JPS5832979B2 - Continuous microwave frying equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous microwave frying device, and an object of the present invention is to suppress microwave loss in oil and increase microwave absorption efficiency of heated materials.

In general, in continuous microwave frying equipment that heats objects in oil with microwaves, most of the microwave energy is absorbed by the oil because the dielectric power factor of the food is significantly larger than that of oil. Therefore, even if the food is thick, it has the advantage of being able to deep-fry the center of the food in a short time without burning the surface.

However, in such a frying device, when the food is frozen, the dielectric power factor of the frozen food is small and there is no difference from the dielectric power factor of the oil, so the microwave energy is evenly absorbed by the frozen food and the oil. Therefore, the heating efficiency deteriorates and the oil temperature rises, making it difficult to adjust the oil temperature.

This invention has been made in view of this point, and one embodiment will be described below.

1 is a microwave heating chamber, 2 is a well-known microwave generator such as a magnetron, 3 is a waveguide for guiding the microwave generated by the microwave generator to the heating chamber 1, and 4 is a drive roller made of Teflon. and a conveyor belt 5 made of a heat-resistant material such as silicone, for conveying the fried food from the heating chamber 6 toward the heating lower part; 8 and 9 are the heating chamber 6; and a trap provided in the heating evacuation lower to prevent microwave leakage from the inlet 6 and the outlet lower.

The traps 8 and 9 are constructed by disposing radio wave absorbers 8b and 9b in passages surrounded by radio wave shielding walls 8a and 9a.

10.11 is the mesh conveyor belt 5 in the heating chamber 1.
The nozzles 12, 13, .

The spray pipes 10 and 11 are closed at one end 10a and 11a, and the other end 10b and 11b are closed.
It is extended outside the heating chamber 1.

14 is a heat exchanger for adjusting the temperature of the frying oil sprayed from the spray pipes 10 and 11, and a heat exchange pipe (not shown) communicating with the spray pipes 10 and 11 is provided inside the heat exchanger. A heating and cooling device (not shown) for exchanging heat with the heat exchange pipe is associated with the heat exchange pipe.

15 is a pipe for recovering the frying oil after being sprayed, and a pipe L is installed at the lowest part of the bottom wall 16 of the heating chamber which is formed with an inclination.
- It communicates with the heating chamber 1 and functions to transfer oil to the filter 17 through the heating chamber bottom wall 16 and the recovery pipe 15.

18 is a pressure pump that connects the filter 1 through a circulation pipe 19.
7 and a heat exchanger 14, the recovered oil from which fried residue has been removed by the filter 17 is sucked and compressed, and the circulation pipe 1
9. It functions to spray continuously into the heating chamber 1 through the heat exchanger 14 and the spray pipes 10 and 11.

Figure 2 shows the microwave attenuation rate A when an area of length l is defined as an oil spray area and microwaves are passed through this area, and the microwave attenuation rate A when the area is filled with oil and a similar microwave Attenuation rate B is shown.

As is clear from this figure, microwave absorption in the sprayed oil state is extremely low.

In the above embodiment, the temperature and amount of frying oil can be adjusted, so that the finish of the surface of the fried food can be adjusted to a desired state.

Moreover, the spray pipes 10, 11. A spray device 20 is formed from a heat exchanger 14, a circulation pipe 19, a pressure pump 18, a filter 17, and the like.

This invention is constructed as described above, and since the oil for frying is sprayed onto the surface of the object to be heated using the spraying device, compared to a method in which the object to be heated is immersed in oil and heated with microwaves, it is possible to use frying oil. Microwave loss is small, so microwaves can be concentrated on the object to be heated and absorbed to increase heating efficiency, and the oil temperature does not rise too much, making it easy to adjust the oil temperature. play.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a curve diagram showing the microwave attenuation rate. 1...Microwave heating chamber, 4...Transfer device, 6...Heating chamber inlet, 7...Heating chamber outlet, 20...・Spraying device.

Claims (1)

[Claims] 1 A conveyance device is installed in the microwave heating chamber, the object to be heated is placed on the conveyance device, and is conveyed from the entrance of the heating chamber toward the exit of the heating chamber, and the surface of the object to be heated is covered with frying oil. The device is characterized in that it is equipped with a spray device for spraying the frying oil onto the surface of the heated object, and the surface of the heated object is covered with the mist of the frying oil. Continuous microwave frying equipment.