JP2006204106A - Method for sterilizing crop and apparatus for sterilizing crop - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for improving sterilizing effect and a sterilizing apparatus suitable for practicing such sterilizing method in the sterilizing method using ozone. <P>SOLUTION: The method for sterilizing crops comprises a step (a) for depressurizing an atmosphere in which a material to be sterilized is stored and a step (b) for feeding ozone to the material to be sterilized stored in the depressurized atmosphere. The present invention can obtain remarkable effect when the material to be sterilized is a seed or a bulb. In the step (a), the atmospheric pressure in which the material to be sterilized is stored is preferably ≤100 Torr, further preferably ≤50 Torr. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for sterilizing crops such as seeds such as seed pods, bulbs, vegetables, and fruits, and more particularly to a highly efficient sterilization method and apparatus using ozone water.

  Since the main diseases of paddy rice and vegetables are transmitted by seeds, seed disinfection is indispensable for growing rice seedlings. In seed disinfection, several types of drugs are used in combination to prevent bacterial disease, fungal disease, and nematode disease. However, if the same type of drug is used continuously, resistant bacteria are generated and are not effective in preventing disease. Furthermore, the treatment of the waste liquid of the chemical solution requires a considerable processing cost, and development of a labor-saving sterilization method that does not use a chemical is desired.

As a countermeasure, a hot water sterilization method has been developed for seed potatoes.
In this hot water sterilization method, first, salt water selection is performed. In this salt water selection, defective seeds floating in salt water having a specific gravity of 1.13 or more are screened out. This will also prevent disease transmission.
Next, wash with water and drain. In order to prevent salt damage, the seed pods are washed thoroughly with water to remove salt from the seed pods.
Subsequently, air drying is performed. In air drying, after draining thoroughly, the seed pods are spread in the sun and dried to about 15% moisture. This is because, when the hot water treatment is performed, the sterilizing effect is greatly reduced unless the seed pods are dried.
Next, the bag is packed. Dried seed pods are put in a bag, but if it is put too much, the temperature will not rise uniformly to the inside of the bag, and it will cause a decrease in sterilization effect and germination unevenness.
Sterilization is performed by immersing the seed pods in hot water, for example, at 60 ° C. for 10 minutes in a packaged state. When the temperature is raised too much, germination damage is caused, and when the temperature is low, the bactericidal effect is lost.
Finally, after sterilization with hot water, the seed potatoes are immediately cooled with tap water. Otherwise, it will be steamed rice and cannot be used as a seed meal.

Hot water sterilization is very difficult to control, and the sterilization rate of hot water sterilization is about 60%, and a sufficiently high sterilization rate cannot be obtained. Therefore, a sterilization method using ozone water has recently been proposed. . For example, Patent Document 1 (Japanese Patent Laid-Open No. 5-21808) and Patent Document 2 (Japanese Patent Laid-Open No. 9-510081).
Patent Document 1 proposes to immerse seeds in ozone water having an ozone concentration of 5 ppm or more. Patent Document 2 proposes that the water content of the seed or bulb is adjusted to a range of 5 to 60% with respect to the weight of the seed or bulb and then sterilized with ozone water.

Japanese Patent Application Laid-Open No. 5-21808 Japanese National Patent Publication No. 9-510081

  As described above, it is required to further improve the sterilization effect by the sterilization method using ozone water disclosed in Patent Document 1 and Patent Document 2. This invention is made | formed based on such a technical subject, and it aims at providing the method of improving the sterilization effect in the sterilization method using ozone. Furthermore, this invention aims at provision of the sterilizer suitable for implementing such a sterilization method.

  It is said that 99.9% or more of the pathogenic bacteria present in the seed pod exist in the space between the rice husk, which is the epidermis, and the pericarp. The remaining fungi are also present in the flesh quality near the skin surface. According to the study by the present inventors, since air is present in this gap portion, it is difficult for ozone water to enter the gap portion even if it is immersed in ozone water. Therefore, a sufficient sterilizing effect cannot be obtained only by immersing in ozone water. Moreover, since the outer surface of the rice husk has irregularities, even if the seed pods are immersed in ozone water, air is entrained in the irregularities, so that the surface has water repellency. Therefore, a sufficient sterilizing effect cannot be obtained only by soaking in ozone water. As a result, the sterilization rate is about several tens of percent in the sterilization treatment that is simply immersed in ozone water.

Therefore, the present inventors examined exposing the seed pods to a reduced-pressure atmosphere for the purpose of sufficiently immersing ozone water in the space between the rice husk and the pericarp and further removing the water repellency of the rice husk surface. . Then, after exposing the soot to a reduced pressure atmosphere and then supplying ozone water under the reduced pressure atmosphere, it was found that the sterilization efficiency can be significantly improved. Moreover, this effect is naturally expected not only in ozone water but also in the case of using ozone gas.
This invention is based on the above knowledge, The step (a) which decompresses the atmosphere in which the sterilization target object was accommodated, The step (b) which supplies ozone to the sterilization target object accommodated in the pressure-reduced atmosphere, , A method for sterilizing agricultural crops. In the present invention, when seeds or bulbs are sterilization objects, it is easy to obtain an effect of improving the sterilization rate. This is because seeds or bulbs have a portion that is difficult for ozone gas or ozone to enter, among crops.

  In the step (a) of the present invention, it is preferable that the atmosphere in which the sterilization object is accommodated has a vacuum degree of 100 torr or less, and further a vacuum degree of 50 torr or less. By setting it as such an atmosphere, the effect of sterilization improves.

  In step (b) of the present invention, ozone water having an ozone concentration of 0.5 to 40 ppm is preferably supplied as ozone, and the bubble diameter of ozone gas in the ozone water is preferably 50 μm or less. In the step (b) of the present invention, it is preferable to immerse the sterilization object in ozone water for 1 minute or more. Furthermore, in the step (b) of the present invention, it is preferable to stir the ozone water in which the object to be sterilized is immersed.

The present invention provides the following sterilization apparatus for performing the above sterilization method. This sterilization apparatus for agricultural products includes a processing container having a storage space for an object to be sterilized and in which the sterilization process for the object to be sterilized is performed in the storage space, a decompression unit having the storage space as a reduced-pressure atmosphere, and ozone water in the processing container. And an ozone water supply unit for supplying water.
In this sterilization apparatus, ozone water may be supplied into the processing container by the ozone water supply unit after the inside of the accommodation space is brought into a predetermined reduced pressure state by the pressure reduction unit.

  The ozone water supply unit of the present invention preferably includes a bubble refining unit for refining bubbles of ozone gas in ozone water. Moreover, it is preferable that a processing container is provided with the stirring part which stirs ozone water.

  Hot water treatment has been developed due to the adverse effects of conventional chemical sterilization, but its sterilization rate is about 60%. Further, the sterilization rate is about 90% by simply immersing in ozone water, but by applying the present invention, the sterilization rate can be made 99.9% or more.

Hereinafter, an embodiment of the present invention will be described on the premise that ozone is supplied from ozone water to an object to be sterilized.
<Sterilization method>
The present invention includes a step (a) of depressurizing an atmosphere in which an object to be sterilized is housed, and a step (b) of supplying ozone to the object to be sterilized housed in the decompressed atmosphere.
The reason why the present invention decompresses the atmosphere in which the object to be sterilized is stored in step (a) is to improve the sterilizing effect by ozone water. More specifically, as described above, in the case of seed pods, ozone water can be sufficiently infiltrated into the gap between the rice husk and the skin, and the water repellency on the surface of the rice husk can be removed. Here, seed pods are taken as an example, but the same effect can be obtained for seeds and bulbs having epidermis and flesh. The seeds can be applied to various kinds of seeds such as corn, kidney beans, barley, and sunflower. Moreover, as a bulb, it can apply to various things, such as an iris, a tulip, a gladiolus, a hyacinth.

FIG. 1 shows the relationship between the degree of vacuum (torr) and the viable cell rate (−) when the viability (viable cell rate) of the bacteria before and after the immersion is measured when the seed pod is immersed in ozone water under the following conditions. It is a graph to show. As shown in FIG. 1, it can be seen that the viable cell rate decreases as the pressure is reduced from atmospheric pressure (760 torr). In particular, it can be seen that the viable bacteria ratio is significantly reduced by setting the atmosphere in which the soot is stored to a vacuum level of 100 torr or less. Moreover, the viable cell rate can be reduced to 10 ⁻³ or less (bactericidal rate 99.9%) by setting the atmosphere in which the soot is stored to a vacuum level of 50 torr or less.

  From the results shown in FIG. 1 above, the effect of the present invention can be enjoyed if the atmosphere containing the sterilization object is decompressed, but preferably the atmosphere containing the sterilization object is 100 torr or less. Set the degree of vacuum. More preferably, the atmosphere in which the object to be sterilized is accommodated has a vacuum level of 50 torr or less. However, if the atmosphere in which the object to be sterilized (for example, soy sauce) is accommodated at a vacuum level of 20 torr or less, the object to be sterilized may be dried to cause germination damage. Therefore, in the case of an object to be sterilized in which a problem due to drying is a concern, it is preferable that the atmosphere in which the object to be sterilized (for example, seeds) is accommodated has a vacuum degree of 20 torr or more.

  Conditions: 50 g of rice seedling blight contaminated pods were placed in a 10 L sterilization tank. After the inside of the sterilization tank was set to a vacuum degree of 760 torr (atmospheric pressure), 100 torr and 20 torr, 5 L of ozone water having a concentration of 10 ppm was supplied to the sterilization tank and left as it was for 20 minutes. After 20 minutes, the seed meal was taken out and the number of remaining bacteria was measured by a culture method. The ratio of the number of remaining bacteria to the initial number of bacteria (number / g) is defined as the viable cell rate (-), and the relationship with the degree of vacuum is shown in FIG.

This invention implements the step (b) which supplies ozone water to the sterilization target object accommodated in the pressure-reduced atmosphere after a step (a).
The atmosphere to which ozone water is supplied has a reduced pressure, preferably a vacuum degree of 100 torr or less, more preferably a vacuum degree of 50 torr or less. Therefore, taking the seed rice as an example, the air in the space between the rice husk and the skin and the air on the surface of the rice husk are removed. Therefore, ozone water can easily contact and infiltrate between the rice husk and the pericarp and the surface of the rice husk, so that a high bactericidal effect can be obtained. Furthermore, ozone water penetrates into the brown rice cells through the pores of the brown rice cells, sterilizes pathogenic bacteria inside the seed pods, and enhances the sterilizing effect inside the seeds. Also, in the case of an object to be sterilized other than the seed potato, since the air layer on the surface of the object to be sterilized can be removed, the contact of ozone water with the surface becomes close and the sterilizing effect can be improved.

  The supply method of the ozone water in step (b) does not matter. Typically, ozone water may be supplied so that an object to be sterilized can be immersed, but the present invention is not limited to this form as long as the effect of the present invention can be obtained. For example, ozone water may be showered and continuously sprayed on the sterilization target.

  Even after supplying ozone water to the sterilization target housed in the decompressed atmosphere, it is preferable to maintain the decompressed state of the atmosphere until the sterilization treatment is completed. This is to obtain the effect of improving the sterilization rate according to the present invention. However, it goes without saying that even if the atmosphere is returned to atmospheric pressure during the sterilization treatment, the sterilization rate can be improved as compared with the method of simply immersing the object to be sterilized in ozone water.

In the ozone water used in the present invention, it is preferable that the bubble diameter of the ozone gas contained is as fine as 50 μm or less. This is because, if the bubble diameter of ozone gas is small, it becomes easy to diffuse the object to be sterilized, for example, seed pods, and the sterilizing effect is improved. A more preferable bubble diameter of ozone is 40 μm or less, and a more preferable bubble diameter of ozone is 30 μm or less.
In order to obtain ozone water having a small bubble diameter of ozone, ozone gas generated by the ozone gas generator may be dissolved in water by the fine bubble generator. At that time, if the bubble diameter is reduced to nano-order, the same permeability as water can be obtained.
In addition, when ozone gas is completely dissolved in water, there are no bubbles, and it is most preferable to use such ozone water in order to obtain the effects of the present invention.

  In the present invention, ozone water is supplied to the object to be sterilized after the step (a), so that a predetermined sterilizing effect can be obtained even with ozone water having a low concentration. Therefore, although the ozone water concentration is not limited in the present invention, the concentration is preferably 0.5 ppm or more. This is because if it is less than 0.5 ppm, it is difficult to obtain a high sterilization rate in a short sterilization treatment time. A more preferable concentration of ozone water is 3 ppm or more, and a more preferable concentration of ozone water is 5 ppm or more. The upper limit of the concentration of ozone water is not particularly limited, and ozone water having a concentration of, for example, about 40 ppm that can be manufactured can be used. However, since the present invention can obtain a high sterilization rate without using such high-concentration ozone water, the concentration is preferably 30 ppm or less, and more preferably 20 ppm or less, considering the production cost of ozone water. .

  The concentration of ozone water can be determined according to the sterilization rate to be obtained. That is, when a high sterilization rate is desired, high-concentration ozone water is used, and when a low sterilization rate is sufficient, low-concentration ozone water may be used. Moreover, the density | concentration of ozone water can be defined with the kind of sterilization target object. In other words, in the case where a sterilization effect that is relatively easy to obtain such as vegetables is to be sterilized, low-concentration ozone water is used, and in the case that the sterilization effect is difficult to obtain such as seeds and bulbs Will use high-concentration ozone water. Furthermore, as will be described later, the concentration of ozone water can be determined according to the time during which the object to be sterilized can be immersed in ozone water.

  In step (b), the time for treating the sterilization object with ozone water, typically dipping in the ozone water (hereinafter, treatment time) is affected by the concentration of the ozone water used. That is, when ozone water having a low concentration is used, it is necessary to lengthen the treatment time, and when using ozone water having a high concentration, the treatment time can be shortened. Moreover, processing time can be defined by the kind of sterilization target object. In other words, the processing time needs to be shortened when an object that is relatively easy to obtain a sterilizing effect is used as the sterilizing target, and the processing time needs to be increased when an object that is difficult to obtain the sterilizing effect is used. For example, in sterilization considering blast disease and seedling blight, it is preferable to immerse for 5 minutes at an ozone water concentration of 0.5 ppm or more, and for idiot seedling disease, it is preferable to immerse for 1 minute or more at 2 ppm or more.

  In the case of the present invention, by providing step (a), the processing time for obtaining a predetermined sterilizing effect can be greatly shortened as compared with the case where the sterilization target is simply immersed in ozone water. A specific example will be described with reference to FIG. FIG. 2 is a graph showing the relationship between the treatment time and the number of adherent bacteria measured under the following conditions. As shown in FIG. 2, the effect of reducing the number of attached bacteria that cannot be obtained by simply immersing in ozone water can be obtained by exposing the sterilization target to an atmosphere that has been previously depressurized. Moreover, it can be understood from FIG. 2 that the sterilization effect can be sufficiently obtained when the treatment (immersion) time is about 5 minutes, and the sterilization effect is almost saturated after the treatment (immersion) time of about 10 minutes.

  Conditions: 50 g of rice seedling blight contaminated pods were placed in a 10 L sterilization tank. The sterilization tank is evacuated to a vacuum degree of 20 torr, and then the elapsed (treatment) time and the number of attached bacteria after supplying 5 L of ozone water with a concentration of 10 ppm to the sterilization tank are measured. It is shown in FIG.

  In the present invention, it is preferable to stir the ozone water while the object to be sterilized is immersed in the ozone water. This is to promote the contact of fresh ozone water with the object to be immersed. Stirring may be performed by using a stirring blade or by forming a water flow by continuously supplying and draining ozone water. Of course, other methods may be used. Further, fresh ozone water can be brought into contact with the sterilization target object by continuously supplying new ozone water without stirring.

  FIG. 3 shows the correlation between the sterilization rate when the soot is exposed to an atmosphere having a degree of vacuum of 20 torr, the sterilization treatment (immersion) time, and the ozone water concentration. In FIG. 3, “D” indicates a sterilization rate of 90%, “2D” indicates a sterilization rate of 99%, and “3D” indicates a sterilization rate of 99.9%. As the bactericidal effect, when the disease incidence is required to be 0.1% or less at the time of raising seedlings, 3D (99.9%) in FIG. It can be seen that the sterilization may be performed within the upper right condition range from the curve.

  FIG. 4 shows the results of conducting a seedling raising test using the rice seedling blight, and examining the disease incidence at that time. The seedling test period is 30 days. The ozone water concentration was 20 ppm, the degree of vacuum before supplying ozone water was 20 torr, and the sterilization treatment (immersion) time was 20 minutes. For comparison, the cases of seed pods without sterilization treatment (FIG. 4, no treatment) and seed pods immersed in ozone water with a concentration of 20 ppm at atmospheric pressure (FIG. 4, ozone water immersion only) were used as comparisons. As a result, as shown in FIG. 4, when 50% of the rice was not sterilized, less than 10% of the rice became sick when immersed in ozone water. On the other hand, it was not possible to confirm the occurrence of disease in the soot seeds exposed to a reduced pressure atmosphere before supplying ozone water. Moreover, germination disorder could not be confirmed.

<Device>
Next, an embodiment of a sterilization apparatus suitable for carrying out the sterilization method according to the present invention will be described with reference to the drawings.
FIG. 5 is a diagram showing a configuration of the sterilizer 100 according to the present embodiment.
As shown in FIG. 5, the sterilization apparatus 100 according to the present embodiment accommodates the seed potato R and sterilizes the sterilization tank 1, and is attached to the upper part of the sterilization tank 1 to open and close the upper end opening of the sterilization tank 1. A charging lid 2 is provided.
A vacuum pump 3 is connected to the sterilization tank 1 via an intake pipe 31, and a valve 4 is disposed on the intake pipe 31. By operating the vacuum pump 3 with the closing lid 2 closed and the valve 4 opened, the sterilization tank 1 can be set to a predetermined degree of vacuum.

  An ozone water storage tank 5 is connected to the sterilization tank 1 via an ozone water supply pipe 9. A valve 10 for controlling the supply of ozone water O from the ozone water storage tank 5 to the sterilization tank 1 is disposed on the ozone water supply pipe 9.

A raw water supply pipe 6 is connected to the ozone water storage tank 5. A raw water supply source (not shown) is connected to the raw water supply pipe 6, and water as a raw material for the ozone water O can be supplied to the ozone water storage tank 5 through the raw water supply pipe 6.
An ozone gas generator 7 is connected to the ozone water storage tank 5. The ozone gas generated by the ozone gas generator 7 is supplied into the raw material water supplied to the ozone water storage tank 5. As a method for generating ozone gas, three kinds of methods are well known: a discharge method, an electrolysis method, and an ultraviolet lamp method. Among these, the discharge method has the lowest production cost. The electrolytic method is used particularly when high concentration ozone gas is generated. The ultraviolet lamp method has an advantage that ozone gas can be easily generated although the ozone concentration is low. The ozone gas generator 7 according to the present embodiment may be any method.

  In the present embodiment, a bubble dissolution method is used as a method for generating ozone water O. That is, the ozone water storage tank 5 is provided with a fine bubble dissolving device 8, and the ozone gas generated by the ozone gas generator 7 is supplied toward the rotor blades 81 of the fine bubble dissolving device 8. The supplied ozone gas is agitated by the rotary blade 81 together with the raw water, so that the ozone gas becomes bubbles and is dissolved in the raw water to generate ozone water O. By adjusting the stirring at this time, it is preferable to make the bubbles of the ozone gas finer to the particle size as described above.

  In addition to the above-described bubble dissolution method, ozone water O is produced from ozone gas by flowing raw material water through a porous tetrafluoroethylene film and flowing ozone gas outside thereof to absorb the ozone gas into the water. A diaphragm dissolution method for generating O can be employed. Moreover, ozone water O can also be produced | generated by the packed bed melt | dissolution method which flows water from the upper part of a packed bed, flows ozone gas from the lower part, and melt | dissolves ozone gas in a gas-liquid countercurrent type within a packed bed.

  The sterilization tank 1 is connected to a discharge pipe 11 for discharging seed potato R and ozone water O, which are sterilization objects, after the sterilization process is completed. On the discharge pipe 11, a valve 12 that controls the discharge of the seed soy R and ozone water O in the sterilization tank 1 to the outside is disposed.

  At the discharge port of the discharge pipe 11, a waste liquid tank 13 in which a recovery bucket 14 is disposed is disposed. The recovery bucket 14 is made of, for example, a mesh and recovers the seed soot R discharged from the discharge pipe 11, but the ozone water O can pass to the waste liquid tank 13. A discharge pipe 15 is connected to the waste liquid tank 13, and the ozone water O discharged to the waste liquid tank 13 is discharged to the outside through the discharge pipe 15. At this stage, ozone in the ozone water O has disappeared, but for convenience of explanation, it is referred to as ozone water O.

Now, a procedure for sterilizing the seed pod using the above sterilizer 100 will be described with reference to FIGS.
As shown in FIG. 6, seed potato R that is an object to be sterilized is accommodated in sterilization tank 1. At this time, the valve 4 on the intake pipe 31 is open, but the valve 10 on the ozone water supply pipe 9 and the valve 12 on the discharge pipe 11 are closed.
The vacuum pump 3 is actuated after the storage of the seed soot R in the sterilization tank 1 is completed. When the inside of the sterilization tank 1 reaches a predetermined degree of vacuum, the operation of the vacuum pump 3 is stopped and the valve 4 is closed. At this time, the inside of the sterilization layer 1 in which the seed candy R which is the sterilization target is accommodated forms a reduced-pressure atmosphere having a predetermined degree of vacuum.

  In addition, after accommodating seed soy R, ozone water O needs to be generated and stored in the ozone water storage tank 5 until the atmosphere inside the sterilization tank 1 reaches a predetermined degree of vacuum. Here, it is necessary to generate ozone water O in consideration of the short half-life of ozone gas. This is because if the ozone water O is stored in the ozone water storage tank 5 for a long time after being generated, the concentration of the ozone water O decreases.

  After the atmosphere inside the sterilization tank 1 reaches a predetermined degree of vacuum, the valve 10 on the ozone water supply pipe 9 is opened. Then, as shown in FIG. 7, the ozone water O in the ozone water storage tank 5 flows into the sterilization tank 1 through the ozone water supply pipe 9. Since the sterilization tank 1 is in a reduced pressure atmosphere having a predetermined degree of vacuum, the ozone water O easily flows into the sterilization tank 1 without using a supply means. When a predetermined amount of ozone water O flows into the sterilization tank 1, the valve 10 on the ozone water supply pipe 9 is closed. This completes the supply of the ozone water O to the sterilization tank 1. After that, for example, the valve 4 may be opened to open the inside of the sterilization tank 1 to the atmosphere. However, it is preferable to maintain a reduced pressure state until the sterilization treatment is completed in order to obtain a high sterilization rate.

  Thereafter, the seed pod R is sterilized by maintaining the state in which the seed pod R is immersed in the ozone water O for a predetermined time. In the present embodiment, the seed soot R is exposed to a reduced pressure atmosphere, and ozone water O is supplied to the seed soot R in this state. Therefore, since the ozone water O can sufficiently enter not only the surface of the seed pod R but also between the skin and the skin of the seed pod R, the sterilizing effect can be improved.

  When the valve 12 on the discharge pipe 11 is opened after the sterilization process is performed for a predetermined time, the sterilized seed soy R and ozone water O are discharged from the sterilization tank 1 through the discharge pipe 11 as shown in FIG. To be discharged. The seed soak R is collected in the collection bucket 14. Further, the ozone water O flows through the waste liquid tank 13 to the discharge pipe 15. The seed pod R collected in the collection bucket 14 is then planted after a predetermined treatment such as drying.

It is a graph which shows the relationship between a vacuum degree (torr) and a viable cell rate (-). It is a graph which shows the relationship between processing time and the number of adherent bacteria. It is a graph which shows the correlation of ozone water density | concentration and processing time about the sterilization rate in case the degree of vacuum is 20 torr. It is a graph which shows the breeding result of the seed potato which applied this invention etc. It is a figure which shows the system configuration | structure of the sterilizer by this Embodiment. It is a figure which shows the system configuration | structure of the sterilizer by this Embodiment, Comprising: It is a figure which shows the state which has exposed the sterilization target object (seed seed) in a vacuum atmosphere. It is a figure which shows the system configuration | structure of the sterilization apparatus by this Embodiment, Comprising: It is a figure which shows the state which has immersed the sterilization target object (seed seeds) in ozone water. It is a figure which shows the system configuration | structure of the sterilizer by this Embodiment, Comprising: It is a figure which shows the state which the sterilization process complete | finished and collect | recovers the sterilization target object (seed meal).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sterilization tank, 2 ... Input lid, 3 ... Vacuum pump, 4, 10, 12 ... Valve, 5 ... Ozone water storage tank, 6 ... Raw material water supply piping, 7 ... Ozone gas generator, 8 ... Fine bubble dissolution apparatus, DESCRIPTION OF SYMBOLS 9 ... Ozone water supply piping, 11, 15 ... Discharge piping, 13 ... Waste liquid tank, 14 ... Collection bucket, R ... Seed rice, O ... Ozone water, 100 ... Sterilizer

Claims (10)

Step (a) of depressurizing the atmosphere containing the sterilization object;
Supplying ozone to the object to be sterilized contained in the decompressed atmosphere (b);
A method for sterilizing agricultural products, comprising:   The method for sterilizing agricultural products according to claim 1, wherein the object to be sterilized is seeds or bulbs.   The method for sterilizing agricultural products according to claim 1 or 2, wherein, in the step (a), the atmosphere in which the object to be sterilized is stored has a vacuum level of 100 torr or less.   The method for sterilizing agricultural products according to any one of claims 1 to 3, wherein, in the step (a), the atmosphere in which the sterilization object is accommodated is set to a vacuum degree of 50 torr or less.   In the said step (b), ozone water whose ozone concentration is 0.5-40 ppm is supplied as said ozone, The sterilization method of the crops in any one of Claims 1-4 characterized by the above-mentioned.   6. The method according to claim 5, wherein in the step (b), the bubble diameter of ozone gas in the ozone water is 50 μm or less.   The method for sterilizing agricultural products according to claim 6, wherein, in the step (b), the sterilization object is immersed in the ozone water for 1 minute or more. A processing container having a storage space for a sterilization target and in which the sterilization processing of the sterilization target is performed in the storage space;
A depressurization part that makes the housing space a depressurized atmosphere;
An ozone water supply unit for supplying ozone water into the processing vessel;
A crop sterilizing apparatus comprising: After the inside of the accommodation space is in a predetermined decompression state by the decompression unit,
The agricultural product sterilization apparatus according to claim 8, wherein the ozone water is supplied into the processing container by the ozone water supply unit.   The agricultural product sterilization apparatus according to claim 8 or 9, wherein the ozone water supply unit includes a bubble refining unit that refines bubbles of ozone gas.

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