JP6008888B2 - Heating cooker and heating control method - Google Patents

Description

  The present invention relates to a heating cooker and a heating control method for cooking a pan-like container containing food such as rice.

  Although brown rice food has been reviewed for a long time due to health-consciousness, brown rice has skin (seed coat and pericarp), so it is not preferred in terms of “cooking time is long” and “the skin is not so tasty because it is not smooth” There are many cases.

  Therefore, conventionally, for the purpose of cooking rice in a short time and cooking to the same texture as white rice rice, there is a rice cooking process that includes a pre-cooking process that absorbs water into brown rice and a heating process that promotes gelatinization of brown rice And the rice cooker which provides the process of adding water in the said heating process and cooks rice is proposed (for example, refer patent document 1).

Japanese Patent Laying-Open No. 2011-206364 (see, for example, claim 1)

  However, as described in Patent Document 1, when water is added while boiling in the heating process, the brown rice skin is broken and at the same time the rice grains are cracked so that the starch in the endosperm portion inside the brown rice is the rice cooking liquid When the food is cooked and cooked, the skin and the endosperm part are separated, and there is a problem that the taste of the skin is bad and it is not delicious.

  This invention is made | formed in order to solve the above subjects, and it aims at providing the heating cooker and the heating control method which can cook delicious brown rice rice in a short time.

A heating cooker according to the present invention includes heating means for heating a pot-shaped container that accommodates an object to be heated, and control means for controlling the heating means, wherein the control means is provided on the pot-shaped container. In the water absorption process that is performed in the rice cooking process for brown rice that contains brown rice as a heated object and cooks the brown rice, when the temperature of the heated object reaches or exceeds the softening temperature of the brown rice skin, the heating means The input is stopped , and then the temperature of the object to be heated is maintained at the gelatinization temperature or higher .

The heating control method according to the present invention is a heating control method including a rice cooking process for brown rice that cooks brown rice, and in the water absorption process performed in the rice cooking process, the heating object contained in the pot-shaped container When the temperature reaches or exceeds the softening temperature of the brown rice skin, the input to the heating means for heating the pan-like container is stopped, and after the input to the heating means is stopped, the temperature of the object to be heated is a predetermined set temperature. When the temperature is further lowered, the temperature of the heated object is maintained at a predetermined gelatinization temperature or higher based on temperature information of any one of the temperature of the pan-shaped container and the temperature of the heated object .

  According to the heating cooker and the heating control method of the present invention, brown rice can be cooked in a short time and the cooked rice becomes delicious by softening the brown rice skin and performing the water absorption process. .

It is a cross-sectional schematic diagram which shows roughly an example of a structure of the household IH type rice cooker which concerns on embodiment of this invention. It is a figure which shows an example of transition of the rice cooking process of the domestic | home-use IH type rice cooker which concerns on embodiment of this invention, and to-be-heated material temperature, pan-shaped container temperature, and the electricity supply to a heating coil. It is a flowchart explaining the rice cooking process of the household IH type rice cooker which concerns on embodiment of this invention. It is an image figure which shows the state of the brown rice immediately after completion | finish of the water absorption process heated with the temperature history different from this Embodiment. It is an image figure which shows the state of the brown rice immediately after completion | finish of the water absorption process of the domestic | home-use IH type rice cooker which concerns on embodiment of this invention. It is a figure which shows another example of the rice cooking process of the domestic | home-use IH type rice cooker which concerns on embodiment of this invention, and the transition of the to-be-heated material temperature, pan-shaped container temperature, and the electric power supplied to a heating coil.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a heating cooker and a heating control method according to the present invention will be described with reference to the drawings, taking as an example a case where the heating cooker and a heating control method are applied to a domestic IH rice cooker. The present invention is not limited to the embodiments described below. Moreover, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one. Further, in the following description, terms for indicating directions (for example, “up”, “down”, “right”, “left”, “front”, “back”, etc.) are used as appropriate for easy understanding. This is for explanation and these terms do not limit the present invention.

  FIG. 1 is a schematic cross-sectional view schematically showing an example of the configuration of a domestic IH rice cooker (hereinafter referred to as a rice cooker 100) according to an embodiment of the present invention. Based on FIG. 1, the rice cooker 100 is demonstrated. The rice cooker 100 cooks the heated object by heating the pot-shaped container 5 containing the heated object (rice 200 and water 201 in the present embodiment) with the heating coil 3.

  As shown in FIG. 1, the rice cooker 100 includes, for example, a bottomed cylindrical main body 1 and a lid 10 that is attached to the main body 1 and opens and closes the upper opening of the main body 1.

(Main unit 1)
The main body 1 drives the container cover 2, the heating coil 3 as a heating means, the pan bottom temperature sensor 4, the hinge part 6 that supports the lid 10 so that it can be opened and closed, the time measuring means 7, each part and each device. The control means 8 which controls and performs a rice cooking process is provided.

The container cover 2 is formed in a bottomed cylindrical shape, and the pot-shaped container 5 is detachably accommodated therein. In the center of the bottom of the container cover 2, a hole 2a into which the pan bottom temperature sensor 4 is inserted is provided.
The pot-like container 5 is made of a material containing a magnetic metal that generates heat by induction heating, and has a bottomed cylindrical shape. A flange portion 5 a is formed on the outer periphery of the upper end portion of the pot-like container 5.

  The heating coil 3 is energized and controlled by the control means 8 and induction-heats the pan-like container 5. As a heating means, an electric heater such as a sheathed heater may be provided in place of the heating coil 3. Moreover, in the example of FIG. 1, although the heating coil 3 is arrange | positioned near the bottom face of the pan-like container 5, arrangement | positioning of the heating coil 3 is not limited to the thing of illustration, For example, in addition to the bottom face vicinity of the pan-like container 5 The heating coil 3 may be provided along the side surface of the pan-like container 5. The heating coil 3 corresponds to the “heating means” of the present invention.

  The pan bottom temperature sensor 4 is composed of, for example, a thermistor, and detects the temperature of the pan-like container 5. The pan bottom temperature sensor 4 is biased upward by an elastic means such as a spring and is configured to come into contact with the bottom surface of the pan-like container 5 accommodated in the container cover 2. Information regarding the temperature of the pot-like container 5 detected by the pot bottom temperature sensor 4 is output to the control means 8. The specific configuration of the pan bottom temperature sensor 4 is not limited to the thermistor, and the temperature of the pan-shaped container 5 such as an infrared sensor is not contacted in addition to the contact-type temperature sensor that detects the temperature by contacting the pan-shaped container 5. You may employ | adopt the non-contact-type temperature sensor detected by.

The hinge portion 6 is provided on one end side (left side of the drawing) of the upper portion of the main body 1 and supports the lid body 10 so as to be opened and closed.
In addition, you may provide the main body 1 with the handle (illustration omitted) for conveying the rice cooker 100. FIG. When the handle is provided, the handle may be pivotally supported substantially at the front and rear center of the upper part of the side surface of the main body 1 so that the rotation direction of the handle coincides with the rotation direction of the lid body 10. Then, when transporting the rice cooker 100, the user can lift the handle by rotating the handle so that it is positioned almost directly above the pivot point of the handle, and can transport the rice cooker 100 with only the handle. It becomes.

  The time measuring means 7 is instructed by the control means 8 and counts the elapsed time. Then, the elapsed time counted by the time measuring means 7 is output to the control means 8.

  The control means 8 controls the high-frequency current supplied to the heating coil 3 based on the output from the pan bottom temperature sensor 4 and the operation display unit 15 and the internal temperature sensor 16 provided on the lid 10. In addition, the control means 8 controls the overall operation of the rice cooker 100. The control means 8 can be configured by hardware such as a circuit device that realizes the function, or can be configured by an arithmetic device such as a microcomputer or a CPU and software executed thereon.

(Cover 10)
The lid 10 has an outer lid 11 and an inner lid 12. A cartridge 14 described later is detachably provided on the outer lid 11, and an operation display unit 15 is provided on the upper surface of the outer lid 11.

The outer lid 11 constitutes an upper portion and a side portion of the lid body 10, and an inner lid 12 is detachably attached to a lower surface (a surface facing the pan-like container 5).
The inner lid 12 is made of, for example, a metal such as stainless steel, and is attached to the surface of the outer lid 11 on the main body 1 side via a locking member 13. On the peripheral edge of the inner lid 12 is attached a lid packing 9 of a sealing material for ensuring hermeticity with the flange portion 5 a formed on the outer periphery of the upper end portion of the pan-like container 5. Further, the inner lid 12 is provided with a hole 12a into which the internal temperature sensor 16 is inserted. Further, the inner lid 12 is provided with a steam port 12b through which steam generated in the pan-like container 5 enters and exits, and communicates with a steam inlet 14a of the cartridge 14 described later.
Note that a packing 11 a is attached to the outer lid 11 to close a gap on the outer periphery of the internal temperature sensor 16 inserted into the hole 12 a of the inner lid 12.

(Cartridge 14)
The cartridge 14 is detachably provided on the upper surface of the outer lid 11. The cartridge 14 includes a steam inlet 14a having a valve (not shown) that moves up and down according to the steam pressure generated during rice cooking, and a steam exhaust that discharges the steam that has passed through the valve of the steam inlet 14a to the outside. An outlet 14b is provided. The steam inlet 14a communicates with the steam port 12b, and the steam passes through the steam port 12b, enters the cartridge 14 through the steam inlet 14a, flows through the cartridge 14, and exits the cartridge 14 from the steam outlet 14b. leak. Since the steam is cooled and condensed in the process of flowing through the cartridge 14, the amount of steam flowing out of the rice cooker 100 can be reduced.

(Operation display unit 15)
The operation display unit 15 is provided on the upper surface of the outer lid 11. The operation display unit 15 accepts various instructions from the user (for example, start, cancellation, reservation, etc. of rice cooking) and displays various information (for example, information related to operation input, operation status of the rice cooker 100, etc.). To do. Items that can be set for the operation display unit 15 include, for example, start and cancellation of rice cooking, rice cooking reservation, and rice cooking menu. Specific examples of the rice cooking menu include things related to rice types such as white rice cooking or brown rice cooking, things related to cooking time such as standard rice cooking or quick cooking rice, things related to the hardness of cooked rice such as cracks or soft rice Is mentioned. Items displayed by the operation display unit 15 include, for example, the state of the rice cooker 100 during cooking or reservation standby, the contents of the set rice cooking menu, the scheduled cooking time, the current time, the amount of rice to be cooked, etc. Is mentioned. The specific configuration of the operation display unit 15 shown here is merely an example, and does not limit the present invention.

  When the user performs an operation input to the operation display unit 15, the control means 8 built in the main body 1 operates the heating coil 3 according to the input rice cooking menu and the rice cooking program according to the amount of rice to be cooked. Let the rice cooking process run.

(Internal temperature sensor 16)
The internal temperature sensor 16 is temperature detection means for detecting the temperature in the pan-like container 5 and is attached to the outer lid 11. A part of the internal temperature sensor 16 is inserted into the hole 12a of the inner lid 12, and the internal temperature sensor 16 detects the temperature in the pan-like container 5 through the hole 12a. The internal temperature sensor 16 can be composed of, for example, a thermistor. Information regarding the temperature in the pan-like container 5 detected by the internal temperature sensor 16 is output to the control means 8.

Next, operation | movement of the rice cooking process of the rice cooker 100 is demonstrated.
FIG. 2 is a diagram illustrating an example of the rice cooking process of the rice cooker 100 and the transition of the heated object temperature, the pan-like container temperature, and the electric power supplied to the heating coil. FIG. 3 is a flowchart for explaining the rice cooking process of the rice cooker 100. Hereinafter, the rice cooking process of the rice cooker 100 is demonstrated with reference to FIG.2 and FIG.3. In the present embodiment, the temperature of the object to be heated, that is, the internal temperature of the pan-like container 5 is detected based on the detection value of the internal temperature sensor 16. Further, the pot-like container temperature (the temperature of the pot-like container 5) is detected based on the detection value of the pot bottom temperature sensor 4.

First, each process which comprises the rice cooking process of the rice cooker 100 is demonstrated roughly.
As shown in FIGS. 2 and 3, the rice cooking process of the rice cooker 100 includes a water absorption process (step S1), a temperature raising process (step S7), a boiling maintenance process (step S8), and a steaming process (step S9). Including.

  The water absorption process is a process of promoting water absorption even inside the rice. The next temperature raising step is a step from the end of the water absorption step until the water in the pot-like container 5 boils. If the water in the pan-like container 5 boils, the control means 8 will transfer to the next boiling maintenance process. In this boiling maintenance process, it heats so that the temperature in the pan-like container 5 may maintain a boiling temperature, and gelatinizes starch of rice. The last steaming process is a process in which gelatinization proceeds to the center of the rice grain by steaming the rice in the pan-like container 5 and the moisture distribution in the rice grain is made uniform.

Next, operation | movement of the rice cooking process of the rice cooker 100 is demonstrated.
First, the user stores the pot-like container 5 containing rice 200 and water 201 in the container cover 2 in the main body 1, closes the lid 10, and sets the rice cooking menu as brown rice rice cooking with the operation display unit 15. Then, a rice cooker switch (not shown) is pressed to give an operation instruction to the rice cooker 100. As for the rice cooker 100, the control means 8 starts a rice cooking process because the rice cooking switch is pushed down by the user and an operation instruction is given.

  When heating is started, the water absorption step of Step S1 is performed. The control means 8 causes the time measuring means 7 to start measuring the elapsed time t (step S2), energizes the heating coil 3 with a preset power P, and heats the pan-like container 5 (step S3).

  Next, the control means 8 determines whether or not the temperature T of the object to be heated detected by the internal temperature sensor 16 is equal to or higher than T2 (for example, 80 ° C.) which is the softening temperature of the brown rice skin (step S4). . When it is determined that the temperature T detected by the internal temperature sensor 16 is equal to or higher than T2 (step S4; Yes), the control unit 8 cuts off the power supply to the heating coil 3 (step S5). Then, the control means 8 determines whether or not the elapsed time t counted by the time measuring means 7 is equal to or longer than a preset elapsed time t2 (step S6). When it is determined that the elapsed time t is equal to or longer than the preset elapsed time t2 (step S6; Yes), the control means 8 proceeds to the next temperature raising process, and sequentially performs the boiling maintenance process and the steaming process, and the rice cooking is performed. finish.

  As described above, according to the rice cooker 100, when the object to be heated reaches a temperature at which the skin softens, the energization to the heating coil 3 is interrupted and the temperature of the object to be heated is lowered, so that it is delicious in a short time. There is an effect that rice can be cooked.

  FIG. 4 is an image diagram showing the state of brown rice immediately after completion of the water absorption process heated with a temperature history different from that of the present embodiment. FIG. 5 is an image diagram showing the state of brown rice immediately after the water absorption process of the rice cooker 100 is completed. The cooked state of brown rice will be described with reference to FIGS. 4 and 5.

  In the water absorption step, even if the temperature of the article to be heated is kept at a low temperature (for example, 30 ° C.), the brown rice skin does not become soft and water absorption into the starch inside does not proceed. To absorb water at a low temperature, it takes more than one night. Even if the temperature rising process, boiling maintaining process, steaming process and rice cooking process are carried out with insufficient water absorption, the skin and the endosperm part do not become soft. If the amount of water is increased and kept boiling for a long time, only the endosperm part absorbs water excessively and becomes messed up.

  Therefore, in the rice cooker 100, the brown rice skin is softened by exposing the brown rice to a high temperature in the water absorption step and the water absorption of the starch also proceeds, so that the rice can be cooked deliciously in a short time. Experiments have shown that the brown rice skin begins to soften from around 70 ° C., and that the higher the temperature, the easier the softening proceeds, especially at 80 ° C. or higher. Furthermore, the heating is not simply continued so as to maintain the softening temperature, but if the temperature reaches or exceeds the softening temperature of the skin as in this embodiment, the input to the heating means is stopped and the temperature of the object to be heated is lowered. It was found that the rice was cooked in a state where the shape of the grains was kept clean, resulting in a delicious brown rice with a favorable texture.

  If heating is continued with the softening temperature of the skin, the starch in the endosperm part rapidly and excessively swells from the tears generated in the skin, and as a result, a part of the starch protrudes from the tears, At the end of the water absorption process, the rice grains have an irregular shape (see FIG. 4). When cooked in this state, the starch portion that protrudes from the skin is messed up and the texture is poor, so it is not delicious.

  However, when the softening temperature is reached as in this embodiment, the input to the heating means is stopped, and the excessive water absorption of starch in the endosperm portion can be suppressed by lowering the temperature of the heated object. Then, once exposed to a high temperature equal to or higher than the softening temperature, the skin softens and the tissue structure loosens, and the water absorption of the starch in the endosperm portion gradually proceeds due to residual heat, so that the skin and the endosperm portion swell almost simultaneously. Therefore, the water absorption process can be completed while maintaining the shape of the rice grains as shown in FIG. 5, and when cooked in this state, the rice grain has a good texture and becomes a delicious brown rice rice.

In step S4, the temperature of the object to be heated is detected by the internal temperature sensor 16 to determine whether the heating coil 3 is energized or cut off, but by detecting the pot bottom temperature T1 by the pot bottom temperature sensor 4, the temperature of the object to be heated is determined. You may make it judge by predicting temperature. By detecting the pan bottom temperature T <b> 1 with the pan bottom temperature sensor 4, it is possible to prevent brown rice at the bottom of the pan from being overheated and being burnt.
However, it is possible to determine that the entire object to be heated has sufficiently reached the softening temperature of the skin by estimating and determining the temperature of the object to be heated by the internal temperature sensor 16.
Further, instead of based on the information of the temperature detection means, heating may be performed for a preset time t1 with a preset power P.

  When the outside air temperature is high or the amount of cooked rice is large, the temperature may not easily decrease even if the power supply to the heating coil 3 is cut off. In that case, as described above, the starch in the endosperm part rapidly and excessively absorbs water and swells, leading to unsavory brown rice. Therefore, you may make it provide a water supply means in the rice cooker 100 as a cooling means (not shown). For example, if it is determined in step S4 that the temperature T detected by the internal temperature sensor 16 is equal to or higher than T2 (step S4; Yes), the control means 8 operates the water supply means to supply water into the pan-like container 5 and cover it. Reduce the temperature of the heated object. Further, a fan may be provided as a cooling means, and cooling may be performed by applying air with the fan.

  Conversely, when the outside air temperature is low or the amount of cooked rice is small, the temperature may drop immediately after the power supply to the heating coil 3 is cut off, and may be lower than the desired temperature (predetermined set temperature). As the temperature of starch increases, water absorption proceeds. If the temperature is too low, water does not reach the center of brown rice, leading to a boiled rice. In that case, as shown in FIG. 6, based on information from at least one of the pan bottom temperature sensor 4 and the internal temperature sensor 16, a desired temperature range (a predetermined temperature range, in this case, between the temperatures T4 to T3). ) May be energized to the heating coil 3. Alternatively, the heating coil 3 may be energized with a predetermined power that maintains a desired temperature range. FIG. 6 is a diagram illustrating another example of the rice cooking process of the rice cooker 100 and the transition of the heated object temperature, the pan-like container temperature, and the energization power to the heating coil.

  In addition, when temperature T3 is more than gelatinization temperature, since water absorption advances in a shorter time, there exists an effect of leading to shortening of rice cooking time.

  On the other hand, when the temperature T3 is lower than the gelatinization temperature, the starch in the endosperm portion does not absorb water excessively, so that the texture after cooking can be prevented from being deteriorated. In addition, the water absorption time can be extended for a long time. As a result, GABA (γ-aminobutyric acid), which is said to be good for health, is increased by the action of GABA-producing enzyme having high enzyme activity in the temperature range below the gelatinization temperature. There is an effect that you can cook brown rice that contains.

  Therefore, the time of the water absorption process may be determined based on the information of the internal temperature sensor 16 or the pan bottom temperature sensor 4 instead of executing only the preset time t2. Moreover, since the fall of temperature depends on external temperature and the amount of rice cooking as mentioned above, you may judge the time of a water absorption process based on the information of an external temperature detection means or a rice cooking amount determination means. Alternatively, instead of making a determination at a preset time t2, the time after determining that the skin softening temperature has been reached (that is, time t2-t1) may be set as the predetermined time. Since the process after reaching the softening temperature of the skin is easy to proceed with water absorption, the water absorption variation in the water absorption process does not occur every time rice is cooked by setting the time after arrival to the predetermined time, and the same time each time. Finished brown rice can be served.

  In the present embodiment, the cooking device and the heating control method according to the present invention have been described with respect to a rice cooker of brown rice in a rice cooker, taking a household IH rice cooker as an example, but is not limited to a rice cooker, for example, You may apply to the heating control method using heating cookers, such as an IH cooking heater and a gas stove. If it is a heating cooker such as an IH cooking heater or gas stove, rice is cooked without the main body 1 and the container cover 2 provided in the rice cooker 100. Therefore, if the input to the heating means is stopped, the heated object in the pan-shaped container Since the temperature of the object cools quickly, even if the outside air temperature is high or the amount of cooking rice is large, the cooling means is unnecessary, and rice cooking can be performed with an ideal temperature history as shown in FIG.

  In addition, although rice cooking in brown rice has been described so far, it can be cooked deliciously by applying it to cereals such as millet that are eaten while being peeled.

  DESCRIPTION OF SYMBOLS 1 Main body, 2 Container cover, 2a Hole part, 3 Heating coil, 4 Pan bottom temperature sensor, 5 Pan-shaped container, 5a Flange part, 6 Hinge part, 7 Time measurement means, 8 Control means, 9 Cover packing, 10 Cover body, DESCRIPTION OF SYMBOLS 11 Outer lid, 11a Packing, 12 Inner lid, 12a Hole part, 12b Steam port, 13 Locking material, 14 Cartridge, 14a Steam inlet, 14b Steam outlet, 15 Operation display part, 16 Internal temperature sensor, 100 Rice cooker 200 rice, 201 water.

Claims (4)

A heating means for heating a pot-shaped container for containing an object to be heated;
Control means for controlling the heating means,
The control means includes
In the water absorption process performed in the rice cooking process for brown rice where brown rice is accommodated as the heated object in the pan-like container, the temperature of the heated object reaches or exceeds the softening temperature of the brown rice skin Then, the input to the said heating means is stopped , and the temperature of the said to-be-heated material is hold | maintained more than gelatinization temperature after that, The cooking device characterized by the above-mentioned . Having cooling means,
The control means includes
2. The cooking according to claim 1, wherein, in the water absorption step, when the temperature of the heated object reaches a softening temperature of the brown rice skin, the cooling unit is controlled to cool the heated object. vessel. Water supply means for supplying water into the pan-like container as the cooling means,
The control means includes
The water-absorbing step, when the temperature of the heated object reaches the softening temperature of the brown rice skin, operates the water supply means to supply water into the pot-shaped container. Cooking device. A heating control method comprising a rice cooking process for brown rice that cooks brown rice,
In the water absorption process performed in the rice cooking process,
When the temperature of the object to be heated contained in the pan-like container reaches or exceeds the softening temperature of the brown rice skin, the input to the heating means for heating the pan-like container is stopped, and after the input to the heating means is stopped, When the temperature of the object to be heated is lower than a predetermined set temperature, the temperature of the object to be heated is determined based on temperature information of one of the temperature of the pan-shaped container and the temperature of the object to be heated. A heating control method characterized by holding at a temperature equal to or higher than the crystallization temperature .

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