JP7386744B2 - Digestibility determination system and digestibility determination method - Google Patents

Description

The present invention relates to a system and method for determining the digestibility of sake rice heated in the presence of water.

In food processing fields that use rice as raw material, such as cooked rice processing and sake brewing, aging of rice is an important factor that determines the quality of the product. For example, in the process of manufacturing cooked rice processed foods such as bento boxes and rice balls, cooked rice (cooked rice) is molded after cooling, but cooked rice ages during the cooling process, causing deterioration in texture (e.g. hardening, agglomeration). This causes problems such as deterioration of processability during molding and deterioration of the taste of processed foods.In addition, it is difficult to understand the degree of aging of cooked rice. It is important in controlling the quality of processed foods during storage and distribution processes. On the other hand, in the sake brewing process, the degree of aging of the steamed rice (steamed rice) that serves as the raw material affects the decomposition by microorganisms during the fermentation process, so understanding the degree of aging of the steamed rice is important for quality control of sake. It is important to do so.

Conventionally, techniques described in Patent Documents 1 to 4, for example, have been proposed as techniques for determining the degree of aging of cooked rice or steamed rice.

Specifically, the technology described in Patent Document 1 focuses on the fact that there is a correlation between the aging properties of rice and the urea disintegration properties and alkali disintegration properties of rice, and soaks the rice to be evaluated in an aqueous urea solution or an aqueous alkaline solution. The disintegration properties of the rice to be evaluated in these aqueous solutions are evaluated, and the aging properties of rice are evaluated using these urea disintegration properties and alkali disintegration properties as indicators.

In addition, in the technology described in Patent Document 2, rice is immersed in a gelatinizing solution such as an alkaline solution or a urea solution, and the amount of eluted starch in the solution is detected by an iodine starch color reaction, and the amount of eluted starch is The senility of rice is evaluated based on the correlation with the senility of rice.

On the other hand, Patent Document 3 discloses that X-rays are irradiated onto foods prepared by cooking starch-containing grains such as rice and wheat in the presence of water, and based on the intensity of diffracted X-rays at a prescribed diffraction angle, A technique for determining the degree of aging of starch-containing foods is disclosed.

In addition, the technology described in Patent Document 4 measures the gelatinization characteristic values (gelatinization start temperature, viscosity, etc.) of a grain sample, performs an analysis using the measured gelatinization characteristic values, and uses the analysis results to determine the gelatinization characteristic value of the grain sample. This is what gives it aging properties.

JP 2016-57278 Publication Japanese Patent Application Publication No. 2017-161399 JP2016-70860A Japanese Patent Application Publication No. 2005-221344

By the way, in the field of sake brewing, after aging steamed sake rice, this aged sake rice is used to make moromi. The goal is to control the degree of decomposition (i.e., digestibility) of sake rice.

The digestibility of steamed sake rice depends on the crystallinity of the sake rice after aging, so aging the same sake rice for the same amount of time does not necessarily mean that the digestibility will be the same. However, the digestibility of steamed sake rice after aging differs depending on the surrounding environment during aging.

Therefore, in the field of sake brewing, there is a need for a method that can predict and evaluate the digestibility of steamed sake rice.

The present invention was made in view of the above circumstances, and an object thereof is to provide a digestibility determination system and a digestibility determination method that can determine the digestibility of sake rice heated in the presence of water.

The characteristic structure of the digestibility determination system according to the present invention for achieving the above object is a system for determining the digestibility of sake rice heated in the presence of water,
an optical means for irradiating the sake rice with polarized light;
Photographing means for photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
image data acquisition means for acquiring polarized image data photographed by the photographing means;
histogram creation means for creating a histogram regarding brightness based on the polarization image data;
a rate of change calculation means that acquires digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculates a change rate of the digestibility determination determination information;
Determining the digestibility of the sake rice using the digestibility determination information obtained from the histogram created by the histogram creation means based on the change rate of the digestibility determination information calculated by the change rate calculation means. Digestibility determination determination means for determining whether or not the digestibility can be determined;
digestibility determination means for determining the digestibility of the sake rice based on the digestibility determination information when the digestibility determination determination means determines that it can be determined ;
The digestibility determination determination information is a histogram-related value selected from among the average value, median value, mode, kurtosis, and skewness obtained from the histogram.

According to the characteristic configuration described above, polarized image data regarding sake rice photographed at at least two or more timings can be acquired, and the acquired polarized image data is processed to create a histogram regarding brightness.
Starches such as amylose and amylopectin contained in sake rice, for example, have a crystal structure in the raw rice state, so polarized images of raw rice have a unique polarized cross that originates from this crystal structure. appears as a high brightness area. On the other hand, in sake rice immediately after steaming, water enters the crystal structure and the crystal structure collapses, so no polarization cross appears in these polarization images. However, in steamed sake rice, water that has entered the crystal structure over time is gradually released to the outside, and the collapsed crystal structure returns one after another (so-called aging), causing these polarized lights to change. A polarized cross appears as a high-brightness area in the image.
As a result of extensive research, the inventor of the present application discovered that digestibility determination information related to the digestibility of sake rice can be obtained from a histogram related to brightness created by processing polarization image data, and this digestibility determination information In addition to obtaining the knowledge that it is possible to determine the digestibility of sake rice based on After calculating the rate of change in the judgment information, based on the calculated rate of change in the digestibility judgment information, we have found that it is possible to judge whether the digestibility judgment information can be used to judge the digestibility of sake rice. As a result, the present invention was completed.
That is, in the characteristic configuration described above, the rate of change calculation means acquires digestibility determination determination information regarding the state of sake rice at two or more timings, and calculates the change rate of the digestibility determination determination information. Then, the digestibility determination determination means determines whether or not the digestibility of the sake rice can be determined using the digestibility determination information, based on the rate of change of the digestibility determination determination information. If the digestibility of the sake rice can be determined, the digestibility of the sake rice can be determined by the digestibility determination means based on the digestibility determination information.
In addition, as a result of extensive research, the inventor of the present application has determined that the average value, median value, mode, kurtosis, skewness, etc. obtained from the histogram can be used as information for determining whether or not digestibility can be determined. We have found that it is possible to determine whether or not the digestibility of sake rice can be determined using the method.
That is, according to the above feature configuration, a histogram-related value selected from among the average value, median value, mode value, kurtosis, and skewness is used as the digestibility determination determination information, and is determined at the same timing as the photographing of sake rice. It is possible to calculate the rate of change in the histogram-related values regarding the state of the sake rice, and to determine whether or not the digestibility of the sake rice can be determined using the digestibility determination information based on the calculated rate of change.

The characteristic structure of the digestibility determination system according to the present invention for achieving the above object is a system for determining the digestibility of sake rice heated in the presence of water,
an optical means for irradiating the sake rice with polarized light;
Photographing means for photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
image data acquisition means for acquiring polarized image data photographed by the photographing means;
histogram creation means for creating a histogram regarding brightness based on the polarization image data;
a rate of change calculation means that acquires digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculates a change rate of the digestibility determination determination information;
Determining the digestibility of the sake rice using the digestibility determination information obtained from the histogram created by the histogram creation means based on the change rate of the digestibility determination information calculated by the change rate calculation means. Digestibility determination determination means for determining whether or not the digestibility can be determined;
Digestibility determination means for determining the digestibility of the sake rice based on the digestibility determination information when the digestibility determination determination means determines that it can be determined;
and a moisture content measuring means for measuring the moisture content of the sake rice at the two or more timings,
The digestibility determination determination information is selected from among the moisture content of the sake rice measured by the moisture content measuring means, and the average value, median value, mode, kurtosis, and skewness obtained from the histogram. At some point, either one of the histogram-related values is selected.

According to the characteristic configuration described above, polarized image data regarding sake rice photographed at at least two or more timings can be acquired, and the acquired polarized image data is processed to create a histogram regarding brightness.
Starches such as amylose and amylopectin contained in sake rice, for example, have a crystal structure in the raw rice state, so polarized images of raw rice have a unique polarized cross that originates from this crystal structure. appears as a high brightness area. On the other hand, in sake rice immediately after steaming, water enters the crystal structure and the crystal structure collapses, so no polarization cross appears in these polarization images. However, in steamed sake rice, water that has entered the crystal structure over time is gradually released to the outside, and the collapsed crystal structure returns one after another (so-called aging), causing these polarized lights to change. A polarized cross appears as a high-brightness area in the image.
As a result of extensive research, the inventor of the present application discovered that digestibility determination information related to the digestibility of sake rice can be obtained from a histogram related to brightness created by processing polarization image data, and this digestibility determination information In addition to obtaining the knowledge that it is possible to determine the digestibility of sake rice based on After calculating the rate of change in the judgment information, based on the calculated rate of change in the digestibility judgment information, we have found that it is possible to judge whether the digestibility judgment information can be used to judge the digestibility of sake rice. As a result, the present invention was completed.
That is, in the characteristic configuration described above, the rate of change calculation means acquires digestibility determination determination information regarding the state of sake rice at two or more timings, and calculates the change rate of the digestibility determination determination information. Then, the digestibility determination determination means determines whether or not the digestibility of the sake rice can be determined using the digestibility determination information, based on the rate of change of the digestibility determination determination information. If the digestibility of the sake rice can be determined, the digestibility of the sake rice can be determined by the digestibility determination means based on the digestibility determination information.
In addition, as a result of extensive research, the inventor of the present application has determined that, in addition to the rate of change in the histogram-related values, as an index for determining whether or not the digestibility of sake rice can be determined using the digestibility determination information. It has been found that the rate of change in moisture content measured at two or more timings can be used.
That is, according to the above characteristic configuration, either the water content measured by the water content measuring means or the histogram-related value selected from the average value, median value, mode, kurtosis, and skewness. is the digestibility determination information, calculate the rate of change in the water content or histogram-related value regarding the state of the sake rice at the same time as the photographing of the sake rice, and based on this calculated rate of change, digestibility determination information is determined. It can be determined whether the digestibility of sake rice can be determined using the following.

In this application, "determining digestibility" is a concept that includes "determining the rate of change (rate of change) of digestibility" and "determining the absolute value of digestibility."

As described above, in the present invention, the digestibility of sake rice can be determined relatively simply and easily without the need for drugs or expensive equipment, and without the need to perform complicated treatments on sake rice.

Further, in a further characteristic configuration of the digestibility determination system according to the present invention, the digestibility determination information is selected from information related to the average value, median value, mode, kurtosis, and skewness obtained from the histogram. The point is that

As a result of extensive research, the inventor of the present application has found that information regarding the average value, median value, mode, kurtosis, and skewness is useful as digestibility determination information obtained from the above-mentioned histogram; We have discovered that the digestibility of sake rice can be determined by using this information as digestibility determination information.

That is, according to the above characteristic configuration, one selected from among those related to the average value, median value, mode, kurtosis, and skewness is used as digestibility determination information, and based on this digestibility determination information, The digestibility of sake rice can be determined.

In this application, "things related to the average value, median value, mode, kurtosis, and skewness" is a concept that includes the rate of change of these values and their absolute values.

Further, in a further characteristic configuration of the digestibility determination system according to the present invention, the optical means includes a light source capable of irradiating light and two polarizers whose crossing angles of polarization axes can be adjusted, The irradiated light passes through one of the two polarizers and is irradiated to the sake rice as polarized light, and the polarized light irradiated to the sake rice is guided to the photographing means through the other polarizer. It is configured so that
Said crossing angle is in a point adjusted within a range of 3° to 180°.

According to the above characteristic configuration, by adjusting the intersection angle of the two polarizers within the range of 3° to 180°, a significant histogram that can be used for determining digestibility can be obtained from the histogram created by processing polarized image data. Digestibility evaluation information can be obtained. The inventor of the present application has determined that when the intersection angle is adjusted within the range of 3° to 180°, the digestibility determination information obtained from the histogram created based on the polarized image data of sake rice, It has been experimentally confirmed that the digestibility of

Further, the characteristic configuration of the digestibility determining method according to the present invention for achieving the above object is a method for determining the digestibility of sake rice heated in the presence of water, comprising:
a polarized light irradiation step of irradiating the sake rice with polarized light;
a photographing step of photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
an image data acquisition step of acquiring polarized image data photographed in the photographing step;
a histogram creation step of creating a histogram regarding brightness based on the polarization image data;
a change rate calculation step of acquiring digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculating a change rate of the digestibility determination determination information;
Determine the digestibility of the sake rice using the digestibility determination information obtained from the histogram created in the histogram creation step based on the change rate of the digestibility determination information calculated in the change rate calculation step. a digestibility determination step of determining whether or not it is possible;
If it is determined that the digestibility can be determined in the digestibility determination determination step, a digestibility determination step is performed in which the digestibility of the sake rice is determined based on the digestibility determination information,
The digestibility determination determination information is a histogram-related value selected from among the average value, median value, mode, kurtosis, and skewness obtained from the histogram.

According to the characteristic configuration described above, polarized image data regarding sake rice taken at at least two or more timings is acquired, the acquired polarized image data is processed to create a histogram regarding brightness, and at least two or more timings are photographed. Digestibility judgment information regarding the state of sake rice is acquired, and a rate of change in this digestibility judgment judgment information is calculated. Then, based on the digestibility determination information, it is determined whether the digestibility of sake rice can be determined using the digestibility determination information obtained from the histogram, and if the digestibility of sake rice can be determined, , the digestibility of sake rice can be determined based on the digestibility determination information.
According to the above feature structure, the histogram-related value selected from the average value, median value, mode, kurtosis, and skewness is used as the digestibility determination determination information, and the sake rice is photographed at the same timing as the sake rice photographing. The rate of change in histogram-related values regarding the state of rice is calculated, and based on the calculated rate of change, it can be determined whether the digestibility of sake rice can be determined using the digestibility determination information.

Further, the characteristic configuration of the digestibility determining method according to the present invention for achieving the above object is a method for determining the digestibility of sake rice heated in the presence of water, comprising:
a polarized light irradiation step of irradiating the sake rice with polarized light;
a photographing step of photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
an image data acquisition step of acquiring polarized image data photographed in the photographing step;
a histogram creation step of creating a histogram regarding brightness based on the polarization image data;
a change rate calculation step of acquiring digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculating a change rate of the digestibility determination determination information;
Determine the digestibility of the sake rice using the digestibility determination information obtained from the histogram created in the histogram creation step based on the change rate of the digestibility determination information calculated in the change rate calculation step. a digestibility determination step of determining whether or not it is possible;
a digestibility determination step of determining the digestibility of the sake rice based on the digestibility determination information when it is determined that the digestibility determination can be determined in the digestibility determination determination step;
carrying out a moisture content measuring step of measuring the moisture content of the sake rice at the two or more timings;
The digestibility determination determination information is selected from among the moisture content of the sake rice measured in the moisture content measurement step, and the average value, median value, mode, kurtosis, and skewness obtained from the histogram. At some point, either one of the histogram-related values is selected.

According to the characteristic configuration described above, polarized image data regarding sake rice taken at at least two or more timings is acquired, the acquired polarized image data is processed to create a histogram regarding brightness, and at least two or more timings are photographed. Digestibility judgment information regarding the state of sake rice is acquired, and a rate of change in this digestibility judgment judgment information is calculated. Then, based on the digestibility determination information, it is determined whether the digestibility of sake rice can be determined using the digestibility determination information obtained from the histogram, and if the digestibility of sake rice can be determined, , the digestibility of sake rice can be determined based on the digestibility determination information.
Further, according to the above feature configuration, either one of the moisture content measured in the moisture content measurement step and a histogram-related value selected from the average value, median value, mode, kurtosis, and skewness. is the digestibility determination information, calculate the rate of change in the water content or histogram-related value regarding the state of the sake rice at the same time as the photographing of the sake rice, and based on this calculated rate of change, digestibility determination information is determined. It can be determined whether the digestibility of sake rice can be determined using the following.

As described above, the method for determining digestibility of sake rice according to the present invention does not require drugs or expensive equipment, and does not require complicated processing of sake rice, and can relatively simply and easily determine the digestibility of sake rice. can be determined.

1 is a diagram showing a schematic configuration of a digestibility determination system according to an embodiment. FIG. 2 is a functional block diagram showing a control device. 1 is a graph summarizing the moisture content of sake rice for Sample 1. 2 is a graph summarizing the moisture content of sake rice for Sample 2. 2 is a graph summarizing the moisture content of sake rice for Sample 3. 2 is a graph summarizing the Brix values of sake rice for Sample 1. 2 is a graph summarizing the Brix values of sake rice for Sample 2. 2 is a graph summarizing the Brix values of sake rice for Sample 3. 2 is a graph summarizing the absolute values of kurtosis of sake rice for Sample 1. 2 is a graph summarizing the absolute values of kurtosis of sake rice for Sample 2. 2 is a graph summarizing the absolute values of kurtosis of sake rice for Sample 3. 2 is a graph showing the relationship between the rate of change in kurtosis and the rate of change in Brix value of sake rice for Samples 1 and 2. 3 is a graph showing the relationship between the absolute value of kurtosis and the Brix value for Sample 1. 7 is a graph showing the relationship between the absolute value of kurtosis and the Brix value for Sample 2. 7 is a graph showing the relationship between the absolute value of kurtosis and the Brix value for Sample 3.

EMBODIMENT OF THE INVENTION Hereinafter, a digestibility determination system and a digestibility determination method according to an embodiment of the present invention will be described with reference to the drawings.

1 and 2 are diagrams showing a schematic configuration of a digestibility determination system 1 according to the present embodiment. As shown in FIG. 1, the digestibility determination system 1 includes an optical device 2 (optical means) that irradiates the sake rice R heated in the presence of water with polarized light, and an optical device 2 (optical means) that irradiates the sake rice R heated with the polarized light. It is equipped with a photographing device 6 (photographing means) that photographs polarized images at at least two or more timings, and a control device 10 that includes various functional units that will be described later.

Further, as shown in FIG. 2, the control device 10 includes an image data acquisition unit 11 (image data acquisition means) that acquires polarized image data photographed by the imaging device 6, and creates a histogram regarding brightness based on the polarized image data. a histogram creation section 13 (histogram creation means), and a change rate calculation section that acquires digestibility determination determination information regarding the state of sake rice R at two or more timings, and calculates a change rate of the digestibility determination determination information. 15 (change rate calculation means) and the rate of change of the digestibility determination information calculated by the change rate calculation unit 15, using the digestibility determination information obtained from the histogram created by the histogram creation unit 13. Digestibility determination determination unit 16 (digestibility determination determination means) that determines whether the digestibility of rice R can be determined, and a digestibility determination unit that determines the digestibility of sake rice based on the digestibility determination information. 18 (digestibility determining means). Further, the control device 10 includes a moisture content measurement unit 14 (moisture content measurement means) that measures the moisture content of sake rice at two or more timings.

Furthermore, the control device 10 includes an image processing unit 12 that processes the polarization image data acquired by the image data acquisition unit 11, and a digestibility determination information acquisition unit that acquires digestibility determination information based on the histogram created by the histogram creation unit 13. The storage unit 17 includes a storage unit 19 in which various types of information to be handled are stored.

In this embodiment, the optical device 2 includes a light 3 (light source) disposed at the lower part of the light-shielding box B, a first polarizing plate 4 (one polarizer) disposed above the light 3, and a light-shielding box B. A second polarizing plate 5 (the other polarizer) is arranged above B. Further, the first polarizing plate 4 and the second polarizing plate 5 are configured such that the angle of each polarizing axis can be adjusted, and in this embodiment, the polarizing axis of the first polarizing plate 4 and the angle of the second polarizing plate 5 are adjustable. The angle of the polarizing axis of the first polarizing plate 4 and/or the second polarizing plate 5 is adjusted so that the angle of intersection with the polarizing axis is within the range of 3° to 180°.

The photographing device 6 is disposed above the second polarizing plate 5 and at a position facing an opening B1 formed at the top of the light-shielding box B.

Therefore, in this embodiment, light is directed upward from the light 3 while the sake rice R whose digestibility is to be determined is placed on the first polarizing plate 4 so as to be located below the opening B1. By irradiating, the irradiated light passes through the first polarizing plate 4 and is irradiated onto the sake rice R as polarized light, and the polarized light irradiated onto the sake rice R passes through the opening B1 and the second polarizing plate 5 and is photographed. A polarized image of the sake rice R is taken by the device 6. That is, in this embodiment, polarized light is irradiated onto the sake rice R, and the transmitted light is observed. The timing at which the photographing device 6 photographs the polarized image of the sake rice is, for example, the timing immediately after the end of heating (the start of aging), and the timing every hour until a certain period of time has passed after the end of heating (one hour after heating, 2 hours later...).

As shown in FIG. 2, the control device 10 includes an image data acquisition section 11, an image processing section 12, a histogram creation section 13, a water content measurement section 14, a rate of change calculation section 15, a digestibility determination determination section 16, and a digestibility determination section 16. It includes a determination information acquisition section 17, a digestibility determination section 18, and a storage section 19.

The image data acquisition unit 11 is a functional unit that acquires polarized image data of the sake rice R photographed by the photographing device 6. Specifically, in this embodiment, a signal related to polarized image data transmitted from the photographing device 6 is received, and polarized image data of the sake rice R is acquired. Note that the polarization image data acquired by the image data acquisition unit 11 is stored in the storage unit 19 as appropriate.

The image processing unit 12 is a functional unit that processes the polarization image data acquired by the image data acquisition unit 11. Specifically, the image processing unit 12 in this embodiment analyzes the polarized sake in the region containing only the sake rice R in the polarized image data acquired by the image data acquisition unit 11 before the histogram creation unit 13 creates a histogram. A process of extracting rice image data and a process of converting the extracted polarized sake rice image data into image data of 256 gradations (grayscale image data) with 255 for bright areas and 0 for dark areas are performed. The above-mentioned processes in the image processing unit 12 are performed to obtain grayscale image data of an area containing only one grain of sake rice, or to obtain grayscale image data of an area containing only one grain of sake rice, or to obtain grayscale image data of an area containing only two or more grains of sake rice (for example, four grains). This is done so that grayscale image data of the area containing the image can be obtained.

The histogram creation unit 13 is a functional unit that creates a histogram regarding brightness based on polarization image data. Specifically, the histogram creation unit 13 in this embodiment creates a luminance-related histogram based on the distribution of gradation values in the grayscale image data obtained by the image processing unit 12 based on the polarization image data.

The moisture content measurement unit 14 is a functional unit that measures the moisture content of the sake rice R at two or more timings. Specifically, the moisture content measuring unit 14 in this embodiment calculates the shape of the sake rice R at the time it was photographed ( By comparing the two-dimensional shape or three-dimensional shape) with the shape of the sake rice before being heated, the moisture content of the sake rice R at the time it was photographed is estimated, and this is taken as the measured moisture content. .

The rate of change calculation unit 15 is a functional unit that acquires digestibility determination determination information regarding the state of sake rice R at two or more timings and calculates a change rate of the digestibility determination determination information. In the present embodiment, the digestibility determination determination information is the moisture content of the sake rice R measured by the moisture content measurement unit 14, or the average value, median value, The histogram-related value is selected from mode, kurtosis, and skewness. Specifically, the rate of change calculation unit 15 in this embodiment uses the water content of the sake rice R at two or more different timings and the histogram-related values obtained from the histograms at two or more different timings to determine whether digestibility can be determined. This information is acquired as judgment information, and the rate of change in water content and the rate of change in histogram-related values are calculated, respectively.

More specifically, the rate of change calculation unit 15 in this embodiment calculates the moisture content (or histogram) at the timing immediately after the end of heating (immediately after the start of aging) (the timing when the sake rice R immediately after heating is placed in the light-shielding box B). (related value) and the moisture content (or histogram related value) at the timing when a predetermined period of time has elapsed since the end of heating (the start of aging) (the timing when a predetermined period of time has elapsed after placing the sake rice R in the light-shielding box B). Then, the rate of change in the water content (or histogram-related value) per hour is calculated as follows. In other words, when the moisture content (or histogram-related value) immediately after the end of heating is _X0 , and the water content (or histogram-related value) at the timing n hours after the end of heating is _Xn , the amount of water per hour is The rate of change Y in water content (or histogram-related value) is calculated using Equation 1.
(Formula 1)
Y=(100×(X ₀ -X _n ))/(n×X ₀ )

In addition, if you want to judge the digestibility at the time when n hours have passed from the end of heating, there are multiple timings until n hours have passed (timings when na, n _b , and n _c hours have passed from the start of aging) _. In cases where the moisture content (or histogram-related values) is obtained, the time from immediately after heating to n _a , n _b , n _c , n is calculated using Equation 1 above for n _a , n _b , n c , and _n, respectively. The rate of change in the water content (or histogram-related value) per hour at the elapsed timing may be calculated, and the average of these may be used as the rate of change in the digestibility determination information.

The digestibility determination determination unit 16 uses the digestibility determination information obtained from the histogram created by the histogram creation unit 13 based on the change rate of the digestibility determination determination information calculated by the change rate calculation unit 15. This is a functional unit that determines whether or not the digestibility of rice R can be determined. Specifically, the digestibility determination determination unit 16 in this embodiment determines at least one of the rate of change in water content per hour calculated by the rate of change calculation unit 15 and the rate of change in histogram-related values per hour. If one of them is less than a predetermined threshold, it is determined that the digestibility of sake rice R can be determined using the digestibility determination information. Note that the thresholds for the rate of change in water content per hour and the rate of change in histogram-related values per hour are set for each intersection angle of the polarization image data that is the basis for obtaining the water content and histogram-related values. For example, when the crossing angle is 90°, the threshold value for the case where the crossing angle is 90°, which is stored in advance in the storage unit 19, is set. In addition, the threshold regarding the rate of change of histogram-related values is a value set for each mean, median, mode, kurtosis, and skewness, and if the histogram-related value is kurtosis, The kurtosis threshold stored in the storage unit 19 is set. The threshold value for the rate of change in moisture content per hour is preferably 12%/h, more preferably 15%/h, and the threshold value for the rate of change in histogram-related values per hour is preferably 25%/h. h, more preferably 30%/h. In addition, these threshold values are determined by obtaining the moisture content (or histogram-related value) every hour from the start of aging until 6 hours have passed, and calculating the moisture content (or histogram-related value) per hour at each timing. ) is calculated and determined based on the average rate of change, but it can be applied as a threshold for the rate of change at any point in time after the start of aging.

The digestibility determination information acquisition unit 17 is a functional unit that acquires digestibility determination information based on the histogram created by the histogram creation unit 13. The digestibility determination information is at least one selected from those related to the average value, median value, mode, kurtosis, and skewness of the histogram. Specifically, in this embodiment, the rate of change of the kurtosis of the histogram and the absolute value of the kurtosis are calculated, and these are acquired as digestibility determination information.

The digestibility determining unit 18 is a functional unit that determines the digestibility of the sake rice R based on the digestibility determining information obtained from the histogram created by the histogram creating unit 13. Specifically, the digestibility determination unit 18 of the present embodiment uses a predetermined digestibility value corresponding to the kurtosis-related value (the rate of change of kurtosis or the absolute value of kurtosis) acquired by the digestibility determination information acquisition unit 17. The digestibility of sake rice R is determined based on the correlation between sex determination information and digestibility, weighting coefficients, etc. More specifically, for example, the polarization image data that was the basis for creating the histogram was taken with the intersection angle adjusted to 90°, and the kurtosis obtained from the histogram and the value immediately after heating were When the rate of change in kurtosis calculated based on the kurtosis obtained from the histogram created from polarized image data is used as digestibility determination information, the rate of change in kurtosis and the rate of change in kurtosis when the intersection angle is 90° are The rate of change in digestibility of sake rice R is determined based on the correlation between the predetermined rate of change in kurtosis and the rate of change in digestibility. In addition, when the absolute value of kurtosis obtained from the histogram is used as digestibility determination information, the absolute value of kurtosis and the absolute value of digestibility determined in advance when the intersection angle is 90° with this absolute value of kurtosis. The absolute value of digestibility of sake rice R is determined based on the correlation with Note that, if necessary, the digestibility (rate of change in digestibility or absolute value of digestibility) of sake rice R may be determined based on the correlation and the weighting coefficient regarding this correlation.

In addition, the digestibility determination unit 18 in this embodiment determines whether the digestibility of the sake rice R is digestible when the digestibility determination determination unit 16 determines that the digestibility of the sake rice R cannot be determined using the digestibility determination information. It is determined that the digestibility has not changed since immediately after the end of heating (that is, the rate of change is zero) or that the absolute value of digestibility is the same as that immediately after the end of heating. The absolute value of digestibility of sake rice R immediately after heating can be obtained by the following method. For example, it can be inferred from brightness information obtained from a polarized image taken of the sake rice R immediately after heating (for example, the average brightness of a polarized image taken with the intersection angle adjusted to 3°). More specifically, the average brightness is obtained from the polarized image of sake rice R immediately after heating, and based on the correlation between this average degree and the predetermined average brightness and digestibility, Estimate the absolute value of digestibility of rice R. Alternatively, sake rice immediately after heating may be reacted with an enzyme, the amount of decomposed sugar (Brix value) may be measured, and this Brix value may be used as the absolute value of digestibility.

The storage unit 19 is a functional unit that stores various types of information to be handled, and in this embodiment, a threshold value for the rate of change in water content, a threshold value for the rate of change in histogram-related values, predetermined digestibility determination information, and digestibility information. In addition to the correlation with It is possible to store the information obtained and calculated (moisture content, histogram-related values, rate of change of these, digestibility judgment information, etc.).

Next, a method for determining the digestibility of sake rice R using the digestibility determining system 1 having the above configuration will be described.

First, the sake rice R immediately after heating is placed in a Petri dish placed on the first polarizing plate 4 in the light-shielding box B, and then the polarizing axis of the first polarizing plate 4 and the polarizing axis of the second polarizing plate 5 are placed. The position of each polarizing plate 4, 5 is adjusted so that the angle of intersection with the polarizing plate is an arbitrary angle between 3° and 180°. In the following, an example will be described in which the positions of the polarizing plates 4 and 5 are adjusted so that the intersection angle is 90°.

Next, the light irradiation from the light 3 is started, and the polarized light that has passed through the first polarizing plate 4 is irradiated onto the sake rice R (polarized light irradiation step), and the sake rice R is irradiated with the polarized light. The photographing device 6 photographs a polarized image of the sake rice R immediately after heating and a polarized image of the sake rice R after a predetermined period of time has elapsed from the end of heating (photographing step).

Next, the polarized image of the sake rice R photographed by the photographing device 6 is acquired by the image data acquisition section 11 (image data acquisition step), and the image processing section 12 processes the acquired polarized image data to include only the sake rice R. Polarized sake rice image data of the region is extracted, and the extracted polarized sake rice image data is converted into grayscale image data (image conversion step). Thereafter, the histogram creation unit 13 creates a distribution diagram of tone values (a histogram regarding brightness) in the grayscale image data obtained by processing the polarized image data (histogram creation step).

Next, in the moisture content measurement unit 14, based on the grayscale image data, the shape of the sake rice R before heating, the shape of the sake rice R immediately after heating, and the shape of sake rice R after a predetermined period of time from the end of heating are determined. By comparing the shape of sake rice R, the moisture content of sake rice R immediately after heating and the moisture content of sake rice R after a predetermined period of time have passed from the end of heating are estimated, and this is compared with the measured moisture content. (moisture content measurement process).

Thereafter, in the rate of change calculation unit 15, the moisture content of the sake rice R measured in the moisture content measuring step immediately after the end of heating and at the timing when a predetermined period of time has passed since the end of heating, the polarized image data taken immediately after the end of heating, and the A histogram-related value obtained from a histogram created based on each piece of polarization image data taken at a timing when a predetermined period of time has elapsed from the end of heating is acquired as digestibility determination determination information. Then, the rate of change calculation unit 15 calculates the rate of change in the water content per hour and the rate of change in the histogram-related value per hour based on Equation 1 (change rate calculation step).

Next, in the digestibility determination determination unit 16, if either the rate of change in water content calculated in the change rate calculation step or the rate of change in histogram-related values is less than a predetermined threshold, the digestibility It is determined that the digestibility of sake rice R can be determined using the determination information, and if it is equal to or higher than the threshold value, it is determined that the digestibility of sake rice R cannot be determined using the digestibility determination information (digestibility determination (probability judgment process).

In addition, the digestibility determination information acquisition unit 17 calculates values regarding the average value, median value, mode, kurtosis, and skewness based on the histogram created in the histogram creation step (digestibility determination information acquisition process).

After that, if it is determined in the digestibility determination determination step that the digestibility of sake rice R can be determined using the digestibility determination information, the digestibility determination section 18 acquires the digestibility determination information in the digestibility determination information acquisition step. The correlation between predetermined digestibility determination information (rate of change of kurtosis and absolute value of kurtosis) and digestibility (rate of change of kurtosis and digestibility when the intersection angle is 90°) The digestibility of sake rice R (the correlation between the rate of change in digestibility and the correlation between the absolute value of kurtosis and the absolute value of digestibility) and the weighting coefficient related to this correlation is calculated based on the and the absolute value of digestibility) (digestibility determination step). Note that if the digestibility determination determination unit 16 determines that the digestibility of the sake rice R cannot be determined using the digestibility determination information, the digestibility of the sake rice R has not changed since immediately after the end of heating. (The rate of change is zero) or it is determined that the absolute value of digestibility is the same as that immediately after heating.

As described above, according to the digestibility determination system and digestibility determination method according to the present embodiment, a polarized image of sake rice R is photographed, and the rate of change in the moisture content of sake rice R and the polarized light are determined based on the polarized image data. The rate of change in histogram-related values is calculated from a histogram created based on image data, and based on the calculated rate of change in moisture content and rate of change in histogram-related values, digestibility judgment information obtained from the histogram is calculated. Determine whether digestibility can be determined. If it is determined that digestibility can be determined, digestibility (rate of change in digestibility and absolute value of digestibility) is determined based on the digestibility determination information (rate of change in kurtosis and absolute value of kurtosis). can be determined. Therefore, the digestibility of sake rice R can be determined relatively simply and easily without the need for drugs, expensive equipment, or complicated treatments for sake rice R.

In addition, when the rate of change in digestibility is determined as the digestibility of sake rice R using the digestibility determination system and digestibility determination method according to the present embodiment, the rate of change in digestibility is determined based on the determined rate of change in digestibility. It is also possible to estimate what the absolute value of the digestibility of sake rice R will be when it is aged for a predetermined period of time after the completion of aging.

Hereinafter, an experiment conducted to confirm that digestibility can be determined by the digestibility determination system and digestibility determination method according to the present invention will be described.

[Sample preparation]
Three samples of sake rice were prepared by soaking a plurality of sake rice in water and allowing it to absorb water for 60 minutes, then steaming it for 45 minutes.
These three samples were aged under different conditions as shown in Table 1 from immediately after steaming until 6 hours had passed. Sample 1 was aged at a temperature of 15° C. and a humidity of 60% while blowing air at a speed of 0.5 to 1 m/s. Further, Sample 2 was aged at a temperature of 15° C. and a humidity of 100% without being exposed to air. Further, Sample 3 was aged at a temperature of 15° C. and a humidity of 60% while blowing air at a speed of 2 m/s.
For these samples 1 to 3, the sake rice was taken out every hour from immediately after steaming until 6 hours had elapsed, and the moisture content and digestibility test were conducted. In the following description, the timing immediately after steaming is referred to as "aging 0h", and the hourly timings until 6 hours have passed from immediately after steaming are referred to as "aging 1h" to "aging 6h".
In addition, polarization images were taken for each sample from aging 0h to aging 6h, and the rate of change in kurtosis and the absolute value of kurtosis were calculated from the histogram created based on the polarization image data, and information regarding the calculated kurtosis ( The relationship between the rate of change in kurtosis and the absolute value of kurtosis) and the results of the digestibility test (rate of change in digestibility and absolute value of digestibility) was verified.
Furthermore, conditions under which digestibility (rate of change in digestibility and absolute value of digestibility) can be determined based on the correlation between information on kurtosis and digestibility (rate of change in digestibility and absolute value of digestibility) was verified.

[Moisture content measurement]
A plurality of sake rice was taken out from each sample and placed in a constant temperature bath adjusted to a temperature of 135° C. for 1 hour to be baked. The weight of the sake rice before and after firing was measured, and the moisture content of the sake rice in each sample was calculated from the weight change. The test was conducted twice, and the average value was calculated. 3 to 5 are graphs summarizing the moisture content of sake rice from aging 0 hours to aging 6 hours, with FIG. 3 relating to sample 1, FIG. 4 relating to sample 2, and FIG. 5 relating to sample 3.

As shown in Figures 3 to 5, the way the moisture content changes varies greatly depending on the environment in which sake rice is aged. Comparing samples 1 and 3 with sample 2, sample 2 aged in a high humidity environment has almost no change in moisture content, whereas sample aged in a relatively low humidity environment In samples 1 and 3, the moisture content decreased over time.

[Digestibility test]
Digestibility is an index that expresses the ease with which sake rice is broken down by enzymes, so by reacting sake rice with enzymes and measuring the amount of decomposed sugar (Brix value), this Brix value can be calculated as an indicator of digestibility. It can be used as an indicator.
First, a 0.1M succinate solution and a 0.1M sodium succinate solution were mixed to prepare a 0.1M succinate buffer solution with a pH of 4.3. Next, this succinate buffer solution was mixed to contain α-amylase at 60 u/mL and protease at 3000 u/mL to obtain an enzyme buffer solution.
Next, 10 g of sake rice was taken out from each sample, 50 mL of enzyme buffer was added to the taken out sake rice, and after shaking vigorously for 10 seconds, the rice was allowed to stand at 15° C. for 24 hours to perform digestion. Additionally, 0.5 mL of toluene was added as a preservative if necessary.
After digestion, the digestive fluid was centrifuged to obtain a filtrate, and the Brix value of this filtrate was measured. The Brix value was measured three times and the average value was calculated. In addition, the rate of change in Brix value (rate of change in digestibility) is calculated based on the Brix value of sake rice at 0 h of aging and the Brix value at a predetermined time after aging (1 h of aging, 3 hours of aging, 6 hours of aging). did.
Figures 6 to 8 are graphs summarizing the Brix values of sake rice at 0h aging, 3h aging, and 6h aging, where Figure 6 is for sample 1, Figure 7 is for sample 2, and Figure 8 is for sample 3. .

As shown in FIGS. 6 to 8, there was a large difference between Samples 1 and 2 and Sample 3 in the way the Brix value changed. That is, in Samples 1 and 2, the Brix value gradually decreased over time, and the digestibility gradually decreased as aging progressed. On the other hand, in sample 3, there is almost no change in the Brix value over time, and no significant change in digestibility is observed even with advancing aging. This is thought to be because the water was evaporated while the crystal structure maintained immediately after steaming due to aging while exposed to high-velocity wind.

[Calculation of digestibility determination information]
Using the digestibility determination system according to the above embodiment, each sample was sampled at the timing of aging 0h to aging 6h for each case where the crossing angle of the polarization axes of the two polarizing plates was 90° and 135°. A polarized image of the sake rice taken out was taken, the obtained polarized image data was processed to create a histogram, and the absolute value of kurtosis was calculated. Figures 9 to 11 are graphs summarizing the absolute values of kurtosis of sake rice from aging 0h to aging 6h, with Figure 9 relating to sample 1, Figure 10 relating to sample 2, and Figure 11 relating to sample 3. .
Furthermore, the rate of change in kurtosis was calculated based on the absolute value of kurtosis at the timing of aging 0h and the absolute value of kurtosis at the time when a predetermined period of time has passed after aging (aging 1h, aging 3h, aging 6h).

[Verification of the relationship between digestibility determination information and digestibility]
FIG. 12 is a graph showing the relationship between the rate of change in kurtosis calculated above and the rate of change in Brix value calculated based on the results of the digestibility test for Samples 1 and 2. Figures 13 to 15 also show the absolute value of kurtosis calculated from a histogram created based on a polarization image taken by adjusting the crossing angle of the polarization axes of two polarizers to 90° for each sample, and the 13 is a graph showing the relationship with the results of a sex test (Brix value as an absolute value of digestibility); FIG. 13 is for Sample 1, FIG. 14 is for Sample 2, and FIG. 15 is for Sample 3. Table 2 is a table summarizing the correlation coefficients obtained from the graphs shown in FIGS. 13 to 15 and the presence or absence of correlation determined based on the correlation coefficients. Furthermore, Table 3 shows the relationship between the absolute value of kurtosis calculated from a histogram created based on a polarization image taken by adjusting the crossing angle of the polarization axes of two polarizing plates to 135° and the digestibility test results. This is a table summarizing the correlation coefficients obtained from the above and the presence or absence of correlation determined based on the correlation coefficients.

As can be seen from FIG. 12, for Samples 1 and 2, the rate of change in kurtosis calculated based on the absolute value of kurtosis obtained from the histogram when the intersection angle is adjusted to 90° is different from the rate of change in digestibility. There is a high correlation between them (correlation coefficient 0.86). From this, it was confirmed that the rate of change in digestibility of sake rice can be determined using the rate of change in kurtosis as digestibility determination information.
In addition, as can be seen from Figures 13 to 15 and Table 2, for Samples 1 and 2, the absolute value of kurtosis and digestibility (Brix value) obtained from the histogram when the intersection angle was adjusted to 90° There is a high correlation between Furthermore, as can be seen from Table 3, for Samples 1 and 2, there is a high correlation between the absolute value of kurtosis obtained from the histogram and digestibility (Brix value) when the intersection angle is adjusted to 135°. be. From this, unless the water evaporates while maintaining the crystal structure immediately after steaming, as in Sample 3, the absolute value of kurtosis can be used as digestibility judgment information to determine the absolute digestibility of sake rice. It was confirmed that the value could be determined.

[Verification of conditions for determining digestibility]
We verified the conditions for determining the digestibility of sake rice using digestibility determination information. Table 4 shows the changes in the moisture content of sake rice per hour from aging 1h to aging 6h based on the moisture content of sake rice from aging 1h to aging 6h in each sample shown in Figures 3 to 5. Each rate was calculated using Formula 1, and the average value is shown. Table 4 also shows the kurtosis of sake rice per hour from aging 1h to aging 6h based on the kurtosis of sake rice from aging 1h to aging 6h in each sample shown in Figures 9 to 11. The rate of change in degree was calculated using Formula 1, and the average value is shown.

Table 4 shows that there are differences in the rate of change in water content and rate of change in kurtosis for each sample, and the rate of change is particularly large in sample 3, where water is thought to have evaporated while maintaining the crystal structure immediately after steaming. ing. The differences in the rate of change in moisture content and the rate of change in kurtosis among the samples are considered to be caused by the rapid decrease in moisture in sake rice during the aging process. Therefore, based on the rate of change in moisture content and the rate of change in kurtosis, we can show the correlation between moisture content and digestibility and the correlation between kurtosis and digestibility, as in Samples 1 and 2. A clear distinction can be made between cases where these correlations are not shown and cases where these correlations are not shown, such as in sample 3. Therefore, for sake rice that shows a correlation between water content and digestibility, or a correlation between kurtosis and digestibility, it is possible to judge the digestibility of sake rice using digestibility judgment information. It can be determined that

As described above, based on the rate of change in the measured moisture content and the rate of change in histogram-related values obtained from the histogram, it is determined whether digestibility can be determined using the digestibility determination information, and the digestibility is determined. If it is determined that the digestibility can be determined, it was confirmed that the digestibility can be determined based on the digestibility determination information.

[Another embodiment]
[1] In the above embodiment, the moisture content measurement unit 14 is provided, and either the rate of change in moisture content or the rate of change in histogram-related values is adopted as information for determining whether digestibility can be determined, and the digestibility determination information is used. Although the present invention has been described as an embodiment in which it is determined whether or not the digestibility of sake rice can be determined by using the method, the present invention is not limited to this. The digestibility determination system 1 may be configured without the moisture content measuring section 14, and only the rate of change of the histogram-related values may be used as the digestibility determination determination information.

[2] In the above embodiment, the moisture content measurement unit 14 estimates the moisture content of sake rice based on grayscale image data, and uses this as the measured moisture content, but the present invention is not limited to this. isn't it. For example, the moisture content of sake rice may be measured using a known method.

[3] In the above embodiment, the intersecting angle of the polarization axes of the two polarizing plates is adjusted within the range of 3° to 180°, but this is not limited to this, and significant digestibility determination information can be used. From the viewpoint of obtaining the following, it is preferable to adjust the crossing angle of the polarization axes of the two polarizing plates within the range of 50° to 150°.

[4] In the above embodiment, polarized light is irradiated onto the sake rice and the transmitted light is observed, but the invention is not limited to this. It may be configured such that the reflected light from the brewed rice is guided to a photographing device, and a polarized image of the sake rice is photographed, that is, the reflected light is observed.

[5] In the above embodiment, polarized sake rice image data is extracted from polarized image data taken with a photographing device, and the extracted polarized sake rice image data is converted into grayscale image data. It is not limited. After converting the polarized image data to gray scale, the image data of the area containing only sake rice may be extracted, and if necessary, the polarized image data may be It is only necessary to perform appropriate processing.

[6] In the above embodiments, the digestibility determination information is selected from among those related to the average value, median value, mode, kurtosis, and skewness. The information is not particularly limited as long as it can be obtained from the histogram, and information other than the above-mentioned average value, median value, mode, kurtosis, and skewness may be used.

The configurations disclosed in the above embodiments (including other embodiments) can be applied in combination with the configurations disclosed in other embodiments as long as there is no contradiction, and the configurations disclosed in this specification can also be applied in combination with configurations disclosed in other embodiments. The embodiments described above are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the purpose of the present invention.

INDUSTRIAL APPLICATION This invention can be utilized for the digestibility determination system and digestibility determination method which can determine the digestibility of sake rice heated in the presence of water.

1 Digestibility determination system 2 Optical device (optical means)
3 Light (light source)
4 First polarizing plate (one polarizer)
5 Second polarizing plate (other polarizing body)
6 Photography device (photography means)
11 Image data acquisition unit (image data acquisition means)
13 Histogram creation section (histogram creation means)
14 Moisture content measuring section (moisture content measuring means)
15 Change rate calculation unit (change rate calculation means)
16 Digestibility determination determination unit (digestibility determination determination means)
18 Digestibility determination unit (digestibility determination means)

Claims (6)

A system for determining the digestibility of sake rice heated in the presence of water, the system comprising:
an optical means for irradiating the sake rice with polarized light;
Photographing means for photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
image data acquisition means for acquiring polarized image data photographed by the photographing means;
histogram creation means for creating a histogram regarding brightness based on the polarization image data;
a rate of change calculation means that acquires digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculates a change rate of the digestibility determination determination information;
Determining the digestibility of the sake rice using the digestibility determination information obtained from the histogram created by the histogram creation means based on the change rate of the digestibility determination information calculated by the change rate calculation means. Digestibility determination determination means for determining whether or not the digestibility can be determined;
digestibility determination means for determining the digestibility of the sake rice based on the digestibility determination information when the digestibility determination determination means determines that it can be determined ;
The digestibility determination system is characterized in that the digestibility determination determination information is a histogram-related value selected from among the average value, median value, mode, kurtosis, and skewness obtained from the histogram. A system for determining the digestibility of sake rice heated in the presence of water, the system comprising:
an optical means for irradiating the sake rice with polarized light;
Photographing means for photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
image data acquisition means for acquiring polarized image data photographed by the photographing means;
histogram creation means for creating a histogram regarding brightness based on the polarization image data;
a rate of change calculation means that acquires digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculates a change rate of the digestibility determination determination information;
Determining the digestibility of the sake rice using the digestibility determination information obtained from the histogram created by the histogram creation means based on the change rate of the digestibility determination information calculated by the change rate calculation means. Digestibility determination determination means for determining whether or not the digestibility can be determined;
Digestibility determination means for determining the digestibility of the sake rice based on the digestibility determination information when the digestibility determination determination means determines that it can be determined;
and a moisture content measuring means for measuring the moisture content of the sake rice at the two or more timings,
The digestibility determination determination information is selected from among the moisture content of the sake rice measured by the moisture content measuring means, and the average value, median value, mode, kurtosis, and skewness obtained from the histogram. A digestibility determination system that is one of selected histogram-related values. 3. The digestibility determination system according to claim 1 , wherein the digestibility determination information is selected from information related to the average value, median value, mode, kurtosis, and skewness obtained from the histogram. The optical means includes a light source capable of emitting light and two polarizers whose intersecting angle of polarization axes can be adjusted, and the light emitted from the light source is directed to one of the two polarizers. through which the sake rice is irradiated as polarized light, and the polarized light irradiated onto the sake rice is guided to the photographing means through the other polarizer,
The digestibility determination system according to any one of claims 1 to 3 , wherein the crossing angle is adjusted within a range of 3° to 180°. A method for determining the digestibility of sake rice heated in the presence of water, the method comprising:
a polarized light irradiation step of irradiating the sake rice with polarized light;
a photographing step of photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
an image data acquisition step of acquiring polarized image data photographed in the photographing step;
a histogram creation step of creating a histogram regarding brightness based on the polarization image data;
a change rate calculation step of acquiring digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculating a change rate of the digestibility determination determination information;
Determine the digestibility of the sake rice using the digestibility determination information obtained from the histogram created in the histogram creation step based on the change rate of the digestibility determination information calculated in the change rate calculation step. a digestibility determination step of determining whether or not it is possible;
If it is determined that the digestibility can be determined in the digestibility determination determination step, a digestibility determination step is performed in which the digestibility of the sake rice is determined based on the digestibility determination information ,
The digestibility determination method is characterized in that the digestibility determination determination information is a histogram-related value selected from among the average value, median value, mode, kurtosis, and skewness obtained from the histogram. A method for determining the digestibility of sake rice heated in the presence of water, the method comprising:
a polarized light irradiation step of irradiating the sake rice with polarized light;
a photographing step of photographing polarized images of the sake rice irradiated with the polarized light at at least two or more timings;
an image data acquisition step of acquiring polarized image data photographed in the photographing step;
a histogram creation step of creating a histogram regarding brightness based on the polarization image data;
a change rate calculation step of acquiring digestibility determination determination information regarding the state of the sake rice at the two or more timings, and calculating a change rate of the digestibility determination determination information;
Determine the digestibility of the sake rice using the digestibility determination information obtained from the histogram created in the histogram creation step based on the change rate of the digestibility determination information calculated in the change rate calculation step. a digestibility determination step of determining whether or not it is possible;
a digestibility determination step of determining the digestibility of the sake rice based on the digestibility determination information when it is determined that the digestibility determination can be determined in the digestibility determination determination step;
carrying out a moisture content measuring step of measuring the moisture content of the sake rice at the two or more timings;
The digestibility determination determination information is selected from among the moisture content of the sake rice measured in the moisture content measurement step, and the average value, median value, mode, kurtosis, and skewness obtained from the histogram. A digestibility determination method that is one of the selected histogram-related values.

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