Wheat-fragrance yellow tea and processing method thereof

Abstract

The invention provides a processing method of wheat-fragrance yellow tea, which comprises the following steps: A) withering picked fresh leaves to obtain withered leaves; b) performing fixation on the withered leaves, and spreading for cooling to obtain fixation leaves; c) performing multi-stage low-temperature oxygen-enriched yellowing on the enzyme-deactivated leaves to obtain heaped-yellowed leaves; each period of time is 5-15 minutes, the temperature is 40-50 DEG C, and the oxygen content is 25-50%; d) rolling the yellowed leaves to obtain rolled leaves; and E) performing primary drying, dry heaping for yellowing and variable-temperature continuous convection drying on the rolled leaves to obtain the tea. Compared with a traditional yellow tea processing technology, the method adopts a multi-stage low-temperature oxygen-enriched yellowing and dry heaping for yellowing technology, and is characterized in that a dry and wet heaping for yellowing combined technology is used, so that the heaping for yellowing time is greatly shortened; in addition, a variable-temperature continuous convection far-infrared baking and drying technology is used, the aroma characteristic of traditional yellow tea is broken through, and the yellow tea processed by the method is rich in wheat aroma, mellow in taste and sweet in aftertaste, and has the characteristic of traditional'yellow soup and yellow leaves'.

Description

Technical Field

[0001] The invention relates to the technical field of tea, in particular to wheat-scented yellow tea and a processing method thereof. Background Art

[0002] Yellow tea, as one of the six major types of tea in China, is a lightly fermented tea with a long history and unique quality characteristics. Its characteristics are mainly reflected in the "yellow leaves and yellow soup", which is mainly due to its unique processing technology, especially the "yellowing" step. Yellow tea is mainly divided into yellow bud tea, yellow small tea and yellow large tea according to the age of fresh leaves and the size of buds and leaves. Its production process mainly includes the steps of killing green, rolling, yellowing and drying. Yellow tea is rich in tea polyphenols, amino acids, vitamins and caffeine, and has antioxidant effects, promotes digestion, improves cardiovascular health, and enhances immunity. In recent years, the market share of yellow tea in the tea market has gradually expanded, especially in the new tea market environment, which will drive the development of the yellow tea field.

[0003] In the traditional yellow tea production process, bamboo baskets are used for fire or the ground is piled up and covered with wet cloth. Although this gives yellow tea a unique quality, it may also cause the tea soup to be turbid and produce a stuffy taste. In recent years, some new yellow tea processing technologies have been proposed and patented. These new processes have improved production efficiency, shortened processing time, and reduced the occurrence of poor quality by improving processing steps and parameters on the basis of maintaining the quality characteristics of traditional yellow tea, but they still cannot meet the current situation of the industry. The current yellow tea market is highly regional, with weak product homogeneity and lack of distinct memory points. For example, Anhui yellow tea has a sweet floral fragrance, Zhejiang yellow tea has a more prominent tender corn flavor, and Sichuan yellow tea generally has a more fire-cooked flavor. In view of this situation, the market has an urgent need for a yellow tea product with a novel flavor that can serve as a new highlight in the market.

[0004] In recent years, the new tea beverage market has risen rapidly, greatly promoting the prosperity and development of the tea industry. In this wave of enthusiasm, the choice of tea bases has become increasingly rich, covering many well-known domestic teas and specialty teas with unique aromas. However, for niche teas such as yellow tea, new challenges and opportunities are faced. In order to broaden its market acceptance, yellow tea urgently needs to develop new flavors to meet consumers' increasingly diverse taste needs.

[0005] At the same time, the traditional yellow tea processing method can no longer meet the huge demand of the current market. In order to realize the industrialized production of yellow tea and improve production efficiency and product quality, it is urgent to explore a new processing technology. This new technology should not only retain the traditional charm of yellow tea, but also incorporate modern scientific and technological elements to create innovative new yellow tea products. Summary of the invention

[0006] In view of this, the present invention provides a processing method of wheat-flavored yellow tea. The process of the present invention has a strong wheat aroma, a mellow taste and a sweet aftertaste, and significantly improves the freshness of the tea.

[0007] The invention belongs to the field of tea processing, and specifically relates to a method for processing wheat-scented yellow tea, including fresh leaf picking, withering, multi-stage low-temperature oxygen-enriched yellowing, rolling, primary drying, dry yellowing, variable temperature continuous convection far-infrared baking and drying and other process flows. Compared with traditional yellow tea processing technology, the invention adopts multi-stage low-temperature oxygen-enriched yellowing and dry yellowing technology, and is characterized by using a combination of dry and wet yellowing technology, which greatly shortens the yellowing time, realizes large-scale and continuous production, and provides a reference for the field of industrial yellow tea; in addition, the variable temperature continuous convection far-infrared baking and drying technology is used to break through the aroma characteristics of traditional yellow tea. The yellow tea processed by the invention has a strong wheat aroma, a mellow and sweet taste, and has the traditional "yellow soup and yellow leaves" characteristics.

[0008] The present invention provides a method for processing wheat-flavored yellow tea, comprising the following steps:

[0009] A) withering the harvested fresh leaves to obtain withered leaves;

[0010] B) fixing the withered leaves, spreading them to cool, and obtaining fixed leaves;

[0011] C) subjecting the fixed leaves to multi-stage low-temperature oxygen-rich yellowing to obtain yellow leaves; each stage is 5 to 15 minutes, the temperature is 40 to 50° C., and the oxygen content is 25 to 50%;

[0012] D) rolling the yellow leaves to obtain rolled leaves;

[0013] E) subjecting the rolled leaves to primary drying, dry-drying and temperature-variable continuous convection drying to obtain.

[0014] The processing method of wheat-flavored yellow tea provided by the invention firstly performs fresh leaf picking: fresh leaves picked on a sunny day are selected, and the overall uniformity is above 80%.

[0015] The fresh leaves described in the present invention are one bud and two or three leaves in early May.

[0016] The fresh leaves are withered to obtain withered leaves. The present invention preferably uses a withering trough for withering. The fresh leaves are spread out for cooling and withering to a thickness of 3 to 5 cm.

[0017] The withered leaves are withered; the withered leaves are withered using a drum withering machine.

[0018] The fixing temperature of the present invention is 220-290°C, specifically 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, or 290°C.

[0019] The fixing time is 5 to 8 minutes, specifically 5 minutes, 6 minutes, 7 minutes or 8 minutes.

[0020] Fix the green leaves until the moisture content is 50% to 60%.

[0021] After killing the green leaves, spread them out to air to room temperature in time, remove the yellow leaves, and prepare for wet yellowing.

[0022] The cooling thickness is 3 to 5 minutes; the room temperature of the present invention can be 20 to 30°C.

[0023] The withered leaves are subjected to multi-stage low-temperature oxygen-rich yellowing to obtain yellow leaves. Each stage lasts for 5 to 15 minutes, the temperature is 40 to 50°C, and the oxygen content is 25 to 50%;

[0024] The multi-stage low-temperature oxygen-rich yellowing process of the present invention is a three-stage low-temperature oxygen-rich yellowing process;

[0025] More preferably, specifically:

[0026] The first period is 10 to 15 minutes, the temperature is 40 to 50°C, and the oxygen content is 25 to 30%;

[0027] The first time period may be 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, or any point value or range value between any two of the above;

[0028] The temperature may be 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, or any point value or range value between any two of the above;

[0029] The oxygen content may be 25%, 26%, 27%, 28%, 29%, 30%; or any point value or range value between any two of the above;

[0030] The second period is 8 to 10 minutes, the temperature is 40 to 50°C, the oxygen content is 30 to 40%; or any point value or range value between the above two;

[0031] The temperature may be 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, or any point value or range value between any two of the above;

[0032] The time can be 8 minutes, 9 minutes, 10 minutes; or any point value or range value between any two of the above;

[0033] The oxygen content may be 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%; or any point value or range value between any two of the above;

[0034] The third period is 5 to 8 minutes, the temperature is 40 to 50°C, the oxygen content is 40 to 50%, or any point value or range value between the above two;

[0035] The time can be 5min, 6min, 7min, 8min; or any point value or range value between any two of the above;

[0036] The temperature may be 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, or any point value or range value between any two of the above;

[0037] The oxygen content may be 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, or any point value or range value between any two of the above.

[0038] The yellowed leaves are rolled to obtain rolled leaves; preferably, after the yellowing is completed, the leaves are immediately put into a rolling machine for rolling.

[0039] The kneading parameters of the present invention include: time 0.5h-2h, temperature 23-28°C, cell destruction rate of 75-85%, and strip forming rate of more than 85%.

[0040] In one embodiment of the present invention, the temperature is 23-28°C, specifically 23°C, 24°C, 25°C, 26°C, 27°C, or 28°C.

[0041] The rolled leaves are initially dried; the initial drying of the present invention is performed using a chain plate for drying at 100-130° C., for 8-15 minutes, with a thickness of 1-3 cm and a moisture content of 18-25%.

[0042] In some specific embodiments, the initial drying temperature is 100°C, 110°C, 120°C or 130°C.

[0043] In some specific embodiments, the initial drying time is 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min, or 15 min.

[0044] In some specific embodiments, the thickness of the initial drying can be 1 cm, 2 cm or 3 cm.

[0045] The initially dried leaves are subjected to dry yellowing; the initially dried leaves are cooled to 40-50° C. and then subjected to dry yellowing, the dry yellowing time is 0.5-1.5 hours, the ambient temperature is maintained at 30-50° C., and the height is 20-50 cm.

[0046] The above-mentioned dry yellowing of the present invention is static yellowing.

[0047] In some specific methods, the dry yellowing environment temperature is maintained at 30-50°C, specifically 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, and 50°C.

[0048] The drying and yellowing time is 0.5 to 1.5 h, specifically 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h, 1.0 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, and 1.5 h.

[0049] After drying and yellowing, variable temperature continuous convection drying is carried out to obtain wheat-flavored yellow tea.

[0050] According to the present invention, the variable temperature continuous convection drying is variable temperature continuous convection far-infrared baking drying; specifically: three different temperature stages, each stage temperature is controlled at 120-180°C, time is 1-10 minutes, thickness is 1-3 cm, and moisture is 3-6%.

[0051] In some specific ways,

[0052] The temperature of the first stage is 120-130°C, and the time is 5-10 min. The specific temperatures can be 120°C, 121°C, 122°C, 123°C, 124°C, 125°C, 126°C, 127°C, 128°C, 129°C, and 130°C. The time can be 5 min, 6 min, 7 min, 8 min, 9 min, and 10 min.

[0053] The temperature of the second stage is 140-160°C, and the time is 3-5min. The specific temperature can be 140°C, 141°C, 142°C, 143°C, 144°C, 145°C, 146°C, 147°C, 148°C, 149°C, 150°C, 151°C, 152°C, 153°C, 154°C, 155°C, 156°C, 157°C, 158°C, 159°C, 160°C; the time can be 3min, 4min, or 5min.

[0054] The temperature of the third stage is 160-180°C, and the time is 1-3 minutes. The specific temperatures can be 160°C, 161°C, 162°C, 163°C, 164°C, 165°C, 166°C, 167°C, 168°C, 169°C, 170°C, 171°C, 172°C, 173°C, 174°C, 175°C, 176°C, 177°C, 178°C, 179°C, 180°C. The time can be 1 minute, 2 minutes, or 3 minutes.

[0055] After three stages, the final moisture content is between 3 and 6%.

[0056] In the scheme of the present invention, multi-stage low-temperature oxygen-enriched yellowing and variable temperature continuous convection far-infrared baking and drying technology are introduced for the first time, and combined with rolling means, to process wheat-scented yellow tea. This unique process not only retains the iconic "yellow soup and yellow leaves" characteristics of traditional yellow tea, but also gives yellow tea a unique aroma and taste. This method effectively solves the problems of traditional yellow tea's monotonous aroma and lack of distinctive characteristics, and greatly improves the product quality and memorable points. More importantly, the yellowing process proposed in this patent is efficient, time-saving, and easy to realize large-scale industrial production, which has far-reaching commercial value and practical significance for broadening the yellow tea market and promoting its development.

[0057] The invention provides a wheat-scented yellow tea, which is prepared by the preparation method described in any one of the above technical solutions.

[0058] The wheat-flavored yellow tea processing scheme proposed in the present invention breaks the limitation of traditional yellow tea processing technology, greatly shortens the time of yellowing, and greatly enriches the aroma level and taste experience of yellow tea. Compared with traditional yellow tea, through this innovative scheme, a new type of yellow tea product with unique wheat aroma is successfully launched. Its unique flavor will inject new vitality into the yellow tea market and further promote the development of the entire yellow tea industry.

[0059] The invention provides a wheat-scented yellow tea product, the raw materials of which include the wheat-scented yellow tea described in the above technical solution.

[0060] The invention comprises a wheat-fragrant yellow tea product, comprising the wheat-fragrant yellow tea.

[0061] The product can be in various forms such as loose tea leaves, tea bags, tea bags, tea powder, concentrated tea juice, instant tea, etc.

[0062] The material of the tea bag can be a degradable non-woven fabric or a type of tea well known to those skilled in the art.

[0063] Compared with similar products on the market, the tea products of the present invention have better quality. In terms of aroma and flavor, the tea products of the present invention are made through a unique process, and the aroma is more intense, complex and lasting, and the flavor is more mellow, fresh and refreshing, with a long aftertaste. For example, through sensory evaluation experiments, the tea products received higher scores from professional reviewers in terms of the intensity and persistence of the aroma, and the richness and coordination of the flavor.

[0064] The wheat-flavored yellow tea processing scheme proposed in the present invention introduces multi-stage low-temperature oxygen-enriched yellowing and variable temperature continuous convection far-infrared baking and drying technology. Compared with traditional yellow tea, the multi-stage low-temperature oxygen-enriched yellowing and variable temperature continuous convection far-infrared baking and drying technology are simultaneously applied, and the overall quality is higher than the application of a single technology. Through the innovation of yellow tea processing technology, a new type of yellow tea product with unique wheat aroma has been successfully launched, breaking the limitations of traditional yellow tea processing technology, greatly shortening the yellowing time, and greatly enriching the aroma level and taste experience of yellow tea. DETAILED DESCRIPTION

[0065] The present invention provides a wheat-flavored yellow tea and a processing method thereof. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve the same. It should be particularly noted that all similar replacements and modifications are obvious to those skilled in the art, and they all fall within the scope of protection of the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0066] It should be understood that the expression "one or more of..." includes each of the items recited after the expression individually and in various different combinations of two or more of the recited items, unless otherwise understood from the context and usage. The expression "and / or" in combination with three or more recited items should be understood to have the same meaning, unless otherwise understood from the context.

[0067] The use of the terms "comprising", "having" or "containing", including their grammatical synonyms, should generally be understood as open and non-restrictive, for example not excluding other unrecited elements or steps, unless otherwise specifically stated or otherwise understood from the context.

[0068] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0069] In this application, "at least one" means one or more, "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items.

[0070] It should be understood that the order of steps or the order in which certain actions are performed is not important as long as the present invention remains operable. In addition, two or more steps or actions may be performed simultaneously.

[0071] The use of any and all examples or exemplary language, such as "for example" or "including", herein is intended only to better illustrate the invention and does not limit the scope of the invention unless otherwise claimed. No language in this specification should be construed as indicating that any non-claimed element is essential to the practice of the invention.

[0072] In addition, the numerical ranges and parameters used to define the present invention are approximate values, and the relevant values ​​in the specific embodiments have been presented as accurately as possible. However, any numerical value inherently inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise expressly stated, it should be understood that all ranges, quantities, values ​​and percentages used in this disclosure are modified by "about". Here, "about" generally means that the actual value is within plus or minus 10%, 5%, 1% or 0.5% of a specific value or range.

[0073] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0074] Some cases are recorded in the embodiments and comparative examples of the present invention, wherein the embodiments show certain implementation modes of the present invention. However, this does not mean that the effects of the present invention can only be achieved in these cases.

[0075] In order to further illustrate the present invention, a wheat fragrant yellow tea and a processing method thereof provided by the present invention are described in detail below in conjunction with embodiments.

[0076] Embodiment 1: A method for processing wheat fragrant yellow tea, comprising the following steps

[0077] 1. Processing steps

[0078] (1) Fresh leaf picking: Select fresh leaf raw materials picked on a sunny day, one bud and one or two leaves, place them in a cooling trough and cool until the moisture content is 68%, the leaf color changes from bright green to lose its brightness, and after emitting a fresh fragrance, they are ready to be withered.

[0079] (2) Fixing: The temperature of the electromagnetic box was set at 290°C, the time was 6 min, and the moisture content of the fixed leaves was 68%.

[0080] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0081] (4) Multi-stage low-temperature oxygen-rich yellowing: The cooled leaves are transferred to the yellowing equipment. The first period is 15 minutes, the temperature is 42°C, and the oxygen content is 30%; the second period is 8 minutes, the temperature is 40°C, and the oxygen content is 35%; the third period is 5 minutes, the temperature is 45°C, and the oxygen content is 40%.

[0082] (5) Rolling: After the yellowing is completed, put it into the rolling machine for rolling immediately. The rolling environment temperature is 25°C, the time is 40 minutes, and the crushing rate reaches more than 80%.

[0083] (6) Initial drying: Use a chain dryer to dry at 120°C for 8 minutes, with a moisture content of 20%.

[0084] (7) Drying and yellowing: After drying, the temperature of the tea leaves drops to 40°C and is immediately transferred to the yellowing equipment for yellowing. The ambient temperature is set at 40°C for 30 minutes.

[0085] (8) Variable temperature continuous convection far-infrared baking drying: After the drying and yellowing is completed, far-infrared variable temperature continuous convection drying is adopted, with the first stage temperature of 120°C and the time of 8 min; the first stage temperature of 150°C and the time of 4 min; the first stage temperature of 170°C and the time of 2 min; the final moisture content is 3-4%.

[0086] Embodiment 2: A method for processing wheat-flavored yellow tea, comprising the following steps

[0087] 1. Processing steps

[0088] (1) Picking fresh leaves: Select fresh leaves picked on a sunny day, one bud and two or three leaves, place them in a cooling trough and cool until the moisture content is 65%, the leaf color changes from bright green to lose its brightness, and after emitting a delicate fragrance, they are ready to be withered.

[0089] (2) Fixing: The temperature of the electromagnetic box is set at 280°C, the time is 8 minutes, and the moisture content of the fixed leaves is 68%.

[0090] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0091] (4) Multi-stage low-temperature oxygen-rich yellowing: The cooled leaves are transferred to the yellowing equipment. The first period is 12 minutes, the temperature is 42°C, and the oxygen content is 30%; the second period is 8 minutes, the temperature is 45°C, and the oxygen content is 35%; the third period is 5 minutes, the temperature is 45°C, and the oxygen content is 45%.

[0092] (5) Rolling: After the yellowing is completed, put it into the rolling machine for rolling immediately. The rolling environment temperature is 25°C, the time is 40 minutes, and the crushing rate reaches more than 80%.

[0093] (6) Initial drying: Use a chain dryer to dry at 110°C for 12 min, with a moisture content of 21%.

[0094] (7) Drying and yellowing: After drying, the temperature of the tea leaves drops to 50°C and is immediately transferred to the yellowing equipment for yellowing. The ambient temperature is set at 42°C for 40 minutes.

[0095] (8) Variable temperature continuous convection far-infrared baking drying: After the drying and yellowing is completed, far-infrared variable temperature continuous convection drying is adopted, with the first stage temperature of 120°C and the time of 8 min; the first stage temperature of 160°C and the time of 5 min; the first stage temperature of 180°C and the time of 1 min; the final moisture content is 3-4%.

[0096] Embodiment 3: A method for processing wheat-flavored yellow tea, comprising the following steps

[0097] 1. Processing steps

[0098] (1) Fresh leaf picking: Select fresh leaf raw materials picked on a sunny day, one bud and two or three leaves, place them in a cooling trough and cool until the moisture content is 66%, the leaf color changes from bright green to lose its brightness, and after emitting a fresh fragrance, they are ready to be withered.

[0099] (2) Fixing: The temperature of the electromagnetic box was set at 280°C, the time was 5 minutes, and the moisture content of the fixing leaves was 67%.

[0100] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0101] (4) Multi-stage low-temperature oxygen-rich yellowing: The cooled leaves are transferred to the yellowing equipment. The first period is 15 minutes, the temperature is 40°C, and the oxygen content is 35%; the second period is 10 minutes, the temperature is 42°C, and the oxygen content is 40%; the third period is 6 minutes, the temperature is 42°C, and the oxygen content is 45%.

[0102] (5) Rolling: After the yellowing is completed, put it into the rolling machine for rolling immediately. The rolling environment temperature is 25°C, the time is 40 minutes, and the crushing rate reaches more than 80%.

[0103] (6) Initial drying: Use a chain dryer to dry at 130°C for 8 minutes, with a moisture content of 19%.

[0104] (7) Drying and yellowing: After drying, the temperature of the tea leaves drops to 45°C and is immediately transferred to the yellowing equipment for yellowing. The ambient temperature is set at 40°C for 60 minutes.

[0105] (8) Variable temperature continuous convection far-infrared baking drying: After the drying and yellowing is completed, far-infrared variable temperature continuous convection drying is adopted, with the first stage temperature of 130°C and the time of 5 min; the first stage temperature of 150°C and the time of 3 min; the first stage temperature of 170°C and the time of 1 min; the final moisture content is 3-4%.

[0106] Comparative Example 1: Multi-stage low-temperature oxygen-rich yellowing changed to wet yellowing

[0107] 1. Processing steps

[0108] (1) Fresh leaf picking: Select fresh leaf raw materials picked on a sunny day, one bud and one or two leaves, place them in a cooling trough and cool until the moisture content is 68%, the leaf color changes from bright green to lose its brightness, and after emitting a fresh fragrance, they are ready to be withered.

[0109] (2) Fixing: The temperature of the electromagnetic box was set at 290°C, the time was 6 min, and the moisture content of the fixed leaves was 68%.

[0110] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0111] (4) Wet and yellowing: pile up the leaves immediately to make them yellow for 2 hours, turning the pile once in between.

[0112] (5) Rolling: After the yellowing is completed, immediately put it into the rolling machine for rolling at an ambient temperature of 25°C for 40 minutes, and the crushing rate reaches more than 80%.

[0113] (6) Initial drying: Use a chain dryer to dry at 120°C for 8 minutes, with a moisture content of 20%.

[0114] (7) Drying and yellowing: After drying, the temperature of the tea leaves drops to 40°C and is immediately transferred to the yellowing equipment for yellowing. The ambient temperature is set at 40°C for 30 minutes.

[0115] (8) Variable temperature continuous convection far-infrared baking drying: After the drying and yellowing is completed, far-infrared variable temperature continuous convection drying is adopted, with the first stage temperature of 120°C and the time of 8 min; the first stage temperature of 150°C and the time of 4 min; the first stage temperature of 170°C and the time of 2 min; the final moisture content is 3-4%.

[0116] Comparative Example 2: Changing the temperature-variable continuous convection far-infrared baking drying to chain plate drying

[0117] 1. Processing steps

[0118] (1) Fresh leaf picking: Select fresh leaf raw materials picked on a sunny day, one bud and one or two leaves, place them in a cooling trough and cool until the moisture content is 68%, the leaf color changes from bright green to lose its brightness, and after emitting a fresh fragrance, they are ready to be withered.

[0119] (2) Fixing: The temperature of the electromagnetic box was set at 290°C, the time was 6 min, and the moisture content of the fixed leaves was 68%.

[0120] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0121] (4) Multi-stage low-temperature oxygen-rich yellowing: The cooled leaves are transferred to the yellowing equipment. The first period is 15 minutes, the temperature is 42°C, and the oxygen content is 30%; the second period is 8 minutes, the temperature is 40°C, and the oxygen content is 35%; the third period is 5 minutes, the temperature is 45°C, and the oxygen content is 40%.

[0122] (5) Rolling: After the yellowing is completed, immediately put it into the rolling machine for rolling at an ambient temperature of 25°C for 40 minutes, and the crushing rate reaches more than 80%.

[0123] (6) Initial drying: Use a chain dryer to dry at 120°C for 8 minutes, with a moisture content of 20%.

[0124] (7) Drying and yellowing: After drying, the temperature of the tea leaves drops to 40°C and is immediately transferred to the yellowing equipment for yellowing. The ambient temperature is set at 40°C for 30 minutes.

[0125] (8) Chain plate drying: After the drying is completed, the tea leaves are dried on chain plates at a temperature of 110°C for 12 minutes with a thickness of 1 cm. The final moisture content is 3-4%.

[0126] Comparative Example 3: Traditional yellow tea processing method

[0127] (1) Fresh leaf picking: Select fresh leaf raw materials picked on a sunny day, one bud and one or two leaves, place them in a cooling trough and cool until the moisture content is 68%, the leaf color changes from bright green to lose its brightness, and after emitting a fresh fragrance, they are ready to be withered.

[0128] (2) Fixing: The temperature of the electromagnetic box was set at 290°C, the time was 6 min, and the moisture content of the fixed leaves was 68%.

[0129] (3) Spread out to cool: Spread out the withered leaves immediately to a thickness of 2 cm and cool to room temperature.

[0130] (4) Rolling: After cooling to room temperature, immediately put it into a rolling machine for rolling at an ambient temperature of 25°C for 40 minutes, and the crushing rate reaches more than 80%.

[0131] (5) Yellowing: The rolled leaves are placed in an environment with a temperature of 40°C for yellowing for 12 hours, and are turned over every 4 hours.

[0132] (6) Initial baking: temperature 110°C, time 10 min, baking until the moisture content is 12-15%, then cooling for 30 min.

[0133] (7) Re-drying: temperature 90°C, time 20 min, drying until the moisture content is 3-4%.

[0134] Table 1 Sensory evaluation results of wheat-flavored yellow tea in Example

[0135]

[0136]

[0137] Table 2 Example Wheat Fragrance Yellow Tea Relative Aroma Activity Value

[0138]

[0139]

[0140] Table 3 Comparative Example Wheat Aroma Yellow Tea Relative Aroma Activity Value

[0141]

[0142]

[0143] The aroma data analysis of the embodiments and comparative examples shows that 2,5-dimethylpyrazine, 2-ethyl-6-methylpyrazine, 3-ethyl-2,5-dimethylpyrazine, 2-ethyl-3-methylpyrazine and 1H-pyrrole, 1-ethyl compounds are the main aroma components that constitute the characteristics of wheat aroma, and their content in the embodiments is significantly higher than that in the comparative example. This result strongly proves that the use of a multi-stage low-temperature oxygen-enriched yellowing process combined with a variable temperature continuous convection far-infrared baking and drying process is a key factor in making yellow tea with wheat aroma. In the comparative scheme, if any of the above process steps is missing or the traditional yellow tea production process is used, the ideal wheat aroma effect cannot be achieved. It can be seen that the wheat-scented yellow tea production process proposed in the present invention does have significant results.

[0144] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for processing wheat-flavored yellow tea, characterized in that: The steps include: A) withering the harvested fresh leaves to obtain withered leaves; B) fixing the withered leaves, spreading them to cool, and obtaining fixed leaves; C) subjecting the fixed leaves to multi-stage low-temperature oxygen-rich yellowing to obtain yellow leaves; each stage lasts for 5 to 15 minutes, the temperature is 40 to 50° C., and the oxygen content is 25 to 50%; D) rolling the yellow leaves to obtain rolled leaves; E) subjecting the rolled leaves to primary drying, dry-drying and temperature-variable continuous convection drying to obtain.

2. The processing method according to claim 1, characterized in that: The picking in step A) is carried out on a sunny day, and the overall uniformity is above 80%.

3. The processing method according to claim 1, characterized in that: Step B) The fixing time is 5 to 8 minutes, the fixing temperature is 220 to 290° C., the moisture content is 50% to 60%, the thickness of the cooling is 3 to 5 cm, and the cooling temperature is 20 to 30° C.

4. The processing method according to claim 1, characterized in that: The multi-stage low-temperature oxygen-rich yellowing in step C) is a three-stage low-temperature oxygen-rich yellowing; the first period is 10 to 15 minutes, the temperature is 40 to 50°C, and the oxygen content is 25 to 30%; the second period is 8 to 10 minutes, the temperature is 40 to 50°C, and the oxygen content is 30 to 40%; the third period is 5 to 8 minutes, the temperature is 40 to 50°C, and the oxygen content is 40 to 50%.

5. The processing method according to claim 1, characterized in that: The kneading parameters of step D) include: time 0.5h-2h, temperature 8-20°C, cell destruction rate of 75-85%, and strip forming rate of more than 85%.

6. The processing method according to claim 1, characterized in that: Step E) The primary drying is performed by using a chain plate, at 100-130° C., for 8-15 min, with a thickness of 1-3 cm and a moisture content of 18-25%.

7. The processing method according to claim 1, characterized in that: Step E) cooling the initially dried leaves to 40-50° C. and then drying and yellowing them. The drying and yellowing time is 0.5-1.5 hours. The ambient temperature is maintained at 30-50° C. and the height is 20-50 cm.

8. The processing method according to claim 1, characterized in that: Step E) The variable temperature continuous convection drying is variable temperature continuous convection far-infrared baking drying; specifically: three different temperature stages, each stage temperature is controlled at 120-180°C, time is 1-10 minutes, thickness is 1-3 cm, moisture is 3-6%.

9. A wheat-flavored yellow tea, characterized in that: The compound is prepared by the preparation method according to any one of claims 1 to 9.

10. A wheat-flavored yellow tea product, characterized in that: The raw materials include the wheat-scented yellow tea described in claim 9.

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