JPH01257455A - Device for roasting coffee bean - Google Patents

Abstract

PURPOSE:To obtain a product having good taste, aroma, etc., in extraction, by burying coil-shaped Nichrome wire into short conduit-shaped ceramic ware and providing a heater forming irregular stripes for uniforming thickness of ceramic ware in the front of the Nichrome wire and stirring means. CONSTITUTION:A heater attaching on the inside circumference face of furnace is formed into a heater having irregular stripes 5 for uniforming thickness of ceramic ware in front of Nichrome wire 2 by burying coil-shaped Nichrome wire 2 into ceramic ware 1 in zigzags and coffee bean stirred in a rotation drum by stirring means is irradiated with infrared ray having 3-10mu wavelength.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coffee bean roasting apparatus using an infrared heater as a heat source.

[Conventional technology and its problems]

Methods for roasting coffee beans are broadly divided into gas direct-fire methods and hot-air methods, but since gas direct-fire methods expose coffee beans directly to a heat source, only the surface of the beans is likely to burn, and the roasting temperature It has the disadvantage that it is difficult to control and tends to cause uneven baking. In addition, although the hot air method can roast coffee beans evenly compared to the gas direct fire method, it requires a large amount of hot air and a relatively long time, which increases thermal energy costs and takes time to roast. Therefore, it has the disadvantage of poor productivity in mass production.

In addition, in either method, heat does not penetrate sufficiently into the coffee beans, so it is generally difficult to obtain the high-quality aroma characteristic of coffee during extraction, although this affects the quality of the green coffee beans.

[Purpose of the invention]

Therefore, the present invention aims to select various heat sources for roasting,
This improvement allows heat to penetrate deep into the coffee beans, thereby significantly improving the taste, aroma, and shelf life of coffee when brewed.

[Means to achieve the purpose]

In order to achieve this purpose, the coffee bean roasting device of the present invention has coiled nichrome wires embedded uniformly in a zigzag pattern in a short gutter-shaped ceramic body with high thermal shock resistance. In this method, an uneven strip is formed to make the wall thickness of the ceramic body uniform in a series on the front side of a series of nichrome wires, and the coffee beans are irradiated with infrared rays with a wavelength of 3 to 10μ emitted from the front side of the ceramic body. This device is characterized by being equipped with a means for stirring coffee beans.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings. As shown in Figures 1 and 2, the heat source used in this coffee bean roasting device is a short gutter-shaped ceramic body made of high heat shock-resistant ceramics such as cordierite porcelain, zircon porcelain, and alumina porcelain. 1, a coiled nichrome vA2 as a metal resistance heating element is embedded uniformly in a zigzag shape at a position closer to the front side than the center of the wall thickness, and both ends of the nichrome wire 2 are placed on the back side of the ceramic body 1. It is connected to the lead wire 4 through the raised mounting part 3, and the nichrome wire 2 is connected to the front of the ceramic body 1.
In order to increase the radiation of infrared rays by increasing the thickness of the ceramic body 1 on the front surface of the ceramic body 1, uneven stripes 5 are formed to accommodate the embedded nichrome wire 2.

In addition, in order to manufacture such a structure, for example, M g O 10.1%, which becomes cordierite porcelain.

Al2O228.5%, 5loz 54.5%, Kz
o 0.5%, N-to 0.1%, C,01
,8%.

A rough base material containing 1.5% TIO, 0.3% F, and 0.3% richness was purified, and a 200W coiled nichrome wire 2 was embedded near the front side using the casting method, formed as described above, and then fired. Ru. For example, if the area of the front surface of the ceramic body 1 is set so that the surface power density is approximately I W/Cl11, then 2
When a current of 00 W is applied, as shown in FIG. 3, there are peaks in the vicinity of wavelengths of 3 μ and 5 to 8 μ. Emit long wavelength infrared rays.

On the other hand, as shown in Figure 4, the infrared absorption spectrum of coffee beans has an absorption rate of 50% at most of the wavelengths shown.
% or more, especially when the wavelength is 3μ, 5.7μ,
It shows a high value around 8.3μ.

This shows that the infrared rays emitted from this infrared heater are absorbed by the coffee beans with a very high absorption rate. The temperature of this infrared heater is approximately 400℃ in order to match the infrared absorption spectrum of the coffee beans.
It is desirable to set the temperature to ~700°C.

In addition, this infrared heater has a series of coiled nichrome wires embedded uniformly in a zigzag pattern in a short gutter-shaped ceramic body with high thermal shock resistance, so it can withstand long-term energized use. There is no risk of scratches, and it is resistant to moisture.The thickness of the ceramic body is uniform in series on the front side of the coiled nichrome wire, and infrared radiation is emitted in large quantities and efficiently. It has a larger heat capacity and is less likely to cool down.

Therefore, the coffee bean roasting apparatus of the present invention uses the above-mentioned infrared heater as a heat source, and the coffee beans are heated to a wavelength 3 of the infrared heater.
It is equipped with means for stirring in the infrared irradiation range of ~10μ.

The roasting apparatus shown in FIGS. 5 and 6 is of a rotating drum type, and a furnace body 7 supported on a frame 6 is formed of a heat insulating material, and its inner wall surface 8 is cylindrical. The lower surface 9 is open, and bearings 12 are provided on both side walls 10.11.
．． 13, a rotating shaft 14 is horizontally supported on the bearing 12.13, spokes 15 are formed radially around the outer periphery of the rotating shaft 14, and a rotating drum 16 is supported by the spokes 15. It has a cylindrical shape with one end open, and the open end 17 approaches and opposes the inner surface of the side wall 10,
The gap is adjusted to 1 to 2 cm to prevent coffee beans from falling.

The rotating drum 16 is made of a so-called punching metal, and has a large number of small holes (round holes) with an aperture ratio of 20.
I'm trying to keep it at ~70%. Note that the rotating drum 16
One end of the 0-rotation shaft 14, which has a large number of small holes through its peripheral wall as well as the end wall 1B, projects outside the furnace body, and a sprocket 19 is fixed to the projecting portion. Approximately three spiral blades 23 are arranged on the inner periphery of the 0-rotation drum 16, which connects the sprocket 19 with the sprocket 21 provided on the motor 20 with a speed reducer fixedly attached to the frame l by an endless chain 22. It is permanently installed. The infrared heater 24 is mounted on the inner peripheral surface 8 of the furnace body 7 so as to surround the rotating drum 16 and as close to the outer periphery of the rotating drum 16 as possible, so that the infrared rays can be efficiently transmitted into the rotating drum 16. It is made to radiate. In addition, the side wall 11
A plurality of similar infrared heaters 24 are arranged on the inner surface of the rotating drum 16 so that infrared rays can be radiated into the drum through a large number of small holes formed in the end wall 8 of the rotating drum 16. 25
26 is an inlet for green coffee beans, and an outlet for extracting roasted beans.

In this roasting device, a rotating drum 1 is driven by a motor 20.
6 stirs the coffee beans charged in the drum, and infrared rays are irradiated from the infrared heater 24 through the many small holes of the drum 16. For this reason, the coffee beans inside the drum are evenly irradiated with infrared rays and the temperature rises evenly to the inside of the beans, achieving a very high quality roasted state in a short time.

The roasting apparatus illustrated in FIG. 7 is of a continuous furnace type, and this infrared heater 24 is provided in a furnace body 32 equipped with an inlet 30 and an outlet 31, and a mesh belt conveyor 3 is provided.
The coffee beans are carried into the furnace by the conveyor 33 and irradiated with infrared rays. This conveyor 32 has a vibrator 3.
4, the coffee beans are vibrated on the conveyor 33 during infrared irradiation to change the direction of the coffee beans, so that the infrared rays are evenly irradiated.

Equipment that continuously roasts coffee beans in this way is for commercial use, but the roasting equipment shown in Figure 8 is suitable for home use and can process a small amount of coffee beans. Coffee beans are placed in a pot 36 equipped with stirring blades 35 that are rotated at low speed by a motor, and an infrared heater 24 is provided on the ceiling of the pot to face the coffee beans.
The coffee beans in the pot 36 are stirred by the stirring blades 35 and roasted using the infrared heater 24 as a heat source. Note that 37 indicates a coffee bean outlet provided at the bottom of the pot 36. By opening this door 38, the roasted coffee beans in the pot 36 can be extracted in a short time.

As shown in these embodiments, the present invention can specifically consider various roasting apparatuses using the infrared heater 24 as a heat source, but in addition to these embodiments, as a means for stirring coffee beans, For example, coffee beans may be placed on a wire mesh, hot air blown through the wire mesh upwards, and the coffee beans may be swayed by the wind pressure.

In addition to the infrared heaters according to the present invention, there are conventional infrared heaters on the market that are made by coating the surface of a rod-shaped quartz tube or sheathed heater with various infrared radiators.
Table 1 shows the results of coffee extraction and tasting for coffee beans roasted using commercially available infrared heaters A, B, and C as a heat source and coffee beans roasted using the infrared heater of the present invention as a heat source.

The above evaluation method ranks the taste in the order of very good, good, and bad, with 3 points for very good, 2 points for good, and 1 point for bad, based on the total score of 20 panelists. The milk-containing type in Table 0, which shows superiority and inferiority, is for canned coffee and contains 835 g of coffee extract, 100 g of milk, and 165 g of sand.
, black.

The sweetened type is coffee extract 935. g Nisuna I!
65 g. Also, for regular coffee, 20g of ground beans and 300ml of 95℃ hot water! It was extracted using a paper filter.

As a result, the roasting device of the present invention was not only excellent as regular coffee but also excellent as a material for canned coffee.

Further, Table 2 shows the comparison results of the preservability of each coffee in Table 1.

(+: Good, ±: Somewhat good, -: Significantly deteriorated, -: Completely deteriorated) As described above, the coffee according to the present invention has a remarkable difference in its shelf life compared to coffee using other heat sources. It was observed.

〔Effect of the invention〕

As explained above, according to the coffee bean roasting apparatus according to the present invention, heat can penetrate deeply and evenly into the inside of the coffee beans, and the original taste and aroma of the coffee beans can be successfully brought out. It also has beneficial effects such as improving the shelf life of the coffee.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a partially cutaway front view of an infrared heater according to the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a spectral distribution diagram of the infrared and wire heater. , Fig. 4 is for infrared absorption spectrum lines of coffee beans, Fig. 5 is a vertical cross-sectional view of a rotary drum type roasting device, and Fig. 6 is a line taken from nn in Fig. 5.
7 is a vertical sectional view of a continuous roasting device, and FIG. 8 is a vertical sectional view of a small-sized roasting device. DESCRIPTION OF SYMBOLS 1... Ceramic body, 2... Nichrome wire, 5... Uneven stripes, 24... Infrared heater. Patent applicant: Pokka Corporation Figure 4 Figure 3 Figure 3 Figure 6

Claims (1)

[Claims] Coiled nichrome wires are embedded uniformly in a zigzag pattern in a short gutter-shaped ceramic body with high thermal shock resistance, and on the front side of the ceramic body, a series of nichrome wires are arranged so that the thickness of the ceramic body on the front side is uniform. A coffee bean comprising means for forming uniform unevenness, irradiating the coffee bean with infrared rays with a wavelength of 3 to 10μ emitted from the front surface of the ceramic body, and stirring the coffee bean. Roasting equipment.