weighing device.

4. The withering device according to claim 3, characterized in that The upper conveyor mesh belt, the lower conveyor mesh belt, the C-shaped elevator and the fan, the far-infrared light source, and the weighing device are respectively connected to the control device and driven by the control device; The control device is also used to open and close the upper conveyor mesh belt, the lower conveyor mesh belt, the C-type elevator and the fan, and the far-infrared light source according to the feedback of the weighing device.

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