Tea leaf manufacturing method

Abstract

To provide a production method of tea leaves capable of eluting a caffeine component in the tea leaves without increasing production processes.SOLUTION: A production method of tea leaves for eluting a caffeine component in the tea leaves to reduce caffein, includes: a process of making the tea leaves wet; a steaming process S1 of steaming the tea leaves while stirring the tea leaves by a rotary action of a barrel part capable of housing the tea leaves in a steamer and stirring means configured to stir the tea leaves housed in the barrel part; a cooling process S2 of cooling the tea leaves steamed at the steaming process S1; and a dehydration process S4 of dehydrating the tea leaves cooled at the cooling process S2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing tea leaves in which the caffeine content in the tea leaves is reduced by eluting the caffeine component from the tea leaves. [Background technology]

[0002] When black tea leaves or tea leaves harvested in the summer (summer tea) are processed using the same method as green tea, the resulting product may have a strong bitter and astringent taste and a dull color. This is thought to be because black tea leaves and summer teas contain large amounts of bitter and astringent components such as caffeine and catechins, and have relatively thick mesophyll. To elute bitter and astringent components such as caffeine, a technique such as that disclosed in Patent Document 1 can be used. According to this conventional technique, the caffeine content of the tea leaves can be adjusted by including a blanching step. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-110797 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional technology, although the blanching process allows the bitter and astringent components to be dissolved and the amount of caffeine to be adjusted, a separate dedicated process for blanching is required, which increases the number of manufacturing processes and results in significant equipment installation costs.

[0005] The present invention has been made in view of the above circumstances, and aims to provide a method for producing tea leaves that can efficiently extract caffeine components from tea leaves while reducing equipment installation costs. [Means for solving the problem]

[0006] The invention described in claim 1 is a method for producing tea leaves that reduces the caffeine content by eluting the caffeine components in the tea leaves, and is characterized by comprising the steps of: wetting the tea leaves with water; steaming the tea leaves while stirring them by rotating a body of a steamer that can accommodate the tea leaves and a stirring means that stirs the tea leaves accommodated in the body; cooling the tea leaves steamed in the steaming step; and dehydrating the tea leaves cooled in the cooling step.

[0007] The invention described in claim 2 is the method for producing tea leaves described in claim 1, is carried out between the cooling step and the dehydration step, The method is characterized in that it includes a hammering step in which hammering pressure is applied to the tea leaves cooled in the cooling step.

[0008] The invention described in claim 3 is characterized in that, in the method for producing tea leaves described in claim 1, the dehydration process is carried out by a dehydrator that pressurizes and dehydrates the tea leaves while they are being transported by a transport means.

[0009] The invention described in claim 4 is characterized in that, in the method for producing tea leaves described in claim 3, the dehydrator has a roller that can apply a predetermined load to the tea leaves on the conveying means to apply pressure, and dehydrates the tea leaves by arbitrarily adjusting the load applied to the tea leaves or the speed ratio of the roller and the conveying means. [Effects of the Invention]

[0010] According to the present invention, the caffeine component in tea leaves can be efficiently extracted while reducing the cost of installing equipment. [Brief explanation of the drawings]

[0011] [Figure 1] A flowchart showing a method for producing tea leaves according to an embodiment of the present invention. [Figure 2] FIG. 1 is a block diagram showing a tea leaf manufacturing system according to an embodiment of the present invention. [Figure 3] A plan view showing the steamer applied to the tea leaf manufacturing system. [Figure 4] Side view of the steam locomotive [Figure 5]A vertical cross-sectional view showing the internal structure of the steam engine [Figure 6] A plan view showing a pressing machine applied to the tea leaf manufacturing system. [Figure 7] FIG. 10 is a vertical cross-sectional view showing the internal configuration of the punching machine. [Figure 8] A plan view showing a dehydrator applied to the tea leaf manufacturing system. [Figure 9] FIG. 10 is a side view showing the dehydrator; [Figure 10] Schematic diagram for explaining the dewatering action by the mesh belt and rollers in the dehydrator. [Figure 11] FIG. 10 is a side view showing the dehydrator installed between the steaming process and the drying process. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The method for producing tea leaves according to this embodiment is a method capable of eluting components in tea leaves such as caffeine, and as shown in FIG. 1, includes a steaming step S1 in which the tea leaves are steamed to inactivate enzymes, a cooling step S2 in which the tea leaves steamed in the steaming step S1 are cooled, a beating step S3 in which the tea leaves are beaten to soften them, a dehydration step S4 in which the tea leaves are pressed and dehydrated before the drying step S5, and a drying step S5 in which the tea leaves are dried.

[0013] As shown in Figure 2, the tea leaf manufacturing system of this embodiment includes a steamer 1 that performs the steaming process S1, a cooler 2 that performs the cooling process S2, a presser 3 that performs the pressing process S3, a dehydrator 4 that performs the dehydration process S4, and a dryer 5 that performs the drying process S5.

[0014] The steamer 1 according to this embodiment is capable of inactivating enzymes by mixing fresh leaves fed from a leaf feeder with steam while stirring them, and as shown in Figures 3 to 5, is configured to include a feeder section 6, a trunk section 7, and blade-shaped members 8 (stirring means). A fixed frame F1 is fixed to the floor, and a movable frame F2 is swingably connected to the fixed frame F1, on which the feeder section 6 and trunk section 7 are mounted. The feeder section 6 and trunk section 7 can be tilted at a predetermined angle by swinging the movable frame F1 relative to the fixed frame F1.

[0015] The input section 6 is fixed to the movable frame F2 and is formed with an input port 6a through which tea leaves can be input and a supply port 6b connected to the steam supply means K and capable of supplying steam to the internal storage space. The body 7 is connected to one end of the input section 6 and is made of a tubular member that can accommodate tea leaves input through the input port 6a, and is rotatable around its axis on the movable frame F2. The body 7 in this embodiment is also made of a mesh-like member that allows steam to pass through. The blade-like members 8 (agitating means) are used to stir the tea leaves in the body 7 by stirring them up, and are formed in plurality on a shaft member L1 that extends axially inside the input section 6 and body 7.

[0016] The steam supplied from the steam supply means K flows through the pair of pipes H2 via pipe H1 and is sprayed into the inside of the input section 6 from the supply port 6b. Then, by rotating the trunk section 7 relative to the input section 6 and rotating the shaft member L1 to rotate the vane-shaped members 8, and then adding tea leaves from the input port 6a, the added tea leaves are agitated by the rotation of the trunk section 7 and the vane-shaped members 8, and are steamed by the steam supplied from the supply port 6b. In this way, the tea leaves steamed with steam pass through the inside of the rotating trunk section 7 while being agitated by the vane-shaped members 8, and are discharged from the discharge port N.

[0017] In this embodiment, the tea leaves introduced into the body 7 through the introduction port 6a are wet with water. For example, a soaking step of wetting the tea leaves with water can be performed before the steaming step S1 is performed. The soaking step can be a step of using a washer to wash the tea leaves introduced into the introduction port 6a with water (cold water or hot water) so that the tea leaves are wetted with water while being washed, or a step of spraying or spraying shower water onto the tea leaves to thoroughly wet the tea leaves with water. Alternatively, the tea leaves can be soaked in a water tank containing cold or hot water, and then the wet tea leaves can be introduced into the introduction port 6a.

[0018] In this way, the tea leaves are wet with water before being placed in the trunk 7, and so any components in the tea leaves, such as caffeine, can be eluted in the process of being steamed while being stirred by the rotation of the trunk 7 and the blade-like members 8. In other words, according to the steamer 1 of this embodiment, the tea leaves in a wet state can be steamed in the process of passing through the trunk 7, thereby deactivating enzymes and eluting components in the tea leaves, such as caffeine.

[0019] Furthermore, in the steamer 1 according to this embodiment, the tea leaves are wet with water before being placed into the barrel 7, but water (hot water) may be supplied into the barrel 7 to wet the tea leaves. In this case, it is preferable to provide a supply means such as a shower for supplying water into the barrel 7, so that the tea leaves are steamed and the enzymes are deactivated while they are wet with water as they pass through the barrel 7, allowing components in the tea leaves such as caffeine to be eluted. Note that water may also be poured onto the outside of the barrel 7 to wet the tea leaves.

[0020] In particular, it is preferable that the water supplied to the body 7 is steamed at 10 to 100°C (especially preferably 85°C or higher) for 20 to 180 seconds (especially preferably 60 seconds or longer). By using such conditions, the components in the tea leaves, such as caffeine, can be effectively eluted, and both the steaming action of the tea leaves and the elution action of the components can be effectively achieved.

[0021] The cooler 2 is designed to spray or squirt cold water onto the tea leaves discharged from the outlet N of the steamer 1, thereby cooling the tea leaves while washing away components such as caffeine that have been dissolved by the steamer 1. The cooler 2 may be designed to only cool the tea leaves by blowing cold air onto the tea leaves instead of spraying or squirting cold water, or may be designed to transport the tea leaves from the steamer 1 to the pressing machine 3 while blowing cold water or cold air onto the tea leaves.

[0022] The pressing machine 3 applies pressure to the tea leaves to soften them, causing the core water to rise, improving the kneading process in the drying step S5, and improving drying efficiency. As shown in Figures 6 and 7, it is composed of an input section 9, a body section 10, blade-shaped members 11, and a screw-shaped member 12. A fixed frame F3 is fixed to the floor, and a movable frame F4 is connected to the fixed frame F3 so that the input section 9 and body section 10 are disposed on the movable frame F4. The input section 9 and body section 10 can be tilted at a predetermined angle by swinging the movable frame F4 relative to the fixed frame F3.

[0023] The input section 9 is fixed to the movable frame F4 and has an input port 9a through which tea leaves can be input. The body section 10 is connected to one end of the input section 9 and is made of a cylindrical member that can accommodate tea leaves input through the input port 9a, and is rotatable around an axis on the movable frame F4. Furthermore, the body section 10 according to this embodiment has a plurality of ducts (uneven shapes) formed on its inner circumferential surface.

[0024] The blade-like members 11 are used to stir and stir the tea leaves inside the body 10, and are formed in plurality on an axial member L2 that extends axially inside the input section 9 and the body 10. A screw-like member 12 is formed on the input section 9 side of the axial member L2, so that tea leaves input from the input opening 9a can be transported by the screw-like member 12 toward the inside of the body 10.

[0025] Then, by rotating the body 10 relative to the input section 9 and driving the shaft member L2 to rotate, the blade-shaped member 8 and the screw-shaped member 12 are rotated, and then tea leaves are input through the input port 9a, whereby the input tea leaves are stirred by the rotation of the body 10 and the blade-shaped member 11, and the tea leaves are struck and compressed. In other words, the blade-shaped member 11 is configured to strike the tea leaves and compress them, and the tea leaves (steamed leaves) in the input section 9 are transported into the body 10 by the screw-shaped member 12, and are struck and stirred by the blade-shaped member 11.

[0026] The dehydrator 4 pressurizes and dehydrates tea leaves that have been wetted with water and whose enzymes have been deactivated by the steamer 1, and is capable of dehydrating the tea leaves by pressurizing them before the drying step S5 is carried out. Specifically, the dehydrator 4 according to this embodiment is capable of dehydrating the tea leaves in the process of transporting them to the drying step S5, and as shown in Figures 8 and 9, it comprises a mesh belt 13 (transport means) that transports the tea leaves whose enzymes have been deactivated by the steamer 1 to the dryer 5, and rollers 14 (pressure means) that pressurize and dehydrate the tea leaves as they are transported by the mesh belt 13.

[0027] The mesh belt 13 is made of a mesh-like (mesh-like) carrier suspended endlessly between a drive pulley P1 and a driven pulley P2, and is disposed on the main frame F5. By driving the drive pulley P1, the mesh belt 13 can be moved between the drive pulley P1 and the driven pulley P2, so that by placing tea leaves on the mesh belt 13 from the input section 16, the tea leaves can be transported to the output section 17.

[0028] A plurality of sub-frames F6 are connected and arranged above the main frame F5 (two locations in this embodiment), and each sub-frame F6 is equipped with a roller 14 as a pressure means, a motor M for driving the roller 14 to rotate, and a weight 15. The roller 14 is rotatable about an axis L3 formed on the sub-frame F6, and is configured to rotate in direction b about axis L3 when the mesh belt 13 moves in direction a, as shown in Fig. 10.

[0029] The sub-frame F6 is also able to swing relative to the main frame F5 around an axis L4, and by arbitrarily adjusting the swing angle of the sub-frame F6, it is possible to adjust the distance t between the roller 14 and the conveying surface of the mesh belt 13. Furthermore, the weight of the weight 15 presses the roller 14, which then presses the tea leaves on the mesh belt 13 via the roller 14, thereby dehydrating them. A receiving plate 18 is attached below the main frame F5 to receive water produced when the tea leaves are dehydrated.

[0030] Therefore, when tea leaves are conveyed by mesh belt 13, a predetermined load can be applied to the tea leaves during conveyance by driving motor M to rotate rollers 14, and this pressure can cause the moisture in the tea leaves to be released to the outside, thereby dehydrating them. Also, by optionally adjusting the distance t between rollers 14 and the conveyance surface of mesh belt 13, or by optionally setting the weight and attachment position of weight 15, the load applied to the tea leaves can be optionally adjusted.

[0031] In addition, the load applied to the tea leaves can be adjusted as desired by arbitrarily changing the ratio between the moving speed of the mesh belt 13 and the rotation speed of the rollers 14. In this way, by arbitrarily adjusting the load applied to the tea leaves or the speed ratio between the rollers 14 and the mesh belt 13 (conveying means) during dehydration, the degree of crushing of the tea leaves and the amount of components eluted can be adjusted, and tea leaves containing the desired components can be obtained. Note that the rotating surface of the rollers 14 may be knurled or otherwise processed to increase the degree of crushing of the tea leaves.

[0032] 11, legs H can be attached to the lower part of the main frame F5 and tilted at a predetermined angle, and a conveying device A for conveying tea leaves that have been through the steaming process S1 and the cooling process S2 can be arranged on the side of the carrying-in section 16, and a conveying device B for conveying tea leaves to the drying process S5 can be arranged on the side of the carrying-out section 17. As a result, the tea leaves conveyed by conveying device A can be dehydrated by the dehydrator 4 in the process of being conveyed towards conveying device B, allowing components such as caffeine to be eluted.

[0033] The dryer 5 used in the drying step S5 is made up of various drying devices used in green tea production lines such as regular sencha lines, tencha lines, CTC lines, minced tea lines, etc. The drying step S5 is not limited as long as it is green tea drying equipment.

[0034] According to this embodiment, the steaming step S1 is intended to dissolve the components in the tea leaves while steaming the tea leaves that are wet with water, and the steamer 1 is made of a cylindrical member that can accommodate tea leaves that have been added through the inlet 6a, and is equipped with a body 7 that can rotate around its axis, and blade-like members 8 (agitation means) that stir and stir the tea leaves in the body 7, and the body 7 dissolves the components in the tea leaves while steaming the tea leaves that are wet with water, so that any component in the tea leaves, such as caffeine, can be dissolved without increasing the number of manufacturing steps.

[0035] Furthermore, a soaking step in which the tea leaves are wetted with water can be carried out before the steaming step S1 is carried out, in which case the steamer 1 wets the tea leaves before they are placed in the trunk 7, so the tea leaves can be sufficiently wetted with water and the surfaces of the tea leaves can be washed before the steaming step S1 or before they are placed in the steamer 1. Furthermore, the tea leaves can be wetted with water during the steaming step, in which case the steamer 1 supplies water (hot water) into the trunk 7 to wet the tea leaves, so that any components in the tea leaves can be eluted by wetting the tea leaves with water during the steaming step S1.

[0036] Furthermore, before the drying step S5 is carried out, a dehydration step S4 is carried out in which the tea leaves are pressurized and dehydrated, and a dehydrator 4 is provided which pressurizes and dehydrates tea leaves that have been wetted with water and whose enzymes have been deactivated by the steamer 1, so that any components in the tea leaves can be more reliably and sufficiently eluted by dehydration, and the tea leaves can be dried more quickly in the drying step S5 or the dryer 5. However, the dehydration step S4 can squeeze out water while eluting components such as caffeine, so that adjustment of the contained components and efficient drying in the drying step S5 can be carried out at the same time.

[0037] In particular, in the dehydration step S4 of this embodiment, dehydration is performed in the process of transporting the tea leaves to the drying step S5, and the dehydrator 4 is equipped with a mesh belt 13 (conveying means) that transports the tea leaves, whose enzymes have been deactivated in the steamer 1, to the dryer 5, and rollers 14 (pressurizing means) that pressurize and dehydrate the tea leaves as they are transported by the mesh belt 13 (conveying means).Therefore, the tea leaves can be dehydrated while being transported, making tea leaf production more efficient.

[0038] Furthermore, the pressure means according to this embodiment is comprised of rollers 14 that can apply a predetermined load to the tea leaves on mesh rollers 13 (conveying means) to apply pressure, and the load applied to the tea leaves can be adjusted as desired, so that the amount of components eluted can be adjusted as desired depending on the product. Note that, although the purpose of this embodiment is to elute caffeine to reduce the caffeine content, it may also be intended to elute other components such as catechins.

[0039] Although the present embodiment has been described above, the present invention is not limited to this. For example, instead of the dehydrator 4 used in the dehydration step S4, a centrifugal dehydrator that uses centrifugal force for dehydration may be used, or two rotating rollers may be arranged at a predetermined distance apart and the tea leaves may be sent into the space between them for dehydration. Also, in this embodiment, the dehydration step S4 is performed after the beating step S3, but the beating step S3 may not be performed. The variety of tea leaves is not limited. [Industrial Applicability]

[0040] As long as the method for producing tea leaves includes the steps of wetting the tea leaves in water, steaming, cooling, and dehydrating, it can be applied to tea leaves with different external shapes or with added functions. [Explanation of symbols]

[0041] 1 Steam engine 2 Cooler 3. Pressing machine 4 Dehydrator 5 Dryer 6 Input section 6a Inlet 6b Supply port 7. Torso 8. Blade-shaped member (agitating means) 9 Input section 9a Inlet 10 Torso 11. Wing-shaped member 12 Screw-shaped member 13 Mesh belt (conveying means) 14 Roller (pressure means) 15 weight 16 Input section 17 Discharge section 18 Receiving plate

Claims

1. A method for producing tea leaves in which caffeine components in tea leaves are dissolved to reduce caffeine, The process of wetting the tea leaves with water, a steaming step in which the tea leaves are steamed while being stirred by rotating a body portion of the steamer capable of accommodating the tea leaves and a stirring means for stirring the tea leaves accommodated in the body portion; a cooling step of cooling the tea leaves steamed in the steaming step; a dehydration step of dehydrating the tea leaves cooled in the cooling step; A method for producing tea leaves, comprising:

2. A method for producing tea leaves as described in claim 1, characterized in that it includes a pressing step carried out between the cooling step and the dehydration step, in which pressure is applied to the tea leaves cooled in the cooling step.

3. 2. The method for producing tea leaves according to claim 1, wherein the dehydration step is carried out by a dehydrator that pressurizes and dehydrates the tea leaves while they are being transported by a transporting means.

4. The method for producing tea leaves as described in claim 3, characterized in that the dehydrator has a roller that can apply a predetermined load to the tea leaves on the conveying means to apply pressure, and dehydrates the tea leaves by arbitrarily adjusting the load applied to the tea leaves or the speed ratio of the roller and the conveying means.

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