JP5002980B2 - Rice quality measuring method and rice quality measuring device - Google Patents

Description

  The present invention relates to a rice quality measuring method and a rice quality measuring apparatus.

  Conventionally, a method of measuring food quality (freshness, taste, etc.) from food autofluorescence has been proposed (see, for example, Patent Document 1).

  This quality measurement method irradiates food with excitation light, acquires autofluorescence emitted from the food by irradiation of the excitation light, and evaluates the quality of the food using the autofluorescence intensity as an index. According to this quality measurement method, the quality of the food can be measured without subjecting the food to complicated pretreatment, so that the quality of the food can be evaluated easily and quickly.

By the way, in order to measure the quality of food with high accuracy by the quality measurement method as described above, among the plurality of components (fluorescence-derived substances) involved in the quality of food, the fluorescence intensity of the fluorescence-derived substances that particularly affect the deterioration. It is required to measure changes with high accuracy. In other words, if the food is irradiated with excitation light in a specific wavelength range corresponding to the fluorescence-derived substance, which is a quality degradation factor, and autofluorescence in a specific wavelength range that can be clearly recognized among the autofluorescence emitted by the food is not acquired, There is a problem that accurate measurement cannot be performed and measurement reproducibility cannot be obtained.
JP 2001-208745 A

  In view of the above facts, an object of the present invention is to obtain a rice quality measuring method and a rice quality measuring apparatus capable of measuring the quality of rice with high accuracy.

In order to solve the above-described problem, the rice quality measurement method according to claim 1 irradiates the rice with excitation light having a wavelength in the range of 340 nm to 380 nm, and the rice is irradiated by the excitation light. Among the autofluorescence emitted, the autofluorescence having a wavelength in the range of 420 nm to 500 nm is acquired using a fluorescence filter that blocks light having a wavelength outside the range of 420 nm to 500 nm , and the acquired autofluorescence is acquired. The quality of the rice is measured using the strength of the rice as an index.

In the method for measuring quality of rice according to claim 1, the rice is irradiated with excitation light having a wavelength in the range of 340 nm to 380 nm, that is, excitation light in a wavelength range corresponding to a fluorescence-derived substance that is a quality degradation factor of rice. The visible light with a wavelength in the range of 420 nm to 500 nm is acquired as autofluorescence, so that the self-fluorescence intensity of rice can be clearly recognized, thereby measuring the quality of rice with high accuracy can do.

  The method for measuring quality of rice according to claim 2 irradiates the rice with excitation light having a wavelength in the range of 400 nm to 440 nm, and the wavelength of the autofluorescence emitted from the rice by the irradiation of the excitation light is 440 nm. It is characterized by acquiring autofluorescence within a range of ˜540 nm and measuring the quality of the rice using the acquired intensity of autofluorescence as an index.

  In the method for measuring quality of rice according to claim 2, the rice is irradiated with excitation light having a wavelength in the range of 400 nm to 440 nm, that is, excitation light in a wavelength range corresponding to a fluorescence-derived substance that is a quality degradation factor of rice. Since the visible light having a wavelength within the range of 440 nm to 540 nm is acquired as autofluorescence among the autofluorescence emitted from the rice, it is possible to clearly recognize the autofluorescence intensity of rice and thereby measure the quality of rice with high accuracy Can do.

The rice quality measuring apparatus according to claim 3, wherein the rice is held by a holding unit, excitation light irradiation means for irradiating the rice with excitation light having a wavelength in a range of 340 nm to 380 nm, and the excitation Among the autofluorescence emitted from the rice by light irradiation, autofluorescence having a wavelength in the range of 420 nm to 500 nm is obtained using a fluorescence filter that blocks light having a wavelength outside the range of 420 nm to 500 nm. And an acquisition means.

In the rice quality measuring apparatus according to claim 3, the excitation light irradiation means emits excitation light having a wavelength in a range of 340 nm to 380 nm, that is, excitation light in a wavelength region corresponding to a fluorescence-derived substance that is a quality degradation factor of rice. Irradiating the rice, the acquisition means acquires visible light having a wavelength within the range of 420 nm to 500 nm among the autofluorescence emitted by the rice as autofluorescence, so the autofluorescence intensity of the rice acquired by the acquisition means is obtained. It can be clearly recognized, so that the quality of rice can be measured with high accuracy.

  The rice quality measuring apparatus according to claim 4, wherein the rice is held by a holding unit, excitation light irradiation means for irradiating the rice with excitation light having a wavelength in a range of 400 nm to 440 nm, and the excitation Acquisition means for acquiring autofluorescence having a wavelength in the range of 440 nm to 540 nm among the autofluorescence emitted from the rice by light irradiation.

  5. The rice quality measuring apparatus according to claim 4, wherein the excitation light irradiation means emits excitation light having a wavelength within a range of 400 nm to 440 nm, that is, excitation light in a wavelength region corresponding to a fluorescence-derived substance that is a quality degradation factor of rice. Irradiate the rice, and the acquisition means acquires visible light having a wavelength within the range of 440 nm to 540 nm as autofluorescence from the autofluorescence emitted by the rice, so the autofluorescence intensity of the rice acquired by the acquisition means is clarified. It can be recognized, and thereby the quality of rice can be measured with high accuracy.

  As described above, the rice quality measuring method and the rice quality measuring apparatus of the present invention can measure the quality of rice with high accuracy.

  FIG. 1 is a cross-sectional view showing a schematic configuration of a rice quality measuring apparatus 10 configured by applying the rice quality measuring method according to the embodiment of the present invention.

  The quality measuring device 10 has a dark box 12 formed in a box shape. Inside the dark box 12, there is provided a light source storage box 14 formed in a box shape with an open top. An excitation light source 16 constituting excitation light irradiation means is disposed inside the light source housing box 14. As the excitation light source 16, any lamp such as an ultraviolet lamp, a mercury lamp, a xenon lamp, a deuterium lamp, a halogen lamp, a tungsten lamp, a laser, a light emitting diode, and an EL can be used. It is preferable to use a light source.

  An excitation light source filter 18, which is formed in a plate shape and constitutes excitation light irradiation means and a holding portion, is detachably attached to the upper portion of the light source housing box 14. The excitation light source filter 18 is configured to block light having a wavelength other than the intended purpose. In this embodiment, the filter for blocking light having a wavelength outside the range of 340 nm to 380 nm and the wavelength of 400 nm to 440 nm are used. There are two types, one that blocks out the light that is outside.

  Further, a petri dish 20 containing a sample of rice K is placed inside the excitation light source filter 18, and the excitation light transmitted through the excitation light source filter 18 passes through the rice in the petri dish 20. K is irradiated.

  On the other hand, a CCD camera 22 constituting an acquisition unit is attached to the upper part of the dark box 12. The lens 22A of the CCD camera 22 passes through a circular hole formed in the upper part of the dark box 12, and a fluorescence filter 26 that constitutes an acquisition means together with the CCD camera 22 is detachably attached to the tip of the lens 22A. . The fluorescent filter 26 is configured to block light having a wavelength other than the intended purpose. In this embodiment, the fluorescent filter 26 blocks light having a wavelength outside the range of 420 nm to 500 nm, and the wavelength is outside the range of 440 nm to 540 nm. There are two types, one that blocks light in

  The optical axis of the lens 22 </ b> A is directed to the excitation light source filter 18, and the CCD camera 22 can image the rice K in the petri dish 20 placed on the excitation light source filter 18. A computer 30 is connected to the CCD camera 22 via a wiring 28. An image analysis program or the like is installed in the computer 30 so that an image captured by the CCD camera 22 can be displayed on the display of the computer 30 and the displayed image can be arbitrarily measured and analyzed. .

  Next, the operation of this embodiment will be described.

  In the quality measuring apparatus 10 having the above-described configuration, when the excitation light source filter 18 that blocks light outside the wavelength range of 340 nm to 380 nm is attached to the upper portion of the light source housing box 14, the lens 22 </ b> A of the CCD camera 22 is attached to the lens 22 </ b> A. A fluorescent filter 26 that blocks light outside the wavelength range of 420 nm to 500 nm is attached. On the other hand, when the excitation light source filter 18 that blocks light outside the wavelength range of 400 nm to 440 nm is attached to the upper part of the light source housing box 14, the lens 22 </ b> A of the CCD camera 22 has a wavelength other than the wavelength range of 440 nm to 540 nm. A fluorescent filter 26 for blocking the light is attached.

  Excitation light in a specific wavelength region (340 nm to 380 nm or 400 nm to 440 nm) of the excitation light irradiated by the excitation light source 16 passes through the excitation light source filter 18 and is irradiated to the rice K in the dish 20 (FIG. 1). (See arrow L1). Among the autofluorescence emitted from the rice K by this excitation light irradiation, autofluorescence in a specific wavelength region (420 nm to 500 nm or 440 nm to 500 nm) is transmitted through the fluorescence filter 26 attached to the tip of the lens 22A of the CCD camera 22. Then, the light enters the lens 22A (see arrow L2 in FIG. 1), and a fluorescent image of rice K is captured by the CCD camera 22.

  Since the captured fluorescent image of rice K is displayed on the display of the computer 30, it can be arbitrarily measured and analyzed by an image analysis program of the computer 30 or the like. In this case, there is a correlation between the fluorescence intensity (luminance) of rice K obtained from the fluorescence image and the fatty acid degree of rice K, and there is also a correlation between the fatty acid degree of rice K and the age of rice K. Since there is a relationship (that is, the fatty acid degree is used as one index for judgment of old rice), for example, the fluorescence intensity is digitized by an image analysis program or the like, and the quality of rice K ( Freshness, taste, etc.) can be measured.

  Moreover, in the quality measuring apparatus 10 according to the present embodiment, the excitation light irradiation means (the excitation light source 16 and the excitation light source filter 18) is used as a substance derived from the fluorescence of rice K, which is a factor of the rice K becoming old rice (quality degradation). The excitation light in the corresponding specific wavelength range (340 nm to 380 nm or 400 nm to 440 nm) is irradiated to the rice K, and the acquisition means (CCD camera 22 and the filter 26 for fluorescence) is an autofluorescence emitted from the rice K by the irradiation of the excitation light. Among them, since a fluorescent image of rice K is captured by visible light in a specific wavelength range (420 nm to 500 nm or 440 nm to 500 nm), the autofluorescence intensity of rice K can be clearly recognized from the captured fluorescent image, The quality of rice K can be measured with high accuracy.

  That is, in FIG. 2, the relationship between the wavelength of the autofluorescence emitted from the rice and the fluorescence intensity when the wavelength of the excitation light applied to the rice is changed is shown in a diagram. In addition, the rice sample used here has a variety of “Haenuki” and is stored at 5 ° C. as brown rice and has passed 3 months after storage.

  As shown in FIG. 2, when the sample is irradiated with excitation light having wavelengths of 340 nm, 360 nm, and 380 nm (see A, B, and C in FIG. 2), among the autofluorescence emitted from the sample, the wavelength is 420 nm to It can be seen that the fluorescence in the visible light region within the range X1 of 500 nm has a high fluorescence intensity. Therefore, as in this embodiment, the wavelength of the excitation light that the excitation light source 16 irradiates the rice K is limited to the range of 340 nm to 380 by the excitation light source filter 18 and the autofluorescence acquired by the CCD camera 22 is also reduced. If the wavelength is limited to the range of 420 nm to 500 nm by the filter 26 for fluorescence, the autofluorescence intensity emitted by the rice K can be clearly recognized.

As shown in FIG. 2, when the sample is irradiated with excitation light having wavelengths of 400 nm, 420 nm, and 440 nm (see D , E , and F in FIG. 2), among the autofluorescence emitted from the sample, the wavelength is It can be seen that the fluorescence in the visible light region within the range X2 of 440 nm to 540 nm has high fluorescence intensity. Therefore, as in this embodiment, the wavelength of the excitation light that the excitation light source 16 irradiates the rice K is limited to the range of 400 nm to 440 nm by the excitation light source filter 18, and the autofluorescence acquired by the CCD camera 22. If the wavelength is limited within the range of 440 nm to 540 nm by the filter 26 for fluorescence, the autofluorescence intensity emitted by the rice K can be clearly recognized.

  Thus, in the quality measuring apparatus 10 according to the present embodiment, the excitation light wavelength that can clearly recognize the autofluorescence intensity emitted by the rice K is found by experiment, and the wavelength region is set as the measurement wavelength. Can be measured with high accuracy. Therefore, for example, the quality of brown rice can be measured easily, quickly and with high accuracy, regardless of special experience and skill level, even at the production site and receiving site (distribution / sales site) of raw brown rice. In addition, the measurement result obtained in this way can be used as an index of rice history information (traceability) between the production site and the reception site, for example. That is, for example, the extent of the difference between the fluorescence intensity of brown rice immediately after mashing and the fluorescence intensity when it is stored as raw material brown rice in a mill after storage. Condition) can be estimated.

  In the quality measuring apparatus 10 according to the above-described embodiment, the excitation light source 16 is arranged below the sample rice K. However, the present invention is not limited to this, and the excitation light source 16 is arranged above the rice K. It is good also as a structure. In this case, however, the excitation light source filter 18 is interposed between the excitation light source 16 and the rice K.

  In the quality measuring apparatus 10 according to the above embodiment, the acquisition unit is configured by the CCD camera 22, but the acquisition unit is not limited to this, and any unit that can detect light may be used, for example, a photodiode or a photoelectron. A photo detector such as a multiplier tube may be applied. Further, the CCD camera 22 and the photodetector may be omitted, and the fluorescence transmitted through the fluorescence filter 26 may be confirmed visually.

It is sectional drawing which shows schematic structure of the quality measuring apparatus which concerns on embodiment of this invention. It is a diagram which shows the relationship between the wavelength of the autofluorescence which a rice emits, and fluorescence intensity when the wavelength of the excitation light irradiated to rice is changed.

Explanation of symbols

10 Quality measuring device 16 Excitation light source (excitation light irradiation means)
18 Filter for excitation light source (excitation light irradiation means)
22 CCD camera (acquisition means)
26 Filter for fluorescence (Acquisition means)

Claims (4)

Irradiating excitation light having a wavelength in the range of 340 nm to 380 nm toward the rice, among the autofluorescence emitted from the rice by irradiation of the excitation light, the autofluorescence having a wavelength in the range of 420 nm to 500 nm , A method for measuring rice quality, which is obtained using a fluorescence filter that blocks light having a wavelength outside the range of 420 nm to 500 nm, and measures the quality of the rice using the obtained intensity of autofluorescence as an index.   While irradiating the rice with excitation light having a wavelength in the range of 400 nm to 440 nm, and acquiring autofluorescence having a wavelength in the range of 440 nm to 540 nm among the autofluorescence emitted by the rice by irradiation of the excitation light The rice quality measurement method for measuring the quality of the rice using the acquired autofluorescence intensity as an index. A holding unit for holding rice;
Excitation light irradiation means for irradiating the rice with excitation light having a wavelength in the range of 340 nm to 380 nm;
Among the autofluorescence emitted from the rice by the excitation light irradiation, autofluorescence having a wavelength in the range of 420 nm to 500 nm is used, and a fluorescence filter that blocks light having a wavelength outside the range of 420 nm to 500 nm is used. Acquisition means for acquiring;
Rice quality measuring device. A holding unit for holding rice;
Excitation light irradiation means for irradiating the rice with excitation light having a wavelength in the range of 400 nm to 440 nm;
An acquisition means for acquiring autofluorescence having a wavelength within a range of 440 nm to 540 nm among autofluorescence emitted from the rice by irradiation of the excitation light;
Rice quality measuring device.

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