JP2004286439A - High-frequency heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To satisfactorily heat-cooking a variety of foods by controlling an environment where the foods are placed in a food heat-cooking method for rapidly heat-cooking the foods at optimum temperatures while maintaining the foods at excellent quality. <P>SOLUTION: The foods 19 are stored in a heating chamber 13. A steam generator 15 is controlled according to the advancement of heating of the foods 19 to vary temperature and humidity in the heating chamber 13 so as to control an environment in the heating chamber to an environment near the foods after the heating of the foods 19 is completed. Microwave radiated to the foods 19 is controlled to rapidly heat-cook the foods without allowing heat and water to be removed by the environment surrounding the the foods. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a food heating and cooking method for quickly cooking various foods to an optimum temperature while maintaining good quality.

  Conventionally, as a food heating method of this kind, a food thawing type cooking furnace described in Japanese Patent Publication No. 55-51541 has been known. Hereinafter, the configuration will be described with reference to FIG. As shown in FIG. 8, the conventional food thawing type cooking furnace includes a stirrer 3 on a ceiling 2 in a freely sealable furnace 1, and a magnetron irradiation unit 4 is disposed near the stirrer. In the furnace 1, there is provided a detachable food placing shelf 5 under which a detachable liquid dish 6 of water, oil or the like, into which the food A can be immersed, is disposed. A heater 7 is provided. By the combination of the magnetron irradiating unit 4 and the liquid-introducing dish 6 with the heater 7, heating by magnetron irradiation from above and steam heating by boiling water from below can be used together.

  With such a configuration, when heating the frozen food, the stagnation in the maximum ice crystal formation zone that causes the destruction of the cell membrane of the food during thawing is eliminated, and the umami component is less quickly spilled by passing the frozen food immediately, and the thawing unevenness is reduced. No uniform thawing heating can be realized. The thawing conditions when passing through the maximum ice crystal formation zone are as follows: the ideal thawing and finishing of frozen foods by selecting the combination of internal heating magnetron irradiation and steam generation and steam heating in accordance with the menu type ( Cooking). In addition, this prior art enables various cooking methods corresponding to various types of frozen foods. For example, put oil in the liquid dish to defrost the frozen cooked food such as fries and tempura, or remove the liquid dish and leave the frozen pack with magnetron irradiation and hot air heating by the heater (hot air is blown by the stirrer on the ceiling). And stirring are used together. Furthermore, it is described that since steam is generated, it can be used as a bread and cake processor in all steps of thawing frozen bread and frozen cakes and baking fermentation.

  However, in the conventional food heating method, a combination of magnetron irradiation and steam heating is selected according to the menu type, oil is thawed by putting oil in the liquid tank, or magnetron irradiation and the heater are removed by removing the liquid tank. Although the configuration to use together with hot air heating is disclosed, when using microwave heating and steam heating for each menu type, the key point is only how quickly the maximum ice crystal formation zone is passed. There is no description about a device for performing the heating cooking after being placed and passing therethrough, that is, after thawing.

  When actually heating various frozen foods with microwaves while generating steam, steamed dishes such as sweet potatoes and meatballs are moist and better than steam adding water to the food surface and heating with microwaves alone Although it will be finished, the inside ingredients are easier to absorb microwaves than the outer skin, so the temperature of the ingredients alone becomes too high, or when heating the fried frozen food such as fries and tempura, the steam on the food surface However, there is a problem that the clothes are sticky and the original crispy texture is impaired. In addition, when the baked frozen bread was heated, the bread dough was overheated with hot steam as in the case of tempura batter, and the fragrance and texture were impaired. Furthermore, in confectionery bread coated with chocolate or sugar, there is a problem that the coating melts or the gloss becomes poor.

  Here, the concept of the conventional heating will be described with reference to the drawings. FIG. 9 is a diagram showing the environment in the heating chamber and the heating state of the food in the conventional steam heating. The horizontal axis represents the elapsed time from the start of heating, and the vertical axis represents the temperature and humidity in the heating chamber and the heating state of the food. . Steaming dishes are different, as the optimal heating condition of the food was not taken into account, but excessive humidity added unnecessary moisture to the food, and excessive ambient temperature caused the temperature of the food to exceed the proper level. Had risen, impairing its workmanship. The above-mentioned invention, which proposes the combined use of microwave heating and steam heating, still has such a problem.

  FIG. 10 is a diagram showing the environment in the heating chamber and the heating state of the food in the conventional microwave heating, in which the horizontal axis represents the elapsed time from the start of the heating, and the vertical axis represents the temperature / humidity in the heating chamber and the heating of the food. State. Conventional microwave heating does not pay attention to the environment inside the heating room, and the food is thrown into a dry heating room with a low temperature, so the moisture of the food is lost to the atmosphere and the temperature of the food that has risen On the other hand, heat was exchanged with the cold air from the food surface, and it had dropped.

  The present invention solves such conventional problems, and is based on the discovery that these were caused by inconsistencies between the finished food condition and the environment in the heating chamber.

  Therefore, by heating the environment in the heating room to approximately match the environment that can maintain the temperature and moisture content of the food in a state where the food is optimally cooked, that is, the environment near the food when the food is completely heated, During cooking, the food is not deprived of heat or moisture, conversely, it does not reach an excessive temperature or add too much water, and when cooking is completed, the food and the environment of the heating room are not Heating in an optimal state without heat or moisture transfer between them can be realized.

  The present invention adjusts the environment in the heating chamber, especially the temperature and humidity to match the environment near the food at the time of completing the heating of the food, and performs microwave heating to produce not only frozen foods but also various foods. A first object is to quickly heat and cook in a proper state.

  In addition, the environment of the heating room is adjusted to match the environment near the food at the time of the completion of the heating of the food, and the microwave output irradiating the food is changed during the heating to balance the temperature rise between the outside and inside of the food Weighing, cooking at an appropriate temperature and in a good condition.

  In addition, after the heating is completed, the heating completion state of the food is temporarily held until the food is taken out of the heating chamber.

  The present invention provides a heating chamber for accommodating food, a steam generator for supplying water from a water supply tank and generating steam using a temperature control heater, microwave generating means for irradiating microwave to the food, A control unit for controlling the steam generator and the microwave generation means, and the control unit controls the steam generator to generate steam, thereby adjusting the temperature and humidity in the heating chamber to a heating completed state. Then, the vapor is condensed on the food surface by the temperature difference between the environment and the food to form a film of moisture, and thereafter, the power supply to the microwave heating generation unit is started. Even after the power supply to the generator is stopped, the power supply to the steam generator is continued for a predetermined time.

  The high-frequency heating device of the present invention includes a heating chamber for storing food, a steam generator for supplying water from a water supply tank and generating steam using a temperature control heater, and a microwave generation unit for irradiating microwaves to the food. A control unit for controlling the steam generator and the microwave generating means, wherein the control unit controls the steam generator according to the food to change the environment in the heating chamber near the food when the heating of the food is completed. Since the configuration is adjusted to the environment and the microwaves are irradiated to the food by the microwave generation means, not only frozen foods but also various foods can be quickly cooked in a good condition close to freshly prepared.

  According to the configuration described above, according to the heating method input from the input unit, the present invention controls the environment adjustment unit and the microwave generation unit to control the environment in the heating chamber according to a predetermined heating condition in the storage unit. Since the food is adjusted to match the environment near the food when heating is completed, it is possible to prevent the food from being deprived of heat as the heating progresses or to reach an excessively high temperature, and also prevent excessive loss of water. Therefore, not only frozen foods but also various foods can be quickly cooked in a good condition close to freshness.

  Further, since the microwave output can be varied or the timing of environmental adjustment can be selected, the temperature rise between the outside and the inside of the food is balanced, and the food can be cooked at an appropriate temperature and in a good state without uneven heating. Things.

  Further, since the energization to the environment adjusting means is continued until the door of the heating chamber is opened after the heating is completed, the heating completion state of the food can be held for a while.

  Further, by directly detecting the environment of the heating chamber, the environment of the heating chamber can be surely adjusted to a predetermined state.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 4 is an external view of a heating device according to the food heating method of the present invention. A door 9 is supported on the front surface of the main body 8 so as to be openable and closable, and closes an opening of a heating chamber in which food is stored. The operation panel 10 is provided with a heating command key 11 serving as an input means, and codes entered in one digit or several digits are used to determine the type and quantity of food, storage temperature (such as frozen or chilled storage), heating completion temperature, and the like. The information for determining the law is instructed to the control unit. The operation of the control unit will be described later. A water supply tank 12 is detachably provided on the right side of the main body.

  FIG. 5 is a front sectional view of the heating chamber. In the heating chamber 13, a magnetron 14 which is a microwave generating means for irradiating a microwave and a steam generator 15 which is an environment adjusting means are connected. The steam generator 15 includes a boiler 16, an atomizer 17 having an ultrasonic vibrator, and a temperature control heater 18. The water supplied from the water supply tank 12 to the boiler 16 is dispersed by the atomizer 17 into fine water droplets. Then, the temperature control heater 18 heats the atomized fine water droplets to raise the temperature to a desired temperature. The steam generator 15 can generate air having a desired temperature and a desired humidity by controlling the operation of the atomizer 17 and the input of the temperature control heater 18. The food 19 is placed on a placing plate 20 having a number of small holes or slits.

  FIG. 6 is a block diagram showing the configuration of the control system. The control unit 21 decodes the heating command code input from the heating command key 11 and reads out the specified heating conditions from the memory 22 as storage means. As the heating conditions, control data of the steam generator 15, that is, data indicating operation control of the atomizer 17 and input control of the temperature control heater 18 and data indicating power supply conditions to the magnetron 14 are stored. The control unit 21 controls the power supply to the atomizer 17, the temperature control heater 18, and the magnetron 14 based on the read control data, and controls the temperature and humidity of the steam introduced into the heating chamber 13, The wave output is controlled as predetermined.

  Foods have a characteristic in how the temperature rises because the penetration distance of electric waves and the dielectric loss coefficient differ depending on the type of food, and can be roughly classified into three groups based on experience. FIG. 7 is a diagram showing a heating state of a cross section of a food in microwave heating, and FIG. 7 (a) shows an example in which the temperature of the inside and the end thereof rises relatively uniformly, such as pasta and cooked rice, FIG. 7 (b) shows an example in which the inside heats up before the end, for example, shrimp tempura, small bread, shumai, etc. FIG. It is. Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1, 2 and 3. FIG.

  FIG. 1 is a view showing a method of heating a food in which the temperature of the inside and the ends thereof rises relatively uniformly as described in FIG. 7A, and FIG. 1A shows the inside of a heating chamber during heating according to the present invention. It is a diagram which shows temperature and food temperature, and the figure (b) has shown the transition of the humidity in a heating room, and the figure (c) has shown the state of the microwave output, respectively. In FIG. (A), the temperature of the food starting from the freezing temperature (−20 ° C.) gradually increases because it absorbs only a small amount of microwaves up to the maximum ice crystal formation zone (−5 to −1 ° C.). In the maximum ice crystal formation zone, the energy passes through the melting of the ice and passes after some time (point A). Then, after time A, the food rapidly absorbs microwaves and the food temperature begins to rise sharply. Since it takes some time for the temperature and humidity of the heating chamber to reach the heating completion state in FIGS. (A) and (b), the microwave in FIG. The output is adjusted according to the food. Note that it is not necessary to reduce the output to a lower output after the time point A for a food product having a relatively uniform temperature rise inside and at the end of the food product. Since the environment in the heating chamber is adjusted according to the heating completion state, the food is appropriately warmed from the surface by the latent heat of the steam. At the same time, the food is heated from the inside by the microwave, so that at the end of the cooking, the inside and the end of the food are heated to a suitable temperature in a well-balanced manner and quickly. Since the water on the surface of the food is kept at an appropriate level, the food can be cooked in a good condition without drying, sticking, or sticking the pasta or cooked rice.

  FIG. 2 is a diagram showing a method for heating food in which the temperature rises at the center portion before the end portion described in FIG. 7B, and FIG. 2A shows the inside of the heating chamber during heating according to the present invention. It is a diagram which shows temperature and food temperature, FIG. B) shows transition of humidity in a heating room, and FIG. If the food starts at the freezing temperature (-20 ° C), if microwaves are radiated from the beginning, the radio wave penetrates into the center of the food and warms first from the center, so the heating chamber as shown in Figures (a) and (b) The temperature and humidity are immediately adjusted to the heating completed state, and first, steam is condensed on the food surface by the temperature difference between the environment and the food, and a moisture film is formed by the temperature of the environment. When microwave heating is started as shown in FIG. 3C at the time when the food surface has begun to melt (time point A), a part of the microwave which is not so much absorbed in the frozen state is also absorbed in the surface layer of the food. As a result, the food is heated in a well-balanced manner from inside and outside. For this reason, Shumai can be warmed up evenly without being too hot when chewed, even though it was at the right temperature when put in the mouth. The surface is moist and delicious.

  Since there is no overheating inside the baked frozen bread, the elasticity and aroma of the bread dough are maintained, and the bread does not sticky and rises like freshly baked bread. With shrimp tempura, the shrimp and shrimp heat up to almost the same temperature, so the shrimp does not overheat and is soft and tasty. Good cooking can be achieved without the moisture of the shrimp migrating to the clothes and sticking.

  According to the experiment, the clothes were moist immediately after heating was completed, compared to heating only with microwaves.However, the excess water gradually evaporated, and by the time they were served on the table, they were finished like tempura clothes. . Further, it has been confirmed by experiments that these foods have less weight loss before and after heating as compared to the case where they are heated only by microwaves.

  FIG. 3 is a view showing a method for heating food in which the end portion described with reference to FIG. 7 (c) rises in temperature before the center portion, and FIG. 3 (a) shows the inside of a heating chamber during heating according to the present invention. It is a diagram which shows temperature and food temperature, and the figure (b) has shown the transition of the humidity in a heating room, and the figure (c) has shown the state of the microwave output, respectively. In FIG. (A), the temperature of the food starting from the freezing temperature (−20 ° C.) passes through the maximum ice crystal formation zone (−1 to −5 ° C.) after some time (time A).

  From the start of heating to this point A, the food absorbs only a small amount of microwaves and the penetration of microwaves inside the food is good, so that the microwave output is high in the first half as shown in FIG. Irradiates frozen food at the output. At this time, it is important to prevent the surface of the food from melting or adsorbing moisture as much as possible in order to improve the penetration of the microwave into the food. Therefore, adjustment of the temperature and humidity in the heating chamber is refrained until the food starts to partially melt (time A), as shown in FIG. That is, thawing is mainly performed by microwave heating that penetrates particularly deeply when the food is frozen, and the temperature and steam are suppressed.

  Then, after the time point A, the food rapidly absorbs the microwave while the melted portion and the unthawed portion are mixed. As described above, the thawed portion (moisture) shows a dielectric loss several times to several tens times that of the frozen portion, so that the temperature difference between the thawed portion and the unthawed portion increases. Therefore, as shown in FIG. 3C, the microwave output is reduced to a fraction of the total output, and heating is continued while conducting heat from a high-temperature portion to a low-temperature portion. The temperature and the humidity in the heating chamber are adjusted from the time A to the state in which the food is completely heated as shown in FIGS. Help to do. Furthermore, even if the surface temperature reaches the heating completion temperature in FIG. (A) (time B), if the internal temperature is low, the microwave irradiation is terminated at time B as shown in FIG. As shown in (b), the temperature control and humidity control are continued, and the internal temperature is increased. In this way, the inside of a hamburger or curry can be heated to an appropriate temperature while preventing the ends from being overheated and becoming hard or boiled down.

  Further, after the heating is completed (time point C), only the environmental adjustment is continued until the door of the heating chamber is opened and the food is taken out, and the warmed food can be kept warm without impairing the workmanship.

  The control unit searches the memory for control data of the steam generator and magnetron corresponding to the type and quantity of food, the starting temperature (whether frozen or chilled, etc.), the heating completion temperature, etc. according to the code input from the heating command key. Since the data can be read, the control may be executed every moment based on the data.

  In the present embodiment, a configuration in which heating is performed according to a heating method input from the input unit and in accordance with a predetermined heating condition in the storage unit without a detection unit such as a sensor is described. Detecting means for measuring the environment and feeding back the power supply to the steam generator may be provided. Such a detecting means includes a temperature detecting means and a humidity detecting means.

  Further, the steam generator, which is an environment adjusting means, is not limited to the configuration described in the embodiment. Of course, a steamer in which a heater is thrown into a boiler or a sheathed heater is brazed to the outer wall of the boiler is also applicable.

(A) A diagram showing the temperature in the heating chamber and the heating state of the food, showing the first embodiment of the present invention. (B) A diagram showing the humidity in the heating room. (C) A diagram showing the state of the magnetron output. (A) A diagram showing the temperature in the heating chamber and the heating state of the food, showing the second embodiment of the present invention. (B) A diagram showing the humidity in the heating chamber. (C) A diagram showing the state of the magnetron output. (A) A diagram showing the temperature in the heating chamber and the heating state of the food, showing the third embodiment of the present invention. (B) A diagram showing the humidity in the heating chamber. (C) A diagram showing the state of the magnetron output. External view of the heating device Front sectional view of the same heating chamber Block diagram showing the configuration of the control system (A), (b), (c) Diagram showing rise in microwave heating temperature inside and on the surface of food Front sectional view of the heating chamber of a conventional food thawing type cooking furnace Diagram showing the heating state of the food and the temperature in the heating chamber Diagram showing the temperature of a conventional microwave heating chamber and the heating state of food

Explanation of reference numerals

11 Heating command key (input means)
13 heating room 14 magnetron (microwave generating means)
15 steam generator (environmental adjustment means)
21 control unit 23 temperature sensor (environment detection means)
24 Humidity sensor (environment detection means)

Claims (3)

A heating chamber for accommodating food, a steam generator for supplying water from a water supply tank and generating steam using a temperature control heater, microwave generating means for irradiating microwaves to the food, and generating the steam according to the food. And a control unit for controlling microwave generating means, the control unit controls the steam generator to generate steam, thereby adjusting the temperature and humidity in the heating chamber to a heating completed state, The vapor is condensed on the food surface by the temperature difference between the environment and the food to form a film of moisture, and thereafter, the power supply to the microwave heating and generating means is started, and further to the microwave generating means according to the food. A high-frequency heating device configured to continue supplying power to the steam generator for a predetermined period of time even after power supply is stopped. A heating chamber for accommodating food, steam generating means for supplying water from a water supply tank and generating steam using a temperature control heater, microwave generating means for irradiating microwaves to the food, and controlling the temperature according to the food; A control unit that controls a heater and a microwave generation unit, wherein the control unit controls the steam generation unit to generate steam, thereby adjusting the temperature and humidity in the heating chamber to a heating completed state, Due to the temperature difference between the environment and the food, the vapor is condensed on the surface of the food to form a film of moisture, and thereafter, the power supply to the microwave heating and generating means is started, and the power is supplied to the microwave generating means according to the food. A high-frequency heating apparatus configured to continue energizing the steam generator even after stopping the operation until the door that closes the opening of the heating chamber is opened. A heating chamber for accommodating food, a steam generator for supplying water from a water supply tank and generating steam using a temperature control heater, microwave generating means for irradiating microwaves to the food, and generating the steam according to the food. And a control unit for controlling microwave generating means, the control unit controls the steam generator to generate steam, thereby adjusting the temperature and humidity in the heating chamber to a heating completed state, A high-frequency heating apparatus configured to condense the vapor on the surface of the food due to a temperature difference between the environment and the food to form a film of moisture, and then start supplying power to the microwave heating generation unit.

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