Method for making large-leaf white tea by strong light exposure method

Abstract

The invention discloses a method for making large-leaf white tea by a strong light exposure method, which comprises the following steps: S1, spreading picked large-leaf tea tree fresh leaves, and exposing for 60-300 minutes under a light source with the average illumination intensity of 3 * 10 < 4 >-1.5 * 10 < 5 > lux; s2, transferring the tea leaves exposed in the sun into a room, and spreading, wherein the spreading thickness is 3-5cm; performing air-blast withering for 1.5-4 hours, and then turning off an air blower for natural withering for 10-14 hours; piling for 2-5 hours, and then spreading for 1-3 hours; then continuing to heap for 2-5 hours; and S3, drying the indoor withered tea leaves until the water content is less than or equal to 6.0% to obtain the large-leaf white tea. The invention also discloses the large-leaf white tea prepared by the method. According to the method for making the large-leaf white tea through the strong light exposure method, the bad bitter taste and green smell of the white tea can be reduced, and the quality characteristics of being thick, mellow and sweet, having dry fruit fragrance and being high and long in flower fragrance are formed.

Description

Technical Field

[0001] The invention relates to the technical field of tea preparation technology, and in particular to a method for making large-leaf white tea by strong light exposure. Background Art

[0002] White tea, a slightly fermented tea, is a special treasure among Chinese teas. It is named because the finished tea is mostly buds, covered with white hairs, like silver and snow. White tea has the quality characteristics of complete buds and hairs, fresh fragrance, clear yellow-green soup color, and light and sweet taste. According to the China Research Institute of Industry, in 2020 alone, my country's white tea production increased by 73,500 tons, a year-on-year increase of 48.19%, and domestic sales were 62,500 tons, a year-on-year increase of 48.1%. This shows that white tea is becoming more and more popular among consumers, the market share of white tea will become larger and larger, and the market demand for high-quality white tea will also become higher and higher.

[0003] At present, many studies have borrowed the process technology of other teas to make white tea with unique quality characteristics. For example, Chen Wei, Ma Chengying and others used air-blast withering under temperature and humidity control conditions to replace natural withering, borrowed the processing technology of oolong tea, reduced the constraints of environmental factors on production, and maintained the appearance of white tea; introduced the pile green process after withering to promote the transformation of the internal quality of tea green, effectively reduced the green smell in white tea, and brought out the sweet fragrance, making the taste more mellow; adopted high-efficiency aging technology to improve the aging efficiency of white tea, reduce the time required for aging of white tea, and improve the stability of the quality of aged white tea. Huang Guozi conducted research through different withering times and drying temperatures and found that the quality of Yinghong No. 9 white tea produced when spring tea withered for 60 hours, summer and autumn tea withered for 36 hours, and the drying temperature was 70-80℃ was the best. Huang Ganghua, Li Yuanda and others studied the effects of four drying methods on the aroma quality of Yunnan white tea. The results showed that the shade-dried white tea was fragrant with a hair fragrance and took a long time to process. White tea dried in the sun and dried in the shade both have a sun-dried flavor. Dried white tea has a floral aroma, has a shorter processing cycle and is not easily affected by the environment.

[0004] As mentioned above, the quality of white tea, especially large-leaf white tea, can be improved by improving traditional techniques or borrowing techniques from other tea types. However, all of the above techniques for making white tea are strictly prohibited from being exposed to the sun, as it is believed that exposure to the sun will bring adverse factors such as green and astringent taste to white tea. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for producing large-leaf white tea by strong light exposure, which can reduce the undesirable bitter taste and green smell of white tea and form the quality characteristics of rich sweetness, dry fruit aroma and long-lasting floral aroma.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] The first aspect of the present invention provides a method for producing large-leaf white tea by strong light exposure, comprising the following steps:

[0008] S1. Spread out the fresh leaves of large-leaf tea trees and place them under an average light intensity of 3×10 4 ~1.5×10 5 Expose under a light source of lux for 60 to 300 minutes;

[0009] S2. Transfer the exposed tea leaves to the room and spread them out with a thickness of 3 to 5 cm. First, wither them with air for 1.5 to 4 hours, then turn off the air blower and wither them naturally for 10 to 14 hours. Then, pile them up for 2 to 5 hours, and then spread them out for 1 to 3 hours. Then, continue to pile them up for 2 to 5 hours.

[0010] S3. Drying the green tea leaves after indoor withering to make the moisture content ≤6.0%, thereby obtaining the large-leaf white tea.

[0011] At present, the production process of existing large-leaf white tea is similar to the manufacturing process of traditional white tea, and the quality of the white tea produced is poor, and most of them have a green and astringent taste. In addition, all the current white tea production processes are very taboo to sun exposure, because it is believed that sun exposure will bring adverse factors such as green and astringent taste to the white tea.

[0012] In the present invention, the inventor accidentally discovered in practice that strong light exposure can stimulate white tea to produce a dry fruit aroma and floral aroma. Based on this discovery, the inventor exposed the fresh leaves of large-leaf tea trees under the condition of strong sunlight in summer and autumn, and then combined with appropriate cooling, stacking and drying steps to produce large-leaf white tea with a strong and sweet taste and obvious dry fruit (plum) and orchid aroma. The principle is: in the early stage of withering, the process technology of strong sunlight exposure is used to quickly heat up the fresh leaves of tea leaves, causing high stress on cells, rapid loss of water, causing partial cell wall rupture, and rapid and short chemical changes such as enzymatic oxidation of polyphenols in buds and leaves, inducing the emission of green air in tea leaves, and the formation of floral and fruity aroma; then the process of temperature-controlled withering and stacking is used to control the loss rate of water, so that the substances contained in the tea leaves are gradually transformed, reducing the undesirable bitter taste and green air, and forming the quality characteristics of strong and sweet, dry fruit aroma and long floral aroma.

[0013] In some preferred embodiments of the present invention, in step S1, the large-leaf tea tree may be various types of large-leaf tea trees, including but not limited to Yinghong No. 9 tea tree and Yunnan large-leaf group tea tree.

[0014] In some preferred embodiments of the present invention, in step S1, when picking fresh leaves from large-leaf tea trees, the fresh leaves include single buds, one bud and one leaf, one bud and two leaves, or one bud and three leaves.

[0015] In some preferred embodiments of the present invention, in step S1, the picked fresh leaves are spread on a withering curtain or other sun drying equipment in a single layer without overlapping.

[0016] In some preferred embodiments of the present invention, in step S1, the light source is preferably sunlight, and the average light intensity needs to be controlled within 3×10 4 ~1.5×10 5 lux range, for example, 3×10 4 lux、4×10 4 lux、5×10 4 lux、6×10 4 lux、7×10 4 lux、8×10 4 lux、9×10 4 lux, 1×10 5 lux、1.1×10 5 lux、1.2×10 5 lux、1.3×10 5 lux、1.4×10 5 lux、1.5×10 5 lux, etc. This light intensity can cause the fresh tea leaves to heat up quickly, lose water quickly, and cause some cell walls to rupture. The exposure time needs to be controlled within 60 to 300 minutes, for example, it can be 60 minutes, 80 minutes, 100 minutes, 120 minutes, 150 minutes, 180 minutes, 200 minutes, 220 minutes, 250 minutes, 280 minutes, 300 minutes, etc., and more preferably 90 to 160 minutes.

[0017] During the exposure process, the leaves are preferably turned over 1 to 3 times to ensure that all parts of the leaves are fully exposed to the sun and that the leaves lose water evenly.

[0018] In some preferred embodiments of the present invention, in step S1, the ambient temperature of the drying site is preferably above 30°C, and the ground temperature is preferably above 45°C.

[0019] In some preferred embodiments of the present invention, in step S1, after being exposed to the sun, when the fresh leaves wither until the leaf surface loses its luster, the leaf color turns to light reddish brown, the leaf edges are curled up, and they feel slightly prickly, and the stems are dark green and soft, they are transferred to indoor withering.

[0020] In some preferred embodiments of the present invention, in step S2, the withering is preferably carried out in a blower withering trough; the power of the blower is 1.5-3.5 kW, for example, it can be 1.5 kW, 2 kW, 2.5 kW, 3 kW, 3.5 kW, etc.; the air volume is controlled at 80%-100%, for example, it can be 80%, 85%, 90%, 95%, 100%, etc.

[0021] In the present invention, the tea leaves exposed to the sun are first subjected to air withering, which can make the tea leaves cool quickly and lose the grass smell; and then subjected to natural withering, which can make the tea leaves lose water slowly and transform the substances in the tea leaves.

[0022] In the present invention, after natural withering, the tea leaves need to be piled up twice, that is, first piled up for 2 to 5 hours, then spread out for 1 to 3 hours, and then piled up for another 2 to 5 hours. The two piles are necessary because the functions of the piles are to control and slow down the water loss in the tea leaves and to redistribute the water in the buds and leaves. The two piles can promote the full transformation and generation of beneficial substances in the tea leaves and improve the richness and sweetness of the tea taste.

[0023] In some preferred embodiments of the present invention, in step S2, when the tea stems are wrinkled, the grass smell decreases, the dried fruit sweet aroma is obvious, and the moisture content of the withered leaves is 15% to 25%, they are transferred to a box dryer or a chain dryer for drying.

[0024] In some preferred embodiments of the present invention, in step S3, when a box-type dryer is used for drying, the thickness of the upper leaves can be controlled at 3 to 5 cm, for example, 3 cm, 3.5 cm, 4 cm, 4.5 cm, 5 cm, etc.; the drying temperature can be controlled at 75 to 80°C, for example, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, etc.; the drying time can be controlled at 45 to 90 min, for example, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, etc.

[0025] In some preferred embodiments of the present invention, in step S3, when a chain plate dryer is used for drying, a combination of primary drying and secondary drying is adopted; and after the primary drying and before the secondary drying, the primary dried tea is spread out to cool.

[0026] In some preferred embodiments of the present invention, the thickness of the leaves in the initial baking can be controlled at 3-5 cm, for example, 3 cm, 3.5 cm, 4 cm, 4.5 cm, 5 cm, etc.; the drying temperature can be controlled at 80-90°C, for example, 80°C, 82°C, 84°C, 85°C, 86°C, 88°C, 90°C, etc.; the drying time can be controlled at 13-17 min, for example, 13 min, 14 min, 15 min, 16 min, 17 min, etc.

[0027] In some preferred embodiments of the present invention, the thickness of the re-dried leaves can be controlled at 4-5 cm, for example, 4 cm, 4.5 cm, 5 cm, etc.; the drying temperature can be controlled at 70-80°C, for example, 70°C, 72°C, 74°C, 75°C, 76°C, 78°C, 80°C, etc.; the drying time can be controlled at 15-20 min, for example, 15 min, 16 min, 17 min, 18 min, 19 min, 20 min, etc.

[0028] In some preferred embodiments of the present invention, the degree of drying is moderate when the moisture content of the green tea is ≤6.0%, the stems break when they are broken, and the tea leaves become powder when they are squeezed by hand. After drying, the tea leaves are spread out to cool, screened, sorted, and packaged.

[0029] The second aspect of the present invention provides large-leaf white tea produced by the above-mentioned strong light exposure method.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] Compared with the current white tea process, the method for making large-leaf white tea by strong light exposure provided by the present invention has a special process and is simple to operate. Through the strong light exposure method, combined with withering and stacking combined processes, tea polyphenols can be rapidly and briefly enzymatically oxidized, and polyphenols in fresh tea leaves can be rapidly converted, which can not only quickly emit the bad green gas in the tea leaves, reduce the green taste and bitterness of the tea leaves, but also induce the floral and fruity aroma in the tea leaves, forming a strong, sweet, dried fruit and long floral aroma quality characteristics. In particular, the summer and summer tea of ​​Yinghong No. 9 and Yunnan large-leaf group species can be made into white tea with a significant dried fruit (plum) fragrance and orchid fragrance, and a strong, sweet taste. The resulting white tea product is of high-end quality and unique. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0034] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are all conventional methods, and the materials, reagents, etc. used are all commercially available unless otherwise specified.

[0035] Example 1

[0036] This embodiment provides a method for making Yinghong No. 9 white tea, comprising the following steps:

[0037] Step 1: Picking: Pick single buds from the top of the Yinghong No. 9 tea tree;

[0038] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.1×10 5 Dry in sunlight at about lux for 90 to 120 minutes, turning the leaves over once during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0039] Step 3: Indoor withering, using air withering trough equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, and the air withering is 3h; then the fan is turned off and the tea leaves are naturally withered for 14h, piled for 3h, spread for 1.5h, and piled for 3h; finally, the tea leaves are withered until the stems are wrinkled, the grass smell is reduced, and the dried fruit (plum) is sweet and fragrant, and then dried;

[0040] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 75°C, and dry for 45 minutes to obtain Yinghong No. 9 white tea.

[0041] Comparative Example 1

[0042] This comparative example provides a method for preparing Yinghong No. 9 white tea, comprising the following steps:

[0043] Step 1: Picking: Pick single buds from the top of the Yinghong No. 9 tea tree;

[0044] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 5h, and then the fan is turned off and the natural withering is 21.5h;

[0045] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to be 3-5 cm, use a temperature of 75°C, and dry for 45 minutes to obtain Yinghong No. 9 white tea.

[0046] The quality of the Yinghong No. 9 white tea produced in Example 1 and Comparative Example 1 was evaluated, and the results are shown in Table 1.

[0047] Table 1 Quality evaluation results of Yinghong No. 9 single bud white tea with different processing techniques

[0048]

[0049]

[0050] Please refer to Table 1. Compared with Example 1, in the process of making Yinghong No. 9 white tea, Comparative Example 1 did not use strong light exposure, and did not use the stacking process during indoor withering. From the results, the Yinghong No. 9 white tea made in Comparative Example 1 is inferior to the Yinghong No. 9 white tea made in Example 1 in terms of appearance, soup color, leaf bottom scores, aroma, and taste. This shows that the present invention adopts the method of strong light exposure, combined with temperature-controlled withering and stacking combined processes, to produce white tea with significant fruity aroma and rich and sweet taste.

[0051] Example 2

[0052] This embodiment provides a method for making Yunnan large-leaf group white tea, comprising the following steps:

[0053] Step 1: Picking: picking single buds from the tops of Yunnan large-leaf tea trees;

[0054] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.1×10 5 Dry in sunlight at about lux for 90 to 120 minutes, turning the leaves over once during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0055] Step 3: Indoor withering, using air withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the air withering is 3h, then the fan is turned off and the natural withering is 14h, the green tea is piled for 3h, spread out for 1.5h, and then piled for 3h; finally, the green tea is withered until the stems are wrinkled, the grass smell is reduced, and the dried fruit (plum) is sweet and fragrant, and then dried;

[0056] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 75°C, and dry for 45 minutes to obtain Yunnan large-leaf group white tea.

[0057] Comparative Example 2

[0058] This comparative example provides a method for preparing Yunnan large-leaf group white tea, comprising the following steps:

[0059] Step 1: Picking: picking single buds from the tops of Yunnan large-leaf tea trees;

[0060] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 5h, and then the fan is turned off and the natural withering is 21.5h;

[0061] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 75°C, and dry for 45 minutes to obtain Yunnan large-leaf group white tea.

[0062] The quality of the Yunnan large-leaf group white tea produced in Example 2 and Comparative Example 2 was evaluated, and the results are shown in Table 2.

[0063] Table 2 Quality evaluation results of Yunnan large-leaf group single bud white tea with different processing techniques

[0064]

[0065] Please refer to Table 2. In the process of making Yunnan large-leaf group white tea, Comparative Example 2 did not expose the tea to strong light, and did not use the stacking combination process during indoor withering. Therefore, the Yunnan large-leaf group white tea obtained was inferior to the Yunnan large-leaf group white tea produced in Example 2 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0066] Example 3

[0067] This embodiment provides a method for making Yinghong No. 9 white tea, comprising the following steps:

[0068] Step 1: Picking: Pick one fresh bud and one leaf from the top of the Yinghong No. 9 tea tree;

[0069] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.1×10 5 Dry in sunlight at about lux for 100 to 130 minutes, turning the leaves over once during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0070] Step 3: Indoor withering, using air-blast withering trough equipment, with a blower power of 1.5kw and an air volume of 100%; spreading thickness at 3cm, withering for 2.5h, then turning off the blower for natural withering for 12h, piling for 3h, spreading for 2h, and piling for another 3h; finally, the tea leaves are withered until the stems shrink and turn red-brown, the grass smell subsides, and the sweet aroma of dried fruits is apparent before drying;

[0071] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to be 3-5 cm, use a temperature of 75°C, and bake for 60 minutes to obtain Yinghong No. 9 white tea.

[0072] Comparative Example 3

[0073] This comparative example provides a method for preparing Yinghong No. 9 white tea, comprising the following steps:

[0074] Step 1: Picking: Pick one fresh bud and one leaf from the top of the Yinghong No. 9 tea tree;

[0075] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 4.5h, then the fan is turned off and the natural withering is 20h, and then drying is carried out;

[0076] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to be 3-5 cm, use a temperature of 75°C, and dry for 60 minutes to obtain Yinghong No. 9 white tea.

[0077] The quality of the Yinghong No. 9 white tea produced in Example 3 and Comparative Example 3 was evaluated, and the results are shown in Table 3.

[0078] Table 3 Quality evaluation results of Yinghong No. 9 one bud one leaf white tea with different processing methods

[0079]

[0080] Please refer to Table 3. In the process of making Yinghong No. 9 white tea, since Comparative Example 3 was not exposed to strong light and the stacking process was not adopted during indoor withering, the Yinghong No. 9 white tea obtained was inferior to the Yinghong No. 9 white tea produced in Example 3 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0081] Example 4

[0082] This embodiment provides a method for making Yunnan large-leaf group white tea, comprising the following steps:

[0083] Step 1: Picking: Pick one fresh bud and one leaf from the top of the Yunnan large-leaf tea tree;

[0084] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.1×10 5 Dry in sunlight at about lux for 100 to 130 minutes, turning the leaves over once during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0085] Step 3: Indoor withering, using air-blast withering trough equipment, with a blower power of 1.5kw and an air volume of 100%; spreading thickness at 3cm, withering for 2.5h, then turning off the blower for natural withering for 12h, piling for 3h, spreading for 2h, and piling for another 3h; finally, the tea leaves are withered until the stems shrink and turn red-brown, the grass smell subsides, and the sweet aroma of dried fruits is apparent before drying;

[0086] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 75°C, and dry for 60 minutes to obtain Yunnan large-leaf group white tea.

[0087] Comparative Example 4

[0088] This comparative example provides a method for preparing Yunnan large-leaf group white tea, comprising the following steps:

[0089] Step 1: Picking: Pick one fresh bud and one leaf from the top of the Yunnan large-leaf tea tree;

[0090] Step 2: Indoor withering, using air-blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%. The thickness is 3cm, the air-blast withering is 4.5h, then the blower is turned off and the withering is carried out naturally for 20h, and then dried;

[0091] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 75°C, and dry for 60 minutes to obtain Yunnan large-leaf group white tea.

[0092] The quality of the Yunnan large-leaf group white tea produced in Example 4 and Comparative Example 4 was evaluated, and the results are shown in Table 4.

[0093] Table 4 Quality evaluation results of Yunnan large-leaf white tea with one bud and one leaf and different processing techniques

[0094]

[0095] Please refer to Table 4. In the process of making Yunnan large-leaf group white tea, Comparative Example 4 did not expose the tea to strong light, and did not use the stacking combination process during indoor withering. Therefore, the Yunnan large-leaf group white tea obtained was inferior to the Yunnan large-leaf group white tea produced in Example 4 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0096] Example 5

[0097] This embodiment provides a method for making Yinghong No. 9 white tea, comprising the following steps:

[0098] Step 1: Picking: Pick one bud and two leaves from the top of the Yinghong No. 9 tea tree;

[0099] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.3×10 5 Dry under sunlight of about lux for 120 to 150 minutes, turning the leaves over twice during the drying process to make the fresh leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems are still green;

[0100] Step 3: Indoor withering, using air-blast withering trough equipment, with a blower power of 1.5kw and an air volume of 100%; spreading thickness at 3cm, withering for 3h, then turning off the blower for natural withering for 14h, piling for 3h, spreading for 2h, and piling for another 3h; finally, the tea leaves are withered until the stems shrink and turn red-brown, the grass smell subsides, and the sweet aroma of dried fruits is apparent before drying;

[0101] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to be 3-5 cm, use a temperature of 80°C, and dry for 60 minutes to obtain Yinghong No. 9 white tea.

[0102] Comparative Example 5

[0103] This comparative example provides a method for preparing Yinghong No. 9 white tea, comprising the following steps:

[0104] Step 1: Picking: Pick one bud and two leaves from the top of the Yinghong No. 9 tea tree;

[0105] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 5.5h, and then the fan is turned off to wither naturally for 20h before drying;

[0106] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to be 3-5 cm, use a temperature of 80°C, and dry for 60 minutes to obtain Yinghong No. 9 white tea.

[0107] The quality of the Yinghong No. 9 white tea produced in Example 5 and Comparative Example 5 was evaluated, and the results are shown in Table 5.

[0108] Table 5 Quality evaluation results of Yinghong No. 9 one bud two leaves white tea with different processing techniques

[0109]

[0110] Please refer to Table 5. In the process of making Yinghong No. 9 white tea, since Comparative Example 5 was not exposed to strong light and the stacking process was not adopted during indoor withering, the Yinghong No. 9 white tea obtained was inferior to the Yinghong No. 9 white tea produced in Example 5 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0111] Example 6

[0112] This embodiment provides a method for making Yunnan large-leaf group white tea, comprising the following steps:

[0113] Step 1: Picking: Pick one bud and two leaves from the top of the Yunnan large-leaf tea tree;

[0114] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.3×10 5 Dry under sunlight of about lux for 120 to 150 minutes, turning the leaves over twice during the drying process to make the fresh leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems are still green;

[0115] Step 3: Indoor withering, using air-blast withering trough equipment, with a blower power of 1.5kw and an air volume of 100%; spreading thickness at 3cm, withering for 3h, then turning off the blower for natural withering for 14h, piling for 3h, spreading for 2h, and piling for another 3h; finally, the tea leaves are withered until the stems shrink and turn red-brown, the grass smell subsides, and the sweet aroma of dried fruits is apparent before drying;

[0116] Step 4: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 80°C, and dry for 60 minutes to obtain Yunnan large-leaf group white tea.

[0117] Comparative Example 6

[0118] This comparative example provides a method for preparing Yunnan large-leaf group white tea, comprising the following steps:

[0119] Step 1: Picking: Pick one bud and two leaves from the top of the Yunnan large-leaf tea tree;

[0120] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 1.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 5.5h, and then the fan is turned off to wither naturally for 20h before drying;

[0121] Step 3: Drying: Use a box-type dryer to dry the leaves, control the thickness of the upper leaves to 3-5 cm, use a temperature of 80°C, and dry for 60 minutes to obtain Yunnan large-leaf group white tea.

[0122] The quality of the Yunnan large-leaf group white tea produced in Example 6 and Comparative Example 6 was evaluated, and the results are shown in Table 6.

[0123] Table 6 Quality evaluation results of Yunnan large-leaf white tea with one bud and two leaves and different processing techniques

[0124]

[0125] Please refer to Table 6. In the process of making Yunnan large-leaf group white tea, Comparative Example 6 did not expose the tea to strong light, and did not adopt the stacking combination process during indoor withering. Therefore, the Yunnan large-leaf group white tea obtained was inferior to the Yunnan large-leaf group white tea produced in Example 6 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0126] Example 7

[0127] This embodiment provides a method for making Yinghong No. 9 white tea, comprising the following steps:

[0128] Step 1: Pick the fresh one bud and three leaves from the top of the Yinghong No. 9 tea tree;

[0129] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.2×10 5 Dry in sunlight at about lux for 140 to 160 minutes, turning the leaves over twice during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0130] Step 3: Indoor withering, using air-blast withering trough equipment, the blower power is 3.5kw, the air volume is 100%; the thickness is 3cm, the air-blast withering is 4h, then the blower is turned off and withered naturally for 10h, the green tea is piled for 4.5h, spread out for 2.5h, and piled for another 4h; finally, the green tea is withered until the stems are wrinkled and reddish brown, the grass smell is reduced, and the sweet fragrance of dried fruits is obvious, then it is dried;

[0131] Step 4: Drying: Use a chain plate dryer for drying. The thickness of the leaves in the initial drying is controlled at 3-5 cm, and the temperature is 90°C for 17 minutes. The thickness of the leaves in the re-drying is controlled at 4-5 cm, and the temperature is 80°C for 20 minutes to obtain Yinghong No. 9 white tea.

[0132] Comparative Example 7

[0133] This comparative example provides a method for preparing Yinghong No. 9 white tea, comprising the following steps:

[0134] Step 1: Pick the fresh one bud and three leaves from the top of the Yinghong No. 9 tea tree;

[0135] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 3.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 6.5h, and then the fan is turned off to naturally wither for 21h before drying;

[0136] Step 3: Drying: Use a chain plate dryer for drying. The thickness of the leaves in the initial drying is controlled at 3-5 cm, and the temperature is 90°C for 17 minutes. The thickness of the leaves in the re-drying is controlled at 4-5 cm, and the temperature is 80°C for 20 minutes to obtain Yinghong No. 9 white tea.

[0137] The quality of the Yinghong No. 9 white tea produced in Example 7 and Comparative Example 7 was evaluated, and the results are shown in Table 7.

[0138] Table 7 Quality evaluation results of Yinghong No. 9 one bud three leaves white tea with different processing techniques

[0139]

[0140] Please refer to Table 7. In the process of making Yinghong No. 9 white tea, Comparative Example 7 did not expose the tea to strong light, and did not use the stacking process during indoor withering. Therefore, the Yinghong No. 9 white tea obtained was inferior to the Yinghong No. 9 white tea produced in Example 7 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0141] Example 8

[0142] This embodiment provides a method for making Yunnan large-leaf group white tea, comprising the following steps:

[0143] Step 1: Picking: Pick the fresh one bud and three leaves from the top of the Yunnan large-leaf tea tree;

[0144] Step 2: Drying: Spread the fresh leaves on the withering curtain in a single layer without overlapping. Place the leaves under an average light intensity of 1.2×10 5 Dry in sunlight at about lux for 140 to 160 minutes, turning the leaves over twice during the drying process to ensure that the leaves lose water evenly; transfer to indoor withering after the leaves lose their luster and turn reddish brown, while the stems remain green;

[0145] Step 3: Indoor withering, using air-blast withering trough equipment, the blower power is 3.5kw, the air volume is 100%; the thickness is 3cm, the air-blast withering is 4h, then the blower is turned off and withered naturally for 10h, the green tea is piled for 4.5h, spread out for 2.5h, and piled for another 4h; finally, the green tea is withered until the stems are wrinkled and reddish brown, the grass smell is reduced, and the sweet fragrance of dried fruits is obvious, then it is dried;

[0146] Step 4: Drying: use a chain plate dryer for drying. The thickness of the leaves in the initial drying is controlled at 3-5 cm, and the temperature is 90°C and the drying time is 17 minutes. The thickness of the leaves in the re-drying is controlled at 4-5 cm, and the temperature is 80°C and the drying time is 20 minutes to obtain Yunnan large-leaf group white tea.

[0147] Comparative Example 8

[0148] This comparative example provides a method for preparing Yunnan large-leaf group white tea, comprising the following steps:

[0149] Step 1: Picking: Pick the fresh one bud and three leaves from the top of the Yunnan large-leaf tea tree;

[0150] Step 2: Indoor withering, using a blast withering tank equipment, the blower power is 3.5kw, the air volume is 100%; the thickness is 3cm, the blast withering is 6.5h, and then the fan is turned off to naturally wither for 21h before drying;

[0151] Step 3: Drying: Use a chain plate dryer for drying. The thickness of the leaves in the initial drying is controlled at 3-5 cm, and the temperature is 90°C for 17 minutes. The thickness of the leaves in the re-drying is controlled at 4-5 cm, and the temperature is 80°C for 20 minutes to obtain Yunnan large-leaf group white tea.

[0152] The quality of the Yunnan large-leaf group white tea produced in Example 8 and Comparative Example 8 was evaluated, and the results are shown in Table 8.

[0153] Table 8 Quality evaluation results of Yunnan large-leaf group white tea with one bud and three leaves and different processing methods

[0154]

[0155]

[0156] Please refer to Table 8. In the process of making Yunnan large-leaf group white tea, Comparative Example 8 did not expose the tea to strong light, and did not adopt the stacking combination process during indoor withering. Therefore, the Yunnan large-leaf group white tea obtained was inferior to the Yunnan large-leaf group white tea produced in Example 8 in terms of appearance, soup color, leaf bottom, aroma and taste.

[0157] In summary, the method for making large-leaf white tea by strong light exposure provided by the present invention can quickly transform polyphenols in fresh tea leaves through strong light exposure, reduce the green taste and bitterness of tea leaves, and especially can make summer and summer tea of ​​Yinghong No. 9 and Yunnan large-leaf group species into white tea with obvious dried fruit (plum) and orchid fragrance, rich and sweet taste. The white tea product produced is of high-end quality and unique.

[0158] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A method for producing large-leaf white tea by strong light exposure, characterized in that: The following steps are involved: S1. Spread out the fresh leaves of large-leaf tea trees and place them under an average light intensity of 3×10 4 ~1.5×10 5 Expose under a light source of lux for 60 to 300 minutes; S2. Transfer the exposed tea leaves to the room and spread them out with a thickness of 3 to 5 cm. First, wither them with air for 1.5 to 4 hours, then turn off the air blower and wither them naturally for 10 to 14 hours. Then, pile them up for 2 to 5 hours, and then spread them out for 1 to 3 hours. Then, continue to pile them up for 2 to 5 hours. S3. Drying the green tea leaves after indoor withering to make their moisture content ≤6.0%, thereby obtaining the large-leaf white tea.

2. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S1, the large-leaf tea tree includes Yinghong No. 9 tea tree and Yunnan large-leaf group tea tree; The fresh leaves include single bud, one bud and one leaf, one bud and two leaves, and one bud and three leaves.

3. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S1, the picked fresh leaves are spread on a withering curtain or other drying equipment in a single layer without overlapping.

4. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S1, the light source is sunlight, and the clothes are turned over 1 to 3 times during the exposure process.

5. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S1, after being exposed to the sun, when the fresh leaves wither until the leaf surface loses its luster, the leaf color turns to light reddish brown, the leaf edges are raised, and there is a slight prickly feel, and the stems are dark green and soft, they are transferred to a room for withering.

6. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S2, the withering is carried out in a blast withering tank, the power of the blower is 1.5-3.5 kW, and the air volume is 80%-100%.

7. The method for producing large-leaf white tea by strong light exposure according to claim 1, characterized in that: In step S2, when the tea stems are wrinkled and the moisture content of the withered leaves is between 15% and 25%, they are transferred to a box dryer or a chain plate dryer for drying.

8. The method for producing large-leaf white tea by strong light exposure according to claim 7, characterized in that: In step S3, when a box-type dryer is used for drying, the thickness of the upper leaves is controlled at 3 to 5 cm, the drying temperature is controlled at 75 to 80° C., and the drying time is controlled at 45 to 90 min.

9. The method for producing large-leaf white tea by strong light exposure according to claim 7, characterized in that: When a chain plate dryer is used for drying, a combination of primary drying and secondary drying is used; and after the primary drying and before the secondary drying, the tea leaves are spread out to cool; The thickness of the leaves in the initial drying is controlled at 3-5 cm, the drying temperature is controlled at 80-90°C, and the drying time is controlled at 13-17 minutes; The thickness of the leaves on the double drying is controlled at 4-5 cm, the drying temperature is controlled at 70-80°C, and the drying time is controlled at 15-20 minutes.

10. Large-leaf white tea produced according to the method of any one of claims 1 to 9.

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