Mechanical processing method of lichun red beads

Abstract

The application discloses a mechanical processing method of pearl-shaped Lichuan Hong tea, which comprises the steps of picking fresh leaves, withering, rolling, fermentation, circulating frying, alcoholization, shaping, setting, drying and aroma enhancement. The circulating frying technology is adopted to avoid the defect that the drier can only dehydrate but cannot shape. The pearl tea frying machine can shape in a short time. The leaves shaped by the machine can be fixed in shape at room temperature by a pressing and rolling machine. The application effectively guarantees the taste quality of the pearl-shaped Lichuan Hong tea. On one hand, the frying time is shortened. On the other hand, a unique alcoholization process is invented to promote the hydrolysis of protein and polysaccharide into amino acid and soluble sugar and promote the formation of alcohol and taste. The application has the advantages of high degree of mechanization, controllable process parameters, stable tea making quality, simple operation, low cost, etc. The cost of the pearl-shaped Lichuan Hong tea prepared by the application is reduced by more than 30% compared with traditional products, and the price is increased by more than 30%.

Description

Technical Field

[0001] This invention belongs to the field of tea-making technology, specifically relating to a mechanized processing method for bead-shaped Lichuan red tea. Background Technology

[0002] Lichuan Red is a famous and high-quality black tea developed in Lichuan City. For a long time, it has been mainly produced in strip form, with few product varieties, which is not conducive to market promotion. The basic processing steps of Lichuan Red are withering-rolling-fermentation-drying. The specific process of each step will directly affect the formation of tea quality. Non-patent literature (Luo Xueping et al., The Influence of Different Shaping Processes on the Quality of Granular Black Tea, Guizhou Agricultural Sciences 2016, 44(2): 152-155) proposed a shaping process for granular black tea: wrapping and rolling → wrapping and rolling → curling or wrapping and rolling → wrapping and rolling. This process can only form irregular granules and cannot form beads. Patent literature (CN201510942096.8) reported a bead-shaped black tea process: withering-rolling-fermentation-dehydration-shaping-drying-enhancing. The shape is processed into beads, but the forming time is too long and the processing quality needs to be improved. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, the purpose of this invention is to provide a mechanized processing method for pearl-shaped Lichuan red tea. This method is simple and easy to implement, and the resulting product achieves the quality of "dry tea that is tightly round and pearl-shaped, with a dark and lustrous color, a bright red liquor, a sweet floral and fruity aroma, a fresh and mellow taste, and a bright red leaf base". The product has distinct characteristics and improves the economic utilization value of tea.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0005] A mechanized processing method for pearl-shaped Lichuan red apricots includes fresh leaf picking, as well as withering, rolling, fermentation, drying, shaping, aging, setting, drying, and aroma enhancement steps, specifically including the following steps:

[0006] (1) Variety selection: Select any one of the excellent varieties such as Echa No. 10, Lenghouhun, and Huahong No. 1;

[0007] (2) Fresh leaf picking: The standard is one bud and two or three leaves. The leaves are picked by hand, without squeezing or damaging them.

[0008] (3) Withering: Withering troughs or automatic withering machines can be used. The thickness of the spread leaves is 10cm-15cm, the withering time is 8h-12h, and the degree of withering is appropriate when the moisture content of the buds and leaves is 55%-58% to obtain withered leaves;

[0009] (4) Rolling: After the withered leaves are rehydrated for 30-50 minutes, they are rolled using a 6CR-55 tea rolling machine for 100-120 minutes. After rolling, the leaves are broken up to obtain rolled leaves.

[0010] (5) Fermentation: The rolled leaves are processed using a black tea fermentation machine. The fermentation temperature is around 35℃, the air humidity is above 90%, and the time is 4.5h-5.0h. The leaves are fermented until they turn yellow-red to obtain fermented leaves.

[0011] (6) Harvesting: Fermented leaves are harvested using a fragrant tea drying machine at a temperature of 200-220℃ and a tea moisture content of 35%-39% to obtain harvested leaves;

[0012] (7) Shaping: The leaves are dried using a pearl tea drying machine, and the shaping is done in two stages. First shaping: temperature 170℃~190℃, time 20min~25min, tea moisture content 20%~25%. Second shaping: The leaves from the first shaping are separated into sieves using a round sieve machine with a sieve size of 0.85cm~1.00cm. The sieve-over tea and sieve-under tea are separated. The sieve-under tea can directly enter the shaping process, while the sieve-over tea undergoes the second shaping. Temperature 150℃~170℃, time 20min~25min, tea moisture content 12%~15%, resulting in shaped leaves.

[0013] (8) Methanol infusion: The shaped leaves are directly fed into the ethanol infusion machine without cooling, and the leaf temperature is maintained at 40-45℃ for 30 minutes to obtain ethanol-infused leaves;

[0014] (9) Shaping: The leaves are not cooled before being shaped by a kneading machine for 5 to 10 minutes to obtain shaped leaves;

[0015] (10) Drying: Drying is performed in two stages. The first stage involves shaping the leaves without cooling them. A chain plate dryer or aroma-enhancing machine is used for rapid initial drying at 110-120℃ for 5-10 minutes, until the moisture content of the tea leaves is 8-10%. The initially dried leaves are then rapidly re-dried using a chain plate dryer or aroma-enhancing machine at 80-90℃ until the moisture content of the tea leaves is controlled below 7%. The dried leaves are then obtained.

[0016] (11) Aroma Enhancement: After cooling the dried leaves, rehydrate them for 1-2 hours. Use a chain plate dryer or aroma enhancer to enhance the aroma at a temperature of 115-120℃ and a leaf thickness of 1-2.5cm. Dry until the tea has a sweet aroma, and then obtain the finished tea.

[0017] Preferably, in step (8): the first shaping temperature is 170℃-190℃ and the time is 20min-25min, resulting in tea leaves with a moisture content of 20%-25%; the second shaping: the leaves obtained from the first shaping are separated into sieve tea and sieve tea using a round sieve machine with a sieve size of 0.85cm-1.00cm. The sieve tea directly enters the shaping process, while the sieve tea undergoes a second shaping: the temperature is 150℃-170℃ and the time is 20min-25min, resulting in shaped leaves with a moisture content of 12%-15%.

[0018] Preferably, in step (10), the first drying of the shaped leaves is not cooled, and a chain plate dryer or aroma enhancer is used for rapid initial drying at a temperature of 110-120℃ for 5-10 minutes until the moisture content of the tea leaves is 8-10%. The resulting initial dried leaves are then rapidly re-dried using a chain plate dryer or aroma enhancer at a temperature of 80-90℃ until the moisture content of the tea leaves is controlled within 7%.

[0019] Preferably, in step (7), the optimal simmering time is 30 min.

[0020] Compared with the prior art, the present invention has the following significant advantages:

[0021] 1. The process of this invention improves the appearance quality of pearl-shaped black tea: the fermented leaves are processed using a rolling technique, which avoids the defect of dryers that only dehydrate without shaping. After rolling, the tea leaves are initially curled, and can be shaped quickly using a pearl tea drying machine. The shaped leaves can then be pressed and kneaded at room temperature to fix their shape.

[0022] 2. The process of this invention effectively guarantees the flavor and quality of pearl-shaped black tea: Previous shaping processes involved prolonged frying using a dryer, resulting in a bitter and astringent taste in the black tea. This invention shortens the frying time and incorporates a unique mellowing process that promotes the hydrolysis of proteins and polysaccharides into amino acids and soluble sugars, thus fostering the formation of a mellow and flavorful taste.

[0023] 3. Due to the high degree of mechanization, controllable process parameters, stable tea quality, and simple operation of the present invention, the cost is low. The pearl-shaped black tea produced using the technology of the present invention has a cost reduction of more than 30% and a price increase of more than 30% compared with traditional products. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments. Unless otherwise specified, the technical solutions described in this invention are conventional solutions in the art, and the reagents or materials described are all derived from commercial sources.

[0025] Example 1:

[0026] A mechanized processing method for pearl-shaped black tea includes the following steps:

[0027] (1) Variety selection: Select Echa No. 10;

[0028] (2) Fresh leaf picking: The standard is one bud and three leaves, picked by hand, without squeezing or damaging the fresh leaves during picking;

[0029] (3) Withering: A 6CDCWD-100 type withering machine can be used. The leaf thickness is 13cm, the withering time is 12h, and the degree of withering is appropriate when the moisture content of the buds and leaves is 58% to obtain withered leaves;

[0030] (4) Rolling: After the withered leaves are rehydrated for 30-50 minutes, they are rolled using a 6CR-55 tea rolling machine for 120 minutes. After rolling, the leaves are broken up to obtain rolled leaves.

[0031] (5) Fermentation: The rolled leaves are processed using a 6CFJ-100 black tea fermentation machine. The fermentation temperature is about 35℃, the air humidity is above 90%, and the time is 5.0h. The leaves are fermented until they turn yellow-red to obtain fermented leaves.

[0032] (6) Harvesting: The fermented leaves are harvested using a 6CXC-110 type fragrant tea drying machine at a temperature of 220℃ and a tea moisture content of 38% to obtain harvested leaves.

[0033] (7) Shaping: The tea leaves are dried using a 6CSG-50 pearl tea drying machine, and the shaping is done in two stages. First shaping: temperature 180℃, time 23min, tea moisture content 25%. Second shaping: The leaves from the first shaping are separated into over-sieve tea and under-sieve tea using a 6CYS-80 circular sieve machine with a 0.9cm sieve. The under-sieve tea can directly enter the shaping process, while the over-sieve tea undergoes the second shaping. Temperature 160℃, time 24min, tea moisture content 15%, resulting in shaped leaves;

[0034] (8) Methanol treatment: The shaped blades are directly fed into a 6CM-80 type molten metal press without cooling, and the blade temperature is maintained at 43℃ for 30 minutes to obtain molten blades.

[0035] (9) Shaping: The leaves are shaped without being cooled, using a 6CYR-85 press and kneading machine for 9 minutes to obtain shaped leaves;

[0036] (10) Drying: Drying is performed in two stages. The first stage involves shaping the leaves without cooling them. A 6CH-10 type chain plate dryer is used for rapid initial drying at 110℃ for 10 minutes, until the moisture content of the tea leaves reaches 10%. The initially dried leaves are then rapidly re-dried using a 6CH-10 type chain plate dryer at 90℃ until the moisture content of the tea leaves is controlled below 7%. The dried leaves are obtained.

[0037] (11) Aroma enhancement: After cooling the dried leaves, rehydrate them for 2 hours. Use a 6CH-10 type chain plate dryer to enhance the aroma at a temperature of 120℃ and a leaf thickness of 2.0cm. Dry until the tea leaves have a sweet aroma, and then obtain the finished tea.

[0038] Example 2:

[0039] The impact of receipts on the quality of pearl-shaped black tea. This includes the following steps:

[0040] Comparative Example 2 is the same as Example 1 in terms of process, except that step (6) is replaced with a traditional dryer initial drying method. The other implementation steps are the same as in Example 1.

[0041] Experimental results show that, compared with traditional hot air drying, the pearl-shaped tea processed by strip drying has a tighter, curlier, and more uniform appearance, and its quality is significantly improved.

[0042] Table 1. The Influence of Receipts on the Sensory Quality of Pearl-shaped Lichuan Red Tea

[0043]

[0044] Note: Fresh leaves were harvested on April 25, 2023; the full score for each item in the table is 100, and the weighted score is calculated based on appearance (30%), liquor color (10%), aroma (25%), taste (25%), and leaf residue (10%); the data are the mean ± standard deviation of three replicates. Different uppercase letters in the same column indicate extremely significant differences at the p < 0.01 level, and lowercase letters indicate significant differences at the p < 0.05 level.

[0045] Example 3:

[0046] The effect of aging on the quality of pearl-shaped black tea. This includes the following steps:

[0047] Choose Huahong No. 1, with the standard for fresh leaves being one bud and three leaves;

[0048] A 6CDCWD-100 wilting machine was used, with a leaf thickness of 15cm and a wilting time of 12 hours. The degree of wilting was such that the moisture content of the buds and leaves was 57%, resulting in wilted leaves.

[0049] After rehydrating the withered leaves for 30-50 minutes, roll them using a 6CR-55 tea rolling machine for 120 minutes. After rolling, break up the clumps to obtain rolled leaves.

[0050] The rolled leaves were processed using a 6CFJ-100 black tea fermentation machine at a temperature of about 33℃ and an air humidity of over 95% for 4.6 hours, until the leaves turned yellowish-red, thus obtaining fermented leaves.

[0051] Fermented leaves were collected using a 6CXC-110 type fragrant tea drying machine at a temperature of 210℃ and a tea moisture content of 36% to obtain collected leaves.

[0052] The tea leaves are processed using a 6CSG-50 pearl tea drying machine, with two shaping steps. First shaping: temperature 180℃, time 23 minutes, tea moisture content 25%. Second shaping: The leaves from the first shaping are separated into over-sieve tea and under-sieve tea using a 6CYS-80 circular sieve machine with a 1.0cm sieve. The under-sieve tea can directly enter the shaping process, while the over-sieve tea undergoes a second shaping at 150℃ for 20 minutes, with a tea moisture content of 12%, resulting in shaped leaves.

[0053] The shaped blades are directly fed into a 6CM-80 type impregnation machine for impregnation without cooling, maintaining the blade temperature at 43℃ to obtain impregnated blades.

[0054] Set the steeping time to 0 min, 20 min, 30 min, and 40 min for processing;

[0055] Without cooling, the leaves were shaped using a 6CYR-85 press and kneading machine for 8 minutes to obtain shaped leaves;

[0056] The drying process is carried out in two stages. The first stage involves shaping the leaves without cooling them, using a 6CH-10 chain plate dryer for rapid initial drying at 115℃ for 8 minutes, until the moisture content of the tea leaves reaches 10%. The initially dried leaves are then rapidly re-dried using the same 6CH-10 chain plate dryer at 85℃ until the moisture content is controlled below 7%. This yields the dried leaves.

[0057] After the dried leaves are cooled and rehydrated for 2 hours, they are then dried using a 6CH-10 chain plate dryer at a temperature of 115℃ and a leaf thickness of 2.0cm until the tea leaves develop a sweet aroma, thus obtaining the finished tea product.

[0058] Experimental results show that black tea treated with aging has a significantly reduced bitterness and astringency, and the color of the tea liquor and the tea leaves is redder. However, the aroma concentration decreases after 30 minutes, and the optimal time is 30 minutes.

[0059] Table 2. Effects of aging time on the sensory quality of pearl-shaped Lichuan red.

[0060]

[0061] Note: Fresh leaves were harvested on July 1, 2023; the full score for each item in the table is 100, and the weighted score is calculated based on appearance (25%), liquor color (10%), aroma (25%), taste (30%), and leaf residue (10%); the data are the mean ± standard deviation of three replicates. Different uppercase letters in the same column indicate extremely significant differences at the p < 0.01 level, and lowercase letters indicate significant differences at the p < 0.05 level.

[0062] Example 4:

[0063] The impact of shaping on the quality of pearl-shaped black tea. This includes the following steps:

[0064] Comparative Example 3 follows the same process as Example 1, except that the shaping method is omitted in step (9). The other implementation steps are the same as in Example 1.

[0065] Experimental results show that, compared with unshaped tea leaves, shaped tea leaves are more tightly rolled and have a higher degree of uniformity.

[0066] Table 3. Effects of Shaping on Sensory Quality of Pearl-shaped Lichuan Red

[0067]

[0068] Note: Fresh leaves were harvested on May 1, 2023; the full score for each item in the table is 100, and the weighted score is calculated based on appearance (30%), liquor color (10%), aroma (25%), taste (25%), and leaf residue (10%); the data are the mean ± standard error of three replicates. Different uppercase letters in the same column indicate extremely significant differences at the p < 0.01 level, and lowercase letters indicate significant differences at the p < 0.05 level.

[0069] Finally, it should be noted that the above embodiments do not limit the present invention in any way. Those skilled in the art can make modifications and improvements based on the present invention. Therefore, any modifications or improvements made without departing from the spirit of the present invention are within the scope of protection claimed by the present invention.

Claims

1. A mechanized processing method for pearl-shaped Lichuan red apricots, comprising the steps of fresh leaf picking, withering, rolling, fermentation, drying, shaping, aging, setting, drying, and aroma enhancement, specifically including the following steps: (1) Variety selection: Choose any one of Echa No. 10, Lenghouhun, or Huahong No. 1; (2) Fresh leaf picking: The standard is one bud and two or three leaves. The leaves are picked by hand, without squeezing or damaging them. (3) Withering: Withering troughs or automatic withering machines can be used. The leaf thickness is 10cm-15cm, the withering time is 8h-12h, and the degree of withering is such that the moisture content of the buds and leaves is 55%-58% to obtain withered leaves. (4) Rolling: After the withered leaves have been rehydrated for 30-50 minutes, they are rolled using a 6CR-55 tea rolling machine for 100-120 minutes. After rolling, the leaves are broken up to obtain rolled leaves. (5) Fermentation: The rolled leaves are processed using a black tea fermentation machine. The fermentation temperature is around 35℃, the air humidity is above 90%, and the time is 4.5h-5.0h. The leaves are fermented until they turn yellow-red to obtain fermented leaves. (6) Harvesting: Fermented leaves are harvested using a fragrant tea drying machine at a temperature of 200-220℃ and a tea moisture content of 35%-39% to obtain harvested leaves; (7) Shaping: The leaves are dried using a pearl tea drying machine and shaped in two stages. First shaping: temperature 170℃~190℃, time 20min~25min, tea moisture content 20%~25%. Second shaping: the leaves shaped in the first stage are shaped using a round sieve machine with a sieve of 0.85cm~1.00cm to separate the tea from the sieve. The tea from the sieve goes directly into the shaping process, while the tea from the sieve undergoes a second shaping at a temperature of 150℃~170℃ for 20min~25min, with a tea moisture content of 12%~15%, to obtain the shaped leaves. (8) Methanol infusion: The shaped leaves are directly fed into the ethanol infusion machine without cooling, and the leaf temperature is maintained at 40-45℃ for 30 minutes to obtain ethanol-infused leaves; (9) Shaping: The leaves are not cooled before being shaped by a kneading machine for 5 to 10 minutes to obtain shaped leaves; (10) Drying: The drying is done in two stages; the first stage is for shaping the leaves without cooling. The leaves are quickly dried using a chain plate dryer or aroma enhancer at a temperature of 110-120℃ for 5-10 minutes until the moisture content of the tea leaves is 8-10%; the leaves are then quickly re-dried using a chain plate dryer or aroma enhancer at a temperature of 80-90℃ until the moisture content of the tea leaves is controlled below 7%, thus obtaining dried leaves. (11) Aroma Enhancement: After cooling the dried leaves, rehydrate them for 1-2 hours. Use a chain plate dryer or aroma enhancer to enhance the aroma at a temperature of 115-120℃ and a leaf thickness of 1-2.5cm. Dry until the tea has a sweet aroma, and then obtain the finished tea.

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