JPH06165639A - Production of green tea using airborne dryer - Google Patents

Abstract

PURPOSE:To obtain green tea in a powdery or granular state suitable for tea bag by steaming raw leaves of tea, grinding or crushing under pressure, loosening pasty steamed stems and leaves, drying by an airborne dryer and drying under heating. CONSTITUTION:Raw leaves of tea are steamed with steam at 95-105 deg.C for tens seconds, ground or crushed under pressure by a grinder 1, made into a proper particle size by a loosening machine 4 and dried by an airborne dryer 2 in such a way that granules are at least hardly stuck mutually. The granules can be uniformly dried by a hot-air dryer 3 to a given drying degree.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a green tea in which steamed tea leaves which have been crushed or crushed into a paste form are heated and dried before being dried by air flow to lose the adhesiveness between particles. It relates to the manufacturing method of.

[0002]

2. Description of the Related Art Green tea is prepared by first contacting raw tea leaves picked in a tea garden with steam in a tea leaf steamer for several tens of seconds to stop fermentation and then steaming, rubbing, kneading, middle rubbed, refined, It is made by adding treatments such as drying to tens of minutes to make rough tea, and then adding firing and other finishing treatments to it. This green tea is the most abundant in Japan and is consumed daily. In particular, recently, in addition to tannin and caffeine, the inclusion of various medicinal components in addition to vitamins such as vitamin C has attracted attention not only as a favorite beverage but also as a health beverage.

[0003]

Among the conventional manufacturing processes of green tea described above, in the processing steps from the rough kneading step to the fine kneading step, the steamed tea leaves are kneaded while being heated to gradually reduce the water content of the tea leaves. While doing this, it is twisted to finish it into a rod shape. In this treatment method, since it takes a long time to twist the tea leaves, the workability is poor, and the treatment must be performed at a relatively low temperature in order to match the degree of decrease in water content with the time, It was not possible to obtain a product green tea with a strong umami or flavor. Moreover, this green tea is suitable for brewing using a teapot because it is stick-shaped, but it is difficult to fill it in a small bag and the elution property of the drinkable component is low, so it is used as a tea bag. I can't. As a measure for solving such a problem, the present inventor has found a method for obtaining green tea by making steamed tea leaves into a paste and then heating and drying the paste, and has already applied for a patent. This method does not require the time to twist the tea leaves to form a stick shape, and can heat and dry only the conditions to enhance the umami and flavor of the green tea product, which improves workability. However, there is an advantage that a product with good quality and high elution property can be obtained. However, since the steam-dried tea leaves are heated and dried by a multi-stage conveyor hot-air dryer, paste-like steamed tea leaves stick to each other in the dryer to form lumps, which significantly reduces the drying efficiency. Therefore, not only the processing efficiency becomes low, but the steamed tea leaves in a lump form have different heating and drying conditions between the surface layer part and the inner part, which causes unevenness in the product green tea, resulting in low quality. There was a problem called. It is an object of the present invention to provide a method for producing green tea by heating a paste-like steamed tea leaf with a hot air dryer and drying it.

[0004]

Means for Solving the Problems The present invention is to prepare raw steamed tea leaves picked from a tea garden by steaming at 95 to 105 ° C. for several tens of seconds to prepare steamed tea leaves, or steamed tea leaves for 20 to 30 minutes. Or, after crushing with a roll to make the material steamed tea leaves, crush this using a crusher or a crushing roll until it looks like a paste, then at least this steamed tea leaves using an airflow dryer, The above-mentioned object is achieved by a method in which air-flow drying is carried out until the surface completely or almost loses tackiness, and this is further heated at a predetermined temperature to a predetermined dryness and dried. Install a crusher or a crusher under the crushing roll, connect an air dryer with a crusher installed in the middle of the air duct, and connect it to the crusher or crushing roll until it looks like a paste. The crushed steamed tea leaves are first loosened by a loosening machine to a size that can be sent to a crusher, and this steamed tea leaf has a high efficiency of air flow drying, and moreover it is dried by a conveyor hot air dryer. It can be an example in which the material is crushed to a suitable particle size. In addition, by installing a cyclone type collector or a fluidized bed dryer near the end of the air duct, the air flow dryer adjusts the residence time of the steamed tea leaf particles in the air flow until the air flow becomes appropriate. An example of drying may be used.

[0095]

According to the present invention, the steamed tea leaves which have been steam-heated and made into a paste form are subjected to airflow drying while being crushed using an airflow dryer. , Becomes a powder and granule suitable for drying.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of the present invention will be specifically described below with reference to the illustrated embodiments. In this embodiment, the green tea manufacturing apparatus is
It consists of a kneading machine 1, an air flow dryer 2, and a multi-stage conveyor hot-air dryer 3. The kneading machine 1 is connected to a constant amount supply conveyor, and the material steamed tea leaves steamed by a tea leaf steamer (not shown). In addition to being quantitatively charged to this, a loosening machine 4 is provided below the kneading machine 1 to transfer the steamed tea leaves made into a paste by the kneading machine 1 by air flow. Airflow dryer 2 by loosening to the extent possible
It is supposed to be sent to. The airflow dryer 2 is provided between the disentangling machine 4 and the inlet 31 of the hot air dryer 3, the hot air generator 21 is attached to the start end thereof, and hot air is blown into the air feeding duct 22. The surface of the steamed tea leaf particles is dried until the surface of the particles is completely or almost completely lost. Further, a rotary blade type crusher 23 is installed in the middle of the air feeding duct 22 so that the steamed tea leaves fed in the duct 22 have a high efficiency of air flow drying, and further, a particle size suitable for drying with a hot air dryer. It is designed to be crushed into pieces. The hot-air dryer 3 heats the powdery granular steamed tea leaves preliminarily dried by the airflow dryer 2 to a predetermined degree of dryness at a predetermined temperature and dries it. Conveyors or vibratory conveyors 33, 34, 35, 36 are provided. Then, a steaming tea leaf input port 31 is formed on the upper surface of the drying chamber 32, and when the steaming tea leaf is loaded into the drying chamber 32 from this, the steaming tea leaf first comes to the start end of the vibration conveyor 33 at the uppermost stage. The product is placed and transferred, and then transferred to the lower vibrating conveyor in order, and finally the product green tea is discharged from the take-out port 37 and taken out. Also, the drying room
A hot air generator 5 is connected to 32, and hot air of about 110 to 200 is sent to the drying chamber 32, and a far infrared heater 6 is attached to the upper part of each vibrating conveyor to move on the vibrating conveyor. The steamed tea leaves are heated to a predetermined temperature and dried.

When producing green tea, fresh green tea leaves carried from the tea garden are steamed with steam at 95 to 105 ° C. for several tens of seconds to obtain steamed tea leaves. If necessary, the steamed tea leaves are further beaten for 20 to 30 minutes or crushed with a roll to soften them, and then the kneading machine 1 is used by a constant quantity supply conveyor.
Quantitatively, the leaf veins and tea stems are crushed, some of the mesophyll cells are broken, the cell membrane is crushed, and it is kneaded until it looks like a paste and dropped into the loosening machine 4, where The air duct 22 of the airflow dryer 2 loosens the air to a size that allows it to be sent to the airflow dryer 2, and the hot air generator 21 sends hot air of about 110 to 200 ° C to this to crush it. Aired to machine 23. And crusher
In 23, the efficiency of air flow drying of this granular steamed tea leaf is high,
Moreover, it is crushed to a size suitable for drying with a hot air dryer,
At least the surface of the particles is dried to such an extent that the particles do not stick to each other, and is brought into a so-called semi-dry state.
110 to 200 are fed from the hot air generator 5 into the drying chamber 32 while the powdered granular steamed tea leaves are sequentially transferred from the uppermost vibrating conveyor 33 to the lower vibrating conveyor. Hot air of about ℃ is applied to this, and it is heated by irradiating with far infrared rays and dried to a predetermined dryness.

[0008]

INDUSTRIAL APPLICABILITY As described in detail above, according to the present invention, raw tea leaves picked from a tea field are steamed with steam at 95 to 105 ° C. for several tens of seconds to be steamed tea leaves, which are crushed or crushed into a paste. Prior to heating and drying the dried product with a hot air dryer, it was crushed with a loosening machine to an appropriate particle size and air-flow dried until it became difficult for the particles to stick to each other. This can be heated and dried in the same manner as described above. Therefore, high quality green tea can be efficiently produced even though the material steamed tea leaves are in a paste form.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a tea making device used in a method of the present invention.

[Explanation of symbols]

 1 kneading machine 2 air flow dryer 3 hot air dryer 4 disentangling machine 5 hot air generator 6 far-infrared heater 21 hot air generator 22 air duct 23 crusher 31 input 32 drying chamber 33 vibration conveyor 34 vibration conveyor 35 vibration conveyor 36 vibration Conveyor 37 outlet

Claims (2)

[Claims] 1. Raw tea leaves picked from a tea garden are steamed with steam at 95 to 105 ° C. for several tens of seconds to make steamed tea leaves, or steamed tea leaves are beaten for 20 to 30 minutes or crushed by rolls. Material steamed tea leaves, then crush or crush until apparently paste-like, then loosen the paste-like steamed tea leaves to an appropriate particle size, and at least until the particles do not easily stick together A method for producing green tea using an airflow dryer, which comprises performing airflow drying using a dryer, followed by heating to a predetermined dryness and drying. 2. A loosening machine is provided below a device for crushing or crushing steamed tea leaves, and a crusher is attached to the airflow dryer in the middle of an air feeding duct to form a paste with the crushing device or the crushing device. The steamed tea leaves are first loosened by a loosening machine to the extent that they can be sent to a crusher, and the steamed tea leaves have a high efficiency of air flow drying by the crusher and are suitable for drying with a multi-stage conveyor hot air dryer. The method for producing green tea using the airflow dryer according to claim 1, wherein the green tea is crushed into pieces.