Shelf life evaluation device and method for evaluating shelf life

Abstract

To evaluate the shelf life of fresh produce.SOLUTION: A shelf life evaluation device 100 according to the present invention includes: light sources 113, 123 for irradiating fresh produce W with excitation light, which is ultraviolet light; cameras 112, 122 for collecting fluorescent light in the surface layer of the fresh produce W irradiated with the ultraviolet light, thereby generating a fluorescent light image of the fresh produce W; and a computer 130 for determining the shelf life of the fresh produce W on the basis of the brightness of the fresh produce W in the fluorescent light image.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an evaluation device and an evaluation method for evaluating the shelf life of fruits and vegetables. [Background technology]

[0002] Patent Document 1 describes a flaw detection device that detects flaws on the skin of fruits and vegetables. The flaw detection device includes an ultraviolet light irradiator (black light) that irradiates ultraviolet light onto the skin of fruits and vegetables, an image acquisition unit (digital camera) that acquires a fluorescent image of the fruits and vegetables by collecting the fluorescence from the surface of the fruits and vegetables, and a flaw detection unit (computer) that detects flaws on the skin of the fruits and vegetables based on the fluorescent image. The flaws detected by the flaw detection device are taken into consideration as one element for judging the external quality of the fruits and vegetables. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-188521 A Summary of the Invention [Problem to be solved by the invention]

[0004] Traditionally, fruits and vegetables have been packed and shipped in boxes according to grades determined based on their external and internal quality. However, even fruits and vegetables sorted into the same grade have different shelf lives (days after shipping), making it difficult to ship them with uniform shelf lives.

[0005] Therefore, an object of the present invention is to provide an evaluation device and an evaluation method capable of evaluating the shelf life of fruits and vegetables. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, the shelf life evaluation device of the present invention is characterized by comprising a light source that irradiates excitation light onto fresh produce, an imaging unit that generates a fluorescent image of the fresh produce by collecting fluorescence from the surface layer of the fresh produce irradiated with the excitation light, and a judgment unit that judges the shelf life of the fresh produce based on the fluorescent reaction of the fresh produce in the fluorescent image.

[0007] The determination unit determines the shelf life based on a ratio of fluorescent areas of the fruits or vegetables in the fluorescent image to different color areas having a different color from the fluorescent areas.

[0008] The determination unit determines the shelf life based on the fluorescence intensity of the fruit or vegetable in the fluorescence image.

[0009] The determination unit determines the shelf life based on a change in the fluorescent color of the fruit or vegetable in the fluorescent image.

[0010] Furthermore, the light source is configured to irradiate the excitation light onto the entire outer surface of the fruit or vegetable, and the imaging unit is positioned to collect fluorescence from the entire surface layer, thereby generating an image of the entire surface layer.

[0011] In order to achieve the above-mentioned object, the shelf life evaluation method of the present invention is characterized by including an irradiation step of irradiating excitation light onto fresh produce, an image generation step of collecting fluorescence from the surface layer of the fresh produce irradiated with the excitation light and generating a fluorescent image of the fresh produce, and a judgment step of judging the shelf life of the fresh produce based on the fluorescent reaction of the fresh produce in the fluorescent image. Effect of the Invention

[0012] According to the present invention, the shelf life of fruits and vegetables can be evaluated. [Brief description of the drawings]

[0013] [Figure 1]FIG. 1A is a front view of a first measurement unit included in an evaluation device according to an embodiment of the present invention; FIG. 1B is a side view of the first measurement unit; and FIG. 1C is a front view of a second measurement unit included in the evaluation device. [Diagram 2] (a) is a block diagram of an evaluation device according to a first embodiment; (b) is a block diagram of an evaluation device according to a first modification; [Diagram 3] (a) Photograph showing the changes over time in eggplant after harvest, (b) contrasting photograph of the fluorescence response of bell pepper DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [First embodiment]

[0015] Hereinafter, a shelf life evaluation device and a shelf life evaluation method for fruits and vegetables according to an embodiment of the present invention will be described with reference to the drawings. Note that the fruits and vegetables to be evaluated in this embodiment are typically fruits and vegetables belonging to the Solanaceae family, such as eggplant.

[0016] 1 and 2, shelf life evaluation device 100 of this embodiment is a device for evaluating shelf life of fruits and vegetables W, and includes a first measurement unit 110 and a second measurement unit 120. First measurement unit 110 has a function of capturing an image of one side of the fruits and vegetables W placed on a placement surface S, and second measurement unit 120 has a function of capturing an image of the other side of the fruits and vegetables W placed on the placement surface S. Each of first measurement unit 110 and second measurement unit 120 is provided with a cover 111, 121 for blocking out ambient light and forming a dark space, and light sources 113, 123 and cameras 112, 122 (digital cameras) are installed inside the cover.

[0017] The light sources 113, 123 irradiate the entire outer surface of the fruit or vegetable W placed on the placement surface S with excitation light. The cameras 112, 122 have image sensors and function as imaging units that image the fruit or vegetable W placed on the placement surface S. A polarizing filter is disposed in front of the light sources 113, 123, and irradiates the fruit or vegetable W with excitation light oscillating in a certain direction. In addition, a polarizing filter is disposed in front of the cameras 112, 122, and allows fluorescent light oscillating in other directions to enter the cameras 112, 122. In this way, by providing polarizing filters in front of each light source 113, 123 and each camera 112, 122, halation occurring on the surface of the fruit or vegetable W can be prevented.

[0018] Here, in this embodiment, a light source that irradiates ultraviolet light as excitation light to eggplant, which is the fruit or vegetable W to be evaluated, is used. When the eggplant is irradiated with ultraviolet light, as shown in the lower photograph of FIG. 3(a), the blue-white fluorescent reaction occurring on the surface of the eggplant becomes stronger over time (as the freshness decreases). Specifically, slight fluorescence occurs on the surface of the eggplant on the first day after harvest, and as the number of days after harvest increases, the area and intensity of the fluorescence on the surface of the eggplant increases. It is considered that the reason why the fluorescent intensity of the surface of the eggplant changes in this way is that the aglycone component, which is a metabolite that appears on the surface of the eggplant over time, reacts to ultraviolet light. Note that the excitation light is not limited to ultraviolet light, and may be near-infrared light or the like. Furthermore, the fluorescent reaction of the fruit or vegetable is not limited to the above example of eggplant. An example of the excitation light and the fluorescent reaction of the fruit or vegetable will be described in the second embodiment and modified examples below.

[0019] The two cameras 112, 122 generate fluorescence images by collecting fluorescence generated over the entire surface of the fruit or vegetable W. That is, the camera 112 of the first measurement unit 110 generates a fluorescence image of one side of the fruit or vegetable W by collecting fluorescence on one surface of the fruit or vegetable W. The camera 122 of the second measurement unit 120 generates a fluorescence image of the other side of the fruit or vegetable W by collecting fluorescence on the other surface of the fruit or vegetable W. These fluorescence images are generated so that areas with a strong fluorescent reaction are bright and areas with a weak fluorescent reaction are dark.

[0020] The placement surface S on which the first measuring unit 110 is provided is, for example, the transport surface of an upstream conveyor, and the placement surface S on which the second measuring unit 120 is provided is the transport surface of a downstream conveyor. An operating staff member is positioned between the upstream conveyor and the fruit or vegetable W transported by the upstream conveyor is turned upside down and placed on the transport surface of the downstream conveyor. As a result, one side (one side) of the fruit or vegetable W is imaged by the first measuring unit 110, and the other side (the other side) is imaged by the second measuring unit 120. Instead of the operating staff member, an inverting device that turns the fruit or vegetable W upside down may be provided. Also, a sensor that detects the presence or absence of the fruit or vegetable W may be provided in the first measuring unit 110 and the second measuring unit 120, and an image may be taken by the cameras 112 and 122 by irradiating ultraviolet light when the fruit or vegetable W is detected by the sensor.

[0021] 2, the camera 112 of the first measurement unit 110 and the camera 122 of the second measurement unit 120 are communicatively connected to a computer 130, and input fluorescent images to the computer 130. The CPU of the computer 130 evaluates the shelf life of the fruit or vegetable W based on the brightness in each of the input fluorescent images. In this way, the CPU of the computer 130 functions as an evaluation unit that evaluates the shelf life.

[0022] Specifically, the CPU of the computer 130 executes an evaluation program stored in the memory to perform an image conversion process, an intensity calculation process, and a determination process in this order.

[0023] The image conversion process is a process for converting a fluorescent image into an image suitable for the subsequent intensity calculation process, and in this embodiment, the fluorescent image acquired from each of the cameras 112, 122 is converted into an RGB image. Note that if the fluorescent image acquired from each of the cameras 112, 122 is an RGB image, the image conversion process may be omitted.

[0024] The intensity calculation process is a process for calculating the light and dark intensity (fluorescence intensity) of the fluorescent part, and includes, for example, a pixel value extraction process and a pixel value integration process. The pixel value extraction process is a process for extracting the value of a pixel with a strong fluorescent reaction (high fluorescent intensity), and in this embodiment, the B value (blue value) in the RGB value of each pixel is compared with a predetermined value, and if the B value is higher than the predetermined value, the B value is extracted. This pixel value extraction process is performed for all pixels of the RGB image. The pixel value integration process is a process for integrating the B values ​​of the extracted pixels. The integrated value calculated in the intensity calculation process is smaller for an RGB image with more parts with weak fluorescent reaction (parts with low light and dark intensity), and is larger for an RGB image with more parts with strong fluorescent reaction (parts with high light and dark intensity). In this way, the CPU of the computer 130 functions as an intensity calculation unit.

[0025] The determination process is a process for determining the shelf life of the fruits and vegetables W based on the calculated light and dark intensity, and the light and dark intensity is compared with the daily average value. The daily average value is the average value of the light and dark intensity on the day when the fruit and vegetables W can no longer be displayed as merchandise (shelf life expiration date), the average value of the light and dark intensity one day before the shelf life expiration date, the average value of the light and dark intensity two days before the shelf life expiration date, or the average value of the light and dark intensity 14 days before the shelf life expiration date. The average value is calculated by measuring the light and dark intensity of multiple fruits and vegetables samples harvested in advance on a daily basis. As a result of the comparison, the daily average value with the closest light and dark intensity is identified, and the shelf life is determined by identifying how many days before the shelf life expiration date the identified daily average value is.

[0026] The shelf life evaluation device 100 configured as described above is incorporated into a sorting device for fruits and vegetables W. That is, in the sorting device for fruits and vegetables W, a grade regarding the external quality and internal quality of the fruits and vegetables W is determined, and the shelf life of the fruits and vegetables W is evaluated by the shelf life evaluation device 100 of this embodiment. Then, the fruits and vegetables W are sorted according to the grade and shelf life.

[0027] In this way, the shelf life evaluation device 100 of this embodiment can individually evaluate the shelf life of the fruits and vegetables W. Furthermore, a sorting device incorporating the shelf life evaluation device 100 can ship the fruits and vegetables W not only in the same grade but also with the same shelf life.

[0028] [Second embodiment]

[0029] The shelf-hold evaluation device 100 according to the second embodiment is common to the first embodiment in that it includes a first measurement unit 110, a second measurement unit 120, and a computer 130. However, the evaluation target of the shelf-hold evaluation device 100 according to the second embodiment is different from that of the first embodiment in that the fluorescence reaction of the evaluation target when irradiated with ultraviolet light, which is excitation light, is in contrast to that of the fruit or vegetable W of the first embodiment. Below, the differences from the first embodiment will be mainly described, and the description of the common points will be omitted as appropriate.

[0030] The fruit or vegetable W according to this embodiment is a fruit or vegetable W belonging to the genus Capsicum of the Solanaceae family that has a cuticle layer on the outside of the epidermal cells, and is typically a green pepper or a chili pepper. When irradiated with ultraviolet light, the fruit or vegetable W emits bluish-white fluorescence from the cuticle layer, as shown in the right photograph of FIG. 3(b). On the other hand, the fruit or vegetable W does not emit the fluorescence from the portion where the cuticle layer is missing. The inventors discovered that the internal moisture of the fruit or vegetable evaporates from the portion where the epidermis (cuticle layer) of the fruit or vegetable is missing, and gained the knowledge that the evaporation of the internal moisture affects shelf life.

[0031] The CPU of the computer 130 determines shelf life based on the brightness in the fluorescent images acquired from the first measurement unit 110 and the second measurement unit 120. Specifically, the CPU of the computer 130 executes a surface area calculation process, a dark area calculation process, and a determination process in this order.

[0032] The surface area calculation process is a process for calculating the surface area (including a value that indexes the surface area) of the flesh of the fruit or vegetable W. As described above, since the first measurement unit 110 and the second measurement unit 120 are formed in a dark place, the background color of the fluorescent image is black, and the fluorescent portion of the fruit or vegetable W is blue-white, as shown in FIG. 3. Therefore, the CPU of the computer 130 detects the contour of one side of the fruit or vegetable W by extracting the blue-white portion (the flesh portion of one side) included in the fluorescent image input from the first measurement unit 110. Also, the CPU of the computer 130 detects the contour of the other side of the fruit or vegetable W by extracting the blue-white portion (the flesh portion of the other side) included in the fluorescent image input from the second measurement unit 120. Then, the CPU of the computer 130 calculates the surface area of ​​the fruit or vegetable W based on the size of each extracted contour. In this way, the CPU of the computer 130 functions as a surface area calculation unit that calculates the surface area of ​​the fruit or vegetable W.

[0033] The dark area calculation process is a process for calculating the area of ​​the parts with low fluorescence intensity (referred to as "dark areas") within the above-mentioned outline. Specifically, the CPU of the computer 130 extracts dark areas within the outline of each pulp part extracted in the above-mentioned surface area calculation process, and calculates the total area of ​​the extracted dark areas (a value that indicates the total area of ​​the dark areas).

[0034] The determination process is a process for determining the shelf life of fruits and vegetables W, and the CPU of computer 130 calculates the ratio of the total area of ​​dark areas to the surface area of ​​fruits and vegetables W (referred to as the "dark area ratio"). The shelf life is then determined based on the calculated dark area ratio. For example, fruits and vegetables W with various dark area ratios are prepared in advance, and a table is prepared in which the dark area ratio and shelf life days are associated based on the actual measurement results of the shelf life of each fruit and vegetable W. In the determination process, the shelf life is determined by referring to the table and extracting the shelf life days corresponding to the calculated dark area ratio. Alternatively, a table is prepared in which the dark area ratio and shelf life grade are associated based on the actual measurement results, and the shelf life is determined by referring to the table and extracting the grade corresponding to the calculated dark area ratio.

[0035] The evaluation device according to this embodiment is incorporated into a sorting device for fruits and vegetables W, similar to the evaluation device 100 of the first embodiment. The sorting device determines the grades of the external and internal quality of the fruits and vegetables W, and the evaluation device 100 of this embodiment evaluates the shelf life of the fruits and vegetables W. The fruits and vegetables W are then sorted according to the grades and shelf life of the fruits and vegetables W.

[0036] In this way, the shelf life evaluation device 100 of this embodiment can individually evaluate the shelf life of the fruits and vegetables W. Furthermore, a sorting device incorporating the shelf life evaluation device 100 can ship the fruits and vegetables W not only in the same grade but also with the same shelf life.

[0037] The shelf holding evaluation device of the present invention has been described above based on the first and second embodiments, but the present invention is not limited to the above embodiments and may be embodied in modified forms, for example, as described below.

[0038] <Variation 1> The evaluation device of the present invention is not limited to the eggplant of the first embodiment or the green pepper or chili pepper of the second embodiment, but can also evaluate the shelf life of other fruits and vegetables.

[0039] For example, shelf life may be evaluated by irradiating ultraviolet light onto broccoli. The intensity of the fluorescent reaction of broccoli gradually decreases over time. Therefore, the evaluation device of the present invention collects the fluorescent light from the surface layer of the broccoli irradiated with ultraviolet light to generate a fluorescent image, and judges shelf life based on the degree of decrease in the fluorescent intensity in the fluorescent image.

[0040] The shelf life of bananas may also be evaluated by irradiating them with ultraviolet light. The intensity of the fluorescent reaction of bananas gradually increases over time. Therefore, the evaluation device of the present invention collects the fluorescent light from the surface layer of the banana irradiated with ultraviolet light to generate a fluorescent image, and judges the shelf life based on the degree of increase in the fluorescent intensity in the fluorescent image.

[0041] The shelf life of tomatoes may also be evaluated by irradiating them with ultraviolet light, which is an excitation light. As tomatoes ripen, their fluorescent reaction changes from blue to bluish-white. The evaluation device of the present invention collects the fluorescent light from the surface layer of tomatoes irradiated with ultraviolet light to generate a fluorescent image, and judges the shelf life of the tomatoes based on the degree of change in the fluorescent color in the fluorescent image.

[0042] The shelf life of iyo mandarin oranges may also be evaluated by irradiating them with ultraviolet light, which is an excitation light. As iyo mandarin oranges ripen, their fluorescence changes to yellow. The evaluation device of the present invention collects the fluorescence from the surface layer of iyo mandarin oranges irradiated with ultraviolet light to generate a fluorescence image, and judges the shelf life of iyo mandarin oranges based on the degree of change in the fluorescence color in the fluorescence image.

[0043] As described above, the fluorescent reaction when irradiated with excitation light differs depending on the fruit or vegetable. This is thought to be due to the change in the fluorescent substance contained in the fruit or vegetable. For example, the above-mentioned broccoli contains chlorophyll, which is a fluorescent substance, and red fluorescence is generated according to the content of the chlorophyll. Since the chlorophyll content in broccoli decreases over time, the fluorescence intensity also gradually decreases accordingly. In addition, as bananas ripen, the surface color changes from green to yellow, which is due to the decomposition of the chlorophyll contained in the banana as it ripens. During the decomposition process, chlorophyll changes to a compound (fluorescent chlorophyll catabolite), which reacts with fluorescence and emits blue fluorescence. The fluorescent substances contained in fruit or vegetable are not limited to chlorophyll, and there are also fluorescent substances such as flavonoids that fluoresce green and coumarins that fluoresce blue.

[0044] <Variation 2> In the second embodiment, the shelf life is evaluated by detecting missing parts of the cuticle layer of the fruit or vegetable, but the shelf life may also be evaluated based on the color of damaged parts of the skin of the fruit or vegetable. For example, if the fruit or vegetable fluoresces red when damaged and green after recovery, the shelf life can be evaluated based on the difference in the fluorescent color. That is, when a red part is detected in the fluorescent image, it is determined to be a damaged part, and the shelf life is determined taking into account the size of the damaged part. On the other hand, when a green part is detected in the fluorescent image, it is determined that the damage has been recovered (low internal moisture evaporation), and the shelf life is determined.

[0045] <Variation 3> Although the light source in the above embodiment and modified example is configured to irradiate fruits and vegetables with ultraviolet light, it may be configured to irradiate fruits and vegetables with infrared light.

[0046] <Variation 4> As shown in FIG. 2(b), the evaluation device of the first embodiment may include a light source that irradiates visible light onto the fruit or vegetable W (hereinafter referred to as a "visible light source"). Specifically, the first measurement unit 210 and the second measurement unit 220 of the evaluation device 200 include light sources 213, 223 (hereinafter referred to as "ultraviolet light sources 213, 223") that output ultraviolet light, light sources 214, 224 (hereinafter referred to as "visible light sources 214, 224") that output visible light, and cameras 212, 222 within a cover. These two types of light sources are electrically connected to a computer 230, and are turned on in response to a turn-on signal input from the computer 230 and turned off in response to a turn-off signal input from the computer 230.

[0047] When the fruit or vegetable W to be evaluated is in the imaging position, the computer 230 inputs a turn-on signal to the visible light sources 214, 224 and a turn-off signal to the ultraviolet light sources 213, 223, and inputs an imaging command to the cameras 212, 222 as a first step. When the cameras capture images in response to the imaging command, the cameras 212, 222 collect visible light reflected on one side of the fruit or vegetable W to generate a visible light image. The generated visible light image is input from the cameras 212, 222 to the computer 230. Next, as a second step, the computer 230 inputs an turn-off signal to the visible light sources 214, 224 and a turn-on signal to the ultraviolet light sources 213, 223, and inputs an imaging command to the cameras 212, 222. When the cameras capture images in response to the imaging command, the cameras 212, 222 collect fluorescence on one side of the fruit or vegetable W to generate a fluorescence image. The generated fluorescence image is input to the computer 230.

[0048] Prior to the image conversion process, the CPU of the computer 230 calculates the surface area of ​​the fruit or vegetable W based on the input visible light image. In the determination process, the CPU of the computer 230 multiplies the calculated light and dark intensity by the reciprocal of the surface area to calculate the light and dark intensity per unit area, and determines the shelf life based on the calculated light and dark intensity. Similarly, the daily average value in this modification example 1 is calculated by multiplying the light and dark intensity of each fruit or vegetable sample by the reciprocal of its surface area to calculate the average light and dark intensity per unit area.

[0049] <Variation 5> In the above embodiment and modification 1, two measurement units (first measurement units 110, 210 and second measurement units 120, 220) are provided, but a single measurement unit capable of capturing an image of the entire surface of the fruit or vegetable W may be provided.

[0050] <Variation 6> In the above embodiment and modified example 1, the first measurement unit 110, 210 is arranged on the upstream conveyor, and the second measurement unit 120, 220 is arranged on the downstream conveyor, but this is not limited to this embodiment. For example, a single measurement unit may be provided on a conveyor that rotates and transports the fruit or vegetable W. In this embodiment, an installation area for the cover is secured so that the fruit or vegetable W can be turned over inside the cover, and a camera and an ultraviolet light source are installed so that fluorescent images of the fruit or vegetable W before and after turning over can be obtained.

[0051] <Variation 7> The cameras (imaging units) of the first measuring units 110, 210 and the second measuring units 120, 220 in the above embodiment and modification 1 may be line sensors. For example, the line sensor of the first measuring units 110, 210 is disposed above the conveyor and generates a fluorescent image by scanning the upper surface of the fruit or vegetable W moving below. The line sensor of the second measuring units 120, 220 is disposed below the joint between the upstream conveyor and the downstream conveyor and generates a fluorescent image by scanning the lower surface of the fruit or vegetable W moving along the joint.

[0052] <Variation 8> In the above embodiment, fluorescent images and visible light images of the entire fruit or vegetable W are obtained by capturing images of one side and the other side of the fruit or vegetable W, but depending on the shape of the fruit or vegetable W, a top camera that captures images of the top side of the fruit or vegetable W, a bottom camera that captures images of the bottom side of the fruit or vegetable W, a left camera that captures images of the left side of the fruit or vegetable W, a right camera that captures images of the right side of the fruit or vegetable W, a front camera that captures images of the front of the fruit or vegetable W, and a rear camera that captures images of the rear of the fruit or vegetable W may be provided, and the computer may evaluate shelf life based on the fluorescent images and visible light images captured by each camera. [Explanation of symbols]

[0053] 100 Evaluation Device 112 Camera (imaging unit) 113 Light source 122 Camera (imaging unit) 123 Light source 130 Computer (Judgment Department) 200 Evaluation Device 212 Camera (imaging unit) 213 Light source 214 Light source 222 Camera (imaging unit) 223 Light source 224 Light source 230 Computer (Judgment Department)

Claims

1. A light source that irradiates the fruits and vegetables with excitation light; an imaging unit that generates a fluorescent image of the fruit or vegetable by collecting fluorescent light from a surface layer of the fruit or vegetable irradiated with the excitation light; a determination unit for determining shelf life of the fruit or vegetable based on a fluorescent reaction of the fruit or vegetable in the fluorescent image; A shelf-hold evaluation device comprising:

2. The shelf-hold evaluation device according to claim 1 , wherein the determination unit determines the shelf-hold status based on a ratio of fluorescent areas of the fruits or vegetables in the fluorescent image to different-color areas having a different color from the fluorescent areas.

3. The shelf life evaluation device according to claim 1 , wherein the determination unit determines the shelf life based on a fluorescent intensity of the fruit or vegetable in the fluorescent image.

4. The shelf life evaluation device according to claim 1 , wherein the determination unit determines the shelf life based on a change in a fluorescent color of the fruit or vegetable in the fluorescent image.

5. The light source is provided to irradiate the entire outer surface of the fruit or vegetable with the excitation light, The shelf-hold evaluation device according to claim 1 , wherein the imaging unit is disposed so as to collect fluorescence from the entire surface layer and generate an image of the entire surface layer.

6. an irradiation step of irradiating the fruits or vegetables with excitation light; an image generating step of collecting fluorescence from a surface layer of the fruit or vegetable irradiated with the excitation light and generating a fluorescence image of the fruit or vegetable; a determining step of determining shelf life of the fruit or vegetable based on a fluorescent reaction of the fruit or vegetable in the fluorescent image; Shelf life assessment methods, including:

Images