JPH0856589A - Method for preheating and steaming under pressure in continuous steaming treatment under pressure and apparatus for steaming under pressure - Google Patents

Abstract

PURPOSE: To prevent the unevenness of thermal history from occurring by carrying out the previous heat treatment of a granular or a powdery raw material in saturated steam and steaming treatment thereof under pressure in the saturated steam and a dispersed state in continuous steaming treatment under pressure of the raw material. CONSTITUTION: This method for preheating a raw material is to retain the raw material in a stirred state in a saturated steam atmosphere with a preheater and then transfer the raw material without mixing air therein to steaming treatment under pressure. Furthermore, this method for steaming under pressure is to convert the preheated raw material into a dispersed state in a saturated steam atmosphere under the steaming pressure with a steaming apparatus and then deposit and retain the resultant material. This steaming apparatus under pressure is equipped with a means for dispersing the preheated raw material in the saturated steam atmosphere under the steaming pressure and a means for depositing and transferring the raw material after the dispersion thereof.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is for continuous pressure steaming of granular or powdery raw materials consisting of rice, wheat, soybeans, grains such as corn, foods such as spices, especially defatted soybeans in soy sauce production. Preheating method, pressure steaming method and apparatus therefor.

[0002]

2. Description of the Related Art A conventional continuous pressure steaming method will be described by taking defatted soybean in soy sauce brewing as an example. First, 135% by weight of warm water (80 ° C.) is sprinkled on the defatted soybean while stirring. Next, the defatted soybeans are preheated to about 95 ° C by adding steam in a preheating screw. The pressure steaming device has a structure in which the inlet and outlet of the raw material can be sealed with a rotary valve, and the preheated defatted soybeans put in a saturated steam atmosphere (1.8
kg / cm ² G) is retained for 3 minutes to perform pressure steaming treatment. Immediately after boiling, the defatted soybeans discharged are cooled to about 40 ° C with a cooler. This pressure steaming treatment is aimed at sterilization and heat denaturation so that soybean protein is easily enzymatically decomposed.

In the continuous pressure steaming method, it is important to uniformly raise and keep the temperature of the raw material. If this is lacking, N- and S-characteristics (acetic acid stain) due to undenaturation can be seen in the treated raw material,
Over-denaturation occurs and the nitrogen dissolution utilization rate decreases. Normally, the preheated raw material is fed to the pressure steaming device through a rotary valve, but in Japanese Patent Publication No. 55-25817 (grain cooking method), the preheated raw material to be fed into the pressure steaming device is fed by a high-speed air stream. A method is proposed in which the temperature is raised after being dispersed, and the temperature is transferred into a heated gas to keep the temperature. This is because the raw material to be nodular is dispersed by a high-speed air flow, and it is in units (in defatted soybeans, one grain)
Is directly contacted with water vapor to enable the temperature rise for a short time, and the state is maintained.

[0004]

The problem from the preheat treatment to the pressure steaming treatment is that the heat history of the raw material is uneven (including the uneven temperature distribution of the raw material), which causes a difference in the degree of denaturation between the raw materials. Is. For example, if there is this unevenness, an unmodified raw material will be produced if the treatment is performed in accordance with a material that is rapidly denatured, and conversely, an over-denatured raw material will be produced if it is processed in accordance with a material that is slowly denatured. The above proposal is an example of improving these problems in a steaming process. However, the above-mentioned problem has already appeared in the preheat treatment, and the problem appearing in this preheat treatment stage is considered to have an influence on the steaming process. Therefore, it is necessary to take measures against uneven heat history in each of the preheat process and the steaming process.

At the stage of pre-heat treatment, there are places where the temperature is locally low in the raw material, and thermal history unevenness often occurs.
This is due to air mixed between the raw materials. Conventionally, no attention has been paid to the air existing between the raw materials, but at a preheating temperature of about 95 ° C, air is mixed with the steam depending on the ratio of the partial pressure to the steam at the atmospheric pressure and the raw materials are mixed. Is supplied to. Since air originally has an adiabatic action, it is considered that the portion where air exists between the raw materials cannot be heated by steam as expected. Therefore, when air is mixed between the raw materials and transferred from preheat treatment to pressure steaming treatment, heat history unevenness occurs even in pressure steaming treatment, and unmodified (slow steaming treatment) or over-modified (steaming). The ones that process faster) occur.

Next, at the stage of pressure steaming treatment, conventionally, the preheated raw material is put into the pressure steaming apparatus in a state of being compressed by a preheating device, a rotary valve or the like, so that the internal and external temperature rising process of the whole raw material is performed. There is a problem in that the heat history becomes non-uniform due to the difference in temperature. This is a problem that occurs because the lumped preheated raw material is heated from its surface only by heat conduction. Therefore, it is preferable to disperse the preheated raw material to be charged as seen in the above proposal, but since a pressure higher than the cooking pressure is required to generate the high-speed air stream under the cooking pressure, the high-speed air stream is inevitable. In addition, the temperature is higher than the saturated steam, which is the boiling temperature, and the temperature difference between the raw material unit, for example, the surface and the inside of defatted soybean is larger than that without high-speed airflow, which promotes uneven heat history. .

From the above consideration, firstly, the preheat treatment is reviewed so that the mixture of steam and air can be avoided to realize the preheating by only saturated steam so as not to cause uneven heat history. After reviewing the treatment, disperse the preheated raw material in the saturated steam atmosphere at the steaming pressure and put it into the device, and make sure that the unit of the raw material, that is, defatted soybean, can maintain a space between each grain, and saturated steam It was decided that the preheating method, the pressure cooking method and the pressure cooking apparatus should be studied, with the objective of quickly permeating into the raw material and steaming so that uneven heat history does not occur.

[0008]

As a result, in the continuous pressure steaming treatment in which a granular or powdery raw material is preheated and then continuously steamed under pressure, the developed material is preheated into a saturated steam atmosphere. A preheating method characterized by shifting to pressure steaming without mixing air after it is retained in a stirring state, after preheating the raw material in a steaming device in a saturated steam atmosphere at a steaming pressure, and then depositing The method is a pressure steaming method characterized in that it is retained.

Some pressure steaming apparatuses have means for dispersing the preheated raw material in a saturated steam atmosphere at a steaming pressure, and means for depositing and transferring the raw material after the dispersion. Dispersion of the preheated raw material in the steaming treatment is preferably performed by utilizing mechanical movement, and specifically, a stirrer for rotating a stirring rod, a paddle screw, or the like is used.

[0010]

The preheating method and the pressure steaming method of the present invention are carried out in a saturated steam atmosphere under respective pressures of preheat treatment and pressure steaming treatment (at atmospheric pressure in the preheat treatment and steaming pressure in the pressure steaming treatment). By doing so, it is possible to heat the raw material that has eliminated the harmful effects of air or the preheated raw material. In the preheat treatment, by eliminating the inclusion of air and heating the raw material while stirring in a saturated steam atmosphere at atmospheric pressure, 10
Achieve uniform preheat to reach 0 ℃. Further, since there is no air having a heat insulating effect, the time required for raising the temperature can be shortened. Furthermore, by moving the raw material to the pressure cooking process without mixing air, it is possible to prevent the harmful effects of air from occurring at the stage of the pressure cooking process and to secure a uniform heat history.

In the pressure steaming treatment, the preheated raw material is
By dispersing with a stirrer or the like in a saturated steam atmosphere of cooking pressure, a space is created between the raw material units, for example, one grain of defatted soybeans, and even when defatted soybeans are deposited on the net conveyor. By maintaining the space, uniform heating and heat history of the entire raw material can be achieved. In the dispersion of the raw material using the proposed high-speed airflow exemplified above, even if the dispersion of the raw material is attempted in a saturated steam atmosphere at a cooking pressure,
As a result of requiring a pressure higher than the steaming pressure to generate a high-speed air stream, the temperature of the air stream inevitably exceeds the steaming temperature, and the steaming pressure is not dispersed in a saturated steam atmosphere, and this stream There will be a large difference in the thermal history between the surface of the defatted soybeans and the inside of the colliding raw material units. However, when a stirrer or the like is used, since there is no locally high temperature, it becomes possible to disperse the raw materials in a saturated steam atmosphere at a steaming pressure, and the difference in the heat history becomes small, and the entire raw material is reduced. The thermal history is almost uniform.

[0012]

EXAMPLES Examples using the preheating method and pressure steaming method of the present invention will be described below with reference to the drawings. FIG.
Is a configuration diagram of a watering device 1, a stirring preheating device 2, a retention device 3 and a continuous pressure cooking device 4 for treating defatted soybean for soy sauce brewing, which uses the preheating method and the pressure cooking method of the present invention. Is. The defatted soybean that is a raw material that has been input from the input port 5 of the water sprinkling device 1 is sent to the stirring preheating device 2 while being stirred with warm water by the paddle screw 6 and is preheated in a saturated steam atmosphere under atmospheric pressure, and the retention device. It is put into the pressure cooking device 4 without mixing the outside air from 3. The charging port 7 and the discharging port 8 of the pressure steaming device 4 are isolated by a rotary valve 9, and directly below the rotary valve 9 of the charging port 7.
A dispersing device 10 is provided as a means for dispersing the preheated raw material.

The configuration and operation of each device will be described with reference to FIG. The sprinkler 1 is a device for sprinkling warm water onto defatted soybeans to swell them, and has a built-in paddle screw 6 driven by a motor 11. This sprinkling treatment corresponds to the pre-treatment of the preheat treatment, and 135% by weight of warm water of 80 ° C. is sprinkled on the defatted soybeans transferred while being stirred by the paddle screw 6. Excess steam is exhausted from the exhaust steam fan 12. The defatted soybeans sprinkled with water are sent to the stirring preheating device 2 through the closed connecting path 13.

The stirring preheating device 2 has a built-in paddle screw 15 driven by a motor 14, and the staying device 3 has a built-in screw conveyor 17 driven by a motor 16, both of which perform preheat treatment together. In addition, the steam is connected to both devices.
The air in the raw material is driven to the sprinkler 1 and exhausted. The defatted soybeans sprinkled with water are stirred by a preheating device 2
By passing through a saturated steam atmosphere in the absence of air while being agitated, the temperature is uniformly raised in a short time, and the preheat treatment is realized by staying at the reached temperature.
The stirring preheating device 2 rotates the paddle screw 15 at 50 rpm to retain the defatted soybean for 3 seconds, and the retention device 3 rotates the screw conveyor 17 at 4 rpm to retain the defatted soybean for 5 minutes. The former has a short residence time because the purpose is to eliminate the air between the raw materials, and the latter has a long residence time because the purpose is to reach the preheat temperature of the raw material and to uniformly swell with the sprinkled water.

In the conventional preheat treatment, since the preheat temperature is set to about 95 ° C., air corresponding to the ratio of the partial pressure with steam exists between the raw materials as described above, and it takes time to raise the temperature. Occurrence of unevenness or uneven heat history during preheating. Even if 100 ° C. steam is supplied into the preheating device, if the preheating temperature is less than 100 ° C., air still exists and a saturated steam atmosphere cannot be realized, and the same problem as described above occurs. However, in the preheating method of the present invention,
Since the presence of air is excluded, the temperature of water vapor = ambient temperature, that is, with saturated steam of 100 ° C, the ambient temperature is also 100 ° C.
Therefore, the problem of heat history unevenness in the pre-heat treatment of the raw material is solved, and eventually the generation of N- and S-characteristics after the pressure steaming treatment is suppressed, and conversely, over-denaturation is also prevented.

The defatted soybeans that have been preheated are retained in the retention unit 3.
Is sent to the pressure steaming device 4 via the rotary valve 9. As can be seen in FIG. 1, the path 19 through which the defatted soybeans are transferred is hermetically sealed so that air is not mixed in during the passage. Whether the raw material actually stays in a saturated steam atmosphere in a stirred state, that is, whether the stirring preheating device 2 is filled with saturated steam is determined by whether or not the temperature sensor A indicates 100 ° C. Also, regarding the inclusion of air, it is judged whether or not the temperature sensor B indicates 100 ° C. Agitation preheating device 2, retention device 3
The processing path from the pressure steaming apparatus 4 to the pressure steaming apparatus 4 is all in a saturated steam atmosphere, but since the pressure inside the pressure steaming apparatus is different between the former two and the pressure steaming apparatus, the rotary valve 9, 9 are isolated. The pressure steaming device 4 is a device having a built-in net conveyor 20 as a means for depositing and transferring the preheated raw material in the casing, and transfers the preheated defatted soybeans in a saturated steam atmosphere at the steaming pressure and stays at the steaming temperature. To realize.

Immediately below the charging port 7, a dispersing device 10 consisting of a stirrer 21 with stirring rods intersecting each other is installed as a means for dispersing the preheated raw material, and the preheated defatted soybeans falling from above are saturated with the cooking pressure. It is dispersed in a steam atmosphere and deposited on the net conveyor 20. As a result, the defatted soybeans that have been agglomerated are separated into individual soybeans, and are easily heated by saturated steam. Even if the defatted soybeans once dispersed are accumulated in a lump form on the net conveyor 20, the space between the individual soybeans is maintained and air does not exist, so that the temperature reaches the predetermined temperature promptly.

On the other hand, as shown in FIG. 2, when the means for transferring the preheated raw material in the continuous pressure steaming apparatus 22 is constituted by the screw conveyor 23, even if the preheated defatted soybean is dispersed at first. Since the screw conveyor 23 is compressed during transfer, heating on the screw conveyor 23 is slow, and heat history unevenness may occur. Therefore, it is sufficient to provide a temperature reaching step constituted by a dispersing device 25 including a paddle screw 24 as a preceding stage so that the defatted soybeans can reach a predetermined temperature sufficiently, and the screw conveyor 23 may perform only the heat retaining step.

Next, the defatted soybeans subjected to pressure steaming treatment with the apparatus of this embodiment were compared with the defatted soybeans treated by the conventional treatment method. Table 1 shows that steaming pressure of 100 ℃ was preheated and steaming pressure was 1.8kg / cm ² G for 3 minutes in principle.
The experimental results of measuring N-, S-, and nitrogen-dissolving utilization rate of the defatted soybeans subjected to pressure steaming treatment in Table 2 are shown in Table 2. N and S of defatted soybeans that have been steamed under pressure for 3 minutes
It is an experimental result which measured the sex and the nitrogen dissolution utilization rate.
Both fermentation and ripening are carried out by conventional methods.

[0020]

[Table 1]

[0021]

[Table 2]

In the preheat treatment, as shown in Table 1, in the conventional preheating method, the temperature sensor A (see FIG. 1) and the outlet at the inlet of the preheating process are used even though the steam of 100 ° C. is fed. Both temperature sensors B (see Fig. 1) at 100
It has not reached ℃. This indicates that air is present in the raw material and a partial pressure between air and water vapor is generated, which means that preheating in a saturated water vapor atmosphere is not performed. As a result, N-type and S-type are observed in the conventional preheating method, and if the pressure cooking time is increased in order to eliminate the N-type and S-type, the nitrogen dissolution utilization rate is lowered.
In the preheat treatment of the present invention, both temperature sensors A and B are 100 ° C., which shows that a saturated steam atmosphere is realized.
In the apparatus of the present embodiment, it is possible to obtain N, S and
The results show that the nitrogen dissolution utilization rate is 93%, which is a good result.

In the pressure steaming treatment, as shown in Table 2, in the conventional method having no dispersing device, S property was observed even if the temperature of the preheated raw material was 100 ° C. The rate is low. However, when the pressure cooking time is increased to eliminate this S property, the problem of over-denaturation occurs. On the other hand, in the case of combining the preheating method and the pressure cooking method of the present invention, the center of the preheated raw material deposited in the pressure cooking apparatus is heated from the temperature 100 ° C to the pressure cooking temperature 130 ° C. The time is very short, about 3 seconds. Therefore, it is considered that a sufficient steaming treatment is completed in a pressure steaming time of 3 minutes, S characteristics are lost, and the nitrogen dissolution utilization rate reaches a good result of 93%.

[0024]

EFFECT OF THE INVENTION In the preheating method, the pressure cooking method and the pressure cooking apparatus of the present invention, the air between the raw materials is discharged in the preheating step to eliminate the harmful effects of the air in the preheating step and the pressure cooking step, and to apply the pressure. By dispersing the raw material in a saturated steam atmosphere in the steaming step and subjecting the raw material to pressure steaming, the raw material can uniformly reach a predetermined temperature in a short time, and good processing can be performed. Pressurized steaming is an important step that determines the quality of the final product, such as determining the quality of soy sauce for defatted soybeans. You will be able to offer the product.

Further, the presence of air in the treatment process has been a factor that causes the theoretical treatment time, the treatment temperature and the actual condition to deviate from each other, but in the method of the present invention,
By making the difference between the two as small as possible, it becomes easy to automate the device, such as predicting the result of the steaming process or predicting the setting for performing the desired steaming process in advance. As a result, the operating cost of the device and the labor of the operator can be reduced. Further, since the processing time is shortened, the amount of processing per unit time is increased, and as a result, the device can be downsized.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a continuous pressure cooking apparatus using a preheating method and a pressure cooking method of the present invention.

FIG. 2 is a block diagram of a continuous pressure steaming device in which the dispersing device is a paddle screw.

[Explanation of symbols]

 1 Water sprinkler 2 Stirring preheater 3 Retention device 4 Continuous pressure steamer 10 Disperser 20 Net conveyor 22 Continuous pressure steamer 25 Disperser

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location A23L 3/015 3/22

Claims (3)

[Claims] 1. In a continuous pressure steaming treatment in which a granular or powdery raw material is preheated and then continuously steamed under pressure, after the raw material is retained in a saturated steam atmosphere in a stirring state by a preheating device, air is then aerated. A preheating method, characterized in that the process proceeds to a pressure steaming process without being mixed with. 2. In a continuous pressure steaming treatment in which a granular or powdery raw material is preheated and then continuously steamed under pressure, a preheated raw material is dispersed in a saturated steam atmosphere at a steaming pressure with a pressure steaming device. The method of steaming under pressure is characterized by the steps of: 3. In a continuous pressure steaming treatment in which a granular or powdery raw material is preheated and then continuously steamed under pressure, means for dispersing the preheated raw material in a saturated steam atmosphere at a steaming pressure, and after the dispersion. A pressure cooking apparatus comprising means for depositing and transferring the raw material.