JP2011072706A - Rice cooker and control method for rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rice cooker boiling up rice excellent in eating quality and an control method for the rice cooker. <P>SOLUTION: A control section 8 drives a heater 12 and an agitating blade 136 for agitating the immersed rice using the temperature measured by a temperature sensor 9 and a control program responding to inputting the information of the start command of a cooking process from an operation section 94. Total number of times for the agitating blade 136 to agitate the content in the rice cooking process is controlled based on the information specifying the intensity of abrading. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rice cooker and a rice cooker control method, and more particularly, to a rice cooker having a function of rubbing rice grains and a rice cooker control method.

  Conventionally, various rice cookers are commercially available for cooking delicious rice, but even if the same rice cooker is used depending on the storage state of rice in each home after rice polishing, the cooked rice will be different. In other words, it can be cooked delicious immediately after milling, but if it is stored at room temperature after milling, the lipid layer on the milled rice surface will gradually oxidize, resulting in a lack of water absorption, often resulting in cooking rice that does not feel delicious. there were. In particular, from the rainy season to summer, the oxidation rate of the lipid layer increases as the room temperature rises, and the taste of cooked rice that is obtained by cooking rice from August to September just before new rice comes out decreases.

  Various rice milling machines for home use have been proposed for the problem that the taste of cooked rice deteriorates due to the preservation of rice. If a rice mill for home use is used, for example, brown rice can be polished only in the amount to be cooked before cooking rice, so that there is an advantage that delicious rice can be cooked.

  The rice milling machine disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2000-210574) makes the rice milling mechanism usable up to the washing of rice. In other words, the brown rice put in the separated rice cake can be milled with a blade, and the white rice put in the separated rice cake can be washed with the blade by being wet with water or with the blade.

  Patent Document 2 (Japanese Patent Application Laid-Open No. 2-245243) shows an underwater rice milling apparatus. According to the underwater rice milling apparatus, rice milling and rice scouring can be performed simultaneously by subjecting the rice grains to underwater rice polishing in a floating state.

  Patent Document 3 (Japanese Patent Application Laid-Open No. 6-63429) discloses a rice milling method that does not leave rice bran components on the surface of rice.

JP 2000-210574 A JP-A-2-245243 JP-A-6-63429

  According to the rice mill for domestic use of patent document 1, compared with the rice milling apparatus of patent document 2 and 3, it has the characteristics that it can be rice-milled just before rice cooking, and can be subsequently washed. However, household rice mills are still not popular, and in many homes, the milled rice is sold at retail stores and the rice in the polished state is stored at home. Therefore, there was a situation where the rice surface lipid had to be eaten.

  Therefore, an object of the present invention is to provide a rice cooker that cooks cooked rice with excellent taste and a method for controlling the rice cooker.

  According to one aspect of the present invention, a rice cooker that holds a pot containing rice and water for immersing the rice and controls the time and temperature for heating the held pot includes heating means for heating the pot, Temperature measuring means for measuring the internal temperature, rubbing means for rubbing the rice grains soaked in the water of the pan in the rice cooking process, and the surface part of the rice grain that is scraped off from the rice grains by rubbing and moves to the water side And means for removing.

  Preferably, it further includes a control unit for driving the heating unit and the rubbing unit using the temperature information measured by the temperature measuring unit in response to the input of the information on the start instruction of the rice cooking process.

  Preferably, the period during which the rubbing means is driven is set within a period from when the rice cooking process is started until the temperature measured by the temperature measuring means rises by heating and indicates the gelatinization start temperature of rice.

  Preferably, the removing means includes a sheet-like member having an oil adsorbing function placed on the water surface in which the rice in the pan is immersed.

  Preferably, the removing means includes a flat plate member that is placed on the immersed rice in the pan and has a plurality of holes through which the boiling rice grain surface layer portion passes.

  According to another aspect of the present invention, a rice cooker that holds a pot containing rice and water for immersing the rice and controls the time and temperature for heating the held pot includes heating means for heating the pot, In response to the input of the temperature measurement means for measuring the temperature inside the rice, the rubbing means for rubbing the rice grains soaked in the pot water in the rice cooking process, and the information on the start instruction of the rice cooking process , Using the temperature information measured by the temperature measuring means, a control means for driving the heating means and the rubbing means, and an informing means for informing the driver to stop the driving of the rubbing means and replace the water in the pot And comprising.

  Preferably, the period during which the rubbing means is driven is set within a period from when the rice cooking process is started until the temperature measured by the temperature measuring means rises by heating and indicates the gelatinization start temperature of rice.

  The control method of the rice cooker which hold | maintains the pot in which the water which immerses rice and the rice soaking according to the other situation of this invention is stored, and heats the held pot has the following characteristics.

  In other words, the rice cooker removes the heating means for heating the pot, the rubbing means for rubbing the rice grains soaked in the water in the pot, and the surface layer part of the rice grains that are scraped off from the rice grains and moved to the water side by rubbing. And a control method comprising the steps of measuring the temperature inside the pan, and responding to the input of the information on the start instruction of the rice cooking process, using the measured temperature information, and the heating means And driving the rubbing means.

  The control method of the rice cooker which hold | maintains the pot in which the water which immerses rice and the rice soaking according to the other situation of this invention is stored, and heats the held pot has the following characteristics. The rice cooker includes heating means for heating the pot and rubbing means for rubbing the rice grains immersed in the water of the pot. The control method drives the heating means and the rubbing means using the measured temperature information in response to inputting the information of the step of measuring the temperature inside the pan and the start instruction of the rice cooking process. A step and a step of notifying the driving of the stirring means to stop so as to replace the water in the pot.

  According to the present invention, the surface layer portion containing the lipid oxide layer of rice is moved to the water side by rubbing the rice grains soaked in the rice cooking step, and removed by means for removing the surface layer portion transferred to the water side, or By removing it by exchanging water, it can be cooked into cooked rice with excellent taste.

It is a schematic hardware block diagram of the rice cooker which concerns on embodiment. It is a figure which shows the structure of the control part of the rice cooker which concerns on embodiment. It is a functional lineblock diagram concerning control of a rice cooker concerning an embodiment. It is a block diagram of the operation part and display part which concern on embodiment. It is a figure explaining the attachment aspect of the stirring member and inner pot which concern on embodiment. It is a figure which shows the structure of the stirring part which concerns on embodiment. (A)-(C) are the figures explaining the basic rice cooking process which concerns on embodiment, and a rubbing period in association. It is a figure explaining the rice cooking process which concerns on embodiment. It is a figure explaining the other rice cooking process which concerns on embodiment. It is a figure explaining the other other rice cooking process which concerns on embodiment. It is a figure explaining the other other rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a processing flowchart of the rice cooking process which concerns on embodiment. It is a figure explaining the structure of the other stirring member which concerns on embodiment. It is a figure explaining the sheet | seat which concerns on embodiment. It is a figure explaining the catcher which concerns on embodiment. It is a figure which shows the detection test result of the fatty acid degree which concerns on embodiment. It is a figure explaining the taste test result by the presence or absence of rubbing which concerns on embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  In the rice cooking process of the present embodiment, by rubbing the rice grains soaked in water in the inner pot of the rice cooker, the oxidized lipid layer on the surface of the rice grains is scraped off and transferred to the water side, and the transferred oxidized lipid component is removed. .

  Referring to FIG. 1, the rice cooker according to the present embodiment includes a main body 1 having an opening upward, an inner pot 31 accommodated in the main body 1, a pivot shaft (hinge shaft) and a latch (not shown). And a lid 2 connected to the main body 1 so as to be opened and closed by a mechanism 2A. An inner lid 4 is integrally attached to the lid 2. Inside the main body 1, there are an outer pan 32 that constitutes a housing portion of the inner pan 31, a sheathed heater (hereinafter simply referred to as a heater) 12 for heating and keeping the food contained in the inner pan 31, and a rice cooker. The control part 8 which controls operation | movement of this, the temperature sensor 9 which detects the temperature of the inner pot 31, the power supply part 10, the stirring part 13 for the above-mentioned rubbing, and the fan 7 are provided. In order to accept the user's command in the case of the lid 2, the steam cylinder 5 for escaping the water vapor generated in the inner pot 31 during cooking to the outside, the display unit 93 for outputting information indicating the operation state of the rice cooker An operation unit 94 including buttons to be operated is provided. An air intake 6 </ b> A and an outlet 6 </ b> B related to the fan 7 are provided on the side surface of the main body 1.

  In order to remove the oxidized lipid layer that has been scraped from the surface of the rice grain and transferred to the water side, a method in which the user replaces the immersion water and a rice catcher 51 (hereinafter simply referred to as a catcher) or a rice cooking sheet 52 (hereinafter simply referred to as a sheet). Method). In the latter method, the catcher 51 is placed on the rice soaked in the water in the inner pot 31 before the rice cooking is started, and the rice cooking sheet 52 is floated on the water. Details of these will be described later.

  A temperature sensor 9 is provided to predict and measure the temperature of the contents (rice, water) accommodated in the inner pot 31. The temperature sensor 9 is provided so that the temperature of the bottom wall surface of the inner pot 31 can be measured. The pot bottom wall surface temperature is assumed to be equal to the temperature of the contents (rice, water) accommodated in the inner pot 31.

  The inner pot 31 can be freely put in and out of the outer pot 32. The inner surface of the inner pot 31 containing the cooked food is subjected to fluororesin processing, and the side surface in contact with the outer pot 32 is coated with hollow glass beads. With the hollow glass bead coat, heat is contained in the inner pot 31 and the heat storage effect during heat retention is increased. The inner lid 4 covers the opening of the inner pot 31 when the lid 2 is closed. The inner lid 4 is detachably attached to the lid 2.

  The stirring unit 13 includes a rotating unit 14 having a stirring blade 136 provided on the bottom surface of the inner pot 31 and a motor unit (a motor unit 15 described later) for rotating the stirring blade 136 of the rotating unit 14. The stirring blade 136 is integrally connected to the rotating unit 14, and the rotating unit 14 connected to the motor unit rotates in conjunction with the rotation of the motor unit, so that the stirring blade 136 is flush with the bottom surface of the inner pot 31. Rotate inside. At the time of rotation, since the rice contained in the inner pot 31 is immersed in water, the rice collides with the stirring blade 136 by the rotation of the stirring blade 136 and is rubbed into the inner pot 31. A water stream (thin arrow in the figure) is generated and the soaked rice grains are rubbed together.

  The display unit 93 and the operation unit 94 are integrally provided on the surface of the casing of the lid 2 in the present embodiment. However, the display unit 93 and the operation unit 94 are attached if the display information can be visually recognized by the user and the buttons can be operated. The position is not limited here.

  The fan 7 rotates at the time of the heat transfer transition after cooking. The rotation of the fan 7 causes air to enter from the intake port 6A (thick arrow in the figure), and the invaded airflow is blown to the inner pot 31 and the outer pot 32 and sent out from the outlet 6B. By blowing, the inner pot 31 itself is rapidly cooled, and the oxidation of the cooked rice in the inner pot 31 at the time of heat transfer is suppressed.

  The rice cooker is connected to a commercial power source (not shown) via the power cord 11. The power supplied from the commercial power supply is supplied to each unit via the power supply unit 10.

  In the present embodiment, the heater 12 is used as a heat source for heating and heat retention, but the heat source is not limited to this. For example, it may be based on IH (Induction Heating). In this case, both are arranged so as not to interfere with the magnetic field for the rotation mechanism of the stirring unit 136.

  FIG. 2 shows the internal configuration of the control unit 8 and its peripheral circuits. Referring to FIG. 2, control unit 8 includes a CPU (Central Processing Unit) 81, a memory 82 for storing programs and data, a timer 83 for measuring time and outputting timed data, and for inputting / outputting data to / from each unit. An I / F (Interface) 84 is provided.

  The CPU 81 controls the display operation of the buzzer 90 for notification, the open / close sensor 91, the heater drive unit 92 for energizing the heater 12 to perform a heat generation operation, the operation unit 94, and the display unit 93 via the I / F 84. Display control unit 931, motor drive unit 95 of stirring unit 13, fan drive unit 96 of fan 7, weight sensor 97 for measuring the weight of the contents in inner pot 31, and temperature sensor 9 and input / output data. To do. The opening / closing sensor 91 is provided in association with the hinge of the mechanism 2 </ b> A and detects opening / closing of the lid 2.

  FIG. 3 shows a functional configuration for controlling the rice cooker according to the present embodiment. Referring to FIG. 3, CPU 81 is determined as a course determination unit 71 that selectively determines a rice cooking course indicating a procedure for controlling each part related to the rice cooking process in accordance with an instruction input through a button operation of operation unit 94. A control procedure determining unit 72 that searches the memory 82 based on the cooked rice course and reads the corresponding control program PR, a rice amount determining unit 73 that detects the weight of the rice in the inner pot 31 based on the detection signal of the weight sensor 97, Based on the detection signal of the quantity determination unit 73, a rotation number determination unit 74 that determines the rotation number of the motor of the stirring unit 13 per unit time, generates a voltage signal for rotating the motor according to the determined rotation number, and a motor drive unit 95, a motor control unit 75 that outputs to the heater 12, a heater control unit 76 that generates a current signal supplied to the heater 12 and outputs the current signal to the heater drive unit 92, and a buzzer 90 is controlled. That includes a notification unit 77.

The motor control unit 75 controls the agitation motor 131 via the motor drive unit 95.
The memory 82 stores in advance a control program PR corresponding to each rice cooking course. The control program PR indicates information for controlling the current level applied to the heater 12 serving as a heating means in time series over a period from the start to the end of rice cooking and information for controlling the rotation of the stirring blade 136.

  Here, the weight of the rice in the inner pot 31 is measured using the weight sensor 97, but the measurement method is not limited to this. For example, it may be detected based on the load of the motor that rotates the inner pot 31, or the weight of rice may be detected based on the detection result of a sensor that detects the water level in the inner pot 31. The amount of rice may be input from the operation unit 94.

  The display unit 93 and the operation unit 94 are integrally configured as shown in FIG. The display operation by the display unit 93 is controlled by the display control unit 931 based on an instruction from the CPU 81. The display unit 93 displays information 931, 932, 933, and time information 934 for selecting a rice cooking course. Information 931 is information for selectively specifying whether or not the sheet 52 (catcher 51) is used, and information 932 is information for selectively specifying the heating procedure by the heater 12, such as white rice and high-speed rice cooking. The heating procedures for rice porridge and brown rice are shown. Information 933 is information for selectively designating the degree of rubbing (strong / weak / none) by stirring of the stirring blade 136.

  The operation unit 94 includes a heat retention / cancellation button 941, a reservation button 942 that is operated when setting the reserved rice cooking, a start button 943 that is operated when starting the cooking or determining the reserved rice cooking, and the display unit 93 It has a selection button 945 operated to select information and a course button 946 operated when selecting a rice cooking course. The heat retention / cancellation button 941 and the start button 943 have built-in lamps, and the lamps are turned on / off according to button operations.

  The heat retention / cancellation button 941 is operated to instruct the start of heat retention or cancel the heat retention state. When the warming process is started after cooking, the lamp of the warming / cancellation button 941 is turned on.

  The reservation button 942 is operated when setting reservation rice cooking. In conjunction with the operation of the reservation button 942, the reserved time is displayed as time information 934 on the screen of the display unit 93. Reservations can be made up to 12 hours later. The reservation time refers to the time for completing cooking. At the time of rice cooking, the remaining time until the end of rice cooking is displayed by the time information 934 based on the timing data of the timer 83.

  The course button 946 is used when selecting a rice cooking course. When the button is pressed once, the button corresponding to the white rice course among the buttons 947 adjacent to the information 932 is lit. Press again to light up the high speed course button. Each time the button is pressed in sequence, the course selection can be repeated, such as rice porridge of information 932 → brown rice → white rice. Each time a course is selected, a button corresponding to the course in the button 947 is lit.

  When the white rice course is selected, the white rice course lamp lights up. A rice cooking course can be selected by operating the selection button 945.

  The presence / absence (presence / absence) of the sheet 52 can be selectively set by the information 931. By default, “none” of the information 931 is selected. When selected, the characters of the information 931 are switched to bold display. In FIG. 4, it is instructed that “Yes” is selected. The selection of presence / absence of the sheet 52 of the information 931 can be switched by operating the selection button 945. “Used” is selected when the sheet 52 or the catcher 51 is used during cooking.

  Information 933 indicates the finished state of cooked rice, that is, the degree (strength) of rubbing between the rice grains in three types: [(strong) / (weak) / none]. The user can select from three types. The character indicating the selected degree of rubbing is switched to a thick character. If “None” is selected, no rubbing is performed. By default, (Weak) is selected. Selection of the degree of rubbing of the information 933 can be switched by operating a selection button 945. When the brown rice course of information 932 is selected, the degree of rubbing of information 933 cannot be selected. In FIG. 4, “strong” is selected.

  Even when each of the high-speed rice cooking course and the rice porridge course shown in the information 932 is selected, the finished state can be selected similarly to the white rice course.

  In the present embodiment, the CPU 81 detects the button operation content of the operation unit 94, and the presence / absence of the catcher 51 or the sheet 52 of the information 931 to 933, the heating procedure, and the degree of rubbing are selected based on the detected operation content. When determined, the rice cooking course selected based on the operation content is detected.

  With reference to FIG. 5, the attachment state of the rotation part 14 is demonstrated. In FIG. 5, a concave portion and a shaft (corresponding to the rotational shaft 134 in FIG. 6) are formed in advance in the central portion of the bottom surface of the inner pot 31 so as to match the shape of the rotating portion 14. It has a shape that can be fitted in. When the inner pot 31 is fitted, the rotating shaft 134 is connected to the central axis of the stirring blade 136.

  A motor unit 15 is attached to a position corresponding to the concave portion of the inner pot 31 outside the bottom surface of the outer pot 32. When the inner pot 31 to which the rotating unit 14 is attached is accommodated in the outer pot 32 (not shown), a driving force for rotation can be transmitted from the motor unit 15 to the rotating unit 14. Since the agitating blade 136 is detachably attached to the rotating portion 14, after use, the rotating portion 14 can be detached from the motor portion 15 or the agitating blade 136 can be detached from the rotating portion 14 and cleaned.

  A mechanism for rotating the stirring blade 136 will be described with reference to FIG. As a mechanism for rotation, a magnetic coupling type non-contact type stirring mechanism is employed in the present embodiment. Specifically, the motor unit 15 provided outside the bottom surface of the outer pan 32 has a stirring motor 131 and an outer box 138 connected to the rotating shaft of the stirring motor 131.

  The outer box 138 is a hollow box having a concave shape capable of receiving the rotating portion 14 and having an outer yoke 132 attached to the inner wall thereof. An outer magnet 133 is disposed on the inner wall of the outer box 138 to form a magnetic field with the outer yoke 132 interposed therebetween.

  When the inner pot 31 is accommodated in the outer pot 32, the rotating portion 14 of the inner pot 31 is attached so as to be fitted into the concave portion of the outer box 138. The rotating part 14 is coated with Teflon (registered trademark), which is a fluororesin, and the inside is filled and completely waterproof. The rotating unit 14 includes an inner yoke 137 that is disposed around the rotating shaft 134 of the inner pot 31 via a gap, and an inner magnet 135 that is disposed in the inner yoke 137 to form a magnetic field. The inner magnet 135 and the outer magnet 133 are positioned so as to face each other through a gap and are attracted to each other by a magnetic force.

  The stirring blade 136 is a substantially circular member made of a resin material (the diameter of the circle is about 5 to 7 cm), and a cross-shaped convex portion is formed so as to be orthogonal to the center of the circle. The convex portion has a mountain shape so that a water flow is easily generated by rotation.

  In operation, when the stirring motor 131 rotates, the outer box 138 connected to the motor shaft rotates, the outer magnet 133 rotates, and the inner magnet 135 attracted to the outer magnet 133 by magnetic force also rotates. As a result, the rotating part 14 itself rotates, and the stirring blade 136 interlocks and rotates within the bottom surface of the inner pot 31.

(Rotating speed of stirring blade 136)
According to the experiments by the inventors, in order to avoid the rice itself from being cracked or excessively scraped off by rubbing using the stirring blade 136 in the rice cooking process, the rotation speed of the stirring blade 136, that is, the stirring motor The knowledge that the rotational speed of 131 should be changed according to the quantity of the rice accommodated in the inner pot 31 was obtained. According to the experiment, when cooking 1 to 3 rice in a 5.5-cooked inner pot 31 (the inner diameter is about 19 cm uniformly in the depth direction and the depth is about 11 cm), the rotation speed Is 500 rpm (number of revolutions / minute), and in the case of 5 go, it is preferably 750 rpm.

According to the inventors' experiment, it was found that the operation of the stirring motor 131 during the rubbing period, that is, the rotation of the stirring blade 136 may be continuous or intermittent. As an operation rate per unit time (10 seconds), for example, when the operation rate is 20% in the case of intermittent operation of 2 seconds of operation and 8 seconds of stop, according to the experiment, the lipid oxide layer on the surface of the rice grain is formed by rubbing. In order to scrape off, it was found that the operation rate is preferably 36% to 100%. Moreover, if it was at least 36%, the knowledge that the water temperature in the inner pot 31 was uniformed was also obtained.
(About general rice cooking process)
A general rice cooking process will be described with reference to FIG. In the graph of FIG. 7 (A), the change of the water temperature in the inner pot 31 is shown. The vertical axis of the graph represents the water temperature (° C.), and the horizontal axis represents the elapsed time (minutes) from the start of cooking. This graph illustrates the process of containing 3 rice grains in the inner pot 31 and cooking in a rice cooker cooked at 5.5 go (1 go for rice is 150 grams).

  In general, the rice cooking process proceeds in the order of a water absorption / gelatinization process in which heating is performed by the heater 12, a boiling duration process, and a steaming process, following an immersion process in which heating by the heater 12 is not performed as shown in the graph. In the dipping process and the water absorption / gelatinization process, water is sufficiently absorbed into the core of the rice in order to gelatinize the starch of the rice. Cooking rice is to change the shape of raw starch by applying heat to water and rice, and to change to pregelatinized starch that is easy to digest. This change from raw starch to pregelatinized starch is called gelatinization. In gelatinization, it is known that when water and heat are added to starch of rice, a phenomenon of changing into a paste is observed, and gelatinization is started at a water temperature of 60 ° C.

  In operation, first, the user operates an open / close button (not shown) related to the mechanism 2A to take out the inner pot 31 from the main body 1 of the rice cooker.

  Weigh the amount of rice you want to cook. The unit of rice is goo and koji. 1 go is equivalent to 150 grams and 1 kaki is equivalent to 1500 grams. Since the rice after milling used at home still has a straw layer on the surface, the user first rinses (sharps) the rice with tap water. Washing rice uses a method of quickly stirring several times while exchanging water in order to remove the surface rust layer. The rice after washing and a predetermined amount of water (the amount of water added is 1.4 to 1.5 times the weight of the rice) are put into the inner pot 31. At this time, the rotating part 14 including the stirring blade 136 is attached to the bottom of the inner pot 31 in advance, and the contents (rice or water) do not leak from the bottom.

The inner pot 31 containing rice and water is set in the outer pot 32 of the main body 1 and the lid 2 is closed.
When the user presses start button 943, the rice cooking process is started. At this time, since the user operates the operation unit 94 to select the cooking course, the CPU 81 reads the control program PR corresponding to the course from the memory 82 according to the selection. Thereafter, the CPU 81 controls each unit based on the instruction code of the read control program PR. Thereby, cooking rice advances.

  In the rice cooking process, the heater control unit 76 outputs a control signal to the heater driving unit 92, so that the heater driving unit 92 energizes the heater 12 based on the control signal. Thereby, the contents of the inner pot 31 are heated. Simultaneously with the start of the rice cooking process, the CPU 81 inputs the temperature measured by the temperature sensor 9 and detects the water temperature in the inner pot 31 based on the input temperature. Thereby, temperature control in a rice cooking process is performed.

  According to FIG. 7 (A), the water | moisture content which rice contains becomes nearly 30% by immersing about 15 minutes at the water temperature of room temperature (20 degreeC), and an immersion process is complete | finished. Thereafter, while heating is started and the water temperature is raised, further water absorption and gelatinization of the rice is performed at 60 ° C. or higher.

  In the case of hunting at a certain constant temperature during heating, the heater controller 76 controls the energization amount of the heater 12 based on the temperature detected by the temperature sensor 9 so that the constant temperature can be maintained.

  After the water reaches 100 ° C., the heater control unit 76 controls the energization amount of the heater 12 via the heater driving unit 92 so that the boiling can be continued for 15 minutes or more.

  The steam in the inner pot 31 that has become extra during boiling is exhausted to the outside through a small hole (not shown) of the lid 2 and the steam cylinder 5 as necessary. After boiling for 15 minutes, there is almost no free water in the inner pot 31, and the rice has been fully alphalated into rice. After that, the process goes to the steaming process.

  In the steaming process, the heater control unit 76 controls the heater 12 so that the temperature does not become 95 ° C. or lower. The rice balls that remain slightly on the surface of the rice at this stage are absorbed into the rice, so it changes to a delicious and shiny rice. When the steaming process is completed, the cooking of rice is completed (the end of the cooking process).

  Thus, the temperature control is performed according to the purpose of the gelatinization process in which starch is eluted from rice, the subsequent boiling duration process, and the steaming process. The water absorption process after the dipping process is that the water temperature is from room temperature to 60 ° C., the gelatinization process is at a water temperature of 60 ° C. or more to 100 ° C., the boiling continuous process is maintenance at 98 ° C. or more for 20 minutes or more, and the steaming process is 95 ° C. or more. Maintenance is 15 minutes or more.

  In FIG. 7A, it is possible to hunt the temperature around 55 ° C. in the water absorption / gelatinization step so as to maintain a certain temperature. In this case, the effect of increasing the enzyme activity of rice and promoting the production of sugar can be obtained.

  Although not shown in the graph, when the rice cooking process is started, the water absorption / gelatinization process is started without going through the dipping process, and immediately after the water absorption / gelatinization process, the temperature is increased to the boiling duration process at once. May be. In this case, the elasticity of the rice is increased. In this case as well, the stirring operation is performed below the gelatinization temperature.

(Basic timing of rubbing in the rice cooking process)
As shown in FIGS. 7B and 7C, it is desirable to change the rubbing timing according to the state of rice. For example, in the case of old rice that has been stored for more than one year, as shown in FIG. 7 (B), the entire period of the dipping process and the water absorption / gelatinization process (however, the period below the gelatinization start temperature) is the rubbing period Thus, the oxidized lipid layer can be sufficiently removed, and the taste can be brought close to that of the new rice. In particular, rice that has been preserved in the summer from the rainy season has an increased lipid oxide layer every day at home, so that the taste can be improved by rubbing during the period of FIG. 7B. On the other hand, in the case of new rice, since the lipid oxide layer is hardly included, it is possible to avoid excessively shaving the surface of the rice grain by rubbing only in the dipping process as shown in FIG.

(Timing of rubbing with cooking course)
The graphs of FIGS. 8 to 11 show the change in water temperature and the timing of rubbing between the rice for each rice cooking course of the present embodiment. The vertical axis of the graph represents the water temperature (° C.) and the operation rate (%) of rubbing, and the horizontal axis represents the elapsed time (minutes) from the start of cooking. This graph exemplifies the process of storing 3 go white rice in the inner pot 31 and cooking on the white rice course in a cooker cooked at 5.5 go (1 go for rice is 150 grams). The changes in the water temperature shown in these graphs coincide with those in the graph shown in FIG.

  A broken line graph indicates a change in water temperature, and a solid line graph indicates an operation rate of the stirring motor 131. During the period when the operation rate indicates 0%, the stirring motor 131 is stopped and there is no rubbing. During the period when the operation rate indicates a value of 36% to 100%, the stirring motor 131 is driven and the rice grains are driven. This refers to the state in which they are rubbed together. In any rice cooking course, rubbing of rice grains by stirring is performed at a gelatinization start temperature (60 ° C.) or lower.

  The rice cooking course of FIG. 8 and FIG. 9 is a pattern in which a user replaces immersion water. Specifically, the rice cooking courses in FIGS. 8 and 9 are cases where the user operates the operation unit 94 to select “none” for the sheet 52 and the catcher 51, and in FIG. In FIG. 9, the rubbing strength is selected as “strong”.

  In the “sheet (none) + rubbing (weak)” rice cooking course of FIG. 8, the stirring motor 131 is started to operate at an operation rate of 36% as the rice cooking process starts, and the stirring operation is performed. When a predetermined period elapses after the operation is started, the operation is temporarily stopped, the buzzer 90 sounds and the water change timing is notified. When the notification is made, the user takes out the inner pot 31, discharges the immersion water, and puts new water (water temperature 20 ° C.) in an amount that reaches a predetermined scale line printed in advance on the inner peripheral surface of the inner pot 31. Then, the inner pot 31 is set in the rice cooker, and the lid 2 is closed. In addition, the graduation line which supports the quantity of the water which should be added for every quantity of the rice to cook is printed in advance on the internal peripheral surface of the inner pot 31. When the opening / closing sensor 91 detects that the lid 2 is closed, the stirring operation that has been temporarily stopped is resumed.

  In the “sheet (none) + rubbing (strong)” rice cooking course of FIG. 9, the stirring motor 131 is started to operate at an operation rate of 100% as the rice cooking process starts, and the stirring operation is performed. Subsequent operations are the same as those in FIG. After the water is replaced, the stirring operation is resumed at an operation rate of 36%.

  Since the immersion water is replaced as described above, the lipid oxide component scraped off from the surface of the rice grain by the stirring operation and transferred to the water side can be discharged.

  The rice cooking course of FIG. 10 and FIG. 11 is a pattern which can abbreviate | omit the replacement | exchange of immersion water by the above users by using the catcher 51 or the sheet | seat 52. FIG. Specifically, in the rice cooking course of FIGS. 10 and 11, the user operates the operation unit 94 to select “Yes” for the sheet 52 and the catcher 51. In FIG. "Is selected, and in FIG. 11, the rubbing strength is selected as" weak ".

  In the “sheet (present) + rubbing (strong)” rice cooking course of FIG. 10, the stirring motor 131 is started to operate at an operation rate of 50% as the rice cooking process starts, and the stirring operation is performed. The operation rate is switched from 50% to 36% when a predetermined period elapses after the operation is started, and then the stirring operation is continued in a period below the gelatinization temperature.

  In the rice cooking course of “sheet (present) + rubbing (weak)” in FIG. 11, the stirring motor 131 is started at a driving rate of 36% at the start of the rice cooking process, and the operation is continued during the period when the water temperature is equal to or lower than the gelatinization temperature. To do.

  Thus, based on the information specifying the strength of rubbing indicated by the rice cooking course information 193, the operation rate at which the stirring blade 136 stirs the contents of the inner pot 31 in the rice cooking process, that is, the total number of times is controlled variably. Is done.

(Flowchart of rice cooking process)
The process flowchart of the rice cooking process is stored in the memory 82 as the control program PR in advance according to the rice cooking course. Which control program PR is used to execute the rice cooking process is determined based on the content of the user operating the operation unit 94 in the preprocessing.

  In the pretreatment, the user sets the inner pot 31 containing a predetermined amount of rice and water in the outer pot 32 of the main body 1, closes the lid 2, and then operates the operation unit 94 to start cooking. Select a course. The course determination unit 71 detects the operation content of the operation unit 94, and determines the rice cooking course based on the detected operation content. The determined rice cooking course is given to the control procedure determination unit 72. The above is the preprocessing. Thereafter, the user operates the start button 943 to instruct the start of the rice cooking process.

  Hereinafter, the processing procedure of the rice cooking process will be described for each rice cooking course. Here, it is assumed that a procedure corresponding to white rice is selected as the heating procedure based on information 932.

<Sheet (none) + Rub (weak) course>
A rice cooking process when “sheet (none) + rubbing (weak) course” is selected as the rice cooking course will be described with reference to the flowcharts of FIGS.

  When it is detected that the start button 943 has been operated (step S (hereinafter simply referred to as S) 101), the control procedure determination unit 72 generates a control program PR corresponding to the rice cooking course information given in the preprocessing. The data is retrieved from the memory 84 and read (S102). Thereafter, the CPU 81 executes the instruction code of the read control program PR and controls each part, whereby a rice cooking process corresponding to the selected rice cooking course is performed.

  First, the rice quantity determination unit 73 detects the amount of rice stored in the inner pot 31 based on the detection data of the weight sensor 97, and provides the detected rice quantity data to the rotation speed determination unit 74. The rotational speed determination unit 74 determines the rotational speed of the stirring blade 136 based on the given rice amount data, and outputs it to the motor control unit 75 (S103). Here, a table in which the rice amount and the rotation speed are associated with each other is stored in the memory 84 in advance, so that the corresponding rotation speed can be read by searching the table based on the detected rice amount data.

  The motor control unit 75 outputs a control signal based on the given rotation speed to the motor drive unit 95. The motor drive unit 95 energizes the stirring motor 131 based on the control signal. Thereby, the stirring motor 131 rotates at a speed corresponding to the amount of rice. The stirring blade 136 rotates in conjunction with the rotation of the motor, and the rubbing of the rice starts (S104a). The motor control unit 75 controls the stirring motor 131 to rotate at an operation rate of 36%.

  From here, the immersion process accompanied by the removal process of the oxidized lipid layer starts (S105a). When the dipping process is started, the timer 83 starts the dipping time and the removal time of the lipid oxide layer, that is, the time count of the stirring period (S106a). If the motor control unit 75 determines that the removal time of 5 minutes has elapsed based on the timing data from the timer 83 (YES in S107a), the motor control unit 75 outputs a control signal for stopping the stirring motor 131 to the motor driving unit 95. The motor drive unit 95 stops the rotation of the stirring motor 131 based on the control signal. Thereby, the stirring operation by the rotation of the stirring blade 136 is stopped, and the removal process of the lipid oxide layer by rubbing the rice is temporarily stopped (S108a).

  When the removal process is temporarily stopped, the notification unit 77 controls to sound the buzzer 90 (S109a). The ringing of the buzzer 90 is detected until it is detected that the user has taken out the inner pot 31 from the rice cooker for water change, that is, until the weight W1 detected by the weight sensor 97 indicates 0 (S110a, (YES in S111a) Continue. When it is detected that the weight W1 indicates 0, the CPU 81 starts blinking the lamp of the start button 943. The blinking is to prompt the user to operate the start button 943 and continues until it is detected that the user has operated.

  The user confirms that it is the timing of water change by ringing the buzzer 90, removes it from the inner pot 31 rice cooker, changes the immersion water, and then sets the inner pot 31 to the rice cooker again (S112a), The start button 943 is operated (S113a).

  When the operation of the start button 943 is detected (S113a), the motor control unit 75 outputs a control signal for causing the motor driving unit 95 to resume the rotation of the stirring motor 131. As a result, the agitation motor 131 resumes rotation at an operation rate of 36%, and the agitation blade 136 rotates in conjunction with the rotation (S114a). This rotation continues until the gelatinization start temperature (60 ° C.) is detected (S126a, S127).

  When the rotation is resumed, if the heater control unit 76 determines that the remaining time T3 of the immersion process has elapsed 15 minutes based on the time measurement data from the timer 83 (S116, S117a), the heater 12 via the heater driving unit 92. Is energized (S118a). Thereby, the heating of the contents (rice and water) of the inner pot 31 is started.

  When heating is started, the water absorption / gelatinization process is started (S119a). Next, the heater control unit 76 measures the pot bottom wall surface temperature K1 of the inner pot 31 based on the temperature detected by the temperature sensor 9 (S120a). Here, it is assumed that the pot bottom wall surface temperature K1 is equal to the water temperature of the inner pot 31.

  When the heater control unit 76 detects that the pan bottom wall surface temperature K1 indicates a predetermined temperature, for example, 55 ° C. (YES in S121a), the heater 12 is connected via the heater driving unit 92 so that the temperature detected by the temperature sensor 9 is maintained at the predetermined temperature. The energization amount is controlled (S122a).

  The motor control unit 75 starts measuring the water absorption time T3 based on the timing data of the timer 83 (S123a). Next, the pan bottom wall surface temperature K2 is measured based on the temperature detected by the temperature sensor 9 (S124a). When it is determined that the set water absorption time T2 (= 15 minutes) has elapsed (S125a) and it is determined that the pan bottom wall surface temperature K2 indicates 60 ° C. or higher based on the temperature detected by the temperature sensor 9 (S126a), gelatinization is performed. Is started, a control signal for stopping the agitation motor 131 is output to the motor drive unit 95. The motor drive unit 95 stops the rotation of the stirring motor 131 based on the control signal. Thereby, the stirring operation by the rotation of the stirring blade 136 is stopped, and the rice rubbing is finished (S127a).

  After that, in order to boil the inside of the inner pot 31, the heater control unit 76 energizes the heater 12 through the heater driving unit 95 so that heating is performed at full power (S128 in FIG. 13). Based on the temperature detected by the temperature sensor 9, the bottom wall temperature K3 of the inner pot 31 is measured (S129). When boiling and evaporation in the inner pot 31 due to continuous heating of the heater 12 continues for a while (boiling duration process), the state changes to a state where there is almost no water at the bottom of the inner pot 31.

  When the heater control unit 76 detects that the pan bottom wall surface temperature K3 indicates 103 ° C. or higher based on the temperature detected by the temperature sensor 9 (YES in S130), the heater control unit 76 stops energizing the heater 12 via the heater driving unit 92. To do. Thereby, the heating operation with respect to the inner pot 31 is stopped (S131).

  Then, it shifts to the steaming process. After stopping the heating operation (ending the boiling continuous process), the CPU 81 starts measuring the steaming time T4 based on the time data of the timer 83 in order to steam the cooked rice in the inner pot 31 (S132). Also in the steaming step, the pan bottom wall surface temperature K4 is detected based on the temperature detected by the temperature sensor 9 (S133). In the steaming process, the heater control unit 76 compares the pan bottom wall temperature K4 based on the temperature detected by the temperature sensor 9 with 95 ° C, and based on the comparison result, the heater bottom wall temperature K4 does not fall below 95 ° C. The energization amount of the heater 12 is controlled via the drive unit 92 to control the heating amount (S133 to S135).

  The CPU 81 determines whether or not the steaming time T4 indicates 15 minutes or more based on the timing data of the timer 83 (S136). If it determines with the steaming time T4 having passed for 15 minutes (it is YES at S136), a rice cooking process will be complete | finished (S137). At the end of the rice cooking process, the CPU 81 may output a sound or a message notifying the end of rice cooking via an audio output unit such as the buzzer 90.

  The heater control unit 76 controls the energization amount of the heater 12 via the heater driving unit 92 so as to proceed to the heat retaining process, and operates to heat the cooked rice in the inner pot 31 (S138). The CPU 81 lights the lamp of the heat retention / cancellation button 941 during the heat retention process to notify that it is in the heat retention state. In addition, at the start of heat retention, the fan 7 is rotated via the fan drive unit 96 to rapidly cool and suppress the oxidation of the cooked rice.

  As described above, in the sheet (none) + rubbing (weak) course, stirring by the stirring blade 136 is performed while the water is changed during the period from the start of the rice cooking process until the water temperature in the inner pot 31 reaches the gelatinization start temperature. It is carried out intermittently at an operation rate of 36%.

<Sheet (None) + Rub (Strong) Course>
A rice cooking process when “sheet (none) + rubbing (strong) course” is selected as the rice cooking course will be described with reference to the flowcharts of FIGS.

  When the CPU 81 detects that the start button 943 has been operated, the same processing as S101 to 103 in FIG. 12 is performed. That is, the rice cooking process according to the selected rice cooking course is performed by executing the command code of the control program PR corresponding to the rice cooking course determined in the pre-processing and controlling each part.

  The processing of S118a to S138 is the same as the corresponding processing of FIGS.

  Since the motor control unit 75 outputs a control signal based on the given number of rotations to the motor driving unit 95, the stirring motor 131 rotates at a speed corresponding to the amount of rice, and the stirring blade 136 is interlocked with the rotation of the motor. Rotates and the rubbing of the rice starts (S204b). The motor control unit 75 controls the stirring motor 131 to rotate at a driving rate of 100%, that is, continuously.

  From here, the immersion process accompanied by the removal process of the oxidized lipid layer starts (S205b). When the dipping process is started and the motor control unit 75 determines that the removal time of 7 minutes has elapsed based on the timing data from the timer 83 (YES in S206b and 207b), it outputs a stop control signal to the motor drive unit 95. Therefore, the stirring motor 131 stops rotating (S208b). Thereby, the stirring operation by the rotation of the stirring blade 136 is stopped, and the removal process of the lipid oxide layer by rubbing the rice is temporarily stopped (S208b).

  When the removal process is temporarily stopped, the notification unit 77 sounds the buzzer 90 to notify the timing of water change (S209b). The user confirms the ringing of the buzzer 90, takes out the inner pot 31 from the rice cooker, replaces the immersion water, sets the inner pot 31 in the rice cooker again (S210b, S211b, S212b), and presses the start button 943. Operate (S213b).

  When the operation of the start button 943 is detected, the motor control unit 75 outputs a control signal for causing the motor driving unit 95 to restart the rotation of the stirring motor 131. As a result, the agitation motor 131 resumes rotation at an operation rate of 36%, and the agitation blade 136 rotates in conjunction with the rotation (S214b). This rotation continues until the gelatinization start temperature (60 ° C.) is detected (S126a, S127a).

  When the rotation is resumed, if the heater control unit 76 determines that the remaining time T2 of the dipping process has elapsed 15 minutes (S216b, S217b), the heater 12 starts energization via the heater driving unit 92. Heating of the contents (rice and water) of the pan 31 is started (S118a).

  When heating is started, the water absorption / gelatinization process is started (S119a). Hereinafter, the process up to the start of the heat retaining process is the same as described above.

  In this way, the sheet (none) + rubbing (strong) course makes it easier to scrape the surface of the rice grains because the rice is rubbed together at an operation rate of 100%. After purchasing the oxidized lipid layer (after milling), for example It is desirable to be applied when the surface lipid oxidation is relatively advanced, such as rice stored at room temperature for 1 month or more, or rice that has been placed in a high temperature room temperature atmosphere in summer for 1 week or more.

<Sheet (Yes) + Rub (Strong) Course>
A rice cooking process when “sheet (present) + rubbing (strong) course” is selected as the rice cooking course will be described with reference to the flowcharts of FIGS.

  When the CPU 81 detects that the start button 943 has been operated, the same processing as S101 to 103 in FIG. 12 is performed. That is, the rice cooking process according to the selected rice cooking course is performed by executing the command code of the control program PR corresponding to the rice cooking course determined in the pre-processing and controlling each part.

  The processing of S118a to S138 is the same as the corresponding processing of FIGS.

  Since the motor control unit 75 outputs a control signal based on the given number of rotations to the motor driving unit 95, the stirring motor 131 rotates at a speed corresponding to the amount of rice, and the stirring blade 136 is interlocked with the rotation of the motor. Rotates and the rubbing of the rice starts (S304c). The motor control unit 75 controls the stirring motor 131 to rotate at an operation rate of 50%, that is, intermittently.

  From here, the immersion process accompanied by the removal process of the lipid oxide layer starts (S305c). When the dipping process is started and the motor control unit 75 determines that the removal time of 15 minutes has elapsed based on the timing data from the timer 83 (YES in S306c and 307c), the operation rate is changed. Since the motor control unit 75 outputs a control signal with an operation rate of 36% to the motor drive unit 95, the rotation of the stirring motor 131 is changed to an operation rate of 36% (S309c). The rotation of the stirring motor 131 at the operation rate of 36% is continued until the gelatinization start temperature (60 ° C.) is detected (S126a, S127a).

  When the heater control unit 76 determines that the remaining time T2 of the dipping process has elapsed 5 minutes after the operation rate is changed to 36% (S310c, S311c), the heater 12 starts energization via the heater driving unit 92. Therefore, heating of the contents (rice and water) of the inner pot 31 is started (S118a). When heating is started, the water absorption / gelatinization process is started (S119a). The subsequent processing up to the start of the heat retaining process is the same as described above.

<Sheet (with) + Rub (weak) course>
A rice cooking process when “sheet (present) + rubbed (weak) course” is selected as the rice cooking course will be described with reference to the flowchart of FIG.

  When the CPU 81 detects that the start button 943 has been operated, the same processing as S101 to 103 in FIG. 12 is performed. That is, the rice cooking process according to the selected rice cooking course is performed by executing the command code of the control program PR corresponding to the rice cooking course determined in the pre-processing and controlling each part.

  The processing of S118a to S138 is the same as the corresponding processing of FIGS.

  Since the motor control unit 75 outputs a control signal based on the given number of rotations to the motor driving unit 95, the stirring motor 131 rotates at a speed corresponding to the amount of rice, and the stirring blade 136 is interlocked with the rotation of the motor. Rotates and the rubbing of the rice starts (S404d). The motor control unit 75 controls the stirring motor 131 to rotate at an operation rate of 36%, that is, intermittently.

  From here, the immersion process accompanied by the removal process of the oxidized lipid layer starts (S405d). When the dipping process is started and the heater control unit 76 determines that the removal time (immersion time) of 20 minutes has elapsed based on the time measurement data from the timer 83 (YES in S406d and 407d), the heater control unit 76 performs heating via the heater driving unit 92. Since energization is started at 12, heating of the contents (rice and water) of the inner pot 31 is started (S 118 a). When heating is started, the water absorption / gelatinization process is started (S119a). The subsequent processing up to the start of the heat retaining process is the same as described above.

  Since the sheet (present) + rubbing (weak) course shown in this flowchart is an intermittent stirring operation with an operation rate of 36%, the total number of stirring (in comparison with the sheet (present) + rubbing (strong) course ( Since the number of revolutions of the stirring blade 136 is small, when it is desired to reduce the amount of the surface layer that is scraped off when the rice grains are rubbed with each other, it is preferably applied to, for example, the cooking of new rice.

<Rubbing (none) course>
A rice cooking process when “rubbed (none) course” is selected as the rice cooking course will be described with reference to the flowchart of FIG. 19.

  When the CPU 81 detects that the start button 943 has been operated, processing similar to S101 to S102 in FIG. 12 is performed. That is, the rice cooking process according to the selected rice cooking course is performed by executing the command code of the control program PR corresponding to the rice cooking course determined in the pre-processing and controlling each part.

  The processing of S118a to S138 is the same as the corresponding processing of FIGS. First, when the heater control unit 76 determines that the immersion time of 20 minutes has elapsed based on the time measurement data from the timer 83 (YES in S504e, S505e, and S506e), the heater 12 starts energization via the heater driving unit 92. The heating of the contents (rice and water) of the inner pot 31 is started (S118a). When heating is started, the water absorption / gelatinization process is started (S119a). The processing up to the start of the heat retention process for the transfer is the same as described above.

  The rice cooking course without rubbing is applied to, for example, cooked rice with a large amount of oil such as cooked rice of chicken, cooked rice mixed with small ingredients such as sesame. Since stirring is omitted, the ingredients can be prevented from being separated.

(Other configuration examples of the stirring unit)
In the above-described embodiment, the stirring blade 136 is provided so as to rotate in the same plane as the bottom surface of the inner pot 31, but the configuration and mounting mode of the stirring member are not limited to this.

  FIG. 20 shows a configuration of a stirring member according to another embodiment. Referring to FIG. 20, the stirring member is integrally attached to lid 2. The stirring member includes a stirring motor 131 built in the lid 2, a propeller-type stirring blade 139 connected to the motor shaft of the stirring motor 131, and a shaft (connected to the motor shaft) that holds the propeller-type stirring blade 139. A case 138 for housing the shaft). The shaft that holds the stirring blade 139 at the tip is connected to the motor shaft of the stirring motor 131 and is extendable.

  The case 138 is accommodated by extending or contracting a shaft that holds the propeller-type stirring blade 139 or is extended toward the bottom surface of the inner pot 31. When the lid 2 is opened and closed by the user, the shaft is housed in the case 138.

  When the lid 2 is closed and the rice cooking process is started, only in the stirring period shown in FIGS. 8 to 10, the shaft holding the stirring blade 139 extends from the case 138 toward the bottom surface of the inner pot 31, and the propeller type stirring is performed. The wing 139 is located in the immersed rice and rotates. During other periods, the shaft is housed in the case 138.

  During the agitation period, the agitation motor 131 rotates at the number of revolutions corresponding to the amount of rice as described above. Since the propeller-type stirring blade 139 rotates in conjunction with the rotation of the motor, a water flow is generated in the inner pot 31, and the rice moves in the water and is rubbed with it. Thereby, the effect of rubbing is acquired similarly to the case where the stirring blade 136 provided in the bottom face of the inner pot 31 is used.

  In addition, when using the sheet | seat 52 and the catcher 51, the stirring member shown in FIG. 5 and FIG. 6 is used instead of the stirring member of FIG.

  Although the stirring part mentioned above was the structure which a wing | blade rotates in the immersed rice, you may make it the inner pot 31 itself rotate. Specifically, a motor is connected to the turntable via a shaft, and the inner pot 31 is placed on the turntable. In operation, when the motor is driven to rotate, the rotating table rotates through the shaft, and the inner pot 31 placed on the rotating table rotates. Thereby, in the inner pot 31, rice and water are stirred while flowing.

(Composition of sheet and catcher)
FIG. 21 is a schematic view of the sheet 52, and FIG. 22 is a schematic view of the catcher 51. The sheet 52 is a thin film made of a nonwoven fabric excellent in the function of adsorbing oil components, has a substantially circular shape, and the diameter thereof is cut according to the inner diameter of the inner pot 31. Small holes are formed in some places of the sheet 52. At the time of the rice cooking process, the sheet 52 is on the water surface of the inner pot 31, so that the lower water overflows to the upper part of the sheet 52 through the small holes. Fatty acids, which are unnecessary components contained in the overflowing water, are effectively adsorbed on the surface of the sheet 52 or absorbed between the layers of the sheet 52.

  The catcher 51 of FIG. 22 has a plastic plate-like circular shape, and has a diameter that matches the inner diameter of the inner pot 31. Small holes are formed in the catcher 51 in advance. In use, it is placed on the rice in the inner pot 31. A plurality of elongated protrusions are formed on the upper surface opposite to the rice in the mounted state. By the protrusion, unnecessary components in the water overflowing to the upper portion of the catcher 51 through the small holes can be collected and separated on the upper surface of the catcher 51.

  These are placed on top of water and rice at the start of the rice cooking process, so that the sheet 52 adsorbs and separates the oxidized lipid component separated by rubbing the rice together in the water, and the catcher 51 Is separated at the top of the catcher 51. Since free fatty acids are not easily dissolved in water, they are distributed on the surface of the aqueous layer when scraped from the rice grains by rubbing, and can be recovered by the sheet 52 and the catcher 51 when they gradually boil up in the boiling process.

  After putting the washed rice and water into the inner pot 31, the sheet 52 may be placed so that it floats on the water, the catcher 51 may be placed on the rice, and free fatty acids can be removed without trouble. it can.

  In the present embodiment, the sheet 52 and the catcher 51 are used in combination in order to remove the free fatty acid more reliably, but the free fatty acid can be removed by using only one of them.

(Results of fatty acid content measurement test)
FIG. 23 shows the value of the fatty acid degree remaining in the cooked rice after cooking. The degree of fatty acid is expressed by the amount of KOH (potassium hydroxide) required for neutralization of the amount of free fatty acid extracted from rice or rice, and is an index that is evaluated as being old rice as the amount increases.

  Inventors obtained the measurement result of the fatty acid degree of FIG. 23 by the test. Specifically, the water content was measured after rubbing the rice in water during the rice cooking process in this embodiment, and the fatty acid degree of the rice itself measured using Kinuhikari from Shiga Prefecture in 2007 as the sample rice. Then, the fatty acid degree of cooked rice is shown. “Low-temperature stirring rice” in the graph refers to the case where the water temperature corresponding to the dipping process is cooked by rubbing at a predetermined operation rate in the period up to 20 ° C. (low-temperature region). In addition, it refers to the case where the rice is cooked by rubbing at a predetermined operation rate in a period corresponding to the water absorption / gelatinization step (60 ° C. or less). The test was conducted in June 2009.

  Rice used for the test is classified as old rice. In this measurement test, the sample was measured after freeze-drying in order to remove water from the rice. The time required for lyophilization is several days. Since free fatty acids may volatilize during lyophilization, rice is lyophilized and measured in the same way. Conventionally, in the case of old rice, 20 mgKOH / 100 gd. w (the amount of KOH required to neutralize rice per 100g dry weight is 20mg), but this freeze-drying has reduced the fatty acid content of rice to about 1/5. . The rubbed rice may also have a recovery rate of about 1/5, but as shown in the measurement results of FIG. 23, compared to the residual fatty acid degree of the rice itself, In the case of ', about 90% of the fatty acid was removed, and in the case of' medium temperature stirring rice ', about 60% of the fatty acid was removed although there was reabsorption as the water temperature increased.

  From the test results, the inventors can increase the amount of the oxidized fat layer that can be scraped off from the surface of the rice grains as the number of stirrings increases, and the amount of the oxidized fat layer that can be scraped off as the number of stirring rotations decreases. Got the conclusion that there are few. The changes in the operation rate and operation period shown in FIGS. 8 to 11 depend on the test results.

(Result of taste test)
The inventors collected the cooked rice by the taste tester and collected taste evaluation data (evaluation items were appearance, taste, stickiness, hardness, and overall). The thick solid line in FIG. 24 indicates the taste result of the rice by the conventional rice cooking process, and the thin solid line indicates the taste evaluation of the rice by the rice cooking process with stirring (oxidation fat layer removal process) according to the present embodiment.

  Kinuhikari produced in Shiga Prefecture in 2008 is used as the sample rice. The thick solid line indicates the data of cooked rice according to the rice cooking process of Fig. 7 (A), and the thin solid line indicates the dipping process and the water absorption / gelatinization process (however, 60 ° C. or lower) refers to data of cooked rice that has been rubbed together at a predetermined operation rate and changed water after the dipping process. According to FIG. 24, compared to the case where the rice was cooked without rubbing, the rice with reduced odor by removing the oxidized fat layer by rubbing and changing the water was more delicious (flavored). ) Was confirmed to be effective.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 9 Temperature sensor, 12 Heater, 31 Inner pan, 32 Outer pan, 51 Catcher, 52 Sheet, 71 Course determination part, 72 Control procedure determination part, 73 Rice quantity determination part, 74 Rotation number determination part, 75 Motor control part, 76 Heater control unit, 93 display unit, 94 operation unit, 131 stirring motor, 136 stirring blade.

Claims (9)

A rice cooker that holds a pot containing water for immersing rice and rice, and controls the time and temperature for heating the held pot,
Heating means for heating the pan;
Temperature measuring means for measuring the temperature inside the pan; and
Rubbing means for rubbing rice grains soaked in water in the pan in the rice cooking process;
A rice cooker comprising: means for removing the surface layer portion of the rice grain that is scraped off from the rice grain by the rubbing and moves to the water side.   Control means for driving the heating means and the rubbing means using the information on the temperature measured by the temperature measuring means in response to inputting information on the start instruction of the rice cooking process is further provided. The rice cooker according to claim 1.   The period during which the rubbing means is driven is set within a period from the start of the rice cooking process until the measured temperature of the temperature measuring means rises due to heating and indicates the gelatinization start temperature of rice. 2. The rice cooker described in 2.   4. The rice cooker according to claim 1, wherein the removing means includes a sheet-like member having an oil adsorption function placed on a water surface in which rice in the pan is immersed.   The said means to remove contains the flat plate member in which the several hole which the said rice grain surface layer part which is mounted on the rice which the said pan soaked and passes through was formed was formed is in any one of Claim 1 to 4 The described rice cooker. A rice cooker that holds a pot containing water for immersing rice and rice and controls the time and temperature of heating the held pot,
Heating means for heating the pan;
Temperature measuring means for measuring the temperature inside the pan; and
Rubbing means for rubbing rice grains soaked in water in the pan in the rice cooking process;
In response to inputting the information of the start instruction of the rice cooking process, using the temperature information measured by the temperature measuring means, the control means for driving the heating means and the rubbing means,
A rice cooker comprising: an informing means for instructing to stop driving of the rubbing means and to replace the water in the pan.   The period during which the rubbing means is driven is set within a period from the start of the rice cooking process until the measured temperature of the temperature measuring means rises due to heating and indicates the gelatinization start temperature of rice. 6. The rice cooker according to 6. A method for controlling a rice cooker that holds a pot containing rice and water for immersing the rice and heats the held pot,
The rice cooker
Heating means for heating the pan;
Rubbing means for rubbing rice grains soaked in the water of the pan;
A means for removing the surface part of the rice grain that is scraped off from the rice grain by the rubbing and moves to the water side, and
The control method is:
Measuring the temperature inside the pan;
A method of controlling a rice cooker, comprising the step of driving the heating means and the rubbing means using information on the measured temperature in response to inputting information on a start instruction for the rice cooking process. A method for controlling a rice cooker that holds a pot containing rice and water for immersing the rice and heats the held pot,
The rice cooker
Heating means for heating the pan;
Rubbing means for rubbing rice grains immersed in the water of the pan, and
The control method is:
Measuring the temperature inside the pan;
In response to inputting information on the start instruction of the rice cooking process, using the measured temperature information, driving the heating means and the rubbing means,
A method of controlling the rice cooker, comprising: stopping the driving of the agitation means and informing the user to replace the water in the pan.

Images