JPH02276538A - Preparation of rice cake - Google Patents

Abstract

PURPOSE:To prepare a rice cake free from blister and warpage and having uniform thickness by applying high-frequency heating and hot or cold air to an externally heated rice cake dough, expanding and baking the above preheated dough and further baking the dough to develop the color. CONSTITUTION:A rice cake dough is supplied on to a belt 3 and introduced into a preheating oven 100 composed of a burner 10A as an external heating means 10 and a high-frequency heating means 50. The dough is heated with high-frequency wave and, at the same time, preheated with hot or cold air blasted from an air-feeding port 11. The preheated dough is introduced into an expansion oven 30 and subjected to expansion treatment for 1-2min under the pressing force of the upper and lower pressing rolls 34, 34. The expanded rice cake dough is colored in a color-developing oven 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing rice crackers, and particularly to an improved method for preheating rice cracker dough.

[Conventional technology]

Conventional methods for mechanically continuous production of rice crackers generally involve placing the rice cracker dough on a belt conveyor that passes through a long continuous baking kiln, and heating it continuously with gas burners from above and below at the same time to prevent coloring. It was being fired.

However, with this conventional method, the baking time is long, so the rice cracker dough may warp (localized swelling caused by blisters), lose its shape and not be finished flat, or even cause blisters. It had drawbacks such as being unable to be baked hard because it was allowed to slow down. Therefore, in order to shorten the baking time, increase the puffing rate, and make the puffing uniform, a method was developed that uses high frequencies to make rice crackers. As a means of producing rice crackers using high frequency heating, for example, the method described in Japanese Patent Publication No. 15665/1983 is known, and this method uses rice grains as the main ingredient of puffed rice crackers in the presence of water. , heat, crush, and knead to obtain a viscous homogeneous material with a degree of gelatinization of 60% or more. After molding this into an appropriately large size, it is preheated and dried to reduce the moisture content to 10 to 20%.
%, and then heat this pre-dried material from the inside using high-frequency heating to swell it and heat it until the moisture content becomes 3% or less. Also, for the same purpose, JP-A-50-42
The one described in Publication No. 064 was also developed.

[Problem to be solved by the invention]

With these conventional techniques of baking dough using high-frequency heating, it is possible to obtain a desired degree of puffiness in a short period of time, but in terms of flavor, it is inferior to external heating methods using electric heat, gas, etc. The finished product had a ``powdery'' feel to it and lacked the aromatic flavor characteristic of rice crackers.

Therefore, the purpose of the present invention is to achieve a desired degree of expansion in a short time without losing flavor even when high-frequency heating is applied, to easily produce cracked rice crackers, and to shorten the preheating time. shall be.

[Means to solve the problem]

The present invention has been made to achieve the above objects,
The gist of this is that in the method of manufacturing rice crackers by preheating rice cracker dough, expanding and baking it, and then coloring and baking it, the rice cracker dough is subjected to external heat treatment, and then high-frequency heating and hot or cold air are applied. In addition, it is necessary to preheat.

[For production]

When preheating the dough in this way, the dough is first subjected to external heat treatment to soften the dough surface and form a thin skin, and then when high-frequency heating and hot air are subsequently applied, the temperature on the dough surface and inside is uniform. Therefore, the water content distribution throughout the dough can be made uniform, and therefore the whole dough can be uniformly softened. This effect was extremely difficult to achieve with conventional methods that used only external heat as a preheating means. If this softened dough is puffed and baked, it will not puff up or warp, and you will get rice crackers of good quality that are puffed to a uniform thickness.

Furthermore, when high-frequency heating and cold air are applied at the same time after external heat treatment, only the surface of the dough is cooled, making it possible to bake a special type of rice cracker called cracked rice crackers, in which fine cracks appear on the surface of the dough.

〔Example〕

A rice cracker baking apparatus configured to carry out the present invention will be described below.

As shown in Figures 1 and 2, the driven roller 2 on the entrance side
and a drive roller 1 on the exit side, and these rollers 1.
An endless belt 3 with a width of about 91 (tea) is suspended between the rollers 2 and 2. Reference numeral 4 in the figure is a drive source for rotating the drive roller 1. The rice cracker dough is transferred from the right hand direction to the left hand direction in the figure by a belt conveyor consisting of a belt 3 and a drive source 4, and along the transfer direction, an external heat treatment means 10, a high frequency heating section 20, a puffed black part 30°, a colored black part 40 is sequentially coated.Furthermore, an upper belt conveyor 5 is provided above the above-mentioned belt 3 from the expanded black part 30 to the colored black part 40, and the belt of this upper belt conveyor 5 also overlaps with the above-mentioned belt 3. It is configured in the same way as .

Further, the external heat treatment means 10 and the high frequency heating section 20 are devices that preheat the rice cracker dough, and these are collectively referred to as the preheating window section 100.
That's what it means.

The external heat treatment means 10 has a large number of air supply holes 11 arranged below the belt 3, and hot or cold air is blown onto the rice cracker dough from the air supply holes 11 while the dough is softened by the gas burner 10A. That is, the surface of the dough is softened in the external heat treatment means 10 to form a thin skin. The gas burners 10A are disposed above and below the belt 3, and both the upper and lower flames are configured to be movable up and down.

Although not shown, the high-frequency heating unit 20 is equipped with two high-frequency heaters above the belt 3, and has air holes below the belt 3 so as to face these high-frequency heaters. Either hot air or cold air can be selectively sent to this ventilation hole from an external ventilation source. Moreover, high frequency waves for heating are guided to the high frequency heating machine via a waveguide 28 from a high frequency generator installed outside.

Note that both the external heat treatment means 10 and the expanded black part 30 are configured so that air from an air source can be blown out from the air supply holes 11.33. Furthermore, filter zones 50 and 50 are formed between the external heat treatment means 10 and the high-frequency heating section 20, and between the high-frequency heating section 20 and the expanded black part 30, respectively. This filter zone 50.50 is for absorbing 245 OMHs radio waves used in high frequency heating to prevent them from leaking. and filter zone 5
The inside of the 0.50 is constructed to absorb radio waves by passing water through a thin tube, in order to cool it down as the internal temperature rises.

Note that the expansion window portion 30 and the colored black portion 40 are also provided with gas burners, electric heaters, etc. 30A and 40A, respectively. Furthermore, a press roll 34 is provided inside the puffing window 30, and this roll presses the dough from above and below so that the dough does not warp or the like when it is puffed.

In addition, gas burners 10A, 30A, and 40A are installed in each kiln, and gas collecting pipes 10B, IOB, and 3 in each upper and lower burner.
Piping 0B, 30B, 40B, 40B, and each gas collecting pipe 10B, 10B, 30B, 30B, 40B, 40B
Attach a gas compression regulator shown as R in Figure 2 to the population of 2, so that even if the source pressure of gas supply fluctuates, the pressure inside the gas collecting pipe (10B etc.) will not fluctuate and the pressure will be adjusted. This makes it easy to adjust the firepower for each kiln.

Next, a method for producing hard-baked rice crackers by baking rice cracker dough using the apparatus configured as described above will be described.

First, the dough is supplied onto the belt 3, and the dough on the belt 3 is preheated in the preheating black section 100 for about 2 to 6 minutes to soften it. At this time, in the high-frequency heating section 20, when hot air is sent from the air hole, the hot air and high-frequency heating work together to uniformly expand the dough and remove the "flouriness". On the other hand, when sending cold air, the dough preheated by the burner 10A of the external heat treatment means 10 is cooled and subjected to high frequency heating, so that "cracks" occur in the dough and the inside of the dough is heated by high frequency heating, causing "cracks". It becomes easy to bake rice crackers, etc.

If the water content of the rice cracker dough becomes 25% or less in the above preheating stage, it will be difficult to dry it using external heat treatment using electric or gas heat, but if high-frequency heating and hot or cold air are applied to the rice cracker dough with a moisture content of 25% or less, Not only is drying possible, but the time can also be shortened. That is, in the high-frequency heating section 20, the moisture content of the rice cracker dough is reduced to 12% or less in a short time, and the inside of the dough is dried and pre-baked, and no "flouriness" remains. Next, in the expansion window section 30, the dough is sandwiched between upper and lower conveyor belts and pressed by upper and lower presser rolls 34, 34, so that so-called sandwich baking is performed to uniformly increase the thickness of the dough. Note that the processing time in this expansion window section 30 is about 1 to 2 minutes.

Next, the rice cracker dough is sent to the colored black section 40, where it is heated to about 1.5 to 4
Processed for minutes. The overall processing time for hard-baked rice crackers and the like was about 5 to 12 minutes, although it varied depending on the thickness of the dough.

Furthermore, according to the above-mentioned apparatus, the preheating black part 100 and the swelling window part 3
Since hot or cold air is blown onto the rice cracker dough in the oven, in other words, the rice cracker dough is exposed to outside air and baked, thereby further suppressing the generation of puffs.

Moreover, although the preheating black part 100 and the colored black part 40 each consist of a plurality of ovens, an appropriate gap is provided between each window.

The colored black part 40 indicates that each kiln has a gas burner 4 only in the upper part.
The kiln provided with 0A and the kiln provided with the gas burner 40A only on the lower surface may be discontinuously arranged, or all the kilns may be provided with the gas burner 40A on the upper and lower sides.

〔Effect of the invention〕

As explained above, in the present invention, not only high-frequency heating is simply applied to the rice cracker dough during preheating, but hot air or cold air is blown simultaneously with the high-frequency heating. Moreover, since the rice cracker dough is externally heat-treated before applying high-frequency heating, the surface of the dough is first softened to form a thin skin on the surface of the dough, and then the inside is heated by high-frequency heating, which allows the surface of the dough and the inside of the dough to be softened. The process can be uniformly softened, and the time previously required for preheating can be significantly shortened, resulting in a reduction in overall processing time. Furthermore, in this invention, since high-frequency heating is performed after being heated to a certain extent by external heat treatment, the high-frequency oscillation output is also relatively low < (5
(Kw) is fine.

Furthermore, if hot air is added during high-frequency heating, the temperature of the dough surface becomes the same as the internal temperature, and high-frequency heating can be applied to the inside of the dough without cooling the dough surface, so the surface and inside of the dough are even closer together. It becomes uniform and produces a good product without warping or blistering.

Additionally, when cold air is applied, fine cracks can be created in the crust on the surface of the dough, making it easier to bake special products.

[Brief explanation of drawings]

Figure 1 is a side view of a device that realizes the present invention, and Figure 2 is a side view of the device that realizes the present invention.
FIG. ■... Drive roller 2... Driven roller 3... Belt 4... Drive source 5... Upper belt conveyor IO... ... External heat treatment means 11.33 ... Air supply hole 2θ ... High frequency heating section 2 ... Waveguide 3 ...... Swelling black part 34 ...・Press roll 40...Colored black part) Filter zone 10θ...Preheating black part

Claims (1)

[Claims] (1) In the method of producing rice crackers by preheating rice cracker dough, expanding it, baking it, and then coloring and baking it, the rice cracker dough is subjected to external heat treatment, and then preheated by high-frequency heating and hot or cold air. A method for producing rice crackers characterized by the following.