RU2666747C1 - Device for storage of fresh products and method of storage - Google Patents

Abstract

FIELD: package and storage.SUBSTANCE: storage appliance of fresh food contains a fresh food storage facility capable of storing a fresh product at a temperature not lower than temperature of cooled state; temperature tuning element capable of adjusting internal storage temperature of fresh food storage facility to a temperature not lower than temperature of cooled state; air flow generation element made to generate airflow within the storage facility fresh food; radiation element made to generate ozone or a radical by radiating of airflow with ultra-violet rays; and control element of interrupted irradiation capable to control radiation element for irradiating of airflow with ultraviolet rays in interrupted mode. Fresh product is stored in storage facility at a temperature not lower than the temperature of cooled state; airflow is formed around the fresh product; irradiate airflow with ultraviolet rays in interrupted mode and disseminate ozone or a radical throughout the region inside the storage facility by airflow.EFFECT: fresh products are stored fresh for a long period of time without oxidative damage by ozone or radical.11 cl, 15 dwg

Description

FIELD OF TECHNOLOGY

[0001] The present invention relates to a fresh food storage device and a storage method for sterilizing fresh food using vacuum ultraviolet rays during storage, cooling or thawing of fresh food.

BACKGROUND

[0002] Conventional methods for preventing the growth of fungi and bacteria on fresh foods include providing an ultraviolet lamp inside a refrigerator for emitting ultraviolet rays and sterilizing air, providing an ultraviolet lamp in a water tank or humidifier ducts for emitting ultraviolet rays and sterilizing water for humidification and etc.

In addition, sterilization is performed by generating ozone by a plasma ozone generator and spraying ozonated water inside the refrigerator, or by spraying hypochlorous acid inside the refrigerator.

[0003] Patent Document 1 discloses a storage and sterilization device in which stored food products are exposed to air that contains moisture and an oxygen radical ion generated by irradiating a photovoltaic cell with ultraviolet rays.

Patent Document 2 discloses a humidifier in which an ultraviolet lamp is used to irradiate water for humidification with ultraviolet rays, or ozone is generated by irradiating the introduced air with ultraviolet rays and is emitted from the air outlet.

Patent Document 3 discloses sterilization of food products with an ultraviolet lamp inside the store, food storage and circulation of chilled air inside the store.

LIST OF REFERENCE MATERIALS

PATENT LITERATURE

[0004]

Patent Document 1: JP2010-193829A

Patent Document 2: JP2013-155995A

Patent Document 3: JP2014-25613A

SUMMARY OF THE INVENTION

TASKS TO BE SOLVED

[0005] In a method for sterilizing stored food products with ozone or a radical generated by emitting ultraviolet rays, the oxidative effect of ozone or radical can cause oxidative damage to the stored food.

For example, Patent Document 1 discloses the use of an ultraviolet lamp in which ultraviolet rays having a wavelength of 240 nm or less are cut out to prevent ozone from oxidizing stored foods (paragraph 0042). However, in this method, the ozone generation efficiency is reduced, and the amount of ozone generated cannot be precisely controlled.

None of Patent Documents 2 or 3 discloses a solution to the above problem.

In addition, an ultraviolet lamp equipped with a mercury lamp may not ignite at a low temperature of 10 ° C or less, and thus must be heated before ignition, which complicates operation. In the method using a plasma ozone generator, nitric oxide can be obtained by chemical bonding of nitrogen and oxygen in the air, which can damage the components of the refrigerator or stored fruits and vegetables, and can also negatively affect the environment and workers.

[0006] In view of the foregoing, an object of the present invention is to preserve the freshness of fresh products stored in a store by effectively sterilizing all fresh products without damaging the fresh products with ozone or a radical generated by emitting ultraviolet rays.

SOLUTION OF TASKS

[0007] (1) A fresh food storage device according to some embodiments comprises: a fresh food storage capable of storing a fresh product at a temperature no lower than the refrigerated temperature; a temperature setting element capable of adjusting the internal storage temperature of the fresh food storage to a temperature no lower than the refrigerated state; an airflow generating element configured to generate airflow within the fresh food storage; an ultraviolet irradiation element configured to generate ozone or a radical by irradiating the air flow with ultraviolet rays; and an intermittent irradiation control member capable of controlling the irradiation element to irradiate the air flow with ultraviolet rays in intermittent mode.

[0008] In the above configuration, using an irradiation element that emits ultraviolet rays into the air stream, ozone or a radical, such as an OH radical, is generated around fresh products. The generated ozone or radical is scattered by the air stream throughout the interior of the fresh food storage. The entire internal area of the storehouse is sterilized with diffused ozone or radical, which reduces the growth of microorganisms such as fungi and spoilage of stored fresh products. Thus, freshness of fresh products can be maintained for a long period of time.

In addition, by emitting ultraviolet rays from the intermittent irradiation control in the intermittent mode, it is possible to control the concentration of ozone or radical generated around fresh products. By controlling the concentration of ozone or radical generated by intermittent irradiation, the oxidative damage of fresh products by ozone or radical can be reduced while maintaining the sterilizing effect on fresh products.

[0009] In addition, the temperature of the fresh food is maintained by the temperature adjusting element such that it is no lower than the refrigerated temperature, and thus, the formation of ice crystals inside the fresh food cells can be reduced. Thus, damage to the cell membrane caused by the formation of ice crystals can be reduced, and freshness of fresh products can be maintained.

In addition, using the temperature setting element adjusting the internal temperature of the fresh food storage to a temperature suitable for cooling, maintaining the temperature, or defrosting the fresh food, the fresh food storage can be used as a refrigerator, temperature storage device, or defrost unit, for example.

[0010] (2) In some embodiments, in the aforementioned configuration (1), the intermittent irradiation control element is configured to emit ultraviolet rays in an intermittent manner based on the cumulative concentration obtained by multiplying the concentration of ozone or radical by the exposure time of fresh products to ozone or radical.

It was found that the degree of oxidative action of ozone or radical, which has a sterilizing effect on fresh products, depends on the total concentration.

The time of exposure to fresh products with ozone or a radical can be substantially replaced by the time of the emission of ultraviolet rays by the irradiation element.

[0011] Ultraviolet irradiation includes continuous irradiation and intermittent irradiation. In the case of continuous exposure, the oxidative effect can be increased at a lower total concentration, but the oxidative effect may become too strong when the fresh food storage period is long, which can lead to the development of oxidative damage on the surface of the fresh food. On the other hand, in the case of intermittent irradiation, the generation of ozone or radical can be reduced, and thus, fresh products can be sterilized without damaging their surface, even if fresh products are stored for a long time.

In the case of the aforementioned configuration (2), it is possible to precisely control the generated amount of ozone or radical by intermittently emitting ultraviolet rays based on the aforementioned total concentration. Thus, it is possible to fine-tune the degree of oxidative effect on fresh products, which allows you to maintain a sterilizing effect without damaging the surface of fresh products.

[0012] (3) In some embodiments, in the aforementioned configuration (2), the intermittent irradiation control element is configured to emit ultraviolet rays in an intermittent manner while storing the fresh product in the fresh food storage, and controlling the total concentration around the fresh product in this way so that it has a value between the lower limit value at which the sterilizing effect on the fresh product occurs and the upper limit value at which the surface of the fresh product that there is oxidative damage.

In the case of the above configuration (3), during the fresh food storage period, it is possible to maintain a sterilizing effect without damaging the surface of the fresh food during the entire storage period by intermittently emitting ultraviolet rays so that the total concentration is in the range between the lower limit value and the upper limit value.

[0013] (4) In one embodiment, in any of the above configurations (1) to (3), the irradiation element comprises an excimer lamp or an inert gas fluorescent lamp capable of emitting vacuum ultraviolet rays having a single wavelength shorter than 200 nm.

By using an excimer lamp or an inert gas fluorescent lamp to irradiate air with vacuum ultraviolet rays emitted from a lamp having a single wavelength less than 200 nm, which is strongly absorbed by oxygen in air, it is possible to efficiently generate ozone or a radical from oxygen in air. Meanwhile, vacuum ultraviolet rays in the aforementioned wavelength range are not absorbed by N ₂ in air and thus do not dissociate N ₂ . Thus, NOx is not generated. Thus, there is no risk of damage to the components of the storage space of the fresh food store or of the fresh products stored therein.

[0014] In addition, an excimer lamp or an inert gas fluorescent lamp for emitting vacuum ultraviolet rays having a wavelength shorter than 200 nm is ignited regardless of temperature or humidity, so it is able to ignite quickly in a low temperature range of not more than 5 ° C, which is the storage temperature of crops, and is able to generate ozone or radical with high efficiency even in a high-humid environment, which allows sterilizing the high-humid interior of the church ilischa when the storage of fresh food is used as the thawed plant.

In addition, an excimer lamp or an inert gas fluorescent lamp quickly lights up to generate ozone or a radical at the same time as turning on the power source, and stops generating ozone or a radical while turning off the power supply, which makes it easier to control the concentration of ozone or radical.

[0015] (5) In one embodiment, in any of the aforementioned configurations (1) to (4), the temperature setting element is configured as a heating element capable of heating the fresh product to a temperature in the temperature range not higher than the protein solidification point.

In the case of the above configuration (5), using the temperature setting element heating the fresh food in the fresh food storage to a temperature in the range not higher than the protein solidification temperature (e.g. 72 ° C), the fresh food storage can be effectively used as a defrosting unit . Since the heating temperature is limited in that it will not be higher than the solidification temperature of the protein, there is no danger of changing the properties of fresh products.

[0016] (6) In one embodiment, in any of the aforementioned configurations (1) to (4), the temperature setting element is configured as a cold air generation element capable of storing the fresh product in a cold state or a refrigerated state.

Here, “cold state” refers to a state maintained at a temperature of from 2, 3 to 10 ° C, and “cold state” refers to a state maintained at a temperature of from minus 2 to 5 ° C.

In the case of the above configuration (6), by storing fresh food in a cold or chilled state, it is possible to efficiently use the fresh food storage as a refrigerator or temperature storage device.

[0017] (7) In one embodiment, in any of the above configurations (1) to (6), the fresh food storage device further includes a humidification element for humidifying the air flow around the fresh product.

In the case where the fresh products are meat, fish, vegetables, fruits, etc., the fresh products may dry out and deteriorate due to storage at low temperature. Thus, providing a humidification element can reduce drying of stored fresh products.

[0018] Furthermore, in the case of an embodiment in which fresh products are frozen with a continuous refrigerator such as a freezer, contamination of the components with fresh food residues after the freezer is operated can be prevented by installing a continuous refrigerator in a sterilized atmosphere inside the fresh food storage .

[0019] (8) A method for storing a fresh product according to some embodiments comprises: a step for storing a fresh product, wherein the fresh product is stored in a storage at a temperature not lower than the temperature of the refrigerated state; an air flow generating step in which an air flow is formed around the fresh product; and an ultraviolet irradiation step in which ozone or a radical is generated by irradiating the air flow with ultraviolet rays in a discontinuous manner and scattering ozone or a radical throughout the entire area within the storage by air flow.

[0020] In the aforementioned ultraviolet irradiation step, ultraviolet rays are emitted into the air stream inside the store, and ozone or a radical, such as an OH radical, is scattered around the fresh food, which is scattered by the air stream throughout the inner region of the fresh food store. The entire internal area of the storehouse is sterilized with diffused ozone or radical, which reduces the growth of microorganisms such as fungi and spoilage of stored fresh products. Thus, freshness of fresh products can be maintained for a long period of time.

In addition, during the ultraviolet irradiation step, ultraviolet rays are emitted in an intermittent manner, which controls the concentration of ozone or radical generated around fresh products. By controlling the concentration of ozone or radical generated by intermittent irradiation, the oxidative damage of fresh products by ozone or radical can be reduced while maintaining the sterilizing effect on fresh products.

[0021] In the fresh food storage step, the fresh food is stored at a temperature not lower than the refrigerated temperature, and thus, the formation of ice crystals in fresh food cells can be reduced, thereby reducing damage to the cell membrane caused by the formation of ice crystals , and freshness of fresh products is preserved.

[0022] (9) In one embodiment, in the aforementioned method (8), the ultraviolet irradiation step comprises the step of emitting ultraviolet rays in an intermittent manner based on the total concentration obtained by multiplying the concentration of ozone or radical by the time of irradiation with ultraviolet rays.

According to the aforementioned method (9), it is possible to control the generated amount of ozone or radical in relation to fresh products to provide a suitable amount at which the sterilizing effect can be maintained without damaging the surface of the fresh products by intermittently emitting ultraviolet rays based on the total concentration.

[0023] (10) In one embodiment, in the aforementioned method (9), the ultraviolet irradiation step comprises the step of emitting ultraviolet rays in an intermittent manner during the fresh food storage step to control the total concentration around the fresh product so that it has a value between the lower limit value at which a sterilizing effect on the fresh product occurs, and the upper limit value at which oxidative damage occurs on the surface of the fresh product.

According to the above method (10), it is possible to maintain a sterilizing effect without damaging the surface of fresh products during the entire storage period by intermittently emitting ultraviolet rays so that the total concentration is in the range between the lower limit value and the upper limit value.

[0024] (11) In one embodiment, in any of the above method (8) to (10), the ultraviolet rays are vacuum ultraviolet rays having a single wavelength less than 200 nm.

According to the aforementioned method (11), by irradiating air with vacuum ultraviolet rays having a single wavelength less than 200 nm, which is strongly absorbed by oxygen in the air, ozone or a radical can be generated efficiently. Meanwhile, vacuum ultraviolet rays in the aforementioned wavelength range are not absorbed by N ₂ in air and thus do not dissociate N ₂ . Thus, NOx is not generated. Thus, there is no risk of damage to the components of the storage space of the fresh food store or of the fresh products stored therein.

[0025] Fresh products to be stored in a warehouse include, for example, fresh vegetables, fruits, meat, and fish that have not been cooked after harvesting, or fillets or cut pieces of the aforementioned food products that are at least partially cut . Fillet with a slice (cutting surface) is more susceptible to oxidative damage by ozone or radical.

According to the aforementioned embodiments, it is possible to store the aforementioned fresh products fresh for a long period of time without oxidatively damaging the fresh products with ozone or a radical.

PREFERRED EFFECTS

[0026] According to the present invention, it is possible to efficiently sterilize all fresh products stored in a storehouse and inhibit the development of microorganisms and reduce spoilage of fresh products, keeping fresh products fresh for a long period of time, and also prevent oxidative damage to occur on the surface of fresh products.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a configuration diagram of a storage device according to one embodiment.

FIG. 2 is a configuration diagram of a storage device according to one embodiment.

FIG. 3 is a configuration diagram of a storage device according to one embodiment.

FIG. 4 is a configuration diagram of a storage device according to one embodiment.

FIG. 5 is a block diagram of a control system according to one embodiment.

FIG. 6 is a graph showing the relationship between the fresh food storage period and the appropriate total concentration.

FIG. 7 is a flowchart of a storage method according to one embodiment.

FIG. 8 is a diagram showing a sterilization test result.

FIG. 9 is a schematic sectional view of a discharge lamp according to one embodiment.

FIG. 10 is a graph showing gas chromatography of ozonated gas generated by ultraviolet irradiation.

FIG. 11 is a graph showing a change in ozone concentration of ozonized gas generated by ultraviolet irradiation.

FIG. 12 is a table showing a decrease in the number of fungal colonies by ultraviolet irradiation.

FIG. 13A is the appearance of a cabbage after harvest and before a sterilization test.

Each of FIG. 13B and 13C is the appearance of a cabbage after a sterilization test and the development of oxidative damage.

DETAILED DESCRIPTION

[0028] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. However, it is assumed that unless specifically indicated otherwise, the sizes, materials, shapes, relative positions, etc. of the components described in the embodiments should be interpreted only as illustrative and not intended to limit the scope of the present invention.

For example, an expression of relative or absolute location, such as “in direction”, “in direction”, “parallel”, “perpendicular”, “centered”, “concentric” and “coaxial”, should not be construed as indicating only the location in the exact literally, it also includes a state in which the arrangement is relatively offset by a certain tolerance, or by a certain angle or some distance, whereby it is possible to provide the same function.

For example, an expression of an equivalent state, such as “the same,” “equivalent,” or “homogeneous,” should not be construed as indicating only a state in which the feature is exactly equivalent, but also includes a state in which there is some tolerance or distinction, which can still provide the same function.

Additionally, for example, a shape expression, such as a rectangular shape or a cylindrical shape, should not be understood as a geometrically accurate shape, but also includes a shape with uneven or chamfered corners within the range in which the same effect can be achieved.

On the other hand, it is assumed that an expression such as “contain”, “include”, “have”, “enclose” and “form” does not exclude other components.

[0029] According to some embodiments, as shown in FIG. 1-4, respectively, the fresh food storage device 10 (10A, 10B, 10C, 10D) includes a fresh food storage 12, and fresh ʺfʺ products are stored inside the fresh food storage 12 at a temperature not lower than the refrigerated temperature . Inside the fresh food storage 12, a temperature setting element 14 is provided to maintain the internal temperature of the storage at a temperature no lower than the refrigerated state, and an air flow generating element 16 for generating an потокаaʺ air flow inside the storage.

In addition, an irradiation element 18 is provided for emitting ultraviolet rays inside the storage, and an irradiation element 18 emits ultraviolet rays into the air stream ʺaʺ. As shown in FIG. 5, the irradiation element 18 is provided with an intermittent irradiation control element 20. The irradiation element 18 is controlled by the intermittent irradiation control element 20 to emit ultraviolet rays in intermittent mode.

[0030] In the aforementioned configuration, using an irradiation element 18 that emits ultraviolet rays into the air stream ʺaʺ, ozone or a radical such as OH is generated around fresh свежfʺ products. The generated ozone or radical (hereinafter also referred to as “ozone and the like”) is scattered by the air stream ʺaʺ throughout the internal area of the storehouse 12 fresh products. Scattered ozone, etc. sterilizes the entire internal area of the store and reduces the growth of microorganisms such as fungi, which reduces spoilage of stored fresh products. Thus, freshness of fresh products can be maintained for a long period of time.

Furthermore, by using the irradiation element 18 controlled by the intermittent irradiation control element 20 to emit ultraviolet rays in the intermittent mode, it is possible to control the concentration of ozone and the like generated around fresh ʺfʺ products. By controlling the concentration of ozone and the like generated by intermittent irradiation, the oxidative damage of fresh products by ozone and the like can be reduced. while maintaining the sterilizing effect on fresh ʺfʺ products.

[0031] Furthermore, the fresh food temperature ʺfʺ is maintained by the temperature setting element 14 such that it is not lower than the refrigerated temperature, and thus, the formation of ice crystals inside the fresh food cells ʺfʺ can be reduced. Thus, damage to the cell membrane caused by the formation of ice crystals can be reduced, and freshness of fresh свежfʺ products can be maintained.

In addition, using the temperature setting element 14 adjusting the internal temperature of the fresh food storage 12 to a temperature suitable for cooling, maintaining the temperature, or defrosting the fresh food ʺfʺ, the fresh food storage 12 can be used as a refrigerator, temperature storage device, or defrost installation, for example.

[0032] In the embodiment shown, as shown in FIG. 1-4, the temperature setting element 14 comprises an air conditioning unit with components housed in the housing 24. The air flow generating element 16 includes a fan located inside the housing 24. The irradiation element 18 comprises a lamp unit enclosing an ultraviolet light source.

[0033] In some embodiments, the intermittent irradiation control element 20 controls the irradiation element 18 to intermittently emit ultraviolet rays based on the total concentration (hereinafter also referred to as the "CT value") obtained by multiplying the concentration of ozone and the like. at the time of exposure to fresh products ʺfʺ ozone, etc.

Fresh ʺfʺ products are damaged due to the oxidative effects of ozone, etc., if the concentration of ozone, etc. do not control. For example, crop damage occurs mainly in the form of a color change. This change occurs due to cell necrosis due to oxidation. Damage varies by crop, with greens being more likely to be damaged by oxidation caused by ozone or radicals, and fruits are less likely to be damaged by oxidation.

It was found that the oxidative effect of ozone and the like. depends on the CT value. In other words, the degree of oxidative action of ozone, etc. proportional to the CT value. The exposure time for fresh products with ozone, etc. can be substantially replaced by the time of ultraviolet radiation by the irradiation element 18.

[0034] Ultraviolet irradiation includes sequential irradiation and intermittent irradiation. Sequential irradiation has a stronger sterilizing effect on microorganisms, such as fungi, at a lower total concentration. This occurs because during intermittent irradiation, if microorganisms, such as fungi, are still alive after insufficient sterilization, microorganisms can grow over a period of time when ozone, etc. not generated. When fresh products are stored in the store 12 fresh products, it is necessary to reduce spoilage for the target period of time and preserve color, texture, etc. unchanged, and at the same time it is necessary to prevent oxidative damage by ozone, etc.

In the above embodiment, it is possible to precisely control the generated amount of ozone and the like. by intermittent emission of ultraviolet rays based on the CT value. Thus, it is possible to fine-tune the degree of oxidative effect on fresh products, which allows you to maintain a sterilizing effect without damaging the surface of fresh products.

[0035] In some embodiments, as shown in FIG. 6, the intermittent irradiation control element 20 adjusts the concentration of ozone and the like. so that it is in the range between the lower limit CT value at which sterilization is possible and the fresh поверхностьfʺ surface remains intact for the target storage period, and the upper limit CT value at which the oxidative surface develops on fresh ʺfʺ products damage.

In the case of sequential irradiation, the total concentration may exceed the upper limit CT value depending on the duration of the storage period, even if ozone, etc. has a low concentration. For example, when the ,fʺ fresh products are crops, many crops require storage for a long period of storage time, from one month to several months. Even if the concentration of ozone, etc. equal to 0.1 ppm (parts per million), then the CT value exceeds 4320 ppm * min after 30 days, and oxidative damage develops on cabbage or lettuce. However, with intermittent irradiation, the concentration can be controlled so that it is in the range between the lower limit CT value and the upper limit CT value over the entire area of the storage device.

Thus, it is possible to maintain a sterilizing effect without damaging the surface of fresh products during the entire storage period of fresh products.

[0036] In some embodiments, as shown in FIG. 1-4, the irradiation element 14 comprises an excimer lamp or an inert gas fluorescence lamp capable of emitting vacuum ultraviolet rays having a single wavelength less than 200 nm.

An excimer lamp emits vacuum ultraviolet rays with a single wavelength of less than 200 nm by means of a dielectric barrier discharge. Among the different types of excimer lamp, a xenon excimer lamp is capable of emitting vacuum ultraviolet rays having a wavelength of 172 nm, and an ArF excimer lamp is capable of emitting vacuum ultraviolet rays having a wavelength of 193 nm.

By using an excimer lamp or an inert gas fluorescent lamp to irradiate air with vacuum ultraviolet rays emitted from a lamp having a single wavelength less than 200 nm, which is strongly absorbed by oxygen in the air, ozone or a radical can be generated efficiently. Meanwhile, vacuum ultraviolet rays in the aforementioned wavelength range are not absorbed by N ₂ in air and thus do not dissociate N ₂ . Thus, NOx is not generated. Thus, there is no risk of damage to the components of the storage space of the store 12 of fresh products or fresh products stored therein.

[0037] Furthermore, an excimer lamp or an inert gas fluorescent lamp for emitting vacuum ultraviolet rays having a single wavelength shorter than 200 nm is ignited regardless of temperature and humidity, so it is able to ignite quickly in a low temperature range not more than 5 ° C, which is the storage temperature of crops, and is able to generate ozone or radical with high efficiency even in a highly humid environment, which allows sterilization of a high-humid internal anstvo store when the store 12 fresh food is used as a setting to defrost.

In addition, an excimer lamp or an inert gas fluorescent lamp is quickly ignited to generate ozone, etc. while turning on the power source, and stops generating ozone, etc. simultaneously with the cessation of power supply, which makes it easier to control the concentration of ozone, etc.

[0038] In one embodiment, the temperature setting element 14 is configured as a heating element capable of heating fresh ʺfʺ products to a temperature in the temperature range not higher than the protein solidification temperature.

According to this embodiment, using the temperature setting element 14 heating the fresh food ʺfʺ stored in the fresh food storage 12 to a temperature in the temperature range not higher than the protein solidification temperature (e.g. 72 ° C), the fresh food storage 12 can be effectively used as a defrosting unit. Since the heating temperature is limited in that it will not be higher than the solidification temperature of the protein, there is no danger of changing the properties of fresh ʺfʺ products.

[0039] In one embodiment, the temperature setting element 14 is configured as a cold air generation element capable of storing fresh ʺfʺ products in a cold state or a refrigerated state.

In this embodiment, by storing fresh ʺfʺ products in a cold or chilled state, the fresh food storage 12 can be effectively used as a refrigerator or temperature storage device.

[0040] In some embodiments, as shown in FIG. 3 and 4, a humidification element 22 is additionally provided for humidifying the air flow ʺa потока around the fresh products ʺfʺ.

In the case where the fresh products are meat, fish, vegetables, fruits, etc., the fresh products may dry out and deteriorate due to storage at low temperature. Thus, the provision of the moistening element 22 can reduce the drying of the stored food ʺfʺ.

In an illustrative embodiment, as shown in FIG. 3 and 4, the humidification element 22 includes a water storage tank 32 at the bottom of the housing 24, and a spray device 34 for supplying the moisturizing water ʺwʺ upward from the water storage tank 32 and spraying the moisturizing water ʺwʺ in the air flow passage ʺbʺ formed inside the housing 24 .

[0041] In an illustrative embodiment, as shown in FIG. 1-4, the temperature setting element 14 includes, inside the housing 24 having an inlet and an outlet for the air flow ʺaʺ, a cold air generating element 16 comprising a fan, a heater 26 for defrosting and setting the temperature, and a heat exchanger 30 provided with a refrigerant from the freezer 28 located outside the storage. An air flow passage ʺbʺ is formed inside the housing 24, and an air flow ʺaʺ is formed inside the air flow passage ʺbʺ. The air stream ʺaʺ is heated by the heater 26 or cooled by the heat exchanger 30, and as a result, the temperature of the air stream ʺaʺ is adjusted.

[0042] In the embodiment shown in FIG. 1 and 2, the housing 24 is laterally arranged, and the air flow ʺaʺ flows laterally inside the housing 24. In the embodiment shown in FIG. 3 and 4, the housing 24 is located vertically, and the air flow ʺaʺ flows vertically inside the housing 24.

The freezer 28 is located outside the fresh food storage 12, for example, on the upper wall of the fresh food storage 12, as shown in FIG. 1 and 2, or adjacent to the side wall of the fresh food storage 12, as shown in FIG. 3 and 4.

[0043] In one embodiment, as shown in FIG. 5, the irradiation element 18 comprises a gas discharge lamp 35 comprising a xenon excimer lamp or an inert gas fluorescent lamp. The gas discharge lamp 35 includes, for example, a gas discharge lamp light source 36 for emitting vacuum ultraviolet rays having a wavelength shorter than 200 nm, and a fan 38 for scattering ozone and the like generated by vacuum ultraviolet rays emitted from the gas discharge lamp source 36 of light. Fan 38 may be omitted.

In an illustrative embodiment, the discharge lamp 35 is facing the air stream ʺaʺ formed inside the fresh food storage 12 and includes an ultraviolet irradiation window 40.

The gas-discharge tube light source 36 emits vacuum ultraviolet rays towards the air stream потокaʺ, and as a result, ozone and the like. generated in the air stream ʺaʺ, and generated ozone, etc. carried by ʺaʺ airflow for dispersion throughout the entire internal area of the repository, thus sterilizing fresh ʺfʺ products.

[0044] The wavelength of the ultraviolet rays emitted from the discharge lamp depends on the discharge gas sealed in the discharge chamber. For example, the wavelength is 126 nm when the discharged gas is argon (Ar), 146 nm when the discharged gas is krypton (Kr), and 172 nm when the discharged gas is xenon (Xe).

[0045] In the embodiment shown in FIG. 1 and 3, the gas discharge lamp serving as the irradiation element 18 is located above the fresh ʺfʺ products, and the ultraviolet irradiation window 40 is oriented so that it faces the fresh ʺfʺ products through the потокаaʺ air flow.

In the embodiment shown in FIG. 2, the discharge lamp 35 is located above the continuous supply freezer 44, and the ultraviolet irradiation window 40 is oriented so that it faces the continuous freezer 44 through the air flow ʺaʺ.

In the embodiment shown in FIG. 4, the discharge lamp 35 is located in the corner above the fresh продуктовfʺ products, and the ultraviolet irradiation window 40 is oriented so that it faces the потокaʺ airflow.

As described above, the ultraviolet window 40 is positioned so that it faces the air stream потокaʺ, and as a result, generated ozone and the like can be scattered. throughout the entire area within the vault through ʺaʺ airflow. Thus, the entire area within the vault can be sterilized.

[0046] In an illustrative embodiment, as shown in FIG. 1-3, the ultraviolet irradiation window 40 is positioned so that it faces the fresh ʺfʺ products, and thus, the ultraviolet rays are incident directly on the fresh ʺfʺ products, thereby achieving a high sterilization efficiency with respect to the irradiated surface of the fresh ʺfʺ products. Thus, the synergistic effect of vacuum ultraviolet rays emitted from the discharge lamp 35 enhances the sterilizing effect on all stored fresh products.

[0047] In an illustrative embodiment, as shown in FIG. 1-3, the discharge lamp 35 emits vacuum ultraviolet rays toward the air stream ʺaʺ passing through the air stream потокаbʺ formed inside the housing 24 of the temperature setting element 14, and thus, generated ozone and the like. can be efficiently dispersed throughout the entire area inside the storage facility through ʺaʺ airflow. Thus, it is possible to effectively sterilize all the air inside the store.

In addition, the temperature setting element 14 has a humidification element 22, which humidifies the air flow ʺaʺ introduced into the temperature setting element 14, and as a result of this, a highly humid atmosphere can be stored inside the storage and the drying of fresh ʺfʺ products can be suppressed. Thus, a reduction in the yield of fresh ихfʺ products can be reduced.

[0048] In an illustrative embodiment, as shown in FIG. 1, 3, and 4, fresh ʺfʺ products are whole or sliced vegetables or fruits, and are placed in baskets 42 stacked inside a storehouse of 12 fresh products.

[0049] In one embodiment, as shown in FIG. 2, a continuous-flow freezer 44 is located inside the fresh food storage 12. The continuous-supply freezer 44 includes a conveyor 46, and fresh ʺfʺ products are frozen continuously during transport by the conveyor 46.

In this embodiment, fresh ʺfʺ products are frozen inside the fresh food storage 12 having a sterilizing effect due to the presence of ozone and the like, and thus, it is possible to prevent contamination of the components of the freezer 44 with a continuous supply of fresh food residues after completion of work freezer 44 continuous feed.

[0050] In one embodiment, as shown in FIG. 5, an ozone concentration sensor 48 for detecting an ozone concentration or the like is located inside the fresh food storage 12, and the value detected by the ozone concentration sensor 48 is input to the intermittent irradiation control element 20. The intermittent irradiation control element 20 controls the operation of the discharge lamp 35 based on the aforementioned detected value.

[0051] As shown in FIG. 7, the storage method according to some embodiments includes a fresh food storage step S10, an airflow formation step S12, and an ultraviolet irradiation step S14.

In the fresh food storage step S10, the fresh food ʺfʺ is stored inside the fresh food storage 12 at a temperature not lower than the refrigerated temperature. In step S12 of forming an air flow, an air stream ʺaʺ is formed around the fresh products ʺfʺ stored in the fresh food storage 12. In the ultraviolet irradiation step S14, the air stream ʺaʺ is irradiated continuously in the ultraviolet rays to generate ozone or a radical such as an OH radical, and ozone and the like. итсяaʺ is carried by the air stream for dispersion over the entire area inside the storage.

[0052] Thus, ozone and the like, scattered throughout the entire area inside the store, sterilizes the entire area inside the store and reduces the growth of microorganisms such as fungi, thereby reducing spoilage of stored fresh ʺfʺ products. Thus, freshness of fresh products can be maintained for a long period of time.

In addition, in the ultraviolet irradiation step S14, the ultraviolet rays are emitted in an intermittent manner, which controls the concentration of ozone or radical generated around fresh ʺfʺ products. By controlling the concentration of ozone and the like generated by intermittent irradiation, the oxidative damage of fresh ʺfʺ products by ozone and the like can be reduced. while maintaining the sterilizing effect on fresh ʺfʺ products.

In the fresh food storage step S10, the fresh ʺfʺ products are stored at a temperature not lower than the refrigerated temperature, and thus it is possible to reduce the formation of ice crystals in fresh ʺfʺ cells and to reduce the damage to the cell membrane caused by the formation of ice crystals, and to preserve естьfʺ fresh food freshness.

[0053] In one embodiment, in the ultraviolet irradiation step S14, ultraviolet rays are emitted in an intermittent manner based on the total concentration obtained by multiplying the time of ultraviolet emission by the concentration of ozone and the like.

You can control the amount of ozone generated, etc. with respect to fresh ʺfʺ products, to ensure a suitable amount at which the sterilizing effect can be maintained without damaging the surface of fresh ʺfʺ products by intermittently emitting vacuum ultraviolet rays based on the total concentration.

[0054] In one embodiment, in the ultraviolet irradiation step S14, the ultraviolet rays are emitted intermittently and the total concentration around the fresh products ʺfʺ is controlled so that it has a value between the lower limit value at which the sterilizing effect on the fresh products ʺfʺ occurs , and the upper limit value at which oxidative damage occurs on the surface of fresh ʺfʺ products.

The sterilizing effect can be maintained without damaging the surface of fresh свежfʺ products during the entire storage period by intermittently emitting ultraviolet rays so that the total concentration is in the range between the lower limit CT value and the upper limit CT value.

[0055] In one embodiment, in the ultraviolet irradiation step S14, vacuum ultraviolet rays having a wavelength range of less than 200 nm are emitted.

By irradiating air with vacuum ultraviolet rays having a single wavelength of less than 200 nm, which is strongly absorbed by oxygen in the air, ozone or a radical can be generated efficiently. Meanwhile, vacuum ultraviolet rays in the aforementioned wavelength range are not absorbed by N ₂ in air and thus do not dissociate N ₂ . Thus, NOx is not generated. Thus, there is no risk of damage to the components of the storage space of the storehouse 12 of fresh products or fresh ʺfʺ products stored therein.

[0056] In the illustrative embodiment, the fresh ʺfʺ products are vegetables or fruits, refrigerated in the fresh food storage to a temperature of not less than 0 ° C and not more than 5 ° C, and the ozone concentration is adjusted so that it is not less than 0.1 ppm and not more than 0.5 ppm Thus, spoilage of fresh ʺfʺ products during the storage period of fresh ʺfʺ products can be reduced and oxidative damage to ozone and the like can be reduced.

Additionally, the fresh food storage is humidified inside, and the relative humidity is adjusted so that it is not less than 90%. Thus, the drying of fresh ʺfʺ products during the storage period can be reduced.

[0057] In one embodiment, among vegetables and fruits, leafy vegetables having thin epidermal cells such as lettuce and cabbage, flowers and mushrooms are easily exposed to oxidative damage by ozone and the like. Thus, during the storage period, the above leafy vegetables and the like. irradiated intermittently with vacuum ultraviolet rays of the aforementioned wavelength so that the CT value is greater than the lower limit of the CT value and closer to the lower limit of the CT value compared to whole skin-coated fruits such as tomatoes or lemons .

Thus, oxidative damage to leafy vegetables, flowers, and mushrooms can be reduced, especially on their slices and their periphery, during the storage period.

[0058] In one embodiment, in the case where the fresh food ʺfʺ is fresh fish meat, or other fresh chicken or turkey meat, for example, and the meat in a piece of fillet is cut in a direction that at least partially intersects with the cell membrane, the meat easily exposed to oxidative damage by ozone, etc. Thus, in the case of the aforementioned fillet, the fillet is irregularly irradiated with vacuum ultraviolet rays of the aforementioned wavelength so that the CT value is larger than the lower limit of the CT value and closer to the lower limit of the CT value compared to a piece of fillet cut in the direction along the cell membrane during the storage period.

Thus, oxidative damage to the fillet, which is easily affected by oxidative damage by ozone, and the like, can be reduced.

[0059] In one embodiment, when the fresh ʺf продуктами products are fresh fish meat, or other fresh chicken or turkey meat, for example, and the meat is at least partially cut in the direction along the cell membrane, the meat is not easily exposed to oxidative damage by ozone, etc., compared with a piece of fillet cut in a direction intersecting with the cell membrane. Thus, in the case of the aforementioned fillet, the fillet is irregularly irradiated with vacuum ultraviolet rays of the aforementioned wavelength so that the CT value is smaller than the upper limit of the CT value and closer to the upper limit of the CT value.

Thus, it is possible to improve the sterilizing effect and at the same time reduce the oxidative damage of the aforementioned fillets.

EXAMPLE OF USE

[0060] (1) Testing the sterilization of the interior of the vault

The storage device 10 (10D) shown in FIG. 4, is used as a storage device. The storage device 10 (10D) includes a fresh food storage 12 including a temperature setting element 14 having a humidification element 22.

As shown in FIG. 4, the gas discharge lamp 35 serving as the irradiation element 18 is located in the corner above the fresh ʺfʺ products, and the ultraviolet irradiation window 40 is oriented so that it faces the потокaʺ airflow.

Vacuum ultraviolet rays having a wavelength shorter than 200 nm were emitted through the ultraviolet irradiation window 40, and a sterilization test was performed with respect to the air of the interior of the storage, while maintaining the inside of the storage at a temperature of 2 ° C and a relative humidity of 95% or higher.

Additionally, the discharge lamp 35 was fired intermittently by the intermittent irradiation control element 20 for 30 minutes, while it was repeatedly turned on for one second and turned off for ten seconds, so that the ozone concentration in the storage became 0.3 ppm.

[0061] As shown in FIG. 4, inside baskets 42 stacked below the discharge lamp 35, potato dextrose agar (PDA medium) was exposed for 30 minutes to measure the number of mushrooms at points A and B in the upper position, and at point C in the middle position .

As shown in FIG. 8, the reduction in the number of bacteria is confirmed based on the test results after the sterilization operation.

In a comparative example, using an ultraviolet lamp containing a mercury lamp and configured to emit ultraviolet rays at a wavelength of 185 nm, the mercury lamp could not light due to the low temperature.

[0062] (2) Storage Test of Cabbage

In the case of the storage device 10 (10D) shown in FIG. 4, the cabbage was placed uncoated in a storehouse of 12 fresh products, and stored for two months at a temperature of 2 ° C and a relative humidity of 95% or higher. After 38 days of storage, intermittent irradiation was performed for the rest of the time using a discharge lamp 35 to emit ultraviolet rays having a wavelength shorter than 200 nm for one hour per day, and the lamp was turned on for one second at intervals equal to ten seconds, so that the concentration of ozone inside the storage became 0.3 ppm.

In a comparative example, cabbage was stored for two months under the same conditions, except that the discharge lamp 35 did not work.

[0063] As a result, in the use example, spoilage was kept low for two months. In contrast, in the comparative example, good freshness was maintained for 40 days, but then mushrooms developed and rapid spoilage was observed.

The rate of mushroom formation after two months was 27% in the use case and 90% in the comparative example, which shows a big difference. Mass output was also greater in the use case.

[0064] (3) Test for surface sterilization of cabbage

A cooling unit (temperature setting element) 14, including a humidification element 22, was placed inside the container, and a discharge lamp 35 was placed on the outlet of the cooling unit 14. While the temperature and relative humidity inside the container were kept at 5 ° C and 90% or higher, the gas discharge lamp 35 was controlled so that it turned on for one second and turned off for ten seconds and at the same time emitted vacuum ultraviolet rays having a wavelength less than 200 nm during the irradiation time Equal to two hours a day for ten days, so that the concentration of ozone was 0.35 hr. / Mn.

As a result, the number of ordinary bacteria and fungi on the surface and stem of cabbage has decreased significantly.

[0065] (4) Test for discoloration of cabbage (comparative example)

Using the same test device as in the aforementioned test (3), the temperature and relative humidity inside the container were set to the same values as in the aforementioned test (3), and the discharge lamp 35 was controlled so that the ozone concentration around cabbage, fresh product, it became equal to 2 ppm. The gas discharge lamp 35 was adjusted so that it turned on for one second and turned off for 1.5 seconds and worked continuously for 24 hours, 9 days. As a result, the surface color of the cabbage has changed.

[0066] <Testing the produced gas>

As shown in FIG. 9, a gas discharge lamp 35 serving as an irradiation element 18, according to one embodiment, is configured such that vacuum ultraviolet rays emitted from the discharge chamber 36a containing the discharge gas are not absorbed by the N ₂ gas in the atmosphere introduced into the space c , and do not dissociate gas N ₂ . Thus, nitric oxide generation can be reduced.

FIG. 10 shows the result of an analysis of ozonized gas by gas chromatography, where the ozonated gas was generated by a discharge lamp that emits vacuum ultraviolet rays having a wavelength of 172 nm using xenon as the discharge gas. In the drawing, line D represents the case where the aforementioned discharge lamp was used, and line E represents the case where ozonated gas was generated using a well-known discharge ozonizer. As shown in FIG. 10, line D indicates that nitrogen oxide generation has been reduced.

[0067] (5) Mushroom Irradiation Test

The inside of the incubator was maintained at a temperature of 20 ° C and a relative humidity of 90%, and penicillus was used as a test strain. 10 ml of sterilized water was added to the penicillin mycelium, and the spores were scraped off and diluted to various degrees of dilution. Diluted spores having different degrees of dilution were introduced into the PDA medium, 100 μl in all cases and placed in an incubator. The PDA medium was intermittently irradiated with vacuum ultraviolet rays having a wavelength shorter than 200 nm emitted by a gas discharge lamp repeatedly turned on for one second with an interval of ten seconds.

FIG. 11 is a graph showing changes in ozone concentration inside an incubator. The maximum ozone concentration in FIG. 11 are called “processing sections” in FIG. 12. FIG. 12 shows that the number of fungal colonies (clusters) decreases with an increase in the number of treatment sections, namely, CT values.

[0068] Under the above test conditions, the test was performed with additional test strains of cladosporium and escherichia coli (Escherichia coli). The CT value was adjusted so that it was 13.3 ppm * min (day 1), 36.8 ppm * min (day 2), 42.5 ppm * min (day 3).

As a result, all three test strains decreased, and in particular, Escherichia decreased significantly.

[0069] (6) Storage Test for Cabbage

Harvested cabbage was stored in a store where the temperature was kept at 2 ° C, and cabbage inside the store was irradiated with vacuum ultraviolet rays having a wavelength shorter than 200 nm emitted by a discharge lamp that was turned on for 0.5 seconds and turned off for 20 seconds in intermittent operation for 30 minutes. The target ozone concentration was 0.35 ppm. After intermittent irradiation for 30 minutes, the CT value became 11.1 ppm * min. This intermittent irradiation was performed twice a day, and the CT value was 610.5 ppm * min after 28 days.

After 63 days of storage, only a small number of mushrooms developed on the cabbage, and spoilage was reduced, and the cabbage did not contain oxidative damage by ozone. Thus, this test shows that the CT value was between the lower limit value and the upper limit value during storage of the cabbage.

[0070] (7) Storage Test for Cabbage

Harvested cabbage was stored in a store where the temperature was kept at 2 ° C, and cabbage inside the store was irradiated with vacuum ultraviolet rays having a wavelength shorter than 200 nm emitted by a discharge lamp that was turned on for 0.5 seconds and turned off for 20 seconds in intermittent operation for 60 minutes. The target ozone concentration was 0.35 ppm. FIG. 13A shows the appearance of a cabbage after harvest and before testing.

After the start of the test, intermittent irradiation for 60 minutes was performed twice a day for 29 days. The CT value after 29 days reached 2919.53 ppm * min, and oxidative damage developed on the whole cabbage (first stage). FIG. 13B shows the appearance of a cabbage in this state. In FIG. 13B, oxidative damage “o” is present on the surface of the cabbage.

After the first stage, the intermittent irradiation time was changed to a time of 30 minutes once a day, irradiation was continued for another 29 days (second stage). The CT value in the second stage reached 1101.18 ppm * min, and, as a result, the CT value from the beginning of the test to the second stage reached 3930.72 ppm * min. After the second stage, as shown in FIG. 13C, the appearance of the cabbage shows oxidative damage “o”, which has become more serious.

[0071] The above test was performed with cabbage divided into three groups, and all groups showed oxidative burnup after the first stage.

The result of the above test shows that it is necessary to set the upper limit CT value equal to 2900 ppm * min or less.

Additionally, after the first stage, the mushroom generation rate was 20% in group X, 10% in group Y, and 10% in group Z. Additionally, after the second stage, the mushroom generation rate was 100% in group X, 57% in group Y , and 74% in group Z. The cause of progress in the development of fungi can be oxidative damage due to irradiation with ozone and the like, which exceeds the upper limit CT value.

Ozone, etc. can sterilize fungi on the surface of fresh products, but cannot remove all fungi that develop in a complex organization, such as leaves, because the osmotic ability of ozone, etc. is low. Leaves that are dead due to oxidative damage by ozone, etc., eventually deteriorate, and fungi develop on them.

[0072] While the internal temperature of the fresh food store is set to 0 ° C or higher in each of the above embodiments, the present invention can also have a sterilizing effect and an effect for suppressing oxidative damage to the fresh food store having a lower internal temperature lower than than 0 °.

INDUSTRIAL APPLICABILITY

[0073] According to some embodiments, it is possible to sterilize all fresh products stored in the store effectively without damaging the components of the fresh food store or stored fresh products even when irradiated with ultraviolet rays, and to reduce the development of microorganisms and reduce spoilage of fresh products while maintaining fresh fresh products for a long period of time.

DESCRIPTION OF REFERENCE POSITIONS

[0074]

10 (10A, 10B, 10C, 10D) storage device

12 fresh food storage

14 temperature setting item

16 airflow generating element

18 exposure element

20 intermittent exposure control

22 moisturizing element

24 building

26 heater

28 freezer

30 heat exchanger

32 water storage tank

34 spray device

35 discharge lamp

36 gas discharge tube light source

38 fan

40 UV window

42 basket

44 continuous-flow freezer

46 conveyor

48 ozone concentration sensor

a air flow

b airflow channel

f fresh product

o oxidative damage

w moisturizing water

Claims (27)

1. A device for storing fresh products, containing: fresh food storage, designed to store fresh food at a temperature not less than the temperature of the refrigerated state; a temperature setting element capable of adjusting the internal storage temperature of the fresh food storage to a temperature no lower than the refrigerated state; an airflow generating element configured to generate airflow within the fresh food storage; an irradiation element configured to generate ozone or a radical by irradiating the air stream with ultraviolet rays; and intermittent irradiation control element for controlling the irradiation element for irradiating the air flow with ultraviolet rays in intermittent mode. 2. A device for storing fresh products according to claim 1, in which the intermittent irradiation control element is configured to emit ultraviolet rays in an intermittent manner based on the total concentration obtained by multiplying the concentration of ozone or radical by the exposure time of fresh products to ozone or radical. 3. A device for storing fresh products according to claim 2, wherein the intermittent irradiation control element is configured to emit ultraviolet rays in an intermittent manner while storing the fresh product in the fresh food storage and controlling the total concentration around the fresh product so that it has a value between the lower limit value at which the sterilizing effect on the fresh product, and the upper limit value at which oxidative damage occurs on the surface of a fresh product. 4. A device for storing fresh products according to any one of paragraphs. 1-3, wherein the irradiation element comprises an excimer lamp or an inert gas fluorescent lamp capable of emitting vacuum ultraviolet rays having a single wavelength of less than 200 nm. 5. A device for storing fresh products according to any one of paragraphs. 1-4, in which the temperature setting element is made in the form of a heating element capable of heating the fresh product to a temperature in the temperature range not higher than the protein solidification point. 6. A device for storing fresh products according to any one of paragraphs. 1-4, in which the temperature setting element is made in the form of a cold air generating element capable of storing the fresh product in a cold state or a cooled state. 7. A device for storing fresh products according to any one of paragraphs. 1-6, further comprising a humidification element for humidifying the air flow around the fresh product. 8. A method of storing fresh product, including: a fresh product storage step of storing the fresh product in the storage at a temperature not lower than the refrigerated state; an air flow generating step in which an air flow is formed around the fresh product; and an ultraviolet irradiation step in which ozone or a radical is generated by irradiating the air flow with ultraviolet rays in a discontinuous mode and scattering ozone or a radical throughout the entire area inside the storage by air flow. 9. The method of storing fresh product according to claim 8, wherein the ultraviolet irradiation step comprises intermittently emitting ultraviolet rays based on the total concentration obtained by multiplying the concentration of ozone or radical by the time of ultraviolet irradiation. 10. The method of storing fresh product according to claim 9, wherein the ultraviolet irradiation step comprises intermittently emitting ultraviolet rays during the fresh food storage step to control the total concentration around the fresh product so that it has a value between the lower limit value at which a sterilizing effect on the fresh product occurs , and the upper limit value at which oxidative damage occurs on the surface of a fresh product. 11. A device for storing fresh products according to any one of paragraphs. 8-10, in which the ultraviolet rays are vacuum ultraviolet rays having a single wavelength less than 200 nm.

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