JP7128545B2 - Method for producing soymilk and tofu using pressure control system - Google Patents

Description

The present invention relates to a method for producing soymilk using a pressure control system without adding an antifoaming agent and producing tofu using the soymilk. A soybean milk free from offensive odor is produced by heating at an appropriate temperature without adding a foaming agent and at the same time adjusting the pressure moderately, and a coagulant is added to the soybean milk to provide a rich flavor and taste differentiated from existing tofu. to a method of making tofu having

In the production of soymilk, it is most important to remove air bubbles generated by the saponin component of soybeans during the process of boiling ground soymilk. Boiling soy milk is an essential step to heat denature the soy protein into a coagulable state. The air bubbles generated in this process not only cause the soymilk to boil over, but also impede the heat transfer in the soymilk, causing the soymilk to be undercooked, thereby deteriorating the quality of the soymilk. During the coagulation process using such soymilk, non-reaction occurs, ultimately leading to deterioration of physical properties and quality of the tofu. In addition, air bubbles remaining in the boiled raw soybean paste cause problems of separation of bean curd refuse and soymilk during the filtration process, and also interfere with the homogenization of coagulation during the coagulation process. After manufacturing tofu, air bubbles remain in the tofu and generate buoyancy, which may cause damage to the tofu during transportation, or may not be completely sterilized with hot water, causing deterioration.

Conventional methods for mass production of soymilk can be broadly divided into two types: the antifoaming method, in which an antifoaming agent is mixed with soymilk to control the generation of air bubbles during the boiling process of soymilk, and the antifoaming method, in which soymilk is heated. In order to minimize the generation of air bubbles, a sealed facility is constructed to prevent air from being sucked into the soymilk manufacturing piping, or the generated air bubbles are cooled to break them. A distinction is made between the non-defoaming agent method and the non-defoaming agent method.

Although the use of antifoaming agents that enable the production of good quality soymilk is safe and meets the strict standards of relevant laws and regulations, some false publicity and information have led food consumers to become useless. It is the actual situation that people prefer tofu using soymilk with an antifoaming agent. In response to this, many tofu manufacturers have also opted for the method of producing defoamer-free soymilk using the above-mentioned machinery or equipment.

Technologies related to the production of such antifoaming agent-free soymilk include Patent Documents 1 to 3. However, these prior arts simply focus on the method of suppressing or reducing the generated bubbles, and have the drawback of requiring a huge investment in equipment to adjust the generation of bubbles. .

Among the existing non-defoaming soymilk manufacturing equipment, the closed system was installed with the aim of preventing overfilling, so ultimately the air bubbles in the soymilk were not sufficiently removed, and the air bubbles generated during the process interfered with the production of the soymilk. Soymilk cannot be boiled. On the other hand, in the method of separating the generated air bubbles, liquefying them in another container, and then re-injecting them into the boiled soymilk, the generated air bubbles separated before they were sufficiently heated and matured, so when the air bubbles were liquefied and re-introduced , there are problems such as non-uniformity of soy milk. In addition, in the existing non-defoaming agent method, when soymilk is boiled at a low temperature, the soymilk becomes undercooked due to the air bubbles in the equipment, and the heat denaturation is not sufficient, resulting in unreacted. is heated at a high temperature of
Therefore, there is a demand for a technology that is differentiated from existing soymilk production methods and that can stably produce well-cooked soymilk by a non-defoaming method.

Korean Patent Application No. 10-2005-0036613 (Title of the Invention: Defoamer-free tofu production equipment and tofu production method using decompression, condensation, degassing, and concentration technology) Korean Patent Application No. 10-2005-0036614 (Title of Invention: Degassing Device for Tofu Raw Material Liquid and Gas-Liquid Separator Usable therefor) Korean Patent Application No. 10-2009-0019554 (Title of the invention: Process for producing non-defoaming tofu using vacuum operation and gas-liquid separation technology)

Object 1 of the present invention is to heat ground soymilk or raw soymilk at an appropriate temperature without adding an antifoaming agent, while adjusting the pressure in the device to reduce or atmospheric pressure to break the generated bubbles and make a uniform product. To provide a method for producing soymilk, and to provide tofu rich in soymilk flavor because the produced soymilk has little offensive odor.

The object 2 of the present invention is to heat ground soymilk or raw soybean soup at an appropriate temperature without adding an antifoaming agent and adjust the pressure inside the device to atmospheric pressure and pressurized state to break the generated bubbles and homogenize the product. To provide a method for producing soybean milk, and to provide tofu rich in flavor using the soybean milk.

In order to achieve the above object 1, the present invention provides a soymilk comprising the step of repeatedly adjusting the pressure change in the kettle to a reduced pressure state and an atmospheric pressure state while heating the ground soymilk or the filtered soymilk after grinding in a boiling kettle. to provide a method of manufacturing

Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) reducing the pressure in the kettle and heating; and 3) repeatedly adjusting the pressure in the kettle to reduced pressure and atmospheric pressure,

Here, the pressure in the kettle is adjusted to atmospheric pressure when bubbles are generated in the ground soymilk or filtered soymilk after grinding, and is adjusted so that the soymilk is heated under reduced pressure when the bubbles are removed. To provide a method for producing soymilk.

In addition, the present invention provides a method for producing tofu, which includes the step of repeatedly adjusting the internal pressure of the boiler to a reduced pressure state and an atmospheric pressure state while heating the ground soymilk or the filtered soymilk after grinding in a boiling pot.

Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) reducing the pressure in the kettle and heating;
3) The pressure in the kettle is repeatedly adjusted to a reduced pressure and an atmospheric pressure. When air bubbles are generated in the ground soymilk or filtered soymilk after grinding, the pressure in the kettle is increased to atmospheric pressure, and when the air bubbles are removed. preparing soymilk by controlling heating under reduced pressure;
4) filtering the soymilk to separate or omit okara; and 5) adding a coagulant to the filtered soymilk or adding a coagulant to the filtered soymilk after cooling; provide a way.

The present invention also provides soymilk that is homogeneous, has little offensive odor, and has a rich soybean flavor, produced by the production method according to the present invention.
In addition, the present invention provides tofu that is produced by the production method according to the present invention and has little offensive odor and rich soybean flavor.

In order to achieve the above objective 2, the present invention includes a step of repeatedly adjusting the pressure change in the kettle to the atmospheric pressure and the pressurized state while heating the ground soymilk or the filtered soymilk after grinding in the boiling kettle. To provide a method for producing soymilk.

Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) bringing the kettle pressure to atmospheric pressure and heating the kettle;
3) repeatedly adjusting the kettle pressure to atmospheric and pressurized conditions;
here,

When air bubbles are generated in the ground soymilk or the filtered soymilk after grinding, the pressure inside the kettle is pressurized to remove the generated air bubbles, and when the air bubbles are removed, it is adjusted to the atmospheric pressure. To provide a method for producing soymilk, characterized by:

In addition, the present invention provides a method for producing tofu, which includes the step of repeatedly adjusting the internal pressure of the boiler to the atmospheric pressure and the pressurized state while heating the ground soymilk or the filtered soymilk after grinding in a boiler.

Specifically, the present invention includes the steps of: 1) charging ground soymilk or ground filtered soymilk into a boiling pot;
2) bringing the kettle pressure to atmospheric pressure and heating the kettle;
3) The pressure inside the kettle is repeatedly adjusted to the atmospheric pressure and the pressurized state, and the pressure inside the kettle is generated in the pressurized state when air bubbles are generated in the ground soymilk or the filtered soymilk after grinding under the atmospheric pressure. removing air bubbles, and adjusting the pressure to atmospheric pressure after the air bubbles are removed to produce soymilk;
4) filtering the soymilk to separate or omit okara; and 5) adding a coagulant to the obtained soymilk or adding a coagulant after cooling the obtained soymilk; to provide a method of manufacturing

The present invention also provides soymilk produced by the production method according to the present invention, which is homogeneous and rich in the unique flavor of soybeans.
In addition, the present invention provides tofu rich in soybean-specific flavor produced by the production method according to the present invention.

In the production of soymilk according to the present invention, homogeneous soymilk can be produced without adding an antifoaming agent. In particular, it is possible to produce antifoaming agent-free soymilk with excellent flavor even with a simple apparatus, unlike the conventional method that requires expensive and complicated machinery for the non-defoaming agent process.

In the present invention, air bubbles generated during the boiling process of soymilk are broken by adjusting the pressure, so that the soymilk can be ripened uniformly as a whole. In particular, there is a distinct difference in that the soybean protein can be thermally denatured at a lower temperature than in the existing soymilk production apparatus depending on the boiling pressure conditions.

1 is a schematic diagram of a soymilk manufacturing process according to the present invention. FIG. 1 is a schematic diagram of a soymilk manufacturing process according to the present invention. FIG. 1 is a schematic diagram of a tofu manufacturing process according to the present invention; FIG. 1 is a schematic view of a soymilk-producing pressure control device according to the present invention; FIG. 1 is a schematic view of a soymilk-producing pressure control device according to the present invention; FIG.

The present invention will be described in detail below.
The present invention provides a method for producing soymilk, which includes the step of repeatedly adjusting the pressure change in the kettle between reduced pressure and atmospheric pressure while heating ground soymilk or filtered soymilk after grinding in a boiling kettle.
Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) reducing the pressure in the kettle and heating; and 3) repeatedly adjusting the pressure in the kettle to reduced pressure and atmospheric pressure,

Here, the pressure in the kettle is adjusted so that when air bubbles are generated in the ground soy milk or filtered soy milk after grinding, the soy milk is brought to the atmospheric pressure, and when the air bubbles are removed, the soy milk is heated under reduced pressure. , to provide a method for producing soymilk.

In the manufacturing method,
In step 1), the ground soymilk can be prepared by soaking soybeans in water to soak them and then grinding them. Filtered soymilk after grinding can be produced by filtering ground soymilk.
The time for soaking the soybeans in water should be changed according to the air temperature, but it is preferably 5 to 8 hours in summer and 10 to 18 hours in winter.

It is preferable that soybeans and water are mixed at a weight ratio of 1:5.5 to 6.5 during the grinding. When the weight ratio is less than 1:5.5, the production yield is problematic, and when the weight ratio exceeds 1:6.5, the soymilk is not coagulated well due to its low concentration.
Any of a mortar, a mechanical pulverizer, or an electric pulverizer can be used for the grinding, and it is preferable to use a grinder.
A pump is preferably used to transfer the ground soymilk to the boiling pot, and the type of pump is not particularly limited.
Filtration for producing filtered soymilk after grinding can be performed by a conventional method such as filter paper, and is not particularly limited.

In step 2), a pressure reducing device can be used, and pressure is preferably reduced to -0.06 MPa to -0.005 MPa, more preferably -0.05 to -0.01 MPa. At this time, if the pressure is reduced too much, the temperature at which the soymilk boils will drop and the soymilk will not be thermally denatured, so it is important to observe the above conditions. Another reason is that when the lower limit of vacuum is lowered, a large-capacity vacuum pump is required to maintain the pressure while overcoming the amount of generated steam, and it is difficult to maintain the pressure (degree of vacuum).

The pressure reduction can be performed before heating, or can be performed simultaneously with heating. Heating is continued even in a decompressed state, and when the water starts to boil, the pressure increases due to steam generation. At this time, a vacuum pump can be used to maintain a constant pressure.

In step 2), the heating temperature of the soymilk is preferably 85 to 100°C, more preferably 89 to 98°C. is preferred. At this time, the lower limit of the temperature range is set to 85°C because it is the lowest temperature at which soybeans are thermally denatured. clotting reaction does not occur. In addition, setting the upper limit to 100°C means that a large-capacity vacuum pump is required to maintain the vacuum while overcoming the amount of steam generated during the process of boiling soymilk in a large volume, and the bubbles generated are controlled. This is because it is difficult to
Steam or an electric coil is preferably used as a heat source for the heating, but the type of heat source is not particularly limited.
In step 2), the heating time of soymilk is preferably 1 to 15 minutes, more preferably 3 to 10 minutes.

In step 3), the decompression and atmospheric pressure conditions are preferably repeatedly adjusted at least 3 times, more preferably at least 4 times. It is more preferable to carry out up to

In the repeated adjustment, when the soymilk begins to boil, air bubbles are generated to fill the inside of the kettle. In order to prevent this, it is preferable to bring the internal pressure of the kettle to atmospheric pressure when it reaches about 50 to 75% of the height of the kettle.

In addition, the present invention provides a method for producing tofu, which includes the step of repeatedly adjusting the internal pressure of the boiler to a reduced pressure state and an atmospheric pressure state while heating the ground soymilk or the filtered soymilk after grinding in a boiling pot.
Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) reducing the pressure in the kettle and heating the kettle;
3) The pressure inside the kettle is repeatedly adjusted to reduced pressure and atmospheric pressure. When bubbles are generated in the soymilk, the pressure inside the kettle is reduced to atmospheric pressure to remove the bubbles, and when the bubbles are removed, the pressure inside the kettle is reduced to reduced pressure. the step of producing soymilk by adjusting the
4) filtering the soymilk to separate or omit okara; and 5) adding a coagulant to the filtered soymilk or adding a coagulant to the filtered soymilk after cooling; provide a way.

Specifically, in the manufacturing method,
The manufacturing process of the ground soymilk or the filtered soymilk after grinding in step 1) is the same as the manufacturing method of the soymilk.

A decompression device can be used for decompression in step 2), and decompression is preferably from -0.06 MPa to -0.005 MPa, and more preferably from -0.05 to -0.01 MPa.
In step 2), the heating temperature of the soy milk is preferably 85 to 100° C., more preferably 89 to 98° C., and the soy milk liquid temperature is raised to 89° C. or higher for 10 seconds to 7 minutes, and the temperature is raised for 30 seconds to 4 minutes. preferably.
At this time, it is preferable to use steam or an electric coil as a heat source for heating, but the type of heat source is not particularly limited.
The heating time of soymilk in step 2) is preferably 1 to 15 minutes, more preferably 3 to 10 minutes.

In step 3), it is preferable to repeatedly adjust the decompression and atmospheric pressure conditions at least four times, and in particular, saponin components differ depending on the soybean variety, so it is more preferable to repeat until foaming does not occur.

Filtration in steps 1) and 4) may be performed by a conventional method such as filter paper, and is not particularly limited.

A coagulant is added in the step 5), and the amount of the coagulant for producing tofu is preferably 0.2 to 1.5% by weight per 1 L of soymilk.
The coagulant is preferably added when the soymilk is at 80°C or higher or when the cooled soymilk is at 15°C or lower.
After step 5), any one or more steps of compression, molding or packaging may be further performed.

It can be compressed for the texture, physical properties, packaging, etc. of tofu, can be molded for the marketability and packaging of tofu, can be injected and filled in packaging containers and storage containers, and can be used as necessary. Some or all of these processes may be omitted.
The present invention also provides soymilk that is homogeneous, has little offensive odor, and has a rich soybean flavor, produced by the production method according to the present invention.
In addition, the present invention provides tofu that is produced by the production method according to the present invention and has little offensive odor and rich soybean flavor.

In the present invention, air bubbles generated in the process of boiling soymilk are broken by adjusting the pressure to uniformly ripen the whole soymilk, and the soybean protein can be thermally denatured at a lower temperature than in the existing soymilk production equipment, resulting in offensive odors. It is possible to produce tofu that is rich in flavor with almost no tofu.
In addition, the present invention provides a pressure regulating heating apparatus for producing soymilk.
The pressure control heating device can have a configuration as shown in FIG.

The pressure control heating device includes a soymilk input container; a soymilk input and discharge port located at the bottom of the container; a steam heating unit connected to the bottom of the container; a vacuum pump located at the top of the container; and an atmospheric pressure control valve connected to the top of the vessel.

The decompression device releases the vacuum before the soymilk begins to boil and reaches the lower end of the vacuum pump connecting pipe at the top of the container to suppress the bumping phenomenon, and when the soymilk stops boiling, the pressure is reduced again to boil the soymilk. repeat.
EXAMPLES The present invention will now be described in detail with reference to examples and comparative examples.
However, the following examples and comparative examples merely illustrate the present invention, and the content of the present invention is not limited to the following examples and comparative examples.

<Examples 1 and 2, Comparative Examples 1 and 2> Production of soymilk by filtration method Specifically, the production of soymilk in <Example 1> was carried out as follows.

First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. Soybean milk was obtained by separating bean curd refuse from the ground soybean paste. The obtained soymilk was placed in a boiling pot capable of adjusting reduced pressure and atmospheric pressure, and the soymilk was heated at 92° C. while maintaining −0.02 MPa. An observation window was installed on the wall of the pot to observe the height of bubbles when they were generated. When bubbles were generated in the soymilk and the height of the bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to balance the pressure inside the kettle with the atmospheric pressure and remove the bubbles. When the air bubbles are removed, the pressure control valve is closed to bring the pressure in the kettle to -0.02 MPa. Thereafter, when air bubbles are generated again, the pressure control valve is operated to reduce the pressure to 0 MPa to remove the air bubbles. After repeating this process 5 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot soymilk.

Specifically, the production of soymilk in <Example 2> was carried out as follows.
First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot capable of adjusting reduced pressure and atmospheric pressure, and the raw soybean paste was heated at 92° C. while maintaining −0.02 MPa. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the raw soybean soup and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to balance the pressure inside the kettle with the atmospheric pressure and remove the air bubbles. When the air bubbles are removed, the pressure control valve is closed to bring the pressure in the kettle to -0.02 MPa again. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0 MPa, and the air bubbles are removed. After repeating this process 5 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot soybean paste, which was filtered to obtain soybean milk.

Specifically, the soymilk production of <Comparative Example 1> was carried out as follows.
First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot together with an antifoaming agent and heated at 92°C for 3 minutes. After obtaining the hot raw soybean paste, it was filtered to obtain soymilk.

Specifically, soymilk production of <Comparative Example 2> was performed as follows.
First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot together with an antifoaming agent and heated at 100° C. for 3 minutes. After obtaining the hot raw soybean paste, it was filtered to obtain soymilk.

A sensory test was conducted on <Examples 1 and 2> and <Comparative Examples 1 and 2>. Sensory tests of soymilk and tofu were quantified as shown in [Table 1] below for convenience. The soymilk sensory test item 'strange smell' means the smell of soymilk (green smell of beans), 'taste' means the taste of soymilk (sweet and soft taste), and the sensory test item of tofu is 'cohesiveness'. 'It is a test to check how well the soymilk is homogeneously produced by visually confirming the degree to which the tofu curd crumbles when the coagulant is mixed with the soymilk and crushed after coagulation. Flavor' is a test that subjectively judges the feeling, smell and taste of tofu received in the mouth.

As a result, it was confirmed that <Example 1> to <Example 2>, in which the reduced pressure state was maintained, removed much of the offensive odor (the grassy smell of soymilk) compared to the comparative examples. However, these examples did not smell undercooked like <Comparative Example 1>. In addition, it was found that there is no great difference in taste compared to <Comparative Example 2>, which is soymilk produced by a general antifoaming method.

<Examples 3 to 5, Comparative Examples 3 to 4> Production of tofu by pressure First, in order to produce tofu, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then washed for 5 to 8 hours in summer and for 5 to 8 hours in winter. was immersed in water for about 10 to 18 hours. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean soup was placed in a boiling pot capable of adjusting reduced pressure and atmospheric pressure, and -0.04 MPa (Example 3), -0.06 MPa (Example 4), and -0.08 MPa (Example 5) were added. Each soymilk was produced by heating the raw soybean soup at 92°C while maintaining the temperature. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the raw soybean soup and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to bring the pressure inside the kettle into equilibrium with the atmospheric pressure and remove the air bubbles. . When the bubbles are removed, the pressure control valve is closed, and the pressure inside the kettle is set to -0.04 MPa (Example 3), -0.06 MPa (Example 4), and -0.08 MPa (Example 4), respectively, like the initial pressure. 5). Thereafter, when air bubbles are generated again, the pressure control valve is operated to reduce the pressure to 0 MPa to remove the air bubbles. After repeating this process 5 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot soybean paste, which was filtered to obtain soybean milk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was injected into the molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

Specifically, tofu production in <Comparative Example 3> was carried out as follows.
First, in order to produce tofu, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot together with an antifoaming agent and heated at 92°C for 3 minutes. After obtaining the hot raw soybean paste, it was filtered to obtain soymilk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

Specifically, tofu production in <Comparative Example 4> was carried out as follows.
First, in order to produce tofu, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot together with an antifoaming agent and heated at 100° C. for 3 minutes. After obtaining the hot raw soybean paste, it was filtered to obtain soymilk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

As a result, in order to keep the pressure of the decompression pot low, a powerful vacuum pump is required for the amount of steam generated. Could not maintain pressure. In <Example 4>, the boiling temperature of the soymilk was relatively low, and the bubbles were not sufficiently removed compared to <Examples 2 and 3> or <Comparative Example 4>. It was confirmed from the coagulation time and sensory test that tofu of good quality could not be obtained in general. Also, when the soymilk was boiled at a low temperature as in <Comparative Example 3>, the antifoaming agent was added. In the case of <Examples 2 and 3>, it can be confirmed that the flavor was improved compared to <Comparative Example 4> produced by the existing antifoaming method.

<Examples 6 to 8> Production of tofu by removing air bubbles for 5 to 8 hours in summer and 10 to 10 hours in winter after washing the beans thoroughly after removing foreign substances with a sieve or the like to produce tofu. It was immersed in water for about 18 hours. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground soybean soybean paste was placed in a boiling pot capable of adjusting reduced pressure and atmospheric pressure, and heated at 92° C. while maintaining −0.02 MPa to produce soymilk. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the raw soybean soup and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to bring the pressure inside the kettle into equilibrium with the atmospheric pressure and remove the air bubbles. . When the air bubbles are removed, the pressure control valve is closed, and the pressure inside the kettle is again set to -0.02 MPa, like the initial pressure. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0 MPa, and the air bubbles are removed. After repeating this process once (Example 6), three times (Example 7), and seven times (Example 8), the pressure difference was removed by further heating for 10 seconds, and then the hot soybean paste was filtered to obtain soymilk. Obtained. In particular, in the case of <Example 8>, no bubbles were generated in the soymilk after adjusting the pressure five times, and the pressure was adjusted at arbitrary intervals. The soymilk thus obtained and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the tofu-shaped coagulant was crushed using a mechanism. After the crushed tofu was injected into the molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size to produce the tofu.

As a result, it was confirmed experimentally that in <Example 6> and <Example 7>, the soymilk protein was not sufficiently thermally denatured due to the short total heating time, and air bubbles were generated again after the pressure adjustment. did. In <Example 2> and <Example 8>, although it may differ depending on the apparatus, it can be confirmed that when bubbles are removed repeatedly while the soymilk is sufficiently boiled for a certain period of time, no more bubbles are generated.

<Examples 9-11> Production of tofu by heating temperature of soymilk First, in order to produce tofu, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then soaked for 5-8 hours in summer and 10-10 hours in winter. It was immersed in water for about 18 hours. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot capable of adjusting reduced pressure and atmospheric pressure, and while maintaining −0.02 MPa, the raw soybean paste was heated to 89° C. (Example 9), 95° C. (Example 10), and 98° C. (Example 10). Soymilk was produced by heating in Example 11). An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the raw soybean soup and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to balance the pressure inside the kettle with the atmospheric pressure and remove the air bubbles. When the air bubbles are removed, the pressure control valve is closed and the pressure in the pot is again set to -0.02 MPa, like the initial pressure. Thereafter, when air bubbles are generated again, the pressure control valve is operated to reduce the pressure to 0 MPa to remove the air bubbles. After repeating this process 5 times, the soybean milk was obtained by further heating for 10 seconds to remove the pressure difference and then filtering the hot soybean paste. The soymilk thus obtained and the coagulant (emulsified coagulant) were appropriately agitated so as to be uniformly mixed, and then the tofu-shaped coagulant was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

As a result, it is judged that when the boiling temperature of soymilk is lower than 89°C, the texture and flavor of the produced tofu are greatly deteriorated. Even if the boiling temperature is higher than 98 ° C., it is judged that there is no big difference in the sensory test of tofu, but in the mass production process, the generated steam pressure is remarkably high, and the pressure is stabilized. considered difficult to maintain.

In addition, the present invention provides a method for producing soymilk, which includes the step of repeatedly adjusting the internal pressure of the soybean milk to the atmospheric pressure and the pressurized state while heating the ground soymilk or the filtered soymilk after grinding in a boiling pot.
Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) bringing the kettle pressure to atmospheric pressure and heating the kettle;
3) repeatedly adjusting the kettle pressure to atmospheric and pressurized conditions;
here,

When air bubbles are generated in the ground soymilk or the filtered soymilk after grinding, the pressure inside the kettle is pressurized to remove the generated air bubbles, and when the air bubbles are removed, it is adjusted to the atmospheric pressure. To provide a method for producing soymilk, characterized by:

In the manufacturing method,
In step 1), the ground soymilk can be prepared by soaking soybeans in water to soften them and then grinding them. Filtered soymilk after grinding can be produced by filtering ground soymilk.
The time for soaking the soybeans in water should be changed according to the air temperature, but it is preferably 5 to 8 hours in summer and 10 to 18 hours in winter.

It is preferable that soybeans and water are mixed at a weight ratio of 1:5.5 to 6.5 during the grinding. When the weight ratio is less than 1:5.5, the production yield is degraded, and when the weight ratio exceeds 1:6.5, the concentration of soymilk becomes low and coagulation does not occur well.
Any of a mortar, a mechanical pulverizer, or an electric pulverizer can be used for the grinding, and it is preferable to use a grinder.
A pump is preferably used to transfer the ground soymilk to the boiling pot, and the type of pump is not particularly limited.
Filtration for producing filtered soymilk after grinding can be performed by a conventional method such as filter paper, and is not particularly limited.

In step 2), a device such as an air compressor can be used for pressurization, and the pressure is preferably 0.105 MPa to 0.3 MPa, more preferably 0.11 to 0.2 MPa. This is because if the lower limit is lowered, there is no difference from the generated steam pressure, so there is no effect of removing air bubbles, and if the pressure is too high, there is a risk that the soymilk in the boiling pot will blow out.

In the case of pressurizing, if bubbles are generated during boiling at atmospheric pressure, the valve is closed and sealed, and a pressure slightly higher than the tank internal pressure is injected using an air compressor or the like to remove bubbles. is removed, the pressurization can be discontinued and the valve can be opened to bring the internal tank pressure to atmospheric pressure.

In step 2), the heating temperature of the soymilk is preferably 85 to 110°C, more preferably 89 to 105°C, and the soymilk is heated to 89°C or higher for 10 seconds to 7 minutes, but preferably 30 seconds to 4 minutes. is preferred. The reason why the lower limit of the above temperature range is 85°C is because it is the lowest temperature at which soybeans are thermally denatured. does not occur. The reason why the upper limit is set to 110° C. is that when the soymilk is boiled at a high temperature, secondary heat denaturation may occur and the soymilk may not be solidified. Also, if the pressure applied to remove the air bubbles is too high, the soymilk will spurt out during the process of removing the pressure to return the pressure in the boiling pot to the atmospheric pressure after removing the air bubbles, which poses a safety hazard. .
At this time, it is preferable to use steam or an electric coil as a heat source for heating, and the type of heat source is not particularly limited.
The heating time of the soymilk in step 2) is preferably 1 to 15 minutes, more preferably 3 to 10 minutes.

In step 3), the decompression and atmospheric pressure conditions are preferably repeatedly adjusted at least 6 times, and in particular, saponin components vary depending on the soybean variety, so it is more preferable to repeat until foaming does not occur. The reason why the number of repetitions is different from that under reduced pressure is that the temperature of the soymilk is high, so that the production of saponin increases relatively rapidly.

In addition, the present invention provides a method for producing tofu, which includes the step of repeatedly adjusting the internal pressure of the boiler to the atmospheric pressure and the pressurized state while heating the ground soymilk or the filtered soymilk after grinding in a boiler.

Specifically, the present invention provides
1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) bringing the kettle pressure to atmospheric pressure and heating the kettle;
3) The pressure inside the kettle is repeatedly adjusted to the atmospheric pressure and the pressurized state, and the pressure inside the kettle is generated in the pressurized state when air bubbles are generated in the ground soymilk or the filtered soymilk after grinding under the atmospheric pressure. removing air bubbles, and adjusting the pressure to atmospheric pressure after the air bubbles are removed to produce soymilk;
4) filtering the soymilk to separate or omit okara; and 5) adding a coagulant to the obtained soymilk or adding a coagulant after cooling the obtained soymilk; to provide a method of manufacturing

Specifically, in the manufacturing method,
The manufacturing process of the ground soymilk and the filtered soymilk after grinding in the step 1) is the same as the manufacturing method of the soymilk.

In step 2), a device such as an air compressor can be used for pressurization, and the pressure is preferably 0.05 MPa to 0.3 MPa, more preferably 0.1 to 0.2 MPa.
In step 2), the heating temperature of the soymilk is preferably 85 to 110°C, more preferably 89 to 105°C, and the soymilk is heated to 89°C or higher for 10 seconds to 7 minutes, but preferably 30 seconds to 4 minutes. is preferred.
At this time, it is preferable to use steam or an electric coil as a heat source for heating, and the type of heat source is not particularly limited.
The heating time of the soymilk in step 2) is preferably 1 to 15 minutes, more preferably 3 to 10 minutes.

In step 3), it is preferable to repeatedly adjust the decompression and atmospheric pressure conditions at least 6 times. Particularly, saponin components differ depending on soybean varieties.

Filtration in steps 1) and 4) may be performed by a conventional method such as filter paper, and is not particularly limited.

A coagulant is added in the step 5), and the amount of the coagulant for producing tofu is preferably 0.2 to 1.5% by weight per 1 L of soymilk.
The coagulant is preferably added when the soymilk is at 80°C or higher or when the cooled soymilk is at 15°C or lower.
After step 5), any one or more steps of compression, molding or packaging may be further performed.

It can be compressed for the texture, physical properties, packaging, etc. of tofu, can be molded for the marketability and packaging of tofu, can be injected and filled in packaging containers and storage containers, and can be used as necessary. Some or all of these processes may be omitted.

The present invention also provides a soymilk produced by the production method according to the present invention, which is homogeneous and has a rich flavor unique to soybeans. To provide tofu rich in soybean-specific flavor.
According to the present invention, air bubbles generated in the process of boiling soymilk can be broken by adjusting the pressure, and the whole soymilk can be ripened uniformly to produce flavorful tofu.

In addition, the present invention provides a pressure regulating heating apparatus for producing soymilk.
The pressure control heating device can have a configuration as shown in FIG.
The pressure control heating device includes a soymilk input container; a soymilk input and discharge port located at the bottom of the container; a steam heating unit connected to the bottom of the container; an air compressor located at the top of the container; and an atmospheric pressure control valve connected to the top of the vessel.

When the soymilk begins to boil under atmospheric pressure, the pressure control heating device uses the valve at the top of the container to apply the air pressure of the pressurizing air compressor to suppress the bumping phenomenon. Repeat boiling the soy milk.

EXAMPLES The present invention will now be described in detail with reference to examples and comparative examples.
However, the following examples and comparative examples merely illustrate the present invention, and the content of the present invention is not limited to the following examples and comparative examples.

<Examples 12 and 13> Production of soymilk by filtration method Specifically, the production of soymilk in <Example 12> was performed as follows.
First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. Soybean milk was obtained by separating bean curd refuse from the ground soybean paste. The soymilk thus obtained was placed in a boiling pot capable of adjusting atmospheric pressure and pressure, and the soymilk was heated at 98° C. under atmospheric pressure. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the soymilk and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the upper end of the kettle was operated to apply pressure to the inside of the kettle to 0.15 MPa to remove the air bubbles. When the air bubbles are removed, the pressure control valve is opened to return the pressure inside the kettle to the atmospheric pressure. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0.15 MPa, and the air bubbles are removed. After repeating this process 6 times, the mixture was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure was removed to obtain hot soymilk.

Specifically, the production of soymilk in <Example 13> was carried out as follows.
First, in order to produce soymilk, beans were thoroughly washed after removing foreign matter with a sieve or the like, and then soaked in water for 5 to 8 hours in summer and 10 to 18 hours in winter. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot capable of adjusting atmospheric pressure and pressure, and soymilk was heated at 98° C. under atmospheric pressure. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the soymilk and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the upper end of the kettle was operated to apply pressure to the inside of the kettle to 0.15 MPa to remove the air bubbles. After the air bubbles are removed, the pressure control valve is opened to restore the pressure in the kettle to the atmospheric pressure. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0.15 MPa, and the air bubbles are removed. After repeating this process 6 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot raw soybean paste, which was filtered to obtain soybean milk.
A sensory test was performed on <Examples 12 and 13> and <Comparative Example 2>. Sensory tests of soymilk and tofu were quantified as shown in [Table 6] below for convenience.

As a result, <Example 12> and <Example 13> using a pressurization method were boiled without an antifoaming agent, and <Comparative Example 2>, which is soymilk produced by a general antifoaming method, was found. It turned out that there was no big difference in taste even when compared.

<Examples 14 to 17> Production of tofu by pressure First, in order to produce tofu, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then soaked for 5 to 8 hours in summer and 10 to 18 hours in winter. immersed in water to some extent. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean soup was put into a boiling pot capable of controlling atmospheric pressure and pressure, and the raw soybean soup was heated at 92° C. to produce each soymilk. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the soybean soup and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the top of the kettle was operated to apply pressure to the inside of the kettle, and each pressure was 0.1 MPa (Example 14). , 0.15 MPa (Example 15), 0.25 MPa (Example 16), and 0.3 MPa (Example 17) to remove air bubbles. After the air bubbles are removed, the pressure control valve is opened to restore the pressure in the kettle to the atmospheric pressure. After that, when air bubbles were generated again, the pressure control valves were operated again to 0.1 MPa, 0.15 MPa, 0.25 MPa, and 0.3 MPa, respectively, to remove the air bubbles. After repeating this process 6 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot raw soybean paste, which was filtered to obtain soybean milk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

As a result, in the cases of <Example 14> to <Example 16>, there was no significant difference compared to <Comparative Example 4> in which an antifoaming agent was used. However, when the applied pressure is high as in <Example 17>, although the generated air bubbles can be removed, the soymilk inside is spurted out at the moment the pressure is removed. In order to control this, decompression equipment was necessary, and the experiment could not proceed any further. However, it is judged that the non-defoaming method can be sufficiently applied even when there is a depressurization facility.

<Examples 18-20> Production of tofu by removing air bubbles for 5 to 8 hours in summer and 10 to 10 hours in winter after removing foreign matter from beans with a sieve or the like to produce soy milk. It was immersed in water for about 18 hours. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot capable of adjusting atmospheric pressure and pressure, and soymilk was heated at 98° C. under atmospheric pressure. An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the soymilk and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the upper end of the kettle was operated to apply pressure to the inside of the kettle to 0.15 MPa to remove the air bubbles. After the air bubbles are removed, the pressure control valve is opened to restore the pressure in the kettle to the atmospheric pressure. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0.15 MPa, and the air bubbles are removed. After repeating this process 3 times (Example 18), 4 times (Example 19), and 5 times (Example 20), the pressure difference was removed by further heating for 10 seconds to obtain hot raw soybean paste, which was filtered. I got soy milk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

As a result, since the total heating time was short in <Examples 18> to <Examples 20>, not only was the soymilk protein not sufficiently denatured by heat, but also bubbles were generated again after adjusting the pressure. confirmed. Although it may differ depending on the device, it can be confirmed that no more air bubbles are generated when the soy milk is boiled sufficiently for a certain period of time and air bubbles are removed repeatedly.

<Examples 21 to 24> Production of tofu by soymilk heating temperature First, in order to produce soymilk, beans were washed thoroughly after removing foreign matter with a sieve or the like, and then soaked for 5 to 8 hours in summer and 10 to 10 hours in winter. It was immersed in water for about 18 hours. After that, water was added to the soaked beans and ground using a grinder. At this time, the amount of water added was 36 kg, which is about 6 times as much as 6 kg of raw beans. The ground raw soybean paste was placed in a boiling pot capable of adjusting atmospheric pressure and pressure, and the soybean milk was heated to 90° C. (Example 21), 94° C. (Example 22), and 102° C. (Example 23) under atmospheric pressure. , 106° C. (Example 24). An observation window was installed on the wall of the cauldron to observe the height of bubbles when they were generated. When air bubbles were generated in the soymilk and the height of the air bubbles filled about 2/3 of the inside of the kettle, the pressure control valve at the upper end of the kettle was operated to apply pressure to the inside of the kettle to 0.15 MPa to remove the air bubbles. After the air bubbles are removed, the pressure control valve is opened to restore the pressure in the kettle to the atmospheric pressure. After that, when air bubbles are generated again, the pressure control valve is operated to set the pressure to 0.15 MPa, and the air bubbles are removed. After repeating this process 6 times, it was further heated for 10 seconds to confirm that no more bubbles were generated, and the pressure difference was removed to obtain hot raw soybean paste, which was filtered to obtain soybean milk. The obtained soymilk and the coagulant (emulsified coagulant) were appropriately stirred so as to be uniformly mixed, and then the coagulated tofu was crushed using a mechanism. After the crushed tofu was poured into a molding box and pressed, the pressed tofu was taken out from the molding box and cut into a predetermined size.

As a result, when the soymilk boiling temperature is lower than 90°C, it is judged that the texture and flavor of the produced tofu are significantly deteriorated. Even if the boiling temperature is higher than 106 ° C., there will be no significant difference in the sensory properties of the tofu in the sensory test, but the generated steam pressure will be significantly higher. pressure must be applied. Also, when the boiling temperature was 90° C., bubbles were removed 6 times, but there was a phenomenon that bubbles were further generated.

Claims (6)

1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) reducing the pressure in the kettle and heating to simmer the ground soymilk or the filtered soymilk ;
In step 2), repeatedly adjusting the pressure in the kettle to a reduced pressure state and an atmospheric pressure state;
In the iterative regulation,
When air bubbles are generated more than 2/3 of the height of the kettle, open the pressure control valve at the top of the kettle to bring the pressure inside the kettle to atmospheric pressure and remove the air bubbles,
The pressure reduction is to reduce the pressure to a pressure of -0.06 MPa to -0.005 MPa,
A method for producing soymilk, wherein the step of repeatedly adjusting the reduced pressure and the atmospheric pressure is performed at least five times, and bubbles are not generated any more. The method for producing soymilk according to claim 1, wherein the heating condition in step 2) is heating at a temperature of 85°C to 100°C for 1 minute to 15 minutes. producing soymilk by the method of claim 1;
A method for producing tofu, comprising: producing tofu using the produced soymilk. 1) Putting ground soymilk or filtered soymilk after grinding into a boiling pot;
2) heating the kettle to boil the ground soy milk or the filtered soy milk ;
In step 2), repeatedly adjusting the pressure in the kettle to atmospheric pressure and pressurized state;
In the iterative regulation,
When air bubbles are generated more than 2/3 of the height of the pot, the pressure control valve at the upper end of the pot is closed and pressurized. adjusting the pressure to atmospheric pressure and heating,
The pressurization is to pressurize to a pressure of 0.05 MPa to 0.3 MPa,
A method for producing soymilk, wherein the step of repeatedly adjusting the pressure to the atmospheric pressure and the pressurized state is performed at least six times, and air bubbles are not generated any more. The method for producing soymilk according to claim 4, wherein the heating condition in step 2) is heating at a temperature of 89°C to 105°C for 1 minute to 15 minutes. producing soymilk by the method of claim 4;
A method for producing tofu, comprising: producing tofu using the produced soymilk.

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