KR100368451B1 - Rice cooker and method of keeping cooked rice warm - Google Patents

Abstract

(Problem) In a rice cooker having a long-term heat retaining function in addition to the normal heat retaining function, the rice is delicious for a long time even if the heat-retaining function is set for a long time after reheating by a heater has already been performed once after the warming is started. The task is to keep warm to eat.

(Remedy) If the time S112 for which the thermal switch 17 is operated for a long time is about 4 hours after the reheating, reheating after the second time is performed about every 4 hours from the first reheating. After about 4 hours after the reheating, the second reheating is immediately performed, and the third and subsequent reheatings are performed every four hours from the second reheating (S113 to S118).

Description

RICE COOKER AND METHOD OF KEEPING COOKED RICE WARM}

The present invention belongs to the technical field of rice keeping method and rice cooker, for example, 18 hours, 24 hours even if the heat retention function is set for a long time after the warming is started and the reheating by the heater is already performed once. It is to prevent the occurrence of yellowing and off-flavor by suppressing the growth of thermophilic bacillus in rice over a long period of time.

In recent years, unlike the heater that heats the cooking pot at the time of cooking, the warm cooking by electric heater and halogen to keep the cooked rice at a constant temperature in the cooking pot to provide a warm rice for a long time A group is provided. In recent years, a long time warming function of 18 hours and 24 hours has been required to allow such cookers to eat delicious rice at any time from the diversity of lifestyles. From the past insights, the optimal temperature of the rice that feels delicious is over 90 ℃, which is just after the rice is finished, but the higher the temperature, the more dry the rice feels. have.

However, when the warming temperature of the rice is maintained at about 70 ° C. by the warming heater, the thermophilic bacteria (thermophilic bacillus) mixed in the rice multiply, and 14 to 15 hours after the start of the warming, I have left off smell from rice. The thermophilic bacillus does not die at about 100 ° C., which is the cooking temperature, but grows at 60 to 70 ° C., which is the warming temperature of the cooker. In addition, the thermophilic bacillus has a spore form and a trophic type, and if it is 80 ° C. or higher, the thermophilic bacillus, which is a nutrient form, decreases, but survives as a spore. Therefore, when the heat retention temperature is 60 to 70 ° C, the spores germinate again, become nutrient types, and multiply. In addition, the thermophilic bacilli sequentially form spores at a high rate of about 10% of the number of viable cells as they proliferate. In addition, nutrient-type thermophilic bacillus proliferated in rice, and when the number of viable bacteria reached about 10 ⁷ / g or more, odor was left out. Therefore, insulating the rice for a long time after the completion of cooking required temperature control to suppress the growth of the thermophilic bacillus.

In Japanese Laid-Open Patent Publication No. 9-276134, about 5 hours after starting the warming of the rice, the heater of the cooker is operated and the rice in the cooking pot is reheated to 80 ° C or higher, so that the thermophilic bacillus of nutritional type Insulating methods have been proposed to inhibit proliferation. This corresponds to the growth of the thermophilic bacillus mixed in the rice from about 5 hours when the heat retention was started at about 70 ° C. immediately after cooking. According to this, for example, the rice left behind for dinner was eaten for breakfast the next day, and for 14 to 15 hours after the end of cooking, the growth of thermophilic bacilli in the rice was suppressed, and the delicious rice was kept as it is.

However, in this publication, when considering long-term heat retention for 18 hours or 24 hours after the end of cooking, it is insufficient to prevent odor and yellowing due to the growth of thermophilic bacillus. Insulating methods are also proposed in which a heater of a cooker is operated every five hours. According to this, since the thermophilic bacillus in the insulated rice begins to proliferate, the proliferation of the thermophilic bacilli is suppressed in the long-term warming of the rice, thereby preventing off-flavor and yellowing from the rice.

The long-term heat retention function for reheating the rice several times as described above is generally set by operating the heat insulation switch for a long time before the start of cooking. The heater is operated, the time is measured by this timer, and the heater is operated after a predetermined time has elapsed since the start of keeping warm.

However, in the case of having a heat retaining function of reheating once after a predetermined time after the warming is started after the completion of cooking, the heat retaining switch may be operated for a long time after the reheating is already performed. For example, in a situation where rice remains after eating or when it is not possible to eat the cooked food for a while, the long-term heat insulation switch is operated after the heat has been started and reheated by the heater once. It may become. In such a case, since the long-term heat insulation function is operated at the time when the long-term heat insulation switch is operated, the timer is driven from the time point at which the long-term heat insulation switch is operated to operate the heater after a predetermined time has elapsed. Therefore, since the heater is operated at a time exceeding the originally scheduled second reheating time after the first reheating, the second reheating has already progressed, and the growth of the thermophilic bacillus in the rice is already in progress. , At 18 hours and 24 hours, they may grow to the point where the odor is neglected.

In the present invention, `` having a cooking heater for heating cooking pots when cooking and a warming heater for heating the cooking pots when warming '', the warming is started and once reheated by the heater Even if the heat retaining function is set for a long time, the task is to keep warm to eat delicious rice over a long time.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the structure of the gas collector of embodiment.

2 is a flowchart showing the flow of control after the start of the keep warming operation in the embodiment.

3 shows the temperature change when reheating the cooking pot 2 in the embodiment for 3 minutes, the solid line is the temperature change of the bottom of the rice in the cooking pot 2, the dotted line is the cooking pot 2 The temperature change of the upper part of the rice inside is shown.

4 shows the change in the number of viable bacteria (dogs / g) of thermophilic bacillus due to reheating in the embodiment.

(Explanation of symbols for main parts of drawing)

1-Cooker 2-Cooking Pot

3-External container 4-Lid body

5-gas burner 6-gas burner

7-Electric Heater 8-Temperature Sensor

9-Ignition 10-Control

11-cooking control unit 12-heating heater control unit

13-gas heater control unit 14-memory

15-thermostat control 16-cooking switch

17-extended thermal insulation switch

The technical means taken in order to solve the said subject is as follows.

As a method of keeping the rice, "The rice is kept at about 70 DEG C. after the completion of the cooking of the rice, and the cooking heater is temporarily operated at a reheating time after a predetermined time after the start of the keeping of the rice. In the method of keeping the rice reheated within a temperature range of 80 ℃ ~ 110 ℃,

If the time for which the long-term heat insulation switch is operated several times before the reheating is about 4 hours before the reheating is performed, reheating after the second time is performed about every 4 hours from the first reheating, and the reheating is performed. After about 4 hours, the second reheat is immediately performed, and the third and subsequent reheats are performed every four hours from the second reheat.

The above technical means acts as follows.

If the time for which the long-term heat insulation switch for performing the reheating is performed several times before about 4 hours has elapsed since the first reheating, the second and subsequent reheating is performed about every four hours from the first reheating. Thus, reheating after the second time is not performed about four hours after the long time thermal switch is activated, but is performed every four hours after the first reheating. Since the thermophilic bacillus of is subsequently reheated at the time of germination and proliferation, the viable cell count of the thermophilic bacillus of the nutritional type can be effectively reduced over 24 hours (refer FIG. 4).

In addition, if the time for which the long time thermal switch is operated is about 4 hours after the first reheating, the second reheating is immediately performed, and the reheating after the third time is about 4 hours from the second reheating. By performing every time, the second reheating can be reheated at a time close to the above time zone without a significant delay from the time when the spore-type thermophilic bacillus, which survives even one reheating, continues to germinate and proliferate thereafter. Do.

In this manner, after the first reheating is performed, regardless of the time for which the thermal switch is operated for a long time, the spore-type thermophilic bacterium that survives even with one reheating continues to germinate and multiply thereafter, or Since it reheats at a time near the time zone, the effect of suppressing growth on the thermophilic bacillus is large.

Moreover, the relationship between the heating temperature and heating time at the time of reheating of the said cooking heater makes the rice in a cooking pot into 1 second-5 minutes within the temperature range of 80 degreeC-110 degreeC. This means that the spore-like thermophilic bacillus maintains its number even at a cooking temperature of 100 ° C. for about 20 minutes, but the trophic thermophilic bacillus causing odor and yellowing has a heating temperature of 80 ° C. or higher. If the number decreases, it is possible to reliably suppress the growth of thermophilic bacillus that causes off-flavor and yellowing in the rice. Moreover, since the upper limit of the heating temperature of rice is 110 degrees C or less, drying of a rice can be suppressed and the rice of the bottom part in a cooking pot does not dry and harden especially. In addition, the heating time of 1 second to 5 minutes can reduce the thermophilic bacillus of the above nutritional type even by 1 second of heating, while the drying of the rice does not proceed if heating within 5 minutes. Then, when the cooking heater is stopped, the temperature is lowered to about 70 ° C. of the warming temperature in about one and a half hours (see FIG. 3). From this, it is possible to perform heating necessary for the loss of thermophilic bacillus without applying extra heat enough to dry the rice.

And a cooker, "The warming heater control part which operates and controls the said warming heater to heat-retain the rice after cooking completion at about 70 degreeC,

A cooking heater control unit which operates the cooking heater temporarily to reheat the rice within a temperature range of 80 ° C to 110 ° C by temporarily operating the reheating time after a predetermined time after the start of keeping the heating by the warming heater;

A long time warm-up switch for carrying out the reheating operation by the cooking heater several times;

Memory unit to memorize the first reheating time,

If the time for which the long time thermal switch is operated is about 4 hours after the reheating is performed based on the cooking end time in the storage unit, the second and subsequent reheatings are performed about every 4 hours from the first reheating. And after about 4 hours after the reheating, the second heat is immediately reheated, and the heat retaining control unit is configured to reheat the third time and subsequent every 4 hours from the second heat. In this case, when the rice is kept warm, the cooking heater is controlled by the heat keeping control unit, thereby having the same operation and effect as the heat keeping method.

In the above technical means, "the reheating time is 6 to 8 hours after the start of warming", the first reheating is thermophilic bacillus which is a causative bacterium that causes yellowing and odor when the rice is warmed. It germinates at around 70 degrees Celsius suitable for heat retention of rice, and it multiplies, and after initiating heat retention, this proliferation of this thermophilic bacillus fits in time of 6-8 hours (refer to FIG. 4) which is in full swing for this first reheating The proliferation inhibitory effect on the thermophilic bacillus in this is large.

And in the said cooking machine, "the said reheating time is 6 to 8 hours after starting heat retention," there exists an effect similar to this heat retention method.

According to the present invention, spore-like thermophilic bacillus, which survives even with one reheating, is subsequently germinated, even if the warming is started and once a long time warming function is set after the reheating is performed by the heater. By reheating at the time of growth or near the time, it is possible to effectively suppress the growth of thermophilic bacillus in the rice, and as a result, it is possible to eat delicious rice for a long time after finishing cooking.

Embodiment

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings.

1 is a cross-sectional view showing the configuration of a gas collector according to an embodiment of the present invention. As shown in FIG. 1, the gas cooking machine 1 which concerns on embodiment is the cooking pot 2 which accommodates and heats rice etc., and the external container 3 which accommodates this cooking pot 2, A cover body 4 attached to the outer container 3 so as to be openable and close, a gas heater 5 serving as a cooking heater provided under the bottom of the cooking pot 2, and the gas heater 5 An electric heater 7 provided to surround the gas burner 6 to be configured and a temperature sensor 8 provided to contact the bottom surface of the cooking pot 2 are provided. In the vicinity of the gas burner 6, an ignition device 9 is arranged, a cooking switch 16 for executing cooking in the upper portion, and several times of reheating operation by the gas heater 5 after the cooking is finished. The long time heat insulation switch 17 for implementing is arrange | positioned. Moreover, this gas collector 1 is equipped with the timer for measuring the heat retention time (not shown).

The gas heater 5 and the electric heater 7 are controlled to be operated by a control device 10 equipped with a microcomputer. The controller 10 includes a cooking control unit 11, a warming heater control unit 12, a gas heater control unit 13, a memory 14 for storing the first reheating time after finishing cooking, and a thermal control unit ( 15).

The cooking control unit 11 performs the cooking operation while controlling the operation of the gas heater 5 in accordance with the set cooking pattern to control the ignition timing, the extinguishing timing, the thermal power, and the like.

After the cooking operation is finished, the thermal heater control unit 12 operates the electric heater 7 to control the insulation of the cooking pot 2 at a constant temperature. In this embodiment, heat retention temperature is set to about 70 degreeC.

The gas heater control unit 13 temporarily operates the gas heater 5 at a reheating time after a predetermined time after starting the heat retention by the electric heater 7 to operate the rice in a temperature range of 80 ° C to 110 ° C. Control to reheat within. In this embodiment, the said predetermined time is set to 7 hours.

If the time for which the long time thermal insulation switch is operated by the thermal insulation control section 15 is about 4 hours after the reheating is performed from the cooking end time in the memory 14, the second and subsequent reheating operations are performed. After about 4 hours from the first reheating, after about 4 hours after the reheating, the second reheating is immediately performed, and the reheating after the third time is about 4 hours from the second reheating. Conduct.

In addition, in this embodiment, although the thermal insulation heater uses the said electric heater 7, you may employ | adopt another heat source, such as a halogen.

Next, the heat retention operation of the gas collector 1 according to the present embodiment will be described.

2 is a flowchart showing the flow of control after the start of keeping warm operation. 3 shows the temperature change when the reheating of the cooking pot 2 is performed for 3 minutes, the solid line shows the temperature change of the lower part of the rice in the cooking pot 2, and the dotted line shows the temperature of the upper part of the rice in the cooking pot 2. Each change is shown. Fig. 4 shows the change in viable cell count (dog / g) of thermophilic bacilli due to reheating.

In the present embodiment, when the cooking operation is performed, the amount of rice is detected from the heating time at which the cooking pot 2 reaches a predetermined temperature, and the like is used as the information at the time of heat retention operation. The amount of rice is detected by the cooking control unit 11 of the controller 10. First, after the cooking operation is finished, the warming operation is started. This thermal insulation is intermittently energized by the electric heater 7 while detecting the bottom temperature of the cooking pot 2 by the temperature sensor 8 in the said heating heater control part 12, and cooking pot 2 Keep the inside at about 70 ° C. Moreover, heat retention by this electric heater 7 acts effectively also during the operation of the gas heater 5 demonstrated below.

As shown in Fig. 2, when the warming operation is started, it is monitored whether or not 7 hours have elapsed since the warming control unit 15 started the warming (S101). When 7 hours have elapsed, the time at this time is regarded as the first reheating time and stored in the memory 14 in the control device 10 (S102), and then the gas heater 5 is operated as the heat retaining control unit 15. The temperature of the cooking pot 2 is raised rapidly. At this time, in the present embodiment, first, the cooking controller 11 determines the heating time by the gas heater controller 13 according to the amount of rice detected by the cooking operation (S103, S104). Thereafter, by operating the gas heater 5 (S105, S106, S107), if the amount of rice is "small", it is heated for 1 minute (S108), and if the amount of rice is "medium", it is heated for 2 minutes. (S109), if the amount of rice is "large", it is controlled to heat for 3 minutes (S110). In the present embodiment, to explain the case where the amount of this rice is "large", the temperature of the rice is about 85 ° C at the top of the rice, and the bottom of the rice (near the bottom of the cooking pot 2) is about 100 ° C. (See the 7th time of FIG. 3), The temperature of the rice in the cooking pot 2 becomes the range of 80 degreeC-110 degreeC. The number of live bacteria of thermophilic bacillus in the rice at this time was about 10 ⁴ pieces / g immediately before reheating, and is reduced to 100 or less / g or less by reheating (refer to the seventh hour in FIG. 4).

Moreover, even when the quantity of rice is "small" and "medium", it is comprised so that the temperature of a rice may be in the range of 80 degreeC-110 degreeC by each heating time. The temperature of the rice at the time of keeping warm in the range of 80 degreeC-110 degreeC is dried in the lower side of the rice in the cooking pot 2, when it exceeds 110 degreeC, and when it is less than 80 degreeC, the odor mixed in rice is Can not reduce the thermophilic bacillus of nutrients that cause and yellowing. That is, in order to reduce the number of live bacteria of thermophilic bacillus and lengthen the stop time of proliferation, it is preferable to raise the heating temperature of rice and to set the time to keep at the heating temperature. However, if the heating temperature of the rice is too high or the heating time is too long, the drying of the rice is increased, rather, the food taste is lowered. On the other hand, in order to prevent off-flavor and yellowing in rice, it is sufficient to reduce the number of live bacteria of trophic thermophilic bacillus to at least 10 ⁶ / g or less. Therefore, by raising the temperature of the rice to 80 ℃ to reduce the number of live bacteria of the thermophilic bacillus can be stopped odor and yellowing from the rice. Moreover, heating time can also be expected to reduce the live cell count of thermophilic bacilli in 1 second-5 minutes. In particular, according to the gas heater 5 as in the present embodiment, as a characteristic of gas heating as opposed to electric heating, it is possible to raise the temperature to the set temperature in a short time according to the gas fire, for example, the most heat is generated by heating for 3 minutes. It is heated up to about 100 ℃ in the rice in the bottom of the cooking pot that is easy to be applied, and is heated up to about 85 ℃ in the top of the rice difficult to apply heat (see Fig. 3). This can inhibit the growth of thermophilic bacillus causing odor and yellowing in the rice. In this regard, it is possible to perform heating necessary for the loss of thermophilic bacillus without applying extra heat such that the rice is dried.

Then, when the reheating by the gas heater 5 has passed a predetermined time (3 minutes in this example) (S110), the gas burner 6 is extinguished to terminate the operation of the gas heater 5 (S111), It returns to normal heat retention operation by the electric heater 7. Then, the rice in the cooking pot 2 is maintained at about 70 degreeC at the time of 8 hours and half which is about 1 hour and a half after reheating by the gas heater 5 is complete | finished.

Next, the reheating operation after the second time will be described.

After the first reheating has been performed, if the long-term heat preservation switch 17 for reheating is operated several times (S112), 4 hours have elapsed from the first reheating time stored in the memory 14. It is determined whether or not (S113). If 4 hours have not yet elapsed, the monitoring operation of step S113 is repeated, and the standby state continues until 4 hours have elapsed. Then, while the standby state is continued, if 4 hours have elapsed since the first reheat is performed or if 4 hours have already elapsed at the time when the thermal insulation switch is turned on for a long time in the step S112, the timer is driven ( S114), by operating the gas heater (5) by the thermal insulation control unit 15 to sharply increase the temperature of the cooking pot (2) (S115). As a heating time at this time, it operates for 3 minutes similarly to the said 1st reheating time (S116). In this example, it is assumed that the first reheating is carried out 7 hours after the start of the heat retaining, and the long-term heat retaining switch 17 is turned on 4 hours after the first reheating. Therefore, this second reheating was performed 11 hours after the start of keeping warm. Then, when the rice temperature at 11 hours is shown in FIG. 3, the rice in the cooking pot 2 is heated up within a temperature range of 80 ° C. to 110 ° C., similarly to the first reheating at the time of 7 hours. At this time, when the thermophilic bacillus in the rice was near the 11th hour in FIG. 4, the thermophilic bacillus gradually grew from the end of the first reheating and increased to about 10 ³ pieces / g immediately before the second reheating, but again by reheating 10 It can be seen that the decrease was less than / g. When the second reheating has elapsed for a predetermined time (3 minutes in this example) (S116), the operation of the gas heater 5 is terminated (S117), and the normal heat retaining operation is returned.

Subsequently, it is determined whether or not the reheating has been performed three times since the start of keeping warm (S118). That is, in this embodiment, after completion | finish of cooking, it is set so that reheating by the gas heater 5 may be performed three times after starting heat retention. At this time, since reheating is performed only twice, in this case, the process is returned to before the step S113 (S118). Then, as the third reheat, the time measured by the timer is monitored, and when 4 hours have elapsed since the second reheat was started (S113), the timer was turned on and then turned on (S114). 5) by operating for 3 minutes to sharply increase the temperature of the cooking pot (2) (S115, S116). Since the reheating of the third time is carried out 11 hours after the reheating of the second time starts warming, it is 15 hours after the start of warming. Then, the rice in the cooking pot 2 has a temperature range of 80 ° C to 110 ° C in the same manner as in the reheating of the first time when 7 hours have elapsed and the second time of reheating after 11 hours after 4 hours. It is heated up inside. As a result, when the thermophilic bacillus in the rice was near the 15th hour in FIG. 4, the thermophilic bacillus gradually grew from the end of the second reheating and increased to about 10 ² / g immediately before the third reheating, but the 10 by reheating It can be seen that the decrease was less than / g. Then, when this third reheating has elapsed for a predetermined time (3 minutes in this example) (S116), the operation of the gas heater 5 is terminated (S117).

Thereafter, after the third reheating is executed (S118), the first reheating time is cleared from the memory 14 (S119), and the normal heat retaining operation by the electric heater 7 is returned.

Thus, when the rice heat which was kept 24 hours after cooking was evaluated about 24 hours, problems, such as hardening and sticking to the bottom of the cooking pot 2, were not seen. In addition, the smell, color, and taste of the rice were not particularly disturbing. This point is that when the number of viable bacteria of thermophilic bacillus reaches about 10 ⁷ / g or more, odors, etc. are left unattended. Maintenance is supported. In addition, although there are intervals of 4 hours or more, which are the second and third time intervals, from the time of the third heating, the last reheating, to the 24 hours, the number of total thermophilic bacilli in the rice is effectively reduced by the three reheating. Therefore, it can be seen that the thermophilic bacillus did not proliferate in the number enough to leave off odors and the like even at the point of 24 hours.

As described above, in the present embodiment, even when the heat retention function is set for a long time after the heat retention has been started and the reheating by the heater has already been performed, the growth of the thermophilic bacilli in the rice can be effectively suppressed. Results After 24 hours of cooking, you will be able to eat delicious rice. That is, in rice, about 10% of the viable cells are present in spore form according to the growth of thermophilic bacillus, and after the reheating once, this spore form continues to germinate and becomes nutritional type after about 4 hours. The rapid proliferation of thermophilic bacillus can be suppressed by making the reheating time interval of every 2nd and 3rd time every 4 hours. In this embodiment, although the heat switch 17 turns on when it has not yet elapsed for 4 hours after the 1st time of reheating, although it has already passed 4 hours, the gas heater 5 immediately turns on, Since reheating is possible, the reheating can be reheated at a time close to the time zone without significantly delaying the growth of the thermophilic bacillus in the rice.

In addition, the conventional method in which reheating by the gas heater 5 during warming is finished three times in a 24-hour warming (7 hours, 11 hours, and 15 hours later), and four times of reheating are performed every five hours. Compared with Japanese Patent Application Laid-Open No. 9-276134, drying of the rice can be prevented and energy saving for one reheat can be achieved.

Moreover, in the said embodiment, although it is set as 1 minute, 2 minutes, or 3 minutes by the reheating time by the gas heater 5, you may determine suitably between 1 second and 5 minutes. In addition, although the first reheating time is 7 hours after the start of keeping warm, the first reheating time may be appropriately determined between 6 and 8 hours later.

In addition, as described above, the reheating time is defined, but since the rice at the bottom of the cooking pot 2 may be steamed depending on the amount of rice, the set temperature (cooking extinguishing temperature or cooking digestion) within the reheating time. When the temperature is lower than the temperature, for example, 110 ° C., the heating operation may be terminated by giving priority to the set temperature.

In addition, although the amount of rice was divided into three stages of public places, it was controlled to select the heating time of the gas heater 5, but it was divided in more detail according to the capacity of the cooker, the amount of rice, the capacity of the gas heater, or the amount of rice. You may decide appropriately, dividing into two stages, large and small.

In addition, the heating time of the gas heater 5 is not selected according to the amount of rice as described above, but the operation of the gas heater 5 is performed when the rice temperature in the lower portion of the cooking pot 2 reaches 110 ° C. You may control to end. This is because, when the lower rice temperature reaches 110 ° C, the upper rice temperature is estimated to reach 80 ° C or higher, and as the rice temperature in the cooking pot 2 is generally solved within the range of 80 ° C to 110 ° C. .

In addition, although the gas heater 5 is used for the said reheating, you may use an electric heater for this reheating, In this case, you may combine with the said electric heater 7 which normally insulated, and it separates from this You may install a dedicated electric heater. And like this example, you may apply not to a gas cooker but an electric cooker. In this electric cooker, the electric heater which cooks and the electric heater which heat-insulates normally may also be used for the said reheating, and separately You may provide the electric heater exclusively for reheating. However, the electric heating is slightly inferior in the temperature increase rate and the spread of heat to the rice compared with the gas heating, but it is sufficient to suppress the growth of the thermophilic bacilli in the rice.

On the other hand, the second and third reheating times are set to be the same reheating time as the first, and the maximum temperature at the bottom of the cooking pot 2 at the time of the first reheating is controlled by the memory of the control device 10 or the like. The reheating of the second and third times may be controlled to be terminated when the temporary temperature is reached.

Claims (4)

It is provided with the cooking heater which heats the cooking pot at the time of cooking, and the heat retention heater which heats the said cooking pot at the time of warming, After the rice is finished cooking, the warming heater is used to keep the rice at about 70 ° C, while the cooking heater is temporarily operated at a reheating time after a predetermined time after the start of the warming, and the rice is heated at a temperature of 80 ° C to 110 ° C. In the method of keeping the rice reheated within the range, If the time for which the long time thermal switch for causing the reheating is performed several times before about 4 hours has elapsed since the reheating is performed, reheating after the second time is performed about every 4 hours from the first reheating, and the reheating is performed. After about 4 hours, the second heat is immediately reheated, and the third and subsequent reheats are performed about every 4 hours from the second reheating. The method according to claim 1, The said reheating time is 6 to 8 hours after starting heat retention, The heat insulation method of the rice characterized by the above-mentioned. In the cooking apparatus provided with the cooking heater which heats the cooking pot at the time of cooking, and the heat retention heater which heats the said cooking pot at the time of warming, An insulating heater control unit for controlling the heating to keep the rice after cooking at about 70 ° C. after finishing cooking; A cooking heater control unit which temporarily operates the cooking heater at a reheating time which is a predetermined time after the start of keeping the heating by the insulating heater, and controls the rice to be reheated within a temperature range of 80 ° C to 110 ° C; A long time warm-up switch for performing the reheating operation by the cooking heater several times; Memory unit to memorize the first reheating time, If the time for which the long-term heat preservation switch is activated is about 4 hours after the reheating operation is calculated from the end time of cooking at the storage unit. The second and subsequent reheats are performed about every four hours from the first reheating, and after about four hours after the reheating, the second reheating is performed immediately, and the third and subsequent reheatings are performed on the second time. Cooker characterized in that it is provided with a thermal insulation control unit to be carried out about every four hours from reheating. The method according to claim 3, The said reheating time is 6 to 8 hours after starting heat retention, The cooking machine characterized by the above-mentioned.