Preparation method of high-aroma black tea fresh extract

Abstract

The invention relates to a preparation method of a high-aroma black tea fresh extract. The preparation method comprises the steps of tea leaf picking, withering, crushing, fermentation, extraction, rough filtration, biological enzyme treatment, disc centrifugation, sterilization and filling. The fermented tea leaves can be directly used for producing the fresh black tea extract without drying, so that the time is saved, and the production cost is reduced; the fresh leaves are crushed and fermented, and a traditional black tea rolling post-fermentation process is not needed, so that time is saved, production efficiency is improved, and production cost is reduced; fermented fresh leaves are directly subjected to extraction, filtration, sterilization and filling, the processes are mutually connected, the tedious process that black tea is extracted after black tea is prepared originally is reduced, the storage cost is reduced, the high aroma of the tea is reserved to the maximum extent, and the quality is improved; and after the extracted tea soup is subjected to biological enzyme catalysis treatment, the clarity of the tea soup is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of tea production and processing technology, and particularly relates to a method for preparing a high-fragrance black tea fresh extract. Background Art

[0002] In the development of tea-containing products such as instant black tea powder and black tea concentrate, the price of natural high-fragrance (floral and sweet) black tea raw materials on the market is relatively high. The traditional production process of using traditional black tea leaves for instant black tea and black tea concentrate not only makes it difficult to retain the aroma, but also has extremely high production costs, and it is impossible to effectively bring high-fragrance (floral and sweet) products to the market for use in tea beverages. After continuous exploration and experimentation, it was found that such high-fragrance (floral and sweet) instant black tea powder and black tea concentrate can be directly produced from fresh leaves. After many rounds of tests, it was found that among the three products produced from this method, namely instant black tea powder, black tea concentrate and black tea fresh extract, the black tea fresh extract has a long-lasting high fragrance (floral and sweet fragrance) and the best quality. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for preparing a fresh extract of high-fragrance black tea, wherein the fermented tea leaves can be directly used in the production of the fresh extract of black tea without drying, thus saving time and reducing production costs; the fresh leaves are crushed and fermented, and there is no need for the traditional black tea rolling and fermentation process, thus saving time, improving production efficiency and reducing production costs; the fermented fresh leaves are directly extracted, filtered, sterilized and filled, and the processes are connected to each other, thus reducing the cumbersome process of extracting the black tea after the original black tea is made, reducing storage costs, retaining the high fragrance of the tea to the maximum extent and improving quality; after the extracted tea soup is treated with biological enzyme catalysis, the clarity of the tea soup is greatly improved.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing a high-fragrance black tea fresh extract, comprising the following steps: S1 Fresh leaf picking: harvesting fresh leaves of tea trees as raw materials; S2 Withering: The picked fresh leaves are evenly distributed and the withering location is ensured to be cool and dry; S3 Crushing: The withered fresh leaves are put into the crusher for crushing. The size of the leaves after crushing is required to be ≤3cm at the longest end; S4 fermentation: the crushed fresh leaves are piled up for fermentation; S5 extraction: extracting the fermented fresh leaves; S6 coarse filtration: filtering the extracted tea soup; S7 bio-enzyme treatment: the coarsely filtered tea soup is treated with bio-enzyme; S8 centrifugal separation: centrifuge the extract after the biological enzyme treatment using a disc centrifuge; S9 sterilization: sterilize the tea soup after the disc centrifuge treatment at high temperature of 125-132℃ for 10-25 seconds; S10 filling: The fresh extract after ultra-high temperature instantaneous sterilization is cooled to 30-45°C in the cooling pipeline, enters the aseptic filling machine into the composite aluminum foil aseptic bag, and obtains the high-fragrance black tea fresh extract.

[0005] In a preferred embodiment, in step S1, the proportion of fresh leaf buds and tender leaves is ≥ 80%, and the proportion of red stems and old leaves is ≤ 20.0%.

[0006] In a preferred embodiment, in step S2, the thickness of the fresh leaves is controlled within 5 cm, the withering time is 14-18 hours, the room temperature is controlled at 20-30° C., and the relative humidity is controlled at RH<70%.

[0007] In a preferred embodiment, the longest end of the blade after crushing in step S3 is ≤3 cm.

[0008] In a preferred embodiment, in step S4, the fresh leaves are stacked at a height of 10-15 cm, the fermentation time is 2-3 hours, the temperature is 25-30° C., and the relative humidity is controlled at RH>80%.

[0009] In a preferred embodiment, the extraction in step S5 uses purified water, with a tea-water ratio of 1:8, and the extraction time is 30 minutes, and the extraction water temperature is 86±2°C.

[0010] In a preferred embodiment, the mesh bag in the filtering device in step S6 has a 100-mesh opening and a pore size of 0.15 mm.

[0011] In a preferred embodiment, the biological enzymes in step S7 include cellulase, tannase and pectinase, and an enzymatic solution is obtained after treatment for 1 hour.

[0012] In a preferred embodiment, the rotation speed of the disc centrifuge in step S8 is 5000-7500 rpm, and the feed rate is controlled at 2000-2500 L / hour.

[0013] The present invention can achieve the following beneficial effects: (1) Fermented tea leaves do not need to be dried and can be directly used in the production of fresh black tea extract, saving time and reducing production costs; (2) The fresh leaves are crushed and fermented, eliminating the need for the traditional rolling and fermentation process for black tea, which saves time, improves production efficiency, and reduces production costs; (3) Extraction, filtration, sterilization and filling are carried out directly from the fermented fresh leaves. The processes are connected to each other, which reduces the cumbersome process of making black tea and then extracting black tea, reduces storage costs, retains the high fragrance of tea to the greatest extent, and improves quality; (4) After the extracted tea soup is treated with biological enzyme catalysis, the clarity of the tea soup is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 is a process flow chart of the present invention; DETAILED DESCRIPTION Embodiment 1: like Figure 1 A method for preparing a fresh extract of high-fragrance black tea comprises the following steps: S1 Fresh leaf picking: harvesting fresh leaves of tea trees as raw materials; S2 Withering: The picked fresh leaves are evenly distributed and the withering location is ensured to be cool and dry; S3 Crushing: The withered fresh leaves are put into the crusher for crushing. The size of the leaves after crushing is required to be ≤3cm at the longest end; S4 fermentation: the crushed fresh leaves are piled up for fermentation; S5 extraction: extracting the fermented fresh leaves; S6 coarse filtration: filtering the extracted tea soup; S7 bio-enzyme treatment: the coarsely filtered tea soup is treated with bio-enzyme; S8 centrifugal separation: centrifuge the extract after the biological enzyme treatment using a disc centrifuge; S9 sterilization: sterilize the tea soup after the disc centrifuge treatment at high temperature of 125-132℃ for 10-25 seconds; S10 filling: The fresh extract after ultra-high temperature instantaneous sterilization is cooled to 30-45°C in the cooling pipeline, enters the aseptic filling machine into the composite aluminum foil aseptic bag, and obtains the high-fragrance black tea fresh extract.

[0014] Embodiment 2: like Figure 1 The proportion of fresh leaf buds and young leaves is ≥ 80%; the proportion of red stems and old leaves is ≤ 20.0%; the buds and leaves are complete, and the appearance is bright green and uniform; there are no diseased leaves or insect-infested leaves; there are no fresh leaves with lignified brown-red stems.

[0015] Embodiment three: like Figure 1 The machine-picked fresh leaves are spread out indoors, and the plane thickness is controlled at 4 cm. The temperature in the withering room is controlled at 28°C, the relative humidity RH is 60-65%, and the withering time lasts for 14 hours.

[0016] Embodiment 4: like Figure 1 In the process, the fresh leaves are put into the crusher and cut into irregular pieces, and the size of the longest end of the pieces is within 3cm. The crushed fresh leaf pieces are broken up in time to avoid clumping.

[0017] Embodiment five: like Figure 1 The crushed fresh leaves were piled up at a height of 15 cm, the fermentation time was 3 h, the temperature was 28 ° C, and the relative humidity was 80%. The fermented leaves were obtained by controlling the fermentation conditions.

[0018] Embodiment six: like Figure 1 The fermented fresh leaves were extracted using an extraction tank, using purified water at a tea-water ratio of 1:8. The extraction water temperature was 86°C, and the extraction time was 30 minutes. The extract was obtained by controlling the extraction conditions.

[0019] Embodiment seven: like Figure 1 The tea soup after coarse filtration is cooled to 40°C, and tanninase (0.5% by mass of the tea soup), pectinase (0.5% by mass of the tea soup), and cellulase (0.5% by mass of the tea soup) are added for enzymolysis for 60 minutes to obtain an enzymolysis solution.

[0020] The beneficial effects of the present invention are as follows: fermented tea leaves do not need to be dried and can be directly used in the production of fresh black tea extract, thus saving time and reducing production costs; fresh leaves are crushed and fermented, and there is no need for the traditional black tea rolling and fermentation process, thus saving time, improving production efficiency and reducing production costs; extraction, filtration, sterilization and filling are directly carried out from the fermented fresh leaves, and the processes are connected to each other, thus reducing the cumbersome process of extracting black tea after the original black tea is made, reducing storage costs, retaining the high fragrance of tea to the maximum extent and improving quality; after the extracted tea soup is treated with biological enzyme catalysis, the clarity of the tea soup is greatly improved.

Claims

1. A method for preparing a fresh extract of high-fragrance black tea, characterized in that The steps include: S1 Fresh leaf picking: harvesting fresh leaves of tea trees as raw materials; S2 Withering: The picked fresh leaves are evenly distributed and the withering location is ensured to be cool and dry; S3 Crushing: The withered fresh leaves are put into the crusher for crushing. The size of the leaves after crushing is required to be ≤3cm at the longest end; S4 fermentation: the crushed fresh leaves are piled up for fermentation; S5 extraction: extracting the fermented fresh leaves; S6 coarse filtration: filtering the extracted tea soup; S7 bio-enzyme treatment: the coarsely filtered tea soup is treated with bio-enzyme; S8 centrifugal separation: centrifuge the extract after the biological enzyme treatment using a disc centrifuge; S9 sterilization: sterilize the tea soup after the disc centrifuge treatment at high temperature of 125-132℃ for 10-25 seconds; S10 filling: The fresh extract after ultra-high temperature instantaneous sterilization is cooled to 30-45°C in the cooling pipeline, enters the aseptic filling machine into the composite aluminum foil aseptic bag, and obtains the high-fragrance black tea fresh extract.

2. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: In the step S1, the proportion of fresh leaf buds and tender leaves is ≥80%, and the proportion of red stems and old leaves is ≤20.0%.

3. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: In the step S2, the thickness of the fresh leaves is controlled within 5 cm, the withering time is 14-18 hours, the room temperature is controlled at 20-30° C., and the relative humidity is controlled at RH<70%.

4. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: The longest end of the blade after being crushed in step S3 is ≤3 cm.

5. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: In the step S4, the fresh leaves are stacked at a height of 10-15 cm, the fermentation time is 2-3 hours, the temperature is 25-30° C., and the relative humidity is controlled at RH>80%.

6. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: In step S5, purified water is used for leaching, and the ratio of tea to water is 1:

8. The leaching takes 30 minutes, and the extraction water temperature is 86±2°C.

7. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: The mesh bag in the filtering device in step S6 has a mesh size of 100 and a pore size of 0.15 mm.

8. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: The biological enzymes in step S7 include cellulase, tannase and pectinase, and an enzymatic solution is obtained after treatment for 1 hour.

9. The method for preparing a high-fragrance black tea fresh extract according to claim 1, characterized in that: In step S8, the rotation speed of the disc centrifuge is 5000-7500 rpm, and the feed rate is controlled at 2000-2500 L / hour.

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