JP2006204183A - Stirring-type heating device and method for manufacturing tea - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stirring-type heating device manufacturing a large amount of green tea having both of advantages of pan-roasted tea and natural leaf tea in view of recent trend toward the pan-roasted tea: and to provide a method for manufacturing tea. <P>SOLUTION: The stirring-type heating device is provided with a tea leaf treatment device comprising: a fixed cylinder the lower part of which has a semi circular shape and the upper part of which is open; a rotary axis laterally bridged to the fixed cylinder; a stirring hand pivoted to the rotary axis; a heating means heating the lower part of the fixed cylinder from outside; a blasting means blasting air into the fixed cylinder; a temperature detecting means of the fixed cylinder; and a temperature controlling means making the temperature of the fixed cylinder to a desired one. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for frying tea leaves and a tea making method using the apparatus.

  The green tea production method involves steaming the raw leaves picked from the tea plantation against abundant saturated steam and steaming them, followed by the steps of crude koji, koji, middle koji, refined koji, and drying. There is a method in which the raw leaves are fried on a heated “kama”, and then the koji roasted tea is produced through each process of twisting, water-drying, tightening, and finishing. Sencha is a treatment that loses the activity of oxidase by applying a large amount of steam to fresh tea leaves, so it is characterized by maintaining the green color of fresh tea leaves, whereas roasted tea is made of heated iron plates, etc. Since it is fried above, it is characterized by the roasted flavor of tea. Conventionally, sencha has been mainly produced, but with the diversification of life, kettle roasted tea with a unique flavor has been reviewed.

Conventionally, as a device for roasting fresh tea leaves, there is a fixed cylinder whose lower part is a semi-cylindrical shape and whose upper part is opened, and the fixed cylinder is heated from below (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3). is there.
JP-A-57-181640 Japanese Utility Model Publication No. 62-80580 No. 1-337427

  In the conventional method of cooking the kettle, the green tea leaves themselves (water vapor evaporated from the fresh tea leaves) and the heat of the tea leaves in contact with the body heated to a high temperature are used to kill blue (deoxidizing oxidase). As the tea leaves with less moisture and thicker stems are more prone to blue killing, they tend to cause unevenness of blue killing and are difficult to operate. In addition, it takes a long time to kill blue, it is inefficient, and it is suitable for soft tea leaves like tea, but it is not suitable for hard leaves like Sanbancha or Akibacha was there.

  On the other hand, in the manufacturing method of sencha, Nibancha and Sanbancha, which are picked from June to August, have a summer tea odor and little umami components such as amino acids. It was dealt with by attaching strong incense). However, in order to increase the intensity of the incense, it is necessary to increase the temperature of the tea leaves and take a long time. As a result, the tea leaves of the products of Nibancha and Sanbancha, which originally had little chlorophyll, may be lost.

  Recently, the flavor of kettle roasted tea has been favored, and it is an object to provide an apparatus and method that can produce a large amount of green tea having the best of kettle roasted tea and sencha.

  The stirring-type heat treatment apparatus of the first means of the present invention comprises a fixed cylinder whose lower part is semicylindrical and whose upper part is opened, a rotating shaft that lies horizontally in the fixed cylinder, a stirring hand that is attached to the rotating shaft, It comprises heating means for heating the lower part of the fixed cylinder from the outside, blowing means into the fixed cylinder, temperature measuring means for the fixed cylinder, and temperature control means for setting the temperature of the fixed cylinder to a desired temperature. The stirring type heat treatment apparatus of the second means uses the air warmed by the heating means of the stirring type heat treatment apparatus of the first means for blowing.

  In the tea making method of the third means, the tea leaves after the steam heat treatment are heat-treated with the stirring type heat treatment apparatus described in the first means or the second means. In the tea making method of the fourth means, the tea leaves after the heat treatment of the third means are subjected to rough koji, twisting, and middle koji treatment and dried.

  The present invention can uniformly treat thick tea leaves with a small amount of moisture and developed fibers by steaming heat treatment using abundant saturated steam, and the steamed tea leaves are heated to a high temperature by a stirring type heat treatment device. Combines the characteristics of a traditional kettle roasted tea with the heated fixed barrel, the light blue color due to uniform steam-killing by steaming, and the good extractability through the rough koji process. Tea products can be manufactured, enabling mass processing.

  The apparatus of the present invention will be described with reference to FIGS. Reference numeral 1 denotes a stirring type heat treatment apparatus. In this embodiment, a continuous stirring type heat treatment apparatus will be described. Reference numeral 2 denotes a fixed cylinder having a semi-cylindrical lower portion and an open upper portion (upper opening 3). Reference numeral 4 denotes a rotating shaft that lies horizontally in the fixed cylinder, and a plurality of stirring hands 5 are attached to the shaft. The agitator 5 is attached in a spiral shape so as to transfer tea leaves from the tea leaf inlet 6 to the tea leaf outlet 7. Reference numeral 8 denotes a heating chamber provided outside the fixed cylinder 2 and includes a gas burner 9 which constitutes a heating means. Reference numeral 10 denotes a blower chamber provided on the back surface of the fixed drum 2, which is provided with a blower fan 12 and constitutes a means for blowing hot air to the fixed drum 2. The heating chamber 8 and the air blowing chamber 10 are connected by a duct 14, and the air that has accumulated in the heating chamber 8 is guided to the air blowing chamber 10. The blower fan 12 blows air and outside air guided from the duct 14 into the blower chamber 10. Reference numeral 16 denotes a damper that adjusts the amount of air introduced from the heating chamber 8. A temperature sensor 21 measures the temperature of the fixed cylinder 2. Reference numeral 22 denotes temperature control means for controlling the combustion of the gas burner 9 so that the temperature measured by the temperature sensor 21 becomes a predetermined temperature.

  First, the gas burner 9 in the heating chamber 8 is ignited to heat the fixed cylinder 2, and the rotating shaft 4 is driven by the driving means 17. After the temperature of the fixing cylinder 2 reaches a predetermined temperature (about 200 degrees in this embodiment) by the temperature control means 22, the tea leaves are fed from the charging port 6 by the charging conveyor 26. The tea leaves are stirred by a plurality of stirring hands 5 while being in contact with the heated fixed barrel 2 to dissipate the moisture of the tea leaves themselves and add a roasted incense. If there is a lot of water in the tea leaves, the temperature of the tea leaves will not rise easily due to the latent heat of vaporization, so not only the roasting incense will be given, but also the water will not be released by agitation and the moisture will be kept between the tea leaves, causing stuffiness and quality. Cause it to drop. Therefore, since it becomes necessary to forcibly drain moisture, the air is blown by the blower fan 12 in the blower chamber 10. At this time, the temperature of the blast is adjusted by changing the opening degree of the damper 16 of the duct 14. When the damper 16 is closed, the blower fan 12 sucks the outside air and blows the outside air into the fixed barrel 2. When the damper 16 is opened, the blower fan 12 sucks the air in the heating chamber 8 and blows warm air to the fixed cylinder 2. In this way, tea leaves with no stuffiness and no summer tea odor are produced. When the water content of the tea leaves is low, if the blower fan 12 is stopped, no air is blown into the fixed drum 2.

  In this embodiment, since the stirring hand 5 is attached in a spiral shape toward the tea leaf discharge port 7 in a continuous manner, the tea leaf automatically moves to the tea leaf discharge port 7. The tea leaves discharged from the tea leaf discharge port 7 are conveyed to the next process by the discharge conveyor 27. A part of the lower portion of the fixed drum 2 is a tea leaf outlet 19. When all the tea leaves in the fixed drum 2 are taken out, the tea leaf outlet 19 is opened and the tea leaves are taken out on the take-out conveyor 28.

  FIG. 4 shows a flow of a manufacturing method using the above apparatus. First, the raw tea leaves are steamed before being processed by the above apparatus. The tea leaves after the steaming heat treatment are put into the above apparatus. The tea leaves that have been heat-treated in the above apparatus are subjected to rough koji, twisting, and middle koji processing. Usually, the steaming process is continuous and the rough koji treatment is batch type. Therefore, when the heat treatment is continuous as in this embodiment, a measuring instrument is provided before the rough kneading process.

  The apparatus of the present invention may be a batch type. In the case of the batch type, a measuring instrument for measuring the batch amount is provided in front of the stirring type heat treatment apparatus. Further, in the case of the batch type, the stirring hand 5 is not attached in a spiral shape, the tea leaf outlet 7 is unnecessary, and all the tea leaves are taken out from the tea leaf outlet 19 at the lower part of the fixed barrel 2.

  The apparatus of the present embodiment will be described with reference to FIGS. The present embodiment is different from the above embodiment in hot air blowing means (other parts are the same as those in the above embodiment), and the hot air blowing means will be described. Reference numeral 32 denotes an exhaust duct that exhausts the air heated in the heating chamber 8 provided outside the fixed barrel 2 to the outside of the heating chamber 8. Reference numeral 31 denotes an intake duct, and the intake duct 31 covers the exhaust duct 32. The air in the intake duct 31 is warmed by the heat accumulated in the heating chamber 8 passing through the exhaust duct 32. The warmed air is guided to the blower chamber 10 and is blown into the fixed drum 2 by the blower fan 12.

The perspective view of the apparatus of this invention. The side sectional view of the device of the present invention. The rear sectional view of the device of the present invention. The figure which showed the flow of the tea manufacturing method of this invention. FIG. 3 is a rear cross-sectional view of the first embodiment. FIG. 3 is a cross-sectional view taken along the line AA of Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stirring type heat treatment apparatus 2 Fixed cylinder 3 Upper opening 4 Rotating shaft 5 Stirrer 6 Tea leaf inlet 7 Tea leaf outlet 8 Heating chamber 9 Gas burner 10 Blower chamber 11 Motor 12 Blower fan 13 Hot air inlet 14 Duct 16 Damper 17 Drive part 18 Frame 19 Tea leaf outlet 21 Temperature sensor 22 Temperature control means 26 Input conveyor 27 Discharge conveyor 28 Extraction conveyor 31 Intake duct 32 Exhaust duct

Claims (4)

  A fixed cylinder whose lower part is semi-cylindrical and whose upper part is open, a rotating shaft that lies horizontally in the fixed cylinder, an agitator attached to the rotating shaft, a heating means that heats the lower part of the fixed cylinder from the outside, and a fixed cylinder An agitating type heat treatment apparatus comprising: an air blowing means; a temperature measuring means for a fixed cylinder; and a temperature control means for setting the temperature of the fixed cylinder to a desired temperature.   The stirring type heat treatment apparatus according to claim 1, wherein the air warmed by the heating means is used for blowing air.   A tea-making method, wherein the tea leaves after steaming are heat-treated with the stirring-type heat treatment apparatus according to claim 1 or 2.   4. The tea making method according to claim 3, wherein the tea leaves after the heat treatment are subjected to rough koji, twisting, and middle koji treatment and dried.

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