JP6742097B2 - Method for determining water content of rice to be cooked, water content determination device, immersion time determination device, and rice cooking equipment - Google Patents

Description

The present invention relates to a method for determining a water content state of rice to be cooked, a water content state determination device, an immersion time determination device, and rice cooking equipment.

Rice is a staple food of Japanese people, and various techniques for evaluating the quality of rice have been developed.

In the white rice quality evaluation method of Patent Document 1, a load is applied to each rice grain of the white rice sample after immersion in water for a predetermined time, the load peak value obtained from each rice grain is totaled, and the cooked rice is cooked based on the totaled result. Predicts the hardness of.

In the quality evaluation method of cooked rice in Patent Document 2, the internal structure of cooked rice is nondestructively analyzed by nuclear magnetic resonance micro-imaging and a transmission image of X-ray or visible light to evaluate quality. Specifically, for the cooked rice grains, the area, size, and depth of the internal cavity are analyzed, and the results are evaluated.

JP, 2002-323418, A JP, 2000-065768, A

By the way, rice is cooked by washing, dipping, heating and steaming. A factor that greatly affects the taste of cooked rice (rice cooked rice) is the water content (moisture content) of rice, which is an important factor for gelatinization of rice starch. The water content of rice increases moment by moment during the process of soaking in water, and reaches saturation at some point. The time to reach saturation varies depending on the rice variety, production area, harvest time, dryness after harvesting, temperature during soaking, etc., and it is difficult to predict in advance. If the water content of rice, which changes moment by moment in the process of immersion in water, can be easily evaluated with time, rice can be cooked at an appropriate water content, and the taste of cooked rice can be improved.

Although the technique of the above-mentioned patent document 1 uses the peak value of the load applied to the rice grains for evaluation, the relationship with the water content state is unknown. Moreover, the fact that the peak value of the load is obtained means that the rice grains used for the evaluation should be destroyed or at least the state should be changed irreversibly. Therefore, it is not suitable for observing the state of rice over time, and it is not a simple technique.

Further, the technique of Patent Document 2 is intended for rice after cooking rice, and cannot evaluate the water content because it evaluates the internal structure. In addition, the device becomes large-scale and far from simple evaluation.

The present invention has been made in view of the above problems, and its purpose is to easily and accurately evaluate the water content of cooked rice to be immersed in water, and to improve the taste of cooked cooked rice. It is to provide the technology that can help.

The characteristic configuration of the method for determining the water content state of the rice to be cooked of the present invention for achieving the above-mentioned purpose is to irradiate visible light to the rice to be cooked to be immersed in water and optically observe the color of the rice to be cooked Based on the measurement step of measuring tint information regarding taste over time and the measured tint information, whether the water content of the rice to be cooked is saturated and the rice to be cooked is in a water-containing state suitable for cooking rice There rows and determination step of determining,
In the measuring step, the light from the rice to be cooked is dispersed, and the intensity of light obtained for each wavelength is used as the tint information .

The characteristic configuration of the water content determination device of the present invention for achieving the above object is to store rice to be cooked in rice, to immerse the rice in the water, and to irradiate visible light to the rice to be cooked in the measurement container. Then, the moisture content of the rice to be cooked is based on the color information measured by the measuring unit and the measuring unit for measuring the tint information regarding the tint of the rice to be cooked over time. saturated cooking target rice have a determining unit whether it is a water-containing state suitable for cooking and,
In the measuring unit, the light from the rice to be cooked is dispersed, and the intensity of the obtained light for each wavelength is used as the tint information .

While examining the evaluation method of the water content state of the rice to be cooked, the inventors have noticed that the color changes as the rice to be cooked absorbs water. The rice to be cooked in the experiment had a slightly yellow color before absorbing water, but when it absorbed water, it changed to a transparent white color. Then, the inventors experimentally confirmed that there is a strong correlation between the color information obtained by optically observing the rice to be cooked and the water content of the rice to be cooked, and thus the present invention was completed. It has arrived.
That is, according to the above-mentioned characteristic configuration, the rice to be cooked for cooking which has been immersed in water is optically observed, and the tint information regarding the tint of the rice to be cooked is measured over time, and based on the measured tint information. The rice content of the rice to be cooked is judged to be saturated and the water content of the rice to be cooked is suitable for rice cooking. Therefore, it is possible to easily and accurately determine that the rice to be cooked is suitable for rice cooking. This can contribute to improving the taste of cooked cooked rice.

In addition, the inventors conducted an experiment that the intensity of light at each wavelength obtained by spectrally dividing the light from the rice to be cooked has a correlation with the water content, and can be used to evaluate the water content of the rice to be cooked. Clearly revealed. That is, according to the above characteristic configuration, the light from the rice to be cooked is dispersed, and the intensity of the light for each wavelength obtained is used as the tint information, so that the water content of the rice to be cooked is evaluated more reliably, It can be more simply and accurately determined that the rice to be cooked is in a state suitable for cooking rice.

In the case of "immersing in water", the water is not limited to room temperature water, but includes cooled and heated water, and the temperature of immersion in water does not matter. In addition to dipping only rice in water, dipping ingredients other than rice, such as cooked rice, and other ingredients such as seasonings and fruit juice dissolved in water The case is also included in the state of “immersing in water”.

Here, various methods can be used to determine whether or not the water content of the rice to be cooked is saturated and the rice to be cooked has a water content suitable for rice cooking. For example, a method of determining the saturated state when the tint information exceeds a predetermined threshold value, a method of determining the saturated state when the rate of change of the tint information becomes smaller than the predetermined threshold value, and the like can be considered. As the threshold value used in such a case, a value which is set in consideration of a measurement error, an influence degree at the time of cooking rice, etc. and which takes a predetermined allowable range into consideration can be appropriately adopted.

Another characteristic feature of the method for determining the water content state of rice to be cooked according to the present invention for achieving the above-mentioned purpose is to optically observe the rice to be cooked soaked in water and to color the color of the rice to be cooked. A measuring step of measuring taste information over time,
Based on the measured color information, the determination step of determining whether the moisture content of the rice to be cooked is saturated and the rice to be cooked is in a moisture state suitable for rice cooking,
In the measuring step, the light from the rice to be cooked is detected and the obtained signal is L ^* a ^* b ^* L obtained by converting to the value of the color system ^* Ingredient, a ^* Ingredient, b ^* At least one of the components is used as the tint information.
Another characteristic feature of the water content determination device according to the present invention for achieving the above object is to store rice to be cooked rice, and a measuring container to be immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the color information measured by the measuring unit, the rice content of the rice to be cooked is saturated, and the rice to be cooked has a determination unit that determines whether or not the rice has a water content suitable for rice cooking,
In the measuring unit, the light from the rice to be cooked is detected, and the obtained signal is L ^* a ^* b ^* L obtained by converting to the value of the color system ^* Ingredient, a ^* Ingredient, b ^* At least one of the components is used as the tint information.

According to the above characteristic configuration, the rice to be cooked in rice that has been immersed in water is optically observed, and the tint information regarding the tint of the rice to be cooked is measured over time, and based on the measured tint information. , It is determined whether or not the moisture content of the rice to be cooked is saturated and the rice to be cooked is in a water-containing state suitable for rice cooking, so it can be easily and accurately determined that the rice to be cooked rice is in a state suitable for rice cooking. , It can contribute to improve the taste of cooked rice.
Also, L ^* a ^* b ^* The color system (CIELAB) is one of the color spaces having a substantially uniform rate perceptually, and is the most commonly used color system for expressing a color difference (a difference between colors). The inventors used the signal detected by optical observation as L ^* a ^* b ^* L obtained by converting to the color system ^* Ingredient, a ^* Ingredient, b ^* It was clarified experimentally that all of the ingredients were related to the water content and could be used to evaluate the water content of the rice to be cooked. That is, according to the above characteristic configuration, the light from the rice to be cooked is detected, and the obtained signal is L ^* a ^* b ^* L obtained by converting to the value of the color system ^* Ingredient, a ^* Ingredient, b ^* Since at least one of the ingredients is used as color information, it is possible to more reliably evaluate the water content of the rice to be cooked, and to more easily and accurately determine that the rice to be cooked is in a state suitable for rice cooking. ..
In the case of "immersing in water", the water is not limited to room temperature water, but includes cooled and heated water, and the temperature of immersion in water does not matter. In addition to dipping only rice in water, dipping ingredients other than rice, such as cooked rice, and other ingredients such as seasonings and fruit juice dissolved in water The case is also included in the state of “immersing in water”.

Another characteristic configuration of the method for determining the water content state of rice to be cooked according to the present invention is the above b. ^* The component is the tint information.

b ^* Ingredient is L ^* Component and a ^* It was shown in the experiment that the change in the water content of rice to be cooked was larger than that of the ingredients. That is, according to the above characteristic configuration, b ^* By using the components as color information, it is possible to more accurately evaluate the water content of the rice to be cooked.

Another characteristic configuration of the method for determining the water content state of rice to be cooked according to the present invention is that the tint information is obtained from the light transmitted through a plurality of rice to be cooked in the measuring step.

It is not clear why the color of the rice to be cooked changes as it absorbs water, but the physical properties of the starchy material of the rice to be cooked change as the water content increases, and the state of light absorption and scattering changes. Presumed to be present. For example, it is presumed that the crystal structure of starch is changed by the penetration of water molecules, and the optical characteristics are changed. According to the above characteristic configuration, in the measuring step, by obtaining the tint information from the light that has passed through the plurality of rice to be cooked, the change in light due to the transmission of the rice to be cooked is greater, and the tint This is preferable because it is largely reflected by changes in information.

Another characteristic feature of the method for determining the water content state of the rice to be cooked according to the present invention for achieving the above-mentioned purpose is to irradiate visible light to the rice to be cooked in water and optically observe the rice to cook rice. A measurement step of measuring color information regarding color of rice over time,
Based on the measured color information, the determination step of determining whether the moisture content of the rice to be cooked is saturated and the rice to be cooked is in a moisture state suitable for rice cooking,
In the measuring step, the color information is obtained from the light transmitted through the plurality of rices to be cooked.
Further, the characteristic configuration of another water content state determination device according to the present invention to achieve the above object, the rice to be cooked rice is contained, a measurement container to be immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the color information measured by the measuring unit, the rice content of the rice to be cooked is saturated, and the rice to be cooked has a determination unit that determines whether or not the rice has a water content suitable for rice cooking,
In the measuring unit, the tint information is obtained from the light transmitted through the plurality of rices to be cooked.

According to the above characteristic configuration, the rice to be cooked for cooking which is soaked in water is optically observed, and the tint information regarding the tint of the rice to be cooked is measured over time, based on the measured tint information, Since it is determined whether or not the water content of the rice to be cooked is saturated and the rice to be cooked is in a water content state suitable for rice cooking, it can be easily and accurately determined that the rice to be cooked rice is in a state suitable for rice cooking. It can contribute to improving the taste of cooked rice.
It is not clear why the color of the rice to be cooked changes with water absorption, but the physical properties of the starch quality of the rice to be cooked change as the water content increases, and the absorption and scattering of light also changes. It is speculated that For example, it is presumed that the crystal structure of starch is changed by the penetration of water molecules, and the optical characteristics are changed. According to the above characteristic configuration, in the measuring step, by obtaining the tint information from the light that has passed through the plurality of rice to be cooked, the change in light due to the transmission of the rice to be cooked is greater, and the tint This is preferable because it is largely reflected by changes in information.

Another characteristic configuration of the method for determining a water content state of rice to be cooked according to the present invention is that, in the measuring step, a plurality of rice to be cooked is housed in a measurement container in a state of being stacked in the vertical direction, and in a direction intersecting with the vertical direction. The point is to optically observe the rice to be cooked from a certain horizontal direction.

According to the above characteristic configuration, the rice to be cooked is housed in the measurement container in a state of being stacked in the vertical direction, and the rice to be cooked is optically observed from the lateral direction which is the direction intersecting the vertical direction. This is preferable because the movement and posture change of the target rice during the measurement are suppressed, the disturbance to the optical observation is reduced, and the accuracy of the measurement of the tint information is improved.

The characteristic configuration of the immersion time determining device of the present invention for achieving the above object is to store rice to be cooked rice, and a measuring container to be immersed in water ,
A measuring unit that irradiates visible light to the rice to be cooked contained in the measurement container and optically observes it, and measures the tint information regarding the tint of the rice to be cooked over time .
Based on the color information the measuring portion is measured, the cooking object rice with moisture content of rice target rice saturated, have a determining section for determining the immersion time required to reach the water state suitable for cooking ,
In the measuring unit, the light from the rice to be cooked is dispersed, and the intensity of light obtained for each wavelength is used as the tint information .
Further, the characteristic configuration of another immersion time determining device according to the present invention for achieving the above object is to store rice to be cooked rice, a measuring container to be immersed in water,
A measuring unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked with time.
Based on the tint information measured by the measuring unit, a deciding unit for deciding a dipping time required for the water content of the rice to be cooked is saturated and the rice to be cooked reaches a water content suitable for rice cooking. ,
In the measuring unit, the light from the rice to be cooked is detected, the obtained signal is converted into the value of the L ^* a ^* b ^* color system, and the obtained L ^* component, a ^* component and b ^* component are obtained. At least one of them is used as the tint information.
Furthermore, another characteristic feature of the immersion time determining device according to the present invention for achieving the above object is that the rice to be cooked is accommodated, and the measuring container is immersed in water.
A measuring unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked with time.
Based on the tint information measured by the measuring unit, a deciding unit for deciding a dipping time required for the water content of the rice to be cooked is saturated and the rice to be cooked reaches a water content suitable for rice cooking. ,
In the measuring unit, the tint information is obtained from light transmitted through a plurality of rices to be cooked.

While examining the evaluation method of the water content state of the rice to be cooked, the inventors have noticed that the color changes as the rice to be cooked absorbs water. The rice to be cooked in the experiment had a slightly yellow color before absorbing water, but when it absorbed water, it changed to a transparent white color. Then, the inventors experimentally confirmed that there is a strong correlation between the color information obtained by optically observing the rice to be cooked and the water content of the rice to be cooked, and thus the present invention was completed. It has arrived.

That is, according to the above-mentioned characteristic configuration, a measurement container that stores rice to be cooked and is immersed in water,
Optically observing the rice to be cooked contained in the measurement container, based on the tint information measured by the measuring unit and the measuring unit that measures the tint information regarding the tint of the rice to be cooked over time, Since the water content of the rice to be cooked is saturated and the soaking time required for the rice to be cooked reaches the water content suitable for rice cooking, the rice has a determining unit that determines the water content suitable for rice cooking. The required soaking time can be determined easily and accurately, which can contribute to improving the taste of cooked cooked rice.

In the case of "immersing in water", the water is not limited to room temperature water, but includes cooled and heated water, and the temperature of immersion in water does not matter. In addition to dipping only rice in water, dipping ingredients other than rice, such as cooked rice, and other ingredients such as seasonings and fruit juice dissolved in water The case is also included in the state of “immersing in water”.

Here, various methods can be used to determine the soaking time required for the rice content of the rice to be cooked to reach a water content state suitable for the rice to be saturated. For example, when the rice to be cooked is dipped in water as a starting point, the time from that point to the time when the rice to be cooked is determined to be in a water-containing state suitable for cooking by the above-mentioned determination step is defined as the soaking time. You can decide. In addition, a method of determining the immersion time by estimating that the water content is saturated at a time point (for example, 10 minutes ahead) after a predetermined time from the time when the color information exceeds a predetermined threshold as a starting point, and the color information When the rate of change with respect to time becomes smaller than a predetermined threshold value as a starting point, the water content is estimated to be saturated at a predetermined time point (for example, 10 minutes ahead), and a method for determining the immersion time A method is conceivable in which a time change graph of information is compared with a plurality of experimental data stored in a database and the immersion time is estimated and determined from experimental data having a high degree of similarity.

The characteristic configuration of the rice cooking equipment of the present invention to achieve the above object is the above-mentioned immersion time determining device, and an immersion device for immersing rice to be cooked in water based on the immersion time determined by the immersion time determining device. And a rice cooker for cooking the rice to be cooked which has absorbed water in the dipping device.

According to the above characteristic configuration, since the dipping device dips the rice to be cooked in water based on the dipping time determined by the dipping time determining device, the water content of the rice to be cooked is suitable for cooking rice. .. Since the rice cooker cooks the rice to be cooked, the cooked rice to be cooked has excellent taste. That is, according to the above-mentioned rice cooker, the rice to be cooked is made to have a water content suitable for rice cooking, and then rice is cooked, so that cooked rice having an excellent taste can be provided.

Schematic diagram showing the configuration of the water content determination device Graph showing changes in L ^* component as tint information Graph showing changes in a ^* component as tint information Graph showing changes in b ^* component as tint information Graph showing changes in water content of rice for cooking rice Graph showing the correlation between the moisture content of rice to be cooked and the L ^* component Graph showing the correlation between the moisture content of rice to be cooked and the a ^* component Graph showing the correlation between the moisture content of boiled rice and b ^* component Graph showing the change with the intensity change rate of light for each wavelength obtained by spectrally dividing the light from the rice to be cooked A graph showing the correlation between the water content of rice to be cooked and the light intensity for each wavelength. Schematic diagram showing the structure of rice cooking equipment

(First embodiment)
Hereinafter, the water content state determination device and the water content state determination method for rice to be cooked according to the first embodiment will be described.

(Water content determination device)
The water content state determination device 4 illustrated in FIG. 1 includes a measurement container 41, a measurement unit D, and a determination unit. The measurement container 41 stores the rice to be cooked and is immersed in water. The measurement unit D optically observes the rice R to be cooked contained in the measurement container 41 and measures the tint information regarding the tint of the rice R to be cooked over time with time. The determination unit determines, based on the tint information measured by the measurement unit D, whether the water content of the rice R to be cooked is saturated and the rice R to be cooked is in a water content state suitable for rice cooking.

The measurement container 41 is a cylindrical container having a bottom surface B, and is arranged with the bottom surface B facing downward with the central axis along the vertical direction. The upper side in the vertical direction of the measurement container 41 is open. The measurement container 41 may have a cylindrical shape or a rectangular tube shape, but in the present embodiment, the cylindrical shape will be described. Further, it is desirable that the measurement container 41 be formed of a transparent material so that the tint information can be easily measured. If the tint information can be measured, it can be formed of a translucent or colored material.

A plurality of rice R to be cooked is put into the measurement container 41 from the upper opening, and the rice R is stacked vertically. Then, water is poured from the opening, so that the rice R to be cooked is immersed in water. As described above, "water" is not limited to water at room temperature, but includes cooled and heated water, and also contains seasonings and food additives. It is preferable to use the temperature and the component "water" used when actually cooking the rice R to be cooked.

The measurement unit D is configured to obtain the tint information from the light transmitted through the plurality of rice R to be cooked. Further, the measurement unit D is configured to optically observe the plurality of cooked rice R contained in the measurement container 41 in a vertically stacked state from a lateral direction which is a direction intersecting the vertical direction. In the present embodiment, as shown in FIG. 1, a light projecting portion 43 is arranged on the lateral side of the measurement container 41 so as to extend in the vertical direction. A light detection unit 44 is arranged at a position facing the light projecting unit 43 with the measurement container 41 interposed therebetween, extending in the vertical direction. The light projecting section 43 is a white light source such as an LED. The light detection unit 44 is a sensor that can detect the tint of the observation target from the received light, and for example, a digital camera that captures a color image can be used.

In this embodiment, white light is emitted from the light projecting unit 43 toward the light detecting unit 44. The light from the light projecting unit 43 travels in the horizontal direction (the lateral direction that intersects the vertical direction). Here, as shown in FIG. 1, in the present embodiment, the horizontal width of the measuring container 41 is set to a size in which two rice R to be cooked horizontally or four rice R to be cooked vertically are arranged. Therefore, the light from the light projecting unit 43 passes through the two or four rices R to be cooked in rice arranged in the lateral direction and reaches the light detecting unit 44. The digital camera as the light detection unit 44 detects the light that has passed through the rice R to be cooked and records it as an image signal. Then, the signal processing device (not shown) of the measurement unit D converts the signal corresponding to the light from the rice R to be cooked rice into the L ^* a ^* b ^* colorimetric system value in the obtained image signal by a known method. The conversion is performed to obtain the L ^* component, the a ^* component, and the b ^* component.

2 to 4 are examples of changes over time in the L ^* component, the a ^* component, and the b ^* component measured and converted by the measuring unit D. In the experiment, Koshihikari from Tamba, which was harvested in 2014, was used as the rice R to be cooked. The experiment was performed in an environment of room temperature of 25°C. The rice R to be cooked was stored in the measurement container 41 without being washed. Then, water (tap water) was poured into the measurement container 41, and the rice R to be cooked was immersed in water. The rice R to be cooked was photographed with the light detection unit 44 over time, and the L ^* component, a ^* component, and b ^* component were calculated from the obtained image signal. In the graphs of FIGS. 2 to 4, the rate of change is expressed as a percentage, with the size of each component at the time of starting the immersion in water (time 0) as a reference value.

From the graph of FIG. 2, it is recognized that the L ^* component rapidly decreases after the start of the immersion in water, and thereafter, the decreasing speed becomes slower and gradually approaches a constant value. From the graph of FIG. 3, it is recognized that the a ^* component rapidly increases after the start of immersion in water, and exhibits a behavior in which the rate of increase decreases in the section after 30 minutes. From the graph of FIG. 4, the b ^* component, like the L ^* component, rapidly decreases after the start of immersion in water, and thereafter, the rate of decrease gradually slows down and gradually approaches a constant value. Is recognized.

Next, the rice R to be cooked in the same production lot as that used in the experiment was immersed in water (tap water), and the water content was measured using a moisture content meter. FIG. 5 is a graph showing changes in water content with time. From the graph of FIG. 5, it is recognized that the water content shows a behavior in which the water content rapidly increases after the start of immersion in water, and thereafter the rate of increase becomes gentle.

6 to 8 are plots of data at each measurement time, where the horizontal axis represents the water content and the vertical axis represents the rate of change of the L ^* component, the a ^* component, and the b ^* component. From the graph of FIG. 6, it is recognized that there is a strong negative correlation between the water content and the L ^* component. From the graph of FIG. 7, it is recognized that there is a positive correlation between the water content and the a ^* component. From the graph of FIG. 8, it is recognized that there is a strong negative correlation between the water content and the b ^* component. Utilizing this correlation, the water content of the cooked rice is saturated based on the measured L ^* component, a ^* component, and b ^* component values (color information), and the cooked rice is suitable for cooking rice. It is possible to determine whether or not the water content has changed. That is, it is possible to evaluate the degree of expansion of the rice R to be cooked, which is the secondary information, based on the tertiary information called the tint information, and to estimate the water content of the rice R to be cooked, which is the primary information. Confirmed experimentally.

That is, the determination unit (not shown) of the water content state determination device 4 is a water content state in which the rice content R of rice to be cooked is saturated and the rice R to be cooked is suitable for rice cooking based on the tint information measured by the measurement unit D. Is determined. Various methods can be used for the determination. For example, a method of determining the saturated state when the tint information exceeds a predetermined threshold value, a method of determining the saturated state when the change rate of the tint information becomes smaller than the predetermined threshold value, and the like can be considered. In the example of the graphs of FIGS. 2 to 4, it is considered that the water content of the rice R to be cooked is saturated during 30 to 60 minutes.

(Method of determining water content)
In the moisture content determination device 4 described above, the following moisture content determination method for rice to be cooked is performed. The method for determining the water content of rice to be cooked includes a measuring step and a determining step.

In the measuring step, the rice R to be cooked, which is immersed in water, is optically observed, and the tint information regarding the tint of the rice to be cooked is measured with time. The tint information is obtained from the light transmitted through the plurality of rices to be cooked. In the measurement, a plurality of rice R to be cooked is placed in the measurement container 41 in a state of being stacked in the vertical direction, and the measuring unit D optically observes the rice to be cooked from the lateral direction that intersects the vertical direction. .. Then, the obtained signal is converted into a value of the L ^* a ^* b ^* color system, and at least one of the obtained L ^* component, a ^* component, and b ^* component is used as tint information.

In the determining step, it is determined based on the measured tint information whether or not the water content of the rice R to be cooked is saturated and the rice to be cooked is in a water-containing state suitable for rice cooking.

(Second embodiment)
In the following description of the second and subsequent embodiments, the same members as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. In the first embodiment described above, the light from the rice to be cooked is detected, the obtained signal is converted into the value of the L ^* a ^* b ^* color system, and the obtained L ^* component, a ^* component, At least one of the b ^* components was used as tint information. In the second embodiment, this is modified to disperse the light from the rice R to be cooked, and the obtained light intensity for each wavelength is used as the tint information.

In the water content state determination device according to the second embodiment, as the light detection unit 44, a spectrophotometer capable of dispersing the light from the rice R to be cooked and measuring the intensity of the light for each wavelength is used. That is, the measurement unit D disperses the light from the rice R to be cooked and records the intensity of the light for each wavelength to obtain the tint information.

FIG. 9 is an example of a temporal change of the light intensity for each wavelength measured by the measuring unit D. In the experiment, as rice R to be cooked rice, Koshihikari from Tamba produced in 2014, which was the same as the experiment in the first embodiment, was used. The experiment was performed in an environment of room temperature of 25°C. The rice R to be cooked was stored in the measurement container 41 without being washed. Then, water (tap water) was poured into the measurement container 41, and the rice R to be cooked was immersed in water. Then, the light from the rice R to be cooked was dispersed by the light detection unit 44, and the intensity of the light for each wavelength was measured with time. In the graph of FIG. 9, light having wavelengths of 420 nm, 550 nm, and 680 nm is measured, and the rate of change is expressed as a percentage with the intensity of each wavelength when immersion in water is started (time 0) as a reference value.

From the graph of FIG. 9, the intensity of any light of 420 nm, 550 nm, and 680 nm decreases rapidly after the start of immersion in water, and then the decrease speed becomes slower, and the behavior gradually approaches a constant value. It is accepted to show. The intensity of light having a wavelength of 550 nm and the intensity of light having a wavelength of 680 nm among the lights having the three wavelengths showed a decrease of 5% or more in 10 minutes from the start of immersion. If the intensity changes to this extent, it is possible to perform appropriate measurement with little error.

In FIG. 10, the horizontal axis represents the water content (the value measured in the experiment of the first embodiment), and the vertical axis represents the intensity (rate of change) of light having wavelengths of 420 nm, 550 nm, and 680 nm. Is. From the graph of FIG. 10, it is recognized that there is a negative correlation between the water content and the intensity of light of each wavelength. Using this correlation, the moisture content of the rice to be cooked is saturated based on the measured light intensity (color information) of wavelengths 420 nm, 550 nm, and 680 nm, and the moisture content of the rice to be cooked is suitable for cooking rice. It is possible to determine whether or not That is, it is possible to evaluate the degree of expansion of the rice R to be cooked, which is the secondary information, based on the tertiary information called the tint information, and to estimate the water content of the rice R to be cooked, which is the primary information. Confirmed experimentally.

(Third Embodiment)
In the above-mentioned embodiment, the water content state determination device 4 has a determination unit, and based on the tint information measured by the measurement unit D, the moisture content of the rice R to be cooked is saturated and the rice R to be cooked is suitable for rice cooking. It was determined whether or not the water content was reached. The immersion time determination device according to the third embodiment includes a measurement container 41 similar to the water content determination device 4 and a measurement unit D, and includes a determination unit instead of the determination unit. The determining unit determines, based on the tint information measured by the measuring unit D, the immersion time required for the water content of the rice R to be cooked to be saturated and the rice R to be cooked to reach a water-containing state suitable for rice cooking.

As described above, the tint information measured by the measuring unit D reflects the degree of expansion of the rice R to be cooked and has a correlation with the water absorption rate of the rice R to be cooked. Therefore, based on the tint information measured by the measuring unit D, the immersion time required for the water content of the rice R to be cooked to reach saturation and the rice R to be cooked to reach a water-containing state suitable for rice cooking can be determined. .. Here, various methods can be used to determine the immersion time. For example, when the rice R to be cooked rice is immersed in water as a starting point, the time from that point to the time when the rice R to be cooked rice is determined to be in a water-containing state suitable for rice cooking by the above-mentioned determination step It can be decided as time. In addition, a method may be considered in which the water content is estimated to be saturated at a time point (for example, 10 minutes ahead) a predetermined time after the time point when the tint information exceeds a predetermined threshold as a starting point, and the immersion time is determined. In addition, it is estimated that the water content is saturated at a time point (for example, 10 minutes ahead) a predetermined time after the time point when the rate of change of the tint information with time becomes smaller than a predetermined threshold value, and the immersion time is determined. There are possible ways to do it. Further, a method of comparing the time change graph of the tint information with a plurality of experimental data accumulated in the database and estimating the immersion time from the experimental data having a high degree of similarity can be considered.

(Fourth Embodiment)
The rice cooking equipment according to the fourth embodiment is the above-mentioned immersion time determining device 4, the immersion device 2 for immersing the rice R for rice cooking in water based on the immersion time determined by the immersion time determining device 4, and the immersion device. 2 has a rice cooker 3 which cooks the rice R to be cooked which has absorbed water.

Specifically, as shown in FIG. 11, the rice cooking equipment includes a rice washing machine 1, a dipping device 2, a rice cooking device 3, a dipping time determination device 4, a transfer device 5, and a control device 6.

(Control device)
The control device 6 is composed of a microcomputer having a CPU, a memory, etc., and controls the operation of each dipping device 2, the dipping time determining device 4, the transfer device 5, and the rice cooking device 3 to determine the dipping device 2 and the dipping time. It functions as a part of the device 4, the transfer device 5, and the rice cooking device 3.

(Immersion device)
The dipping device 2 is equipped with a dipping container 21 for weighing and receiving washed rice R supplied from the rice washing machine 1 and receiving water corresponding to the weight of rice to dip and hold the rice R in water. 21 is provided with an outlet 22 for taking out the rice R that has been soaked, and an opening/closing control valve 23 is provided at the outlet 22, so that the immersion is completed based on an opening/closing instruction from the control device 6 and the rice is immersed in water. The rice R is configured to be freely discharged from the immersion container 21.

With such a configuration, the rice R supplied to the immersion container 21 is immersed in water after being weighed, and the immersion is completed by the opening operation of the opening/closing control valve 23 from the control device 6.

(Transfer device)
The transfer device 5 includes a drainer 51 for draining the soaked rice R discharged from the outlet 22 of the soaker 2, and a transfer part 52 for transferring the drained soaked rice R to the rice cooker 3. Equipped with.

With such a configuration, the rice R that has been dipped can be drained and then put into the rice cooker 30 provided in the weighing unit 31 provided in the rice cooker 3 described later.

(Rice cooker)
The rice-cooking device 3 measures the rice R put in the rice-cook 30 and adds water according to the amount of the rice R to prepare rice, and the heating device 32a puts the rice-cook 30 in the rice-cook 30. A heating unit 32 that heats and cooks the rice R, and a take-out unit 33 that loosens the cooked rice R and allows the rice R to be taken out are provided. The rice cooker 30 prepared for rice cooking by the weighing unit 31 is sequentially transported to the heating unit 32 and the take-out unit 33 by the transport device 34 whose operation is controlled by the controller 6.

With such a configuration, the rice R received from the transfer device 5 is sequentially heated by the control device 6 with appropriate heating and heating to be processed into cooked rice, for example, a downstream side which is individually packaged in a container such as a bento box. It can be delivered to devices.

Here, the dipping device 2 dips the rice R to be cooked in water in water based on the dipping time determined by the dipping time determining device 4. Specifically, the immersion time determined by the immersion time determination device 4 is notified to the control device 6, and the control device 6 controls the immersion device 2 to immerse the rice R to be cooked in water in water.

The immersion time determining device 4 may be built in the rice cooking equipment or may be installed side by side with the rice cooking equipment. The immersion time determining device 4 and the rice cooking facility may be provided in a remote location, and the immersion time data may be transmitted from the immersion time determining device 4 to the control device 6 of the rice cooking facility.

The time-dependent measurement of the tint information of the rice R targeted for rice cooking and the determination of the immersion time in the immersion time determination device 4 are started and completed (1) prior to the immersion of the rice R targeted for rice cooking in water in the rice cooking equipment. Alternatively, (2) the processes may be started and performed in parallel about 15 minutes earlier, or (3) the processes may be started simultaneously and performed in parallel.

In the case of (1), for example, the soaking time is determined in advance for each type and lot (rice, production time, rice polishing process, etc.) of the rice R to be cooked, and the determined soaking time is the control device 6 of the rice cooking equipment. May be selected for each type or lot of rice R to be cooked. For example, on the day when the rice cooking device is operated, the immersion time determination device 4 may determine the immersion time for the rice R to be cooked rice used on that day at the start of the morning.

In the case of (2), for example, when a certain lot of rice R to be cooked is cooked, a part of the rice R to be cooked is housed in the measuring container 41 of the immersion time determination device 4 and immersed in water to obtain tint information Is measured over time to determine the immersion time. In the rice cooker, the immersion in the immersion device 2 is started with a delay of 15 minutes from the start of the immersion in the immersion time determination device 4. Then, when the immersion time determination device 4 determines the immersion time, the control device 6 receives the data, controls the immersion device 2 based on the immersion time, and completes the immersion.

In the case of (3), a part of rice R to be cooked which is cooked in the rice cooking facility is extracted and stored in the measuring container 41 of the immersion time determining device 4. Then, the immersion in the immersion time determining device 4 and the immersion in the immersion device 2 of the rice cooking equipment are simultaneously started. When the immersion time is determined by the immersion time determination device 4, the immersion time is transmitted to the control device 6. The control device 6 controls the dipping device 2 based on the received dipping time to complete the dipping of the rice R to be cooked.

The dipping in the dipping device 2 based on the dipping time may be performed for the same time as the dipping time, or for an increased or decreased time in consideration of, for example, temperature and humidity.

(Other embodiment)
(1) In the above-described embodiment, the rice cooking equipment has the immersion time determining device, and the immersion in the immersion device 2 of the rice cooking equipment is controlled based on the immersion time determined by the immersion time determining device. This may be modified so that the rice cooking equipment has a water content state determination device instead of the immersion time determination device. In this case, the dipping device 2 of the rice cooking equipment is based on the water content determination device determining whether or not the water content of the rice to be cooked is saturated and the rice to be cooked is in a water content suitable for rice cooking. Control the immersion of the rice R, which is the target rice for cooking in 2, in water. For example, when the water content determination device determines that the water content of the rice to be cooked is saturated and the rice to be cooked is in a water content suitable for rice cooking, the rice to be cooked R in the dipping device 2 is immersed in water. To complete.

(2) In the above-described first embodiment, a digital camera is used as the light detection unit 44, and the light detection unit 44 detects light that has passed through the rice R to be cooked and records it as an image signal. The light detection unit 44 is not limited to a digital camera, but may be a color sensor, for example. The color sensor records the intensity of the received light by dividing it into the intensities of light of three colors of red (R), green (G), and blue (G).

(3) In the above-described embodiment, as shown in FIG. 1, the light projecting portion 43 is arranged on the lateral side of the measurement container 41 so as to extend in the vertical direction. A light detection unit 44 is arranged at a position facing the light projecting unit 43 with the measurement container 41 interposed therebetween, extending in the vertical direction. That is, the light from the light projecting unit 43 travels in the horizontal direction, passes through the rice R to be cooked, and reaches the light detecting unit 44. The direction of the light, that is, the observation direction of the rice R to be cooked by the measuring unit is not limited to this, and may be a direction diagonally intersecting the vertical direction or a direction parallel to the vertical direction. It is also possible to arrange the light projecting unit 43 and the light receiving unit 44 on the same side with respect to the measurement container 41 so that the light receiving unit 44 observes the reflected light from the rice R to be cooked.

(4) In the above-described embodiment, a plurality of rices to be cooked are stacked in the vertical direction, housed in a measurement container, and measured. It is also possible to measure one piece of rice that is the target of rice cooking for the measurement of color information.

Note that the configurations disclosed in the above-described embodiments (including the other embodiments, the same applies hereinafter) can be applied in combination with the configurations disclosed in the other embodiments, as long as no contradiction occurs. The embodiment disclosed in the present specification is an example, and the embodiment of the present invention is not limited to this, and can be appropriately modified within a range not departing from the object of the present invention.

2: Immersion device 3: Rice cooker 4: Water content determination device, immersion time determination device 41: Measuring container D: Measuring part R: Rice to be cooked

Claims (13)

A measurement step of irradiating visible light to the rice to be cooked soaked in water for optical observation, and measuring the tint information regarding the tint of the rice to be cooked over time.
And based on the measured color information, have rows and determining step cooking target rice moisture content of rice target rice is saturated is whether a water-containing state suitable for cooking,
In the measuring step, the water content determination method of rice to be cooked is characterized in that the light from the rice to be cooked is dispersed, and the intensity of light obtained for each wavelength is used as the tint information . A measurement step of optically observing the rice to be cooked soaked in water and measuring the tint information regarding the tint of the rice to be cooked over time.
Based on the measured color information, the determination step of determining whether the moisture content of the rice to be cooked is saturated and the rice to be cooked is in a moisture state suitable for rice cooking,
In the measuring step, the light from the rice to be cooked is detected, the obtained signal is converted into the value of the L ^* a ^* b ^* color system, and the obtained L ^* component, a ^* component and b ^* component are obtained. A method for determining a water content state of rice to be cooked, wherein at least one of them is used as the color information. The water content determination method for rice to be cooked according to claim 2 , wherein the b ^* component is used as the color information. A measurement step of irradiating visible light to the rice to be cooked soaked in water for optical observation, and measuring the tint information regarding the tint of the rice to be cooked over time.
Based on the measured color information, the determination step of determining whether the moisture content of the rice to be cooked is saturated and the rice to be cooked is in a moisture state suitable for rice cooking,
In the measuring step, a method for determining a water content state of rice to be cooked, wherein the color information is obtained from light transmitted through a plurality of rice to be cooked. Wherein the measurement step, claim 1-3 or cooking object rice moisture state determination method according to one of the from the light transmitted through the plurality of cooking target rice obtain the color information. In the measuring step, housed in the measurement vessel in a state of stacking a plurality of cooking object rice in the vertical direction, the lateral direction of the claims 1-5 to observe the cooking object rice optically a direction crossing the vertical direction The method for determining a water content state of rice to be cooked according to any one of items. A measuring container that contains the rice to be cooked and is immersed in water,
A measurement unit that irradiates visible light to the rice to be cooked contained in the measurement container and optically observes it, and measures the tint information regarding the tint of the rice to be cooked over time.
The measurement unit based on the color information measured, rice target rice have a determining unit whether it is a water-containing state suitable for cooking and water content of the rice target rice is saturated,
The water content state determination device, wherein the measuring unit disperses light from rice to be cooked and uses the obtained light intensity for each wavelength as the tint information . A measuring container that contains the rice to be cooked and is immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the color information measured by the measuring unit, the rice content of the rice to be cooked is saturated, and the rice to be cooked has a determination unit that determines whether or not the rice has a water content suitable for rice cooking,
In the measuring unit, the light from the rice to be cooked is detected, and the obtained signal is L ^* a ^* b ^* L obtained by converting to the value of the color system ^* Ingredient, a ^* Ingredient, b ^* A water content state determination device in which at least one of the components is used as the tint information. A measuring container that contains the rice to be cooked and is immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the color information measured by the measuring unit, the rice content of the rice to be cooked is saturated, and the rice to be cooked has a determination unit that determines whether or not the rice has a water content suitable for rice cooking,
A water content determination device for obtaining the color information from the light transmitted through a plurality of rices to be cooked in the measuring unit. A measuring container that contains the rice to be cooked and is immersed in water,
A measuring unit that irradiates visible light to the rice to be cooked contained in the measurement container and optically observes it, and measures color information regarding the color of the rice to be cooked over time.
Based on the color information the measuring portion is measured, the cooking object rice with moisture content of rice target rice saturated, have a determining section for determining the immersion time required to reach the water state suitable for cooking ,
A dipping time determination device in which light from the rice to be cooked is dispersed in the measuring unit, and the intensity of light obtained for each wavelength is used as the tint information . A measuring container that contains the rice to be cooked and is immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the tint information measured by the measuring unit, a deciding unit for deciding a dipping time required for the water content of the rice to be cooked to reach a water-containing state suitable for the rice to be cooked due to saturation ,
In the measuring unit, the light from the rice to be cooked is detected, and the obtained signal is L ^* a ^* b ^* L obtained by converting to the value of the color system ^* Ingredient, a ^* Ingredient, b ^* An immersion time determining device in which at least one of the components is the tint information. A measuring container that contains the rice to be cooked and is immersed in water,
A measurement unit that optically observes the rice to be cooked contained in the measurement container, and measures the tint information regarding the tint of the rice to be cooked over time.
Based on the tint information measured by the measuring unit, a deciding unit for deciding a dipping time required for the water content of the rice to be cooked to reach a water-containing state suitable for the rice to be cooked due to saturation ,
An immersion time determining device that obtains the color information from the light transmitted through a plurality of rices to be cooked in the measuring unit. In the dipping time determination device according to any one of claims 10 to 12, a dipping device that dips the rice to be cooked in water in water based on the dipping time determined by the dipping time determination device, and the dipping device. Rice-cooking equipment that has a rice-cooking device that cooks rice that has absorbed water.

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