JPH07104277B2 - Rice texture evaluation method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a taste evaluation method for comprehensively evaluating the taste of rice, and more specifically, the content of a predetermined component affecting the taste contained in rice is measured. The present invention relates to a method and an apparatus for comprehensively evaluating the taste of rice based on the measured values.

[Conventional technology and its problems]

The taste of rice varies depending on the production stage such as variety, place of production, cultivation method, and harvesting method, the processing stage after harvesting such as drying, storage, and rice polishing processing, and the one determined by cooking rice. However, it is the production stage, and then the processing stage, that the taste of rice is most affected.

Conventionally, a comprehensive evaluation of the taste of rice has been performed by a plurality of specialized examiners of cooked rice in terms of appearance, aroma, and
Each comparison item such as taste, stickiness, and hardness is repeatedly compared with those of the standard rice used as the evaluation standard to see how superior or inferior it is, and the average value is taken and summarized together. By the so-called sensory test. However, since this sensory test is performed based on the taste that varies from person to person, even if an average of multiple evaluation results by multiple examiners is taken, the evaluation value changes at different times and different places. However, it cannot be said that the value is constant and objective. Moreover, the composition and physicochemical properties of rice are scientifically measured and analyzed, and the correlation with the comprehensive evaluation value of the taste obtained by the sensory test is investigated, and finally the measurement obtained scientifically. Studies have been conducted to try to comprehensively evaluate the taste of rice from the value. As a result, among the components that make up rice, the ones that are particularly important for comprehensively evaluating the taste of rice are the content ratios of amylose and amylopectin, the protein content ratio, and the water content ratio that compose rice starch. It has been found.

Next, it will be explained how the content of each component of rice affects the taste of rice.

Generally, the most popular rice brands in Japan are Koshihikari and Sasanishiki. As an example, comparing the content ratio of protein contained in white rice of each standard milling degree of several brands of rice including Koshihikari and Sasanishiki and the content ratio of amylose in starch, as shown in Table 1 below. Become. In addition, the content rate of each component is not always the same as shown in the table if it is the same brand, and depending on the geological conditions (soil, water quality) of the cultivated production area, the weather conditions (temperature, sunshine duration) Needless to say, the content rate of each component also changes slightly depending on the amount of rainfall.

From Table 1 above, the main factors that make Koshihikari and Sasanishiki tasty are that the content of protein is low and the content of amylose in starch is low compared to other common brand rice. I understand.

As mentioned above, apart from the fact that the protein content and the amylose content in the starch have a great influence on the taste of rice, the moisture content of white rice also affects the taste in relation to the viscosity and hardness of rice when cooking rice. Have a big impact. Water content of white rice is 15%
In the case of rice, even if it is immersed in water in the pot during rice cooking, cracks do not occur in the white rice and it is cooked into complete rice grains, but in the case of white rice with a moisture content below 14%, the water absorption rate during immersion is high. If it passes too quickly, a crack will occur in the rice grain, and soon a through crack will occur in the inside of the rice grain, so water will be absorbed in the crack and the glue will drain from the crack. Since the cooked rice is crumbled, the cooked rice will be chewy and sticky with low taste. The moisture content of white rice is 14
It can be said that the main reason for dividing the percentage is the excessive drying in the processing stage after the rice is harvested, especially in the drying work, and the subsequent generation of broken rice in the rice polishing work and the drying accompanying frictional heat generation.
Therefore, in order to prevent white rice from having a water content of less than 14% and having a reduced eating quality, it is necessary to operate the dryer to prevent over-drying in the drying operation, and in the rice polishing operation, the It is necessary to control and adjust the rice milling machine so that the generation of broken rice due to wear or the like or the excessive drying due to frictional heat generation is not induced.

It should be noted that, in addition to the contents of the above-mentioned components of rice, which have a great influence on the taste of rice, that is, the contents of protein, starch, and water, the content of fats and fatty acids is small, and the lower the content, the better the taste of rice. As described above, the taste of rice is affected, but it can be said that the degree of the influence is not as great as the content of the three components.

Normally, it is difficult to secure a large amount of only single-brand rice with a good taste at rice mills, so there are several types or brands of rice with different tastes, for example, top-ranked rice and low-ranked rice in taste evaluation. By mixing and milling rice, and adjusting the mixing ratio appropriately, we are trying to distribute polished rice with a stable taste. However, the selection of several types of rice to be mixed and the determination of the mixing ratio are actually processed based on intuition based on the data surveyed in the past, and there is no scientific support at all, In many cases, it was not possible to obtain polished rice with a stable taste as desired, and consumers often complained.

On the other hand, it has been conventionally empirically known that when rice is cooked by adding a small amount of sticky rice to nonglutinous rice (general white rice), the viscosity of the cooked rice is improved and the taste is improved. The following can be said in terms of relationships. The starch quality is composed of amylose and amylopectin, and when the content ratio of amylose in the starch quality increases, the taste of rice tends to decrease as described in relation to Table 1 above. Therefore, if general rice cake having amylopectin content in starch of about 78% is added to rice by adding a small amount of sticky rice having amylopectin content of about 100%, the amylopectin content is high, The taste is improved almost as much as that of rice with a low amylose content. However, when the amylopectin content ratio exceeds a certain level, the viscosity becomes too strong and the taste of cooked rice is adversely deteriorated.

From the above, it is possible to objectively perform a comprehensive evaluation of the taste of rice by scientifically measuring and analyzing the chemical constituents that make up the rice, and to identify specific famous brands that are generally said to have a good taste. The theme is to find good-tasting rice from general-brand rice, and to improve the taste of rice by mixing multiple kinds of rice with different brands or different ingredient contents.

In view of the above, the present invention measures the content of a plurality of predetermined components that affect the taste of rice in a short time, and based on the measured value and a specific coefficient for taste evaluation set corresponding to the components. , Which can calculate and display an evaluation value corresponding to the comprehensive evaluation value of rice taste, which has been conventionally obtained by a sensory test based on each comparison item such as appearance, aroma, taste, stickiness, and hardness of rice. It is a technical object to provide a method and an apparatus for evaluating the taste of food.

[Means for solving problems]

According to the present invention, a component conversion coefficient is determined from the relationship between the content of a plurality of predetermined components that affect the taste of rice and the absorbance when the rice is irradiated with near-infrared light. A specific coefficient is determined from the relationship between the content rate of the ingredients and the comprehensive evaluation value of the taste of rice obtained by sensory evaluation, and the absorbance is measured by irradiating it with near infrared light without heat or chemical treatment of the sample rice. The content of the plurality of predetermined components in the sample rice is determined from the measured absorbance and the component conversion coefficient, and then the comprehensive evaluation value of the taste of the sample rice is obtained from the content and the specific coefficient. In the taste evaluation method, there is provided a taste evaluation method for rice, which comprises polishing the sample rice to a substantially constant degree of whiteness, and then measuring the absorbance of near-infrared light by the sample rice.

According to the present invention, further, for the sample rice, a device for performing a comprehensive evaluation of the taste by measuring a plurality of predetermined components that affect the taste of rice without heat treatment or chemical treatment,
The component analysis device and the control device are provided, and the component analysis device has means for measuring and outputting the absorbance of near-infrared light by the sample rice, and the control device has the content ratio of the plurality of predetermined components and the near-infrared light to the rice. The component conversion coefficient determined from the relationship with its absorbance when irradiated with and the specific coefficient determined from the relationship between the content ratio of the plurality of predetermined components in rice and the comprehensive evaluation value of the rice taste obtained by sensory In the rice taste evaluation apparatus having the storage means and the calculating means for calculating and outputting the comprehensive evaluation value of the taste based on the absorbance of the sample rice, the component conversion coefficient and the specific coefficient, the sample rice has a substantially constant whiteness. An apparatus for evaluating the taste of rice is provided, which is equipped with a rice-polishing device for pearling so that

[Action]

When different sample rices are respectively irradiated with near infrared light, wavelengths at which the contents of the constituents of rice are remarkably expressed as a difference in absorbance of near infrared light are observed.

The present invention utilizes this absorbance characteristic to accurately measure the component content using a detection signal from a detector for measuring the difference in absorbance and the content of the component to be measured in advance, for example, using a chemical quantitative analysis method. Component conversion coefficient calculated by multiple regression analysis method of the relationship between the component content of many rice and absorbance, and the comprehensive evaluation value of the taste of many rice obtained by sensory test in advance for calculating the taste evaluation value Based on the specific coefficient obtained by calculating the relationship with the ingredient content by the multiple regression analysis method, calculate the content rate of the ingredient to be measured and the overall evaluation value of the taste of the sample rice milled to a certain degree of milling. It is something to display.

Example of Invention

Hereinafter, the apparatus and working method used in the present invention will be described with reference to FIGS. 1 to 7.

FIG. 1 is a schematic view of a rice taste evaluation apparatus 1 according to the present invention when viewed from the front. Inside the cabinet 2, a near-infrared spectroscopic analysis device 3 and a control device 4 which are described in detail with reference to FIG. On the front panel of the cabinet 2, a light emitting diode or CRT type display device 6 for visually displaying the operation procedure of the device, calculation results, etc., a push button 7 for operation, and a printer 8 capable of making a hard copy of the calculation results are provided. To be done. The control device 4 is connected to the near-infrared spectroscopic analysis device 3, the display device 6, the operation push button 7, the printer 8 and the like, and an input / output signal processing device 4a for processing various signals, and calculates the content rate of each component. Ingredient conversion coefficient to do, specific coefficient set individually for each major ingredient of rice to calculate the taste evaluation value,
A storage device 4b for storing the US price, various correction values, various control procedures, etc. for each brand or grade input via the input device (keyboard) 9, and a near infrared spectroscopic analysis device 3
And a calculation device 4c for calculating a rice taste evaluation value and the like based on the measurement value obtained by the above and the specific coefficient. It should be noted that the specific coefficient and the necessary correction value that are individually set for each main component of rice are stored in advance in the read-only memory (hereinafter, referred to as ROM) in the storage device 4b, and the taste evaluation device 1 The keyboard 9 as an input device is not always necessary when the required function is simply to obtain the taste evaluation value of rice and the function to obtain the optimum mixing ratio based on various setting conditions is not required. Further, the printer 8 is not limited to the built-in type, and may be the external connection type.

A supply hopper 10 for introducing sample rice is mounted on the upper part of the cabinet 2, and a rice polishing apparatus 11 for connecting the lower end of the supply hopper 10 and polishing the sample rice is provided. Rice milling equipment 11
Below the table is a sample crusher that crushes the sample rice into fine particles.
12 is provided, and below the sample crushing device 12, a sample rice transporting device 14 for moving the sample container 13 (see FIG. 2) to a position directly below the measuring section of the near-infrared spectroscopic analyzer 3. A supply device is provided.

Reference numeral 15 denotes an unnecessary sample rice after the sample rice crushed by the sample crushing device is filled in the sample container 13 in a necessary amount, and a receiving box for receiving the sample discharged after the measurement is completed. Can be removed from the front panel of the.
Further, reference numeral 16 is an external supply unit when the sample rice is independently supplied to the measuring unit from the outside.

FIG. 2 is a cross-sectional view of a main part of one embodiment of the near-infrared spectroscopic analyzer 3 arranged inside the cabinet 2. The illustrated near-infrared spectroscopic analyzer 3 is of a reflection type, and has a light source 17, a reflecting mirror 18, a narrow band pass filter 19, an integrating sphere 20, and detectors 21a and 21b as main components. Light source 17
The near-infrared light emitted from the and converted into parallel rays through an appropriate optical system (not shown) becomes near-infrared monochromatic light of a specific wavelength by passing through the narrow band pass filter 19,
Reflecting mirror 18 configured to change the tilt angle freely
The lighting window 22 provided by opening the upper part of the integrating sphere 20
Redirected towards. Thus, the near-infrared monochromatic light entering the integrating sphere 20 is directly above the sample rice 24 in the sample container 13 from the measuring unit 23 (see FIG. 3) provided by opening the bottom of the integrating sphere 20. Is irradiated from. The diffusely reflected light from the sample rice 24 is reflected on the inner wall of the integrating sphere 20 and finally,
A pair of detectors arranged symmetrically around the measuring unit 23
It reaches 21a, 21b, and the intensity of the reflected light is measured by this. Although two detectors are provided in this embodiment, the number of detectors is not limited to two, and even one detector or three detectors is provided.
It may be more than one.

Here, the configuration of the narrow band pass filter 19 provided between the light source 17 and the reflecting mirror 18 and becoming near infrared monochromatic light of a specific wavelength by passing the light emitted from the light source 17 and a request for this The physical characteristics and the like that are performed will be described. The narrow band pass filter 19 includes an arbitrary plurality of filters each having a different main wavelength pass characteristic, for example, six filters 19a to 1a.
9f, which are attached to a rotating disk and rotated by an appropriate angle so that desired filters 19a to 19f can be sequentially selected and exchanged so that the desired filters 19a to 19f are located on the line connecting the light source 17 and the reflecting mirror 18. And The main wavelength in the pass characteristics of the filter is the maximum transmission wavelength of the near infrared light that is transmitted when the incident optical axis is perpendicular to the surface of the filter. As another specific configuration example of the narrow band pass filter 19, the light source 17 and the reflecting mirror 18 are located inside,
There is also a configuration in which the plurality of filters 19a to 19f are formed in a prismatic shape and can be rotated about the center point P by means of a motor 25 or the like (see FIG. 3). If the inclination angle of the rotation surface of the narrow band pass filter 19 with respect to the incident optical axis can be finely and continuously adjusted by a means such as an electric motor, it shifts from the main wavelength of the pass characteristic of each filter. It is possible to continuously generate near infrared monochromatic light having different wavelengths.

Next, the physical characteristics required for the narrow band pass filter 19 will be described with reference to FIG. FIG. 4 is a graph (absorbance curve) showing the relationship between the irradiation wavelength and the absorbance when different sample rices are irradiated with near-infrared light whose wavelength continuously changes. The absorbance log Io / I is the common logarithm of the reciprocal of the ratio of the reflected light amount I from the sample rice to the reference irradiated light amount (total irradiated light amount) Io. The curve A shown by a solid line is Nipponbare with an amylose content of 21.4% in Table 1 above, the curve B shown by a dashed-dotted line is Koshihikari with a content of 19.9%, and the curve C shown with a dotted line is Ishikari with a content of 23.2%. Each case is shown. From the figure, the short-wavelength region of near-infrared light of 1900 nm or less is a low absorbance region, and there is a slight difference in the absorbance difference with respect to the content of each component constituting rice such as amylose, protein, and water. It can be easily understood that a high absorbance region is reached with a wavelength of 1900 nm as a boundary, and that some of the contents of the above respective components remarkably appear as a difference in absorbance. Since the present invention elucidates this phenomenon and uses it to measure the content of a predetermined component contained in rice, the wavelength of near-infrared monochromatic light irradiated on rice for measurement is , Wavelength range 1900-25
Of 00 nm, a specific peak is seen on the absorbance curve for each component, for example 1960 nm, 2030 nm, 2100 nm, 2130 nm, 22
Wavelengths such as 70 nm and 2370 nm are suitable. Therefore, each of the filters 19a to 19f included in the narrow band pass filter 19 has a specific wavelength pass characteristic of each wavelength in order to produce near-infrared monochromatic light of each wavelength suitable for measuring each component of rice. That is, it is required to have a dominant wavelength.

Next, referring to FIG. 3 and FIG. 5 to FIG.
Details of the sample supply device including the sample crushing device 12 and the sample rice transport device 14 will be described.

First, the configuration of the rice polishing apparatus 11 will be described. Supply hopper 10
The lower opening 26 is provided with a shutter 27 that is operated manually or by an electromagnetic solenoid (not shown). The upper end of the funnel base 28 is connected to the lower opening 26, and the lower end of the funnel base 28 is connected to the supply unit 29 of the rice polishing apparatus 11. A screw roll 31 axially attached to the rotating shaft 30 is provided below the supply unit 29, and a stirring roll 32 is axially attached to the rotating shaft 30 continuously to the screw roll 31. And, the rice bran polishing white tube 33 of the porous wall that encloses the screw roll 31 and the stirring roll 32 is formed in a cylinder or a polygonal tube and is laid sideways, whereby the gap between the rice bran polishing white cylinder 33 and the stirring roll 32 is provided. A whitening chamber 34 whose main part is is formed. The area around the bran removal white tube 33 forms a bran chamber 35, and the lower part of the bran chamber 35 is formed into a bran hopper 36, the lower end of the bran hopper is connected to the bran duck 37, and the end of the bran duct 37 is It is connected to a cyclone collector (not shown). Sign
Reference numeral 84 is an electric motor that rotates the rotating shaft 30.

A resistance plate 39 is provided at a discharge port 38 at the opposite end of the supply unit 29 so that the resistance plate 39 can move far and away with respect to the discharge port. That is, the lever 40 whose one end is connected to the resistance plate 39 is screwed at the other end to the screw shaft 42 which is directly connected to the shaft of the forward / reverse rotation motor 41, and the forward / reverse rotation motor 41 is connected.
The rotation of the lever causes the lever 40 to rotate around the fulcrum portion, thereby moving the resistance plate 39 into and out of the discharge port 38. A rice grain whiteness detector 43 is attached to the resistance plate 39, and this polishes the sample rice to a constant whiteness. The term "whiteness" as used herein refers to whiteness, whiteness increase (degree of whiteness with respect to brown rice), yield, and the like. In this embodiment, whiteness will be described. That is, whiteness means 0 degree when 100% of the irradiation light is absorbed and 100 degrees when 100% of the reflected light is reflected. Explaining in detail based on FIG. 5, a part of the resistance plate 39 is opened, and a transparent plate 45 is embedded in the opening 44 to face the transparent plate 45.
46 and a light receiving element 47 are provided. The light emitter 46, the light receiving element 47, and the forward / reverse rotation electric motor 41 are connected via the control device 4, and the reference whiteness suitable for the absorbance measurement is preset in the storage device 4b of the control device 4. The rice grain whiteness detector 43 was attached to the resistance plate 39 in the present embodiment,
Other parts may be used as long as they are near the discharge port 38.

Referring back to FIG. 3, a discharge gutter 48 leading to the outside of the machine is connected to the discharge port 38, and a communication gutter 49 that branches off from the discharge gutter 48 and faces the supply part of the crusher 12 is formed. Gutter
A switching valve 50 operated by an electromagnetic solenoid or the like (not shown) is provided at a branch portion between the connection gutter 48 and the connection gutter 49. The switching valve 50 normally closes the communication gutter 49 side, and operates the solenoid to operate the communication gutter 49 only when the rice grain whiteness detector 43 detects the reference whiteness set in the control unit 4. It is formed so as to communicate with each other.

Next, the sample crushing device 12 will be described in detail with reference to FIGS. 3 and 6. A rotating shaft 54 is rotatably hung over a casing 53 having an upper part with a supply part 51 and a lower part with a discharge part 52. The rotating shaft 54 has a crushing blade 55 and a stirring blade 56 each having a blade portion at its tip. It has been planted. In addition, the supply unit 51 and the discharge unit
52 is provided with a supply part opening / closing lid 57 and a discharging part opening / closing lid 58, and the opening / closing lids 57, 58 are respectively provided with opening / closing lids 57, 58.
There are provided tension coil springs 59, 60 for urging the coil in the closing direction, and electromagnetic solenoids 61, 62 for opening the respective opening / closing lids 57, 58 against the tension coil springs 59, 60. Reference numeral 63 is a variable speed electric motor directly connected to the rotary shaft 54, and the variable speed electric motor 63 is installed on a load cell balance 64, by which the total weight of the crushing device is measured. Then, the rice grain whiteness detector 43 detects the reference whiteness and the switching valve 50 operates, and at the same time, the electromagnetic solenoid.
When the supply opening / closing lid 57 is opened by exciting 61 and a constant weight of sample rice is put into the casing 53, the switching valve 50 is switched and the supply opening / closing lid 57 is closed, and the variable speed electric motor 63 is rotated at high speed. Then, the sample rice in the casing 53 is finely crushed, and then the discharge solenoid opening / closing lid 58 is opened by the electromagnetic solenoid 62 to discharge the sample rice into the hopper 65. A drive circuit (not shown) which is stored in 4b (ROM) and operates the electromagnetic solenoids and the electric motor is connected to the control device 4. In addition, when measuring without crushing the sample rice, the variable speed electric motor 63 rotates at low speed by turning on the "no crush" button of the operation push button 7, so the sample rice can be different types of rice grains. Even if it exists, it is sufficiently stirred.

Next, referring also to FIG. 7, sample rice finely crushed by the crushing device 12 (may be just stirring without crushing) is filled in a sample container 13 in a state capable of measuring absorbance. Then, the sample rice transporting device 14 for moving the sample container 13 to a position directly below the measuring unit 23 of the near infrared spectroscopy analyzer 3 will be described.

The sample container 13 is attachable / detachable to / from a guide groove 68 provided in a container holder 67 fixed to a sample container moving guide 66. A support shaft 69 having a round cross section is inserted into the hollow shaft of the sample container moving guide 66, one side of the support shaft 69 is attached to a turning handle 70, and the other side is supported by a bearing stand 71. A rack 72 is fixedly installed in the length direction of the outer circumference of the sample container movement guide 66.
The pinion gear 75 of the electric motor 74 mounted on the motor base 73 loosely fitted in 66 meshes. Motor stand 73 is a telescopic rod
It is connected to a fulcrum base 78 by an electromagnet 77 equipped with 76. The fulcrum base 78 is fixed to a receiving base 79 (see FIG. 3) fixedly installed on the bottom wall of the cabinet 2. In FIG. 3, reference numeral 80 is a rotary roller for compressing and filling the crushed sample (or non-crushed sample) in the sample container 13 and removing an excessive amount of the sample to make the surface flat, and reference numeral 81 indicates the end of measurement. A jet nozzle for removing the sample from the inside of the sample container 13 with a blast and for cleaning, and a reference numeral 82 is a cleaner for contacting and cleaning the transparent glass plate 83 when the sample container 13 is moved. The transparent glass plate 83 is stretched over the measuring unit 23 so that crushed sample rice or the like does not enter the inside of the integrating sphere 20.

Next, a specific operation in the above embodiment will be described. First, the light source 17 is turned on by operating the operation push button 7, and the near-infrared spectroscopic analyzer is operated until near-infrared monochromatic light of a specific wavelength reaching the measuring unit 23 based on the light emitted from the light source 17 is stabilized. Preheat the whole of 3.

While preheating the near-infrared spectroscopic analysis device 3, sample rice (brown rice or white rice) is put into the supply hopper 10, the electric motor 74 is rotated by operating the operation push button 7, and the sample container 13 is moved to the sample crushing device 12. It is moved to a predetermined position directly below the hopper 65 provided below the. When the movement of the sample container 13 to the predetermined position is completed and the operation of the electric motor 74 is stopped, the shutter 27
Is opened manually or by an electromagnetic solenoid (not shown), and the sample rice in the supply hopper 10 is discharged through the lower opening 26.

When the shutter 27 is opened, the electric motor 84 is activated by an appropriate limit switch (not shown) operated by the shutter 27 and the rice polishing apparatus 11 is driven. Feeding hopper 10, lowering the opening 26 of the funnel stand 28 to feed down the feeding section 29.
The sample rice that has reached the stage is transferred to the whitening chamber 34 side by the rotating screw roll 31, and subsequently compressed by the stirring roll 32.
While being stirred and flowing to the discharge port 38 side, the surface layer portion of the rice grains is peeled off due to the friction between the grains and the friction between the grains and the bran removal and polishing unit 33, and the rice is polished. The peeled rice grain surface layer portion leaks into the bran collecting chamber 35 from the porous wall of the bran removing and polishing white cylinder 33, and is discharged to the outside of the machine through the bran collecting hopper 36. At this time, the resistance plate 39 keeps the pressure in the whitening chamber 34 at a moderately high pressure and the rice polishing proceeds efficiently.
The rice grain whiteness detector 43 that monitors the whiteness of the sample rice discharged from the discharge port 38 is attached to the 39, and by this,
When the sample rice is other than the standard milling degree preset in the storage device 4b of the controller 4, the sample rice is discharged from the discharge gutter 48 to the outside of the cabinet 2. That is, the rice grain whiteness detector 43
The light from the light-emitting body 46 in FIG. 2 is radiated to the sample rice through the transparent plate 45, the reflected light from the sample rice is received by the light receiving element 47, and the amount of the received light is converted into an electric signal, and the control device 4 performs the reference whitening. Compared to the degree. The amount of received light from the sample rice taken into the control device 4 is smoothed and compared with the reference whiteness. Then, when the detection value of the rice grain whiteness detector 43 is smaller than the reference whiteness, the forward / reverse rotation electric motor 41 is rotated in a predetermined direction via a drive circuit (not shown) by a command from the control device 4, The lever 40 is rotated to gradually bring the resistance plate 39 closer to the discharge port 38 side. When the resistance plate 39 moves in the direction of closing the discharge port 38, the internal resistance of the whitening chamber 34 rises, the surface layer portion to be peeled off becomes deeper, and the whitening degree becomes higher.

In this way, when the milling degree gradually increases and reaches the reference milling degree, the forward / reverse rotation electric motor 41 is stopped and the switching valve 50 is switched by an electromagnetic solenoid or the like (not shown) to communicate the milled rice discharged from the discharge port 38. Lead to the gutter 49 side. Simultaneously with the switching of the switching valve 50, the electromagnetic solenoid 61 is excited to open the supply part opening / closing lid 57, whereby the polished rice (sample rice) flowing down the continuous gutter 49 is put into the casing 53. casing
When the sample rice is accumulated in 53 to some extent and the load cell balance 64 senses a predetermined weight, the switching valve 50 operates to close the communication gutter 49, and the electromagnetic solenoid 61 demagnetizes to close the supply opening / closing lid 57. To achieve. The variable-speed electric motor 63 rotates at high speed as the supply unit opening / closing lid 57 closes, and the sample rice in the casing 53 is finely crushed by the crushing blades 55. When the particles of the sample rice are crushed to about 50 microns required for measuring the absorbance, the variable speed electric motor 63 is stopped by the timer (not shown), and at the same time, the electromagnetic solenoid 62 is used to open and close the discharge opening / closing lid.
58 opens to discharge powdered sample rice into hopper 65.
At this time, the sample rice spilling out of the hopper 65 and the contact gutter 49
The sample rice spilled when the rice grains are put into the casing 53 from the inside falls into the receiving box 15 installed below. In the present embodiment, the case of crushing the sample rice has been described, but in the case of no crushing, the variable speed electric motor 63 is rotated at a low speed,
The sample rice is stirred by the stirring blade 56 and then discharged into the hopper 65. As a result, when a plurality of rices are mixed and simultaneously measured, the sample rice is sufficiently agitated and the measurement error is reduced.

The fine-powdered sample rice thus produced is received by the sample container 13 located immediately below the hopper 65, and the sample rice that exceeds the received amount and rises up on the container 13 becomes the inbox 15.
To fall. Next, by operating the push button 7 for operation or automatically restarting the electric motor 74, the sample container 13 containing the sample rice is placed in the measuring unit 23 of the near infrared spectroscopy analyzer 3.
The operation moves to a predetermined position directly below. In this conveyance process, the sample rice in the state of being swelled in the sample container 1 is packed in a compressed state by the rotating roller 80, and the excessive amount of sample is removed by the receiving box 15 so that the surface of the sample rice is shaped into a flat surface. . When the sample container 13 is placed at a predetermined position,
The electric motor 74 automatically stops its operation. In this way, the preparation for measurement is completed. In this embodiment, the supply hopper 10
The case where the sample rice introduced from the above is filled in the sample container 13 and the sample rice transport device 14 for transporting the sample rice to the measuring unit 23 is further provided has been described, but in the external supply unit 16 immediately below the measuring unit 23. A sample container mounting box 5 is detachably mounted, the mounting box is pulled out from the cabinet 2, a sample container filled with a crushed sample is placed, and then the sample container mounting box 5 is inserted into the cabinet 2 Of course, it can be configured to supply rice.

After the measurement preparation work is completed, first, the filter 19a having the main wavelength of 1960 nm is selected so as to be on the line connecting the light source 17 and the reflecting mirror 18 (see FIG. 2), and the wavelength 19
Measurement work of reflection absorbance when the sample rice 24 is irradiated with 60 nm near-infrared monochromatic light is started. The measurement work of the reflection absorbance is performed by measuring the total irradiation light amount irradiated to the sample rice 24, that is, the reference irradiation light amount, and actually reflected by the sample rice 24 when the sample rice 24 is irradiated with the reference irradiation light amount. Measurement of the amount of reflected light. Either of these two measurements may be performed first for one filter, but the description will be made assuming that the measurement of the reference irradiation light amount is performed first. The measurement of the reference irradiation light amount is performed by rotating the tilt angle of the reflecting mirror 18 whose tilt angle is variable to such an angle that these reflected lights directly hit the inner wall of the integrating sphere 20 by using a motor or the like ( (Not shown) is performed in a changed state. By doing so, the light from the reflecting mirror 18 directly applied to the inner wall of the integrating sphere 20 finally reaches the detectors 21a and 21b while diffusely reflecting the inner wall in multiple directions, and is detected as the reference irradiation light amount. To be done. On the other hand, the amount of reflected light from the sample rice 24 is measured by the above-described principle after the tilt angle of the reflecting mirror 18 is returned to the original position shown in FIG. It should be noted that the control device 4 executes the first selection of filters after the preparation for measurement, the measurement of the reference irradiation light amount, and the measurement of the reflected light amount.
It goes without saying that the procedure program can be stored in the ROM in the storage device 4b and automatically executed according to the program. In addition, it is also useful to improve the measurement accuracy that the reference irradiation light amount and the reflected light amount of one filter are measured a plurality of times so that the average thereof can be taken as the measurement value. Detector 21a, 21b
The measured values based on the reference irradiation light amount and the reflected light amount from the sample rice 24 detected by the control device 4 are measured data for calculating the contents of rice constituents such as protein, amylose, and water. They are contacted and once stored in a writable memory (hereinafter referred to as RAM) in the storage device 4b.

When the measurement of the absorbance at the irradiation wavelength of 1960 nm is completed, the process shifts to the measurement of the absorbance at the next irradiation wavelength, that is, 2030 nm in this example. Here, too, the measurement of the reference irradiation light quantity is as described above.
It is carried out in the same manner and procedure as at 1960 nm. As in the previous time, each measured value is communicated to the control device 4 as actual measurement data for calculating the content rate of each component, and stored in the storage device 4b.
Temporarily stored in RAM. Similarly in the following, each absorbance measurement at each remaining irradiation wavelength, that is, wavelength 2100nm, 2130nm, 2270nm, 2
The absorbance measurement at 370 nm is sequentially performed, and each measurement value is communicated to the control device 4 as actual measurement data and stored in the RAM.

It should be noted that the replacement / selection operation of each filter 19a to 19f of the narrow band pass filter 19 accompanying the transition to the absorbance measurement at the next specific wavelength after the measurement of the absorbance at a certain specific wavelength is normally performed by the memory of the control device 4. Although it is automatically performed according to the procedure program written in advance in the ROM in the device 4b, even in the case of the present embodiment, it is not always necessary to perform the absorbance measurement for all the above 6 wavelengths, and it is the object of measurement. The wavelength can be arbitrarily selected in consideration of the accuracy required for the taste evaluation value to be obtained or the time required for the measurement, and the selection can be made by the measurement wavelength selection button in the operation push button 7. it can.

The above-described measurement of the absorbance is performed by simply replacing the six filters 19a to 19f set in the narrow band pass filter 19 in order to measure the spot-like absorbance at each main wavelength of each filter 19a to 19f. Although it was a method, 90 ° which is the standard of the incident angle of the incident light on the surface of the filter
, The maximum transmission wavelength shifts from the main wavelength in the range of several tens of nm, and the continuous absorbance in the wavelength region 1900 to 2500 nm in which the difference in the component content significantly appears in the absorbance difference is utilized. Measurement is also possible. In the case of the first embodiment (see FIG. 2), the angle of the incident optical axis to the narrow band pass filter 19 formed in a disc shape is adjusted based on a command signal from the control device 4 by an appropriate adjusting means such as an electric motor ( This is possible by a gradual and continuous variation (not shown).

Next, the arithmetic unit 4c of the control device 4 uses a large amount of actual measurement data obtained by the absorbance measurement stored in the RAM of the storage device 4b, that is, the measured values of the reference irradiation light amount and the reflected light amount at each measurement wavelength, and the storage device. Calculate the contents of amylose, protein, and water, which are important components for evaluating the taste of rice, based on the component conversion factors for calculating the contents of each component stored in ROM of 4b in advance. . Note that this component conversion coefficient, which is written in advance in the ROM of the storage device 4b for each component, is a detector based on the content rate of each component measured using, for example, a chemical quantitative analysis method for many sample rices. It is a constant obtained by multiple regression analysis after signal processing of the absorbance measurement value from. Next, the arithmetic unit 4c first calculates the taste-related value K by the calculation formula (1) shown below based on the respective contents of amylose, protein and water obtained as described above.

K = (amylose content) ^A x (protein content) ^B x {15
+ | 15- (water content) |} ^C (1) In the above calculation formula (1), A, B and C are ROMs of the storage device 4b.
In the case of evaluating the taste of Japanese rice, which is a specific coefficient that is stored in advance in, or is input to the control device 4 via the input device 9 when measuring the sample, which is a specific coefficient for calculating the comprehensive evaluation value of the taste. , A = 1.0, B = 0.3, C = 0.75 are suitable, but these specific coefficients may have different standard tastes depending on the region or country in which the rice is eaten, so different numerical values may be used. In some cases, it may be more suitable.

The arithmetic unit 4c further calculates a comprehensive evaluation value T of the taste of rice based on the taste-related value K obtained by the above expression (1) by the following calculation expression (2). The larger the taste evaluation value T, the better the taste.

T = 50000 / K ² (2) Comprehensive evaluation value T of the taste calculated according to the above formulas (1) and (2), and amylose obtained in the process of obtaining the evaluation value T, The contents of each component such as protein and water are displayed on the display device 6 at the same time when the calculation by the arithmetic device 4c is completed.
In addition to being visually displayed, a hard copy of each calculated value is automatically sent from the printer 8 automatically or based on a command to the operation push button 7. Regarding the content of amylose, since the content ratio with amylopectin that constitutes starch together is more important than the content ratio of amylose itself, it is preferable to display the content ratio rather than the content ratio. .

When all the absorbance measurement of the sample rice is completed, the electric motor 74 is activated to move the sample container 13 to a predetermined position below the hopper 65 for discharging the sample rice after the measurement. At that time, the cleaning device 82 comes into contact with the transparent glass plate 83 and slides on the surface to remove the deposit. Next, by operating the electromagnet 77, the sample container moving guide 66 is rotated by 90 °, and the sample rice in the sample container 13 is discharged toward the receiving box 15 located below. At the same time, the jet nozzle 81 is operated, and the high-pressure air discharged from the jet nozzle 81 cleans the inside of the sample container 13 in preparation for the next measurement. In addition, a spray nozzle may be provided in the rice polishing device 11 and the crushing device 12 as needed. Although the case where the sample container 13 automatically reciprocates by the operation of the electric motor 74 has been described, the movement is performed by the turning handle.
Manual operation by pushing and pulling 70 can also be performed, and the sample rice can be discharged from the sample container 13 by appropriately rotating the rotating handle 70. Further, in order to dispose the sample prepared externally alone in the measuring section 23 of the near-infrared spectroscopic analysis device 3 without using the sample supply device, the rotation handle 70 is pushed to temporarily move the sample container 13 to the measuring section 23. After moving to the lower part, the sample container 13 is pulled out from the external supply section 16, sample rice is filled in the sample container 13 and then inserted into the indoor groove 68 of the container holder 70.

In the above-mentioned taste evaluation device, the reflection-type near-infrared spectroscopic analysis is carried out by measuring the intensity of light when the sample rice is irradiated with near-infrared monochromatic light of a specific wavelength, by measuring the intensity of the reflected light from the sample rice. Although the device was used, as shown in FIG.
The bottom of 13 is formed of a transparent glass plate 13a, and a detector 21c is arranged below the measurement unit 23 to measure the intensity of transmitted light that has passed through the sample rice, and the transmission type near infrared spectroscopy is performed. An analyzer can also be used. Furthermore, when the absorbance is measured based on both the reflected light and the transmitted light, a more precise near infrared spectroscopic analyzer can be provided.

In the above description, among amylose and amylopectin that compose starch, it was stated that the texture evaluation value of rice is obtained based on the analysis of amylose, but the content rate of amylopectin instead of amylose was measured, and the specific coefficient of amylopectin was determined. Similar results can be obtained by setting the expression (1).

In addition to the above-described major components of starch (amylose or amylopectin), protein, and water, the content of other components such as fat is measured, and the specific coefficient for fat is set in the formula (1). By doing so, it is possible to obtain a more accurate comprehensive evaluation value of taste.

〔The invention's effect〕

As described in detail above, according to the rice taste evaluation method and apparatus for rice according to the present invention, a sensory test based on taste with individual differences, or a time-consuming, skill-based chemical quantitative analysis or the like method is not required, Anyone can easily obtain an accurate comprehensive evaluation value of rice taste in a short time. In particular, the content rate of rice components is as follows: surface layer (bran layer) and endosperm (endosperm)
Since there is a big difference between and, it is possible to secure a high degree of accuracy in the taste evaluation values when comparing the comprehensive evaluation values of the taste of various rice by measuring with a constant milling degree of the sample rice. it can.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of an apparatus and a working method used in the present invention, FIG. 2 is a schematic sectional view of an essential part of the near-infrared spectroscopic analyzer of FIG. 1, and FIG. 3 is an essential part thereof. Sectional drawing, FIG. 4 is a graph (absorbance curve) showing the relationship between near infrared irradiation wavelength and absorbance for rice of different brands, FIG. 5 is a partially enlarged sectional view of the rice polishing apparatus of FIG. 1, 6 FIG. 7 is a side view of the crushing device, and FIG. 7 is a perspective view of a main part of the sample transporting device. In the figure, 1 ... rice taste evaluation device, 2 ... cabinet,
3 ... near infrared spectroscopy analyzer, 4 ... control device, 4a ... input / output signal processing device, 4b ... storage device (ROM, RAM), 4c ...
… Computing device, 5 …… Sample container mounting box, 6 …… Display device,
7 ... Operation push buttons, 8 ... Printer, 9 ...
… Input device, 10 …… Supply hopper, 11 …… Rice milling device, 12
…… Sample crushing device, 13 …… Sample container, 14 …… Sample rice transporting device, 15 …… box, 16 …… external supply part, 17 …… light source, 18
...... Reflector, 19 ...... Narrow band pass filter, 20 ...... Integrating sphere, 21a, 21b, 21c ...... Detector, 22 …… Lighting window, 23 …… Measuring part, 24 …… Sample rice, 25 …… Electric motor, 26 ... Lower opening, 27 ... Shutter, 28 ... Funnel stand, 29 ... Supply section, 30
...... Rotary shaft, 31 …… Screw roll, 32 …… Stirring roll, 33
…… Bran removal machine, 34 …… Whitening room, 35 …… Bran collection room, 36 ……
Collecting bran hopper, 37 …… Bran duct, 38 Discharge port, 39 …… Resistance plate, 40 …… Lever, 41 …… Forward / reverse rotation motor, 42 …… Screw shaft, 43 …… Rice grain whiteness detector, 44… … Aperture, 45 …… Transparent plate, 46 …… Light emitter, 47 …… Light receiving element, 48 …… Discharge gutter, 49
...... Communication gutter, 50 ...... Switching valve, 51 …… Supply part, 52 …… Discharge part, 53 …… Casing, 54 …… Rotary shaft, 55 ・ ・ ・ Crushing blade, 56
...... Stirring blade, 57 …… Supply part opening / closing lid, 58 …… Discharging part opening / closing lid, 59,60 …… Tension coil spring, 61,62 …… Electromagnetic solenoid, 63 …… Variable speed electric motor, 64 …… Load cell balance , 65 ...
… Hopper, 66 …… Sample container moving guide, 67 …… Container holder, 68 …… Guide groove, 69 …… Support shaft, 70 …… Rotating handle, 71 …… Bearing stand, 72 …… Rack, 73 …… Motor stand, 74 …… electric motor, 75 …… pinion gear, 76 …… telescopic rod, 77 …… electromagnet, 78 …… fulcrum stand, 79 …… cradle, 80…
… Rotating roller, 81 …… Injection nozzle, 82 …… Cleaning device, 83
...... Transparent glass plate, 84 …… electric motor.

Claims (10)

[Claims] 1. A component conversion coefficient is determined from the relationship between the content of a plurality of predetermined components that affect the taste of rice and the absorbance of the rice when it is irradiated with near infrared light. The specific coefficient is determined from the relationship between the content rate of rice and the comprehensive evaluation value of rice taste obtained by sensory, and the absorbance is measured by irradiating it with near-infrared light without heat or chemical treatment of the sample rice. Then, the content rate of the plurality of predetermined components in the sample rice is obtained from the absorbance and the component conversion coefficient,
Then, in the taste evaluation method of rice, which obtains a comprehensive evaluation value of the taste of the sample rice from this content rate and the specific coefficient, after the sample rice is whitened to have a substantially constant degree of whiteness, A method for evaluating the taste of rice, which comprises measuring the absorbance of infrared light. 2. The taste evaluation of rice according to claim (1), wherein the predetermined component affecting the taste of rice is amylose or amylopectin, water, protein, fat and fatty acid. Method. 3. The taste evaluation method for rice according to claim 1, wherein the light reflected from the sample rice is received and the absorbance of near infrared light by the sample rice is measured. 4. The method according to claim 1, wherein the light transmitted through the sample rice is received to measure the absorbance of near infrared light by the sample rice.
Item or the method for evaluating the taste of rice according to item (2). 5. The claim (1) or (2), wherein the absorbance of near infrared light by the sample rice is measured by receiving the light reflected from the sample rice and the light transmitted through the sample rice. The method for evaluating the taste of rice described. 6. A device for measuring a plurality of predetermined components having an influence on the taste of rice without heat treatment or chemical treatment and comprehensively evaluating the taste of sample rice, which comprises a component analyzer and a controller. The component analyzer has a means for measuring and outputting the absorbance of near-infrared light by the sample rice, and the control device has the content ratio of the plurality of predetermined components and the absorbance when the rice is irradiated with near-infrared light. And a storage means for storing a specific coefficient determined from the relationship between the component conversion coefficient determined from the relationship with the content rate of the plurality of predetermined components in rice and the comprehensive evaluation value of the taste of rice obtained by sensory sense, and In order to polish the sample rice so that it has a nearly constant degree of whiteness, in a rice taste evaluation device having a calculating means for calculating and outputting the comprehensive evaluation value of the taste based on the absorbance of the sample rice and the component conversion coefficient and the specific coefficient. Rice polishing A device for evaluating the taste of rice, which is characterized in that 7. The rice taste evaluation device according to claim 6, wherein the component analysis device comprises a light receiver for light reflected from the sample rice. 8. The taste evaluation device for rice according to claim 6, wherein the component analysis device is provided with a light receiver for light transmitted through the sample rice. 9. The rice taste evaluation device according to claim 6, wherein the component analysis device comprises a light receiver for light reflected from the sample rice and a light receiver for light transmitted through the sample rice. . 10. A crushing device for crushing the sample rice into finely crushed grains is provided downstream of the rice polishing device.
Item 9. The taste evaluation device for rice according to any of items (9) to (9).