Low oxygen concentration insecticidal method and device used therefor

Abstract

To provide a low-oxygen-concentration insecticidal method and an insecticidal device, which enable insecticidal and ovicidal treatments for a plant or a crude drug in a large amount of 10 kg or more to be provided in a short period of time while maintaining the quality of the plant or the crude drug.SOLUTION: An insecticidal method includes: a low-oxygen-concentration gas substitution step of setting oxygen concentration to be 3% or less by substituting inert gas for atmospheric air in a sealed space in which an object substance, that is, a plant or a crude drug in an amount of 10 kg or more is stored; a gas temperature control step of controlling the temperature of low-oxygen-concentration gas; and a substance temperature control step of setting the temperature of the object substance to be 30°C or more. An apparatus is used for the insecticidal method.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for killing insects by low oxygen concentration in plants or herbal medicines and an apparatus used therefor. [Background technology]

[0002] The low-oxygen insecticide method, which does not use chemicals, is known as an alternative to methyl bromide and aluminum phosphide fumigation. The low-oxygen insecticide method kills not only adult insects but also larvae and eggs by subjecting the target insects, such as herbal medicines, to a low-oxygen environment for a certain period of time.

[0003] Regarding the low-oxygen concentration insecticidal method, Non-Patent Document 1 describes that when dried specimens infested with the pests tobacco beetles and rice weevils were placed in a space maintained at 30°C with an oxygen concentration of less than 0.1% for three weeks, there was no re-emergence of the pests even approximately three months after treatment.

[0004] Non-patent document 2 describes that when approximately 3 g of infested brown rice containing eggs, larvae, and pupae of the pest rice weevil was placed in a small, sealed, oxygen-free environment using an oxygen absorber at 30°C for three months, the number of adults who emerged was zero.

[0005] Non-Patent Document 3 describes how a small container containing 20 eggs each of the tobacco beetle, the red flour beetle, and the Indian meal moth in 1 g of whole wheat flour, or a small container containing 1 g of brown rice in which rice weevils had been allowed to lay eggs for two days in advance (500 adult weevils / 100 g of brown rice), was placed in an acrylic cylindrical container and sealed, and the inside of the container was replaced with nitrogen gas to make the oxygen concentration 0.1% and the relative humidity inside the container adjusted to 70% or higher, and then the container was placed in a room at 30°C. The containers were placed in the containers and exposed for 2, 4, 7, 10, or 14 days in each test area, and then opened. The egg-killing effect was evaluated by the number of hatched larvae for the three species other than the rice weevil, and by the number of adult insects that emerged for the rice weevil. Of the four species used in the test, the species that showed the strongest resistance to hypoxia was the tobacco beetle, which required 14 days of treatment to kill 100% of its eggs, while 7 days was necessary for the rice weevil, and 2 days for the red flour beetle and Indian meal moth.

[0006] Non-Patent Document 4, by the same group as Non-Patent Document 3, discloses almost the same content as Non-Patent Document 3.

[0007] Patent Document 1 describes a method and device for suffocating pests that parasitize materials such as cultural properties by repeating vacuum treatment and nitrogen injection.

[0008] As described in Non-Patent Documents 1 and 2, the temperature of the atmosphere has been maintained at 30°C during low-oxygen concentration insecticidal treatment, but there have been no reports focusing on the temperature of the treated object. Furthermore, there have been no reports of low-oxygen concentration insecticidal methods applied to the treatment of plants or herbal medicines weighing 10 kg or more. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 2017-127294 [Non-patent literature]

[0010] [Non-Patent Document 1] Kikawa Rika et al.; Prototype of a device for treating cultural property insects using inert gases such as nitrogen and examples of treatment; Conservation Science, No. 38, pp. 1-8 (1999) [Non-patent document 2] Yuko Onodera et al.; [Report] Low oxygen concentration insecticidal method - Examination of treatment periods at 25℃, 27.5℃, and 30℃ -; Conservation Science, No. 54, pp. 161-170 (2015) [Non-patent document 3] Miyanoshita Akihiro et al.; Effect of CA treatment on stored food pests; Abstracts of the 41st Annual Meeting of the Society of Urban Pest Management, p. 9 [Non-patent document 4] Kitazawa, Hiroaki et al.: Egg killing treatment of stored herbal medicine pests using CA treatment; Proceedings of the 29th Annual Meeting of the Japan Society of Packaging Science, pp. 52-53 (Presentation number e-06) Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention aims to provide a low-oxygen concentration insecticidal method and insecticidal device that can kill insects and eggs in large quantities of plants or herbal medicines weighing 10 kg or more in a short period of time while maintaining the quality of the plants or herbal medicines. [Means for solving the problem]

[0012] The gist of the present invention is as follows. (1) A process of replacing the atmosphere in a sealed space where 10 kg or more of the target substance, which is a plant or herbal medicine, is stored with an inert gas to reduce the oxygen concentration to 3% or less, thereby replacing the atmosphere with a low-oxygen gas; a gas temperature adjusting step of adjusting the temperature of the low oxygen concentration gas; a substance temperature adjusting step of adjusting the temperature of the target substance to 30°C or higher; An insecticidal method comprising: (2) The insecticidal method according to (1), wherein the temperature of the low-oxygen concentration gas is adjusted to 35 to 40°C in the gas temperature adjusting step. (3) In the substance temperature adjustment step, the low-oxygen concentration gas around the target substance is collected by an air collection and supply mechanism that uniformly supplies the low-oxygen concentration gas to the target substance, thereby raising the temperature of the target substance to 30°C or higher. (4) In the substance temperature adjustment step, an exhaust mechanism is used to actively exhaust air around the target substance, thereby uniformly supplying the low-oxygen concentration gas to the target substance, thereby setting the temperature of the target substance to 30°C or higher. (5) The insecticidal method according to (3) or (4), wherein the air collection and supply mechanism or the exhaust mechanism uses a supply nozzle that is inserted into the target substance and supplies the low-oxygen concentration gas to the target substance at a desired pressure. (6) The insecticidal method described in (5) above, wherein the supply nozzle has a ventilation section through which the low-oxygen concentration gas is supplied to the target substance, and the ventilation section uses holes or mesh that are large enough to prevent the target substance from entering. (7) The insecticidal method according to (6), wherein the ventilation part is installed near the tip of the supply nozzle. (8) The insecticidal method according to any one of (1) to (7), wherein the low-oxygen concentration gas is heated by a blower equipped with a heating means and is blown onto the target substance. (9) The insecticidal method according to any one of (1) to (8), wherein the target substance is heated by a device equipped with a heating means. (10) An insecticidal method according to any one of (1) to (9), further comprising an oxygen concentration measurement step of measuring the oxygen concentration of the target substance or the area around the target substance, wherein the replacement step adjusts the supply amount of the low-oxygen concentration gas based on the oxygen concentration of the target substance or the area around the target substance. (11) A temperature measurement step of measuring the temperature of the target substance or the surrounding area of the target substance; The insecticidal method according to any one of (1) to (10), wherein the gas temperature adjusting step adjusts the temperature of the low-oxygen concentration gas based on the temperature of the target substance or the temperature around the target substance. (12) The insecticidal method according to (10) or (11), wherein the replacement step adjusts the supply time of the inert gas based on the oxygen concentration measurement step. (13) The insecticidal method according to (11) or (12), wherein the gas temperature adjusting step adjusts the temperature of the low-oxygen concentration gas by the temperature measuring step. (14) The insecticidal method according to any one of (11) to (13), wherein the substance temperature adjusting step adjusts the process time by the temperature measuring step. (15) The insecticidal method according to any one of (1) to (14), wherein the substitution step comprises flowing the inert gas into the sealed space so that the sealed space has a positive pressure compared to the pressure outside the sealed space. (16) The insecticidal method according to any one of (1) to (15), wherein the substitution step actively introduces the inert gas into the sealed space and actively discharges the low-oxygen-concentration gas. (17) The replacing step includes providing a first sealed space in the sealed space and a second sealed space inside the first sealed space, and storing the target substance in the second sealed space; The inert gas is introduced into the second sealed space, The insecticidal method according to any one of (1) to (16), wherein the oxygen concentration of the low-oxygen gas in the second sealed space is maintained lower than the oxygen concentration in the first sealed space. (18) The insecticidal method according to (17), wherein the replacement step comprises flowing in the inert gas so that the pressure in the second sealed space becomes positive compared to the pressure in the first sealed space. (19) The insecticidal method according to any one of (1) to (18), wherein the substitution step includes an oxygen adsorption step of adsorbing oxygen in the sealed space. (20) The insecticidal method according to any one of (1) to (19), wherein the substance temperature adjustment step continues for 3 days to 3 weeks.

[0013] (21)(a) a processing chamber having an enclosed space; (b) an oxygen concentration adjusting means for replacing the atmosphere in the sealed space with an inert gas to reduce the oxygen concentration to 3% or less; (c) a gas temperature adjusting means for adjusting the temperature of the gas in the sealed space; (d) a gas-permeable target substance storage container provided in the treatment chamber and capable of storing 10 kg or more of the target substance, which is a plant or herbal medicine; (e)(i) an air collection and supply mechanism that collects low-oxygen concentration gas around the target substance and uniformly supplies the low-oxygen concentration gas to the target substance; (ii) an exhaust mechanism that actively exhausts the air around the target substance, thereby uniformly supplying the low-oxygen concentration gas to the target substance; (iii) a blower equipped with a heating means for heating the low-oxygen concentration gas and applying it to the target substance; and (iv) An apparatus equipped with a heating means for heating the target substance. and at least one means selected from An insecticidal device having (22) The insect killing device according to (21), wherein the air collection and supply mechanism has a supply nozzle that is inserted into the target substance and supplies the low-oxygen concentration gas to the target substance at a desired pressure. (23) The insecticidal device according to (22), wherein the supply nozzle has a vent for supplying the low-oxygen concentration gas to the target substance, and the vent uses holes or a mesh that is large enough to prevent the target substance from entering. (24) The insecticidal device according to (23), wherein the ventilation part is installed near the tip of the supply nozzle. (25) The insect killing device according to any one of (21) to (24) above, further comprising an oxygen concentration measuring means for measuring the oxygen concentration in the target substance or in the vicinity of the target substance. (26) The insect killing device according to any one of (21) to (25) above, further comprising a temperature measuring means for measuring the temperature of the target substance or the surroundings of the target substance. (27) The insect killing device according to (25) or (26), wherein the oxygen concentration adjusting means has a means for adjusting the replacement time of the inert gas by the oxygen concentration measuring means. (28) The insect killing device according to (26) or (27), wherein the gas temperature adjusting means has a means for adjusting the temperature of the low-oxygen concentration gas by the temperature measuring means. (29) The insecticidal device according to any one of (21) to (28), wherein the oxygen concentration adjusting means has a means for introducing the inert gas so that the sealed space has a positive pressure compared to the outside of the sealed space. (30) An insecticidal device according to any one of (21) to (29), wherein the oxygen concentration adjusting means has a means for actively injecting the inert gas into the sealed space and discharging the low oxygen concentration gas. (31) The oxygen concentration adjusting means provides a first sealed space and a second sealed space inside the first sealed space in the sealed space, and stores the target substance in the second sealed space; The inert gas is introduced into the second sealed space, The insect killing device according to any one of (21) to (30), further comprising a means for maintaining the oxygen concentration of the low-oxygen concentration gas in the second sealed space lower than the oxygen concentration in the first sealed space. (32) The insecticidal device according to (31), wherein the oxygen concentration adjusting means has a means for introducing the inert gas so that the pressure in the second sealed space becomes positive compared to the pressure in the first sealed space. (33) The insect killing device according to any one of (21) to (32), wherein the oxygen concentration adjusting means has a means for adsorbing oxygen in the sealed space. (34) The insecticidal device according to any one of (21) to (33) above, which has a means for maintaining the temperature of the target substance at 30° C. or higher for 3 days to 3 weeks. [Effects of the Invention]

[0014] According to the present invention, insects and eggs can be killed in a large amount of plants or herbal medicines, weighing 10 kg or more, in a short period of time while maintaining the quality of the plants or herbal medicines. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 shows the state when the ventilation part of a supply nozzle located at the tip of an air collection and supply mechanism that collects low-oxygen concentration gas around a target substance and supplies the low-oxygen concentration gas uniformly to the target substance is inserted into the target substance and the low-oxygen concentration gas is supplied to the target substance. [Figure 2]FIG. 2 shows the state when the ventilation part of the supply nozzle located at the tip of the exhaust mechanism, which actively exhausts the area around the target substance to uniformly supply the low-oxygen concentration gas to the target substance, is inserted into the target substance and the low-oxygen concentration gas is supplied to the target substance. [Figure 3] FIG. 3 is a diagram showing a specific mechanism of the supply nozzle. [Figure 4] Figure 4 shows the state in which a heating means for heating the target substance is inserted into the target substance, the target substance is heated to adjust the temperature, and the oxygen concentration is adjusted by allowing low-oxygen concentration gas to enter through the wall or upper opening of the target substance storage container. [Figure 5] FIG. 5 shows the results of the essential oil content measurement test. [Figure 6] FIG. 6 is a diagram showing the results of the sensory evaluation of dried daikon radish. [Figure 7] FIG. 7 shows the results of a sensory test of dried green onions. [Figure 8] FIG. 8 shows the test results of Example 6. [Figure 9] FIG. 9 shows the test results of Example 7. [Figure 10] FIG. 10 shows the test results of Example 8. DETAILED DESCRIPTION OF THE INVENTION

[0016] The target substances of the present invention are not particularly limited as long as they are plants or herbal medicines that are damaged by pests, and examples include agricultural products and foods, specifically grains such as rice, wheat, and corn, beans such as soybeans and adzuki beans, fruit trees such as chestnuts, potatoes such as cassava and sweet potatoes, dried foods such as shiitake mushrooms and bonito flakes, flowers such as chrysanthemums, orchids, and komatsuna, vegetables, fibers such as silk and cotton, spices such as pepper and clove, medicinal plants such as herbal medicines, wood such as imported wood, processed products of these (for example, rice flour, wheat flour, cassava flour, sweets, biscuits, macaroni, powdered drinks, paper bags, etc.), and seeds of the above-mentioned grains and beans.

[0017] The pests that are the target of the present invention vary depending on the type of plant or herbal medicine that is the target substance, and are not particularly limited, but examples include rice weevils, red flour beetles, pyralids (e.g., Indian meal moth), cigarette beetles, bookworms, chestnut weevils, as well as mites, flies, wasps, ants, and termites.

[0018] The insecticidal method of the present invention includes a step of placing 10 kg or more, preferably 2000 kg or less, more preferably 80 to 1000 kg of a target substance, which is a plant or herbal medicine in which or which may be infested with harmful insects (eggs, larvae, pupae, adults) or pests such as mites, in a target substance storage container such as a flexible container bag, tray, polypropylene bag, polyethylene bag, bale, or gunny bag, and replacing the atmosphere in the sealed space with an inert gas (e.g., nitrogen gas, argon gas) in a treatment cabinet (e.g., a herbal medicine storage cabinet) to reduce the oxygen concentration to 3% or less, thereby replacing the atmosphere in the sealed space with a low-oxygen concentration gas; a gas temperature adjusting step of adjusting the temperature of the low oxygen concentration gas; a substance temperature adjusting step of adjusting the temperature of the target substance to 30°C or higher; Includes.

[0019] The target substance storage container used in the present invention is preferably breathable. This is because it prevents moisture buildup in the herbal medicine, which could lead to quality deterioration. Furthermore, when non-low oxygen concentration gas is exhausted from within the target substance storage container in the present invention, the low oxygen concentration gas can easily pass through the walls of the target substance storage container from outside the target substance storage container and reach the target substance. Furthermore, when low oxygen concentration gas is supplied into the target substance storage container, the non-low oxygen concentration gas present within the target substance storage container can easily pass through the walls of the target substance storage container and be exhausted to the outside of the target substance storage container. Here, "breathable" refers to the movement of gas between the inside and outside of the target substance storage container through the walls of the target substance storage container. Preferred materials for the target substance storage container include polypropylene, polyethylene, linen, cotton, and paper. Furthermore, even if the material of the target substance storage container itself is not breathable, it is not limited to these as long as it is made breathable by processing it with a weave or holes. On the other hand, if the target substance storage container has no or low breathability, the temperature and humidity around the target substance can be adjusted in the substance temperature adjustment process of the present invention by forcibly supplying or exhausting low-oxygen concentration gas into the substance storage container.

[0020] 1 to 4 each show one embodiment of the present invention, and the present invention will be explained using these. In the process of replacing the atmosphere with a low oxygen concentration gas, a valve located between the oxygen concentration adjusting unit 6 and the processing chamber 1 is opened, and an inert gas (such as nitrogen gas) is pressure-injected from the oxygen concentration adjusting unit 6 into the processing chamber 1.

[0021] In order to achieve the insecticidal and egg-killing effects of the present invention, the oxygen concentration in the treatment chamber 1 must be kept below 3%, usually below 2%, preferably below 1%, more preferably below 0.6%, and even more preferably below 0.1%. In the gas temperature adjusting step, the temperature of the ambient gas (nitrogen gas, etc.) is adjusted by the gas temperature adjusting unit 7. The gas temperature adjusting unit 7 is, for example, a boiler.

[0022] The temperature of the low oxygen concentration atmospheric gas can be changed appropriately depending on the temperature of the target substance 8, but is usually 30°C or higher, preferably 35 to 40°C. In the substance temperature adjusting step, the temperature of the target substance 8 is adjusted to 30°C or higher, preferably 30 to 40°C.

[0023] Simply maintaining the temperature of low-oxygen-concentration atmospheric gas at 30°C, as has been done conventionally, makes it difficult to raise the temperature of the entire target substance, weighing 10 kg or more, to 30°C or higher, and it is difficult to achieve sufficient insecticidal and egg-killing effects in a short period of time.

[0024] There are no particular limitations on the means for raising the temperature of the target substance to 30°C or higher. For example, (1) In the gas temperature adjusting step, the temperature of the low oxygen concentration gas is adjusted to 35 to 40°C. (2) In the substance temperature adjustment step, the low-oxygen concentration gas around the target substance is collected, and a gas collection and supply mechanism is used to uniformly supply the low-oxygen concentration gas to the target substance, thereby adjusting the temperature of the target substance to 30°C or higher. (3) In the substance temperature adjustment step, an exhaust mechanism is used to actively exhaust the air around the target substance, thereby uniformly supplying the low-oxygen concentration gas to the target substance, and the temperature of the target substance is set to 30°C or higher. (4) applying the heated low-oxygen concentration gas to the target substance using a blower equipped with a heating means; (5) Heating the target substance using a device equipped with a heating means; These methods can be combined as needed.

[0025] Embodiments of the means (2) are shown in Figures 1 and 3. The gas collection and supply mechanism 3 uses a supply nozzle 4 that is inserted into the target substance 8 and supplies the low-oxygen concentration gas to the target substance 8 at a desired pressure. An embodiment of the supply nozzle 4 is shown in Figure 3. The supply nozzle 4 has a vent 42 through which the low-oxygen concentration gas is supplied to the target substance 8, and the vent 42 preferably uses holes or a mesh that is large enough to prevent the target substance 8 from entering. The vent is preferably installed near the tip of the supply nozzle, and preferably at the bottom of the target substance storage container 2.

[0026] 2 and 3 show an embodiment of the means (3). For example, an exhaust fan is used as the exhaust mechanism 9, and the ventilation part of the supply nozzle 4 located at the tip of the exhaust mechanism 9 is inserted into the target substance 8, and the low oxygen concentration gas is supplied to the target substance 8. In the means (3) as well, it is preferable that the ventilation part 42 uses holes or a mesh that is large enough to prevent the target substance 8 from entering, and it is preferable that the ventilation part 42 be installed near the tip of the supply nozzle 4.

[0027] If a blower / exhaust fan having both a blowing function and an exhausting function is used, the same device can be used for the air collection / supply mechanism 3 of the means (2) and the exhaust mechanism 9 of the means (3), and can be switched appropriately.

[0028] In the above-mentioned means (4), examples of the blower equipped with a heating means include a dryer (blower), a sirocco fan, and a duct fan. In a blower that can blow air while pressurizing it, such as a dryer, the temperature of the gas being blown can be adjusted by adjusting the airflow rate and the size of the air outlet.

[0029] An embodiment of the means (5) is shown in Figure 4. Examples of devices equipped with heating means 10 include a sheathed tube heater, a heat pipe, and a Peltier element, which can be inserted into the target substance 8 for use.

[0030] In the above-mentioned means (1) to (5), by using a device capable of stirring the target substance, it is possible to bring the target substance to the desired temperature in a short time. Furthermore, when a device capable of stirring is used, it is possible to supply a low-oxygen concentration gas to the target substance 8 by utilizing the breathability of the target substance storage container 2, without having an active gas adjustment mechanism such as the gas collection and supply mechanism 3, exhaust mechanism 9, or supply nozzle 4 shown in Figures 1 and 2.

[0031] In the above means (1) to (5), by having a control unit 5 that detects the oxygen concentration, gas temperature, or target substance temperature inside the treatment chamber 1 or target substance storage container 2 and controls the oxygen concentration regulator 6, gas temperature regulator 7, air collection and supply mechanism 3, blower equipped with heating means, and heating means 10, it is possible to more efficiently supply low-oxygen concentration gas to the target substance storage container 2. When the temperature of the target substance 8 becomes high, for example, low-oxygen concentration gas of 30°C or less can be supplied to bring the target substance to the desired temperature. In the above means (3), since the temperature inside the target substance storage container 2 is similar to the temperature of the exhaust air, a temperature sensor may be provided in the supply nozzle 4.

[0032] There are no particular restrictions on the means of reducing the oxygen concentration in the enclosed space where the target substance is stored to 3% or less. For example, (1) Injecting the inert gas into the sealed space so that the pressure therein is positive compared to the pressure outside the sealed space; (2) Injecting the inert gas into the sealed space and discharging the low-oxygen-concentration gas actively. (3) A first sealed space and a second sealed space are provided inside the first sealed space, the target substance is stored in the second sealed space, the inert gas is introduced into the second sealed space, and the oxygen concentration of the low-oxygen concentration gas in the second sealed space is maintained lower than the oxygen concentration in the first sealed space. (4) The inert gas is introduced so that the pressure in the second sealed space becomes positive compared to the pressure in the first sealed space. (5) providing an oxygen adsorption step for adsorbing oxygen in the sealed space; These methods can be combined as needed.

[0033] An embodiment of the means (1) will be described with reference to Figure 1. A valve located between the oxygen concentration adjusting unit 6 and the processing chamber 1 is opened, and an inert gas (nitrogen gas, etc.) is pressurized into the processing chamber 1 from the oxygen concentration adjusting unit 6. The control unit 5 adjusts the inflow of the inert gas from the oxygen concentration adjusting unit 6 so that the pressure inside the processing chamber 1 is positive compared to the pressure outside the processing chamber 1. This prevents gas with a high oxygen concentration from flowing into the processing chamber 1 from outside the processing chamber 1, and makes it possible to maintain a low oxygen concentration inside the processing chamber 1.

[0034] An embodiment of the means (2) will be described with reference to Figure 1. A valve located between the oxygen concentration adjusting unit 6 and the processing chamber 1 is opened, and an inert gas (nitrogen gas, etc.) is pressure-fed into the processing chamber 1 from the oxygen concentration adjusting unit 6. The control unit 5 actively causes the gas to flow into the processing chamber 1, and an exhaust mechanism (not shown) is further provided in the processing chamber 1, which actively exhausts the gas inside the processing chamber 1. As a result, if gas with a high oxygen concentration flows into the processing chamber 1 from outside the processing chamber 1, the oxygen concentration inside the processing chamber 1 will increase, but by forcibly excluding the gas inside the processing chamber 1 and allowing the inert gas to flow in, the oxygen concentration inside the processing chamber 1 can be maintained at a low oxygen concentration.

[0035] An embodiment of the means (3) will be described with reference to FIG. 1. A second processing chamber (not shown) is provided inside processing chamber 1. An inert gas (such as nitrogen gas) is pressurized into processing chamber 1 from oxygen concentration adjusting unit 6. The oxygen concentration inside processing chamber 1 is kept lower than that outside processing chamber 1, and the oxygen concentration inside the second processing chamber (the second sealed space) is kept lower than the oxygen concentration between processing chamber 1 and the second processing chamber (the first sealed space). As a result, thanks to the space between processing chamber 1 and the second processing chamber (the first sealed space), the second processing chamber is more effectively prevented from inflowing gas outside processing chamber 1, and the oxygen concentration inside the second processing chamber (the second sealed space) can be kept more constant. This makes it possible to reduce the flow rate of inert gas flowing into the second processing chamber (the second sealed space).

[0036] An embodiment of the means (4) will be described with reference to FIG. 1. The basic means are the same as those of the means (3). Furthermore, the pressure inside the processing chamber 1 is maintained at a positive pressure compared to the pressure outside the processing chamber 1, and the pressure inside the second processing chamber (the second sealed space) is maintained at a positive pressure compared to the pressure between the processing chamber 1 and the second processing chamber (the first sealed space). As a result, thanks to the space between the processing chamber 1 and the second processing chamber (the first sealed space), the second processing chamber is more effectively prevented from the inflow of gas outside the processing chamber 1, and the oxygen concentration inside the second processing chamber (the second sealed space) can be maintained more constant. This makes it possible to reduce the flow rate of inert gas flowing into the second processing chamber (the second sealed space).

[0037] An embodiment of the means (5) will be described with reference to FIG. 1. The treatment chamber 1 has an oxygen adsorption unit (not shown). The oxygen adsorption unit adsorbs oxygen inside the treatment chamber 1. The oxygen adsorption unit may be, for example, an oxygen scavenger such as Ageless, activated carbon, or pyrogallol, but is not limited to these. This allows the oxygen concentration inside the treatment chamber 1 to be maintained at a low oxygen concentration. This makes it possible to reduce the flow rate of inert gas flowing into the second treatment chamber (the second sealed space).

[0038] The substance temperature adjustment step is continued for usually 2 to 28 days, preferably 3 to 3 weeks, and more preferably 3 to 17 days. [Example]

[0039] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

[0040] Example 1 Tests were conducted to examine the effects of temperature change, oxygen concentration change, and treatment period on the insecticidal effect. (treated insects) The targets were maize weevils (adults), tobacco beetles (adults), red flour beetles (adults), book crickets (adults), and Indian meal moths (larvae). The Dictionary of Cultural Property Pests (National Institute for Cultural Properties and Handbook of Insect Control and Fumigation for Imported Agricultural Products (Science Forum)), Illustrated Guide to Stored Food Pests (National Rural Education Association), and Illustrated Guide to Stored Grain Pests and Natural Enemies (NARO website) state the following about these pests: Maize weevils lay eggs by drilling holes in the grain with their proboscis and then inserting them into the grain. The hatched larvae grow inside the grain and become pupae. The pupae then emerge as adults, and the brown adult beetles break through the seed coat and escape. The Japanese flour beetle feeds on dried plant and animal matter, laying eggs on the surface and the hatched larvae boring into the food to pupate. They then grow into adults and escape by boring holes out of the food. Due to the deep boring characteristics of the tobacco beetle and maize weevil, it is expected that they will be difficult to eradicate. The red flour beetle feeds on grain flour and is often observed on the floors of feed factories and flour mills, and is often found mixed into grain flour and processed products, but it can also infest medicinal herbs, spices, and animal specimens.

[0041] The bookworm damages a wide range of food including bonito flakes, dried noodles, cheese, biscuits, and grain flour, and is commonly found in homes, food factories, and even pharmaceutical factories. It attacks not only stored foods such as grain flour, but also animal and plant specimens. It feeds on mold that grows on book glue and food, and prefers humid environments. It reproduces parthenogenetically, and cases of mass reproduction have been reported.

[0042] The Indian meal moth (Plodia interpunctella) is a stored food pest that attacks many foods, including brown rice, dried fruit, and spices, and is known to be a common insect contaminant (Williams, 1964 Ann. Appl. Biol., 53, 459-475; Maillis, 1997, Handbook of Pest Control). Its strong mandibles allow it to penetrate containers and packaging materials, allowing it to penetrate into packaging. Larvae, in particular, are known to feed on embryos from the outside, potentially damaging grains and herbal medicine seeds. Furthermore, Miyanoshita et al. (51st Annual Meeting of the Japanese Society of Applied Entomology and Zoology, 2007) reported that Plodia interpunctella larvae bore holes in herbal medicines, such as peach blossom root and daisy root, and emerge as adults, suggesting that extermination of this insect is expected to be difficult.

[0043] (Processing conditions) The insect mortality rate was calculated for each period under the following conditions: (1) oxygen concentration of 3.0% or less, temperature of 30°C, (2) oxygen concentration of 0.6% or less, temperature of 30°C, (3) oxygen concentration of 0.3% or less, temperature of 30°C, and (4) oxygen concentration of 0.1% or less, temperature of 30°C. In all conditions, the humidity was kept at 70% to ensure that humidity would not affect the insect mortality rate. (Test procedure) Each insect was reared in a temperature-controlled room, and at the same developmental stage, 20 insects were divided into four replicates of rearing cases containing food, which were then placed in a hypoxic chamber. Therefore, the total number of insects in each test was 80. The rearing cases were enclosed with food preferred by each test insect. A vial containing 10 mL of distilled water was placed inside the hypoxic chamber to maintain humidity. The hypoxic chamber was filled with nitrogen gas or a mixture of nitrogen and oxygen gases, and sealed after adjusting to the desired oxygen concentration. The sealed hypoxic chamber was then placed in a temperature-controlled room set to the temperature required for the test. (death determination) Under each treatment condition, individuals that were not walking one day after treatment were considered dead. (Calculation of insecticidal rate) This was calculated as the number of dead individuals divided by 80 x 100.

[0044] (Test results) Table 1 shows the results of the insecticidal rate under the conditions of (1) an oxygen concentration of 3.0% or less and a temperature of 30°C. The insecticidal rate reached 100% on the 5th day for the rice weevil and Indian meal moth, and on the 17th day for the red flour beetle. A sufficient insecticidal effect was observed after treatment for 5 to 17 days.

[0045] [Table 1]

[0046] Table 2 shows the results of the insecticidal rate under the conditions of (2) an oxygen concentration of 0.6% or less and a temperature of 30°C. The insecticidal rate reached 100% on the second day for the red flour beetle and the bookworm, on the fourth day for the maize weevil, and on the tenth day for the cigarette beetle. Therefore, 100% insecticidal rate was achieved within 2 to 10 days, demonstrating sufficient insecticidal effect.

[0047] [Table 2]

[0048] Table 3 shows the results of the insecticidal rate under the conditions of (3) oxygen concentration of 0.3% or less and temperature of 30°C. Table 4 shows the results of the insecticidal rate under the conditions of (4) oxygen concentration of 0.1% or less and temperature of 30°C. The insecticidal rate for rice weevils and cigarette beetles was 100% on the third day. Therefore, 100% insecticidal rate was achieved in three days, demonstrating sufficient insecticidal effect.

[0049] [Table 3]

[0050] [Table 4]

[0051] It was found that under the same temperature conditions, the lower the oxygen concentration, the higher the insecticidal effect, under treatment conditions (1) to (4). The oxygen concentration must be 3.0% or less, and taking into account the accuracy of adjusting the oxygen concentration, it is usually 2% or less, preferably 1% or less, more preferably 0.6% or less, and even more preferably 0.1% or less.

[0052] Example 2 Tests were conducted to examine the effects of temperature change, oxygen concentration change, and treatment period on the ovicidal effect. (treated insects) The targets were rice weevils (eggs), cigarette beetles (eggs), red flour beetles (eggs), and Indian meal moths (eggs). (Processing conditions) The egg killing rate was calculated for each period under the following conditions: (1) oxygen concentration of 3.0% or less, temperature of 30°C; (2) oxygen concentration of 0.6% or less, temperature of 30°C; (3) oxygen concentration of 0.3% or less, temperature of 30°C; and (4) oxygen concentration of 0.1% or less, temperature of 30°C. The egg killing rate was calculated using the number of adult hatched insects in the untreated area (oxygen concentration 21.0%, temperature 30°C) as the parameter. In all conditions, humidity was kept at 70% to ensure that humidity would not affect the egg killing rate.

[0053] (Test procedure) The number of eggs used in each test for the tobacco beetle, red flour beetle, and Indian meal moth was 80. Since maize weevils lay their eggs inside brown rice, the number of eggs was adjusted as follows: 500 adult maize weevils were reared per 100g of brown rice for three days to allow them to lay eggs in the brown rice, and 8g of this brown rice on which eggs were laid was used for each test. It has been empirically proven that with this rearing method, approximately 80 adult weevils are observed to hatch per 8g of brown rice. The eggs and the brown rice on which they were laid were stored in a hypoxic chamber. A vial containing 10 mL of distilled water was placed inside the chamber to maintain humidity. The chamber was filled with nitrogen gas or a mixture of nitrogen and oxygen gas, and the chamber was sealed after achieving the desired oxygen concentration. The sealed hypoxic chamber was then placed in a temperature-controlled room set to the temperature required for the test. (Survival judgment) After treatment under each treatment condition, the eggs were left at the optimum temperature for hatching with an oxygen concentration of 21.0%, and the hatched individuals were considered survivors. (Calculation of egg killing rate) The calculation was made as follows: (1 - number of larvae hatched in the treated area / number of larvae hatched in the untreated area) x 100.

[0054] (Test results) Table 5 shows the results of the egg killing rate under the conditions of (1) an oxygen concentration of 3.0% or less and a temperature of 30°C. The egg killing rate was 100% in 14 days for all of the rice weevils, cigarette beetles, red flour beetles, and Indian meal moths, demonstrating sufficient egg killing effect.

[0055] [Table 5]

[0056] Table 6 shows the results of the egg killing rate under the conditions of (2) an oxygen concentration of 0.6% or less and a temperature of 30°C. The egg killing rate was 100% for the red flour beetle and Indian meal moth in 2 days, for the maize weevil in 7 days, and for the cigarette beetle in 10 days, demonstrating a sufficient egg killing effect.

[0057] [Table 6]

[0058] Table 7 shows the results of the egg killing rate under the condition (3) where the oxygen concentration was 0.3% or less and the temperature was 30°C. The egg killing rate reached 100% for rice weevils on the fourth day and for cigarette beetles on the sixth day, demonstrating a sufficient egg killing effect.

[0059] [Table 7]

[0060] Table 8 shows the results of the egg killing rate under the conditions of (4) an oxygen concentration of 0.1% or less and a temperature of 30°C. When treating herbal medicines with insecticide and ovicide, it is important to achieve "complete insecticide" (100% insect and ovicide rate) in a short period of time, and for rice weevils and cigarette beetles, the egg killing rate reached 100% on the fourth day, demonstrating sufficient egg killing effect.

[0061] [Table 8]

[0062] It was found that under the same temperature conditions, the lower the oxygen concentration, the higher the ovicidal effect, under treatment conditions (1) to (4). The oxygen concentration should be 3.0% or less, and taking into account the accuracy of oxygen concentration adjustment, it is usually 2% or less, preferably 0.6% or less, and more preferably 0.1% or less.

[0063] Example 3 Tests were conducted to examine the effects of temperature change and treatment period on insecticidal and ovicidal effects. (treated insects) The targets were rice weevils (adults and eggs) and cigarette beetles (adults and eggs). (Processing conditions) The insecticidal rate and egg elimination rate were determined for each period at (1) a temperature of 25°C, (2) a temperature of 28°C, and (3) a temperature of 30°C. In all conditions, the oxygen concentration was 0.1% and the humidity was 70%, and care was taken to ensure that the oxygen concentration and humidity did not affect the insecticidal rate and egg elimination rate. (Test procedure), (determination of survival), (calculation of insecticidal rate), and (calculation of ovicidal rate) were the same as in Examples 1 and 2. (Test results) Table 9 shows the insecticidal and egg-killing rates at temperatures of (1) 25°C, (2) 28°C, and (3) 30°C. For both cigarette beetles and maize weevils, killing of adults took 4 days at 25°C and 3 days at 28°C and 30°C. Killing of eggs took 7 days at 25°C, 5 days at 28°C, and 4 days at 30°C.

[0064] [Table 9]

[0065] Treatment conditions (1) to (3) showed that, under the same oxygen concentration conditions, the higher the temperature, the greater the insecticidal and ovicidal effects. At an oxygen concentration of 0.1% or less, the ovicidal effects were high at all temperatures (1) to (3), but it is best to keep the temperature at 25°C or higher, preferably 28°C or higher, and more preferably 30°C or higher.

[0066] Example 4 Tests were conducted to examine the effects of temperature changes, oxygen concentration changes, and treatment period on herbal ingredients. (Test materials) Dried mint was used. The brand is "Hokuto." Mint is a plant of the mint family, the genus Mentha, and the dried aboveground parts are a typical herbal medicine often used in traditional Chinese medicine prescriptions. It was selected as the test material because it has a leafy shape that easily transmits heat, and also contains a large amount of essential oil components that are important for the efficacy of herbal medicines and are expected to decrease with temperature. (Processing conditions) The samples were stored for two and four weeks under the following conditions: (1) no treatment, (2) temperature 30°C, (3) temperature 40°C, (4) temperature 50°C, and (5) temperature 70°C. The oxygen concentration of (2) to (5) was 0.5% or less. (1) no treatment means storage at a temperature of 20°C or less and with no oxygen concentration adjustment.

[0067] (Low oxygen concentration treatment) For each of the treatment conditions (2) to (5), peppermint was packed into a bag, and a nitrogen gas tube was installed at the bottom of the bag for nitrogen substitution. A constant amount of nitrogen gas was allowed to flow in to maintain the oxygen concentration in each bag below 0.5%, and the bag was then placed in an incubator with the appropriate temperature setting. The bag was then placed in the incubator for the specified period, maintaining the temperature and humidity constant. For treatment condition (1), the peppermint was stored in an aluminum pouch and kept below 20°C. After the specified period, the essential oil content was measured. (Test method for measuring essential oil content) The mint was chopped in accordance with the Japanese Pharmacopoeia Crude Drug Testing Method and the Pharmaceuticals and Medical Supplies Menthol, and the measurement test was carried out.

[0068] (Test results) Figure 5 shows the results of the essential oil content measurement test. The vertical axis represents the essential oil content (ml) per 50 g of test material, and the horizontal axis represents the temperature set as a processing condition. The white bars represent the results after a two-week storage period, while the black bars represent the results after a four-week storage period. Comparing storage periods, a tendency for the essential oil content to decrease with longer storage periods was observed, but the lower the processing temperature, the smaller the difference in the amount of loss in essential oil content. Comparing processing temperatures, the higher the processing temperature, the greater the amount of loss in essential oil content. Compared with the essential oil content of (1) untreated, the essential oil content after two and four weeks of storage at (2) 30°C and (3) 40°C was over 90%, indicating that the effect of temperature was small. The essential oil content of (4) 50°C and (5) 70°C processing conditions was below 90% of that of (1) untreated, indicating that temperature does affect essential oil content. Therefore, it was confirmed that low oxygen concentrations have little effect on the essential oil content when stored at temperatures below 40°C for a period of four weeks or less. The standard for the essential oil content of chopped mint is preferably 1.0 ml / 50 g or more. This test also showed that processing condition (4) at 50°C exceeded this standard. However, in reality, due to sample variation, mint does not necessarily have a high essential oil content. In this case, processing at temperatures above 50°C increases the likelihood of the essential oil content falling below the standard. In other words, the conditions for stable low-oxygen processing without impairing the essential oil content are preferably a temperature of below 40°C and a storage period of four weeks or less.

[0069] Example 5 Tests were conducted to examine the effects of temperature changes, oxygen concentration changes, and treatment period on herbal ingredients. (Test materials) Three lots of Cnidium officinalis rhizomes were used. Cnidium officinalis is a typical herbal medicine often used in traditional Chinese medicine prescriptions. It is made by removing the root hairs from the rhizomes of the Apiaceae plant, blanching them in hot water, and then drying them. It was selected as the test material because it contains essential oils that are expected to decrease with temperature, and a component (ferulic acid) that should be used as an indicator of component changes. (Processing conditions) The treatment conditions were (1) no treatment, (2) storage for two weeks at an oxygen concentration of 0.5% or less and a temperature of 35°C, and (3) storage for four weeks at an oxygen hardness of 0.5% or less and a temperature of 35°C. Note that (1) no treatment means storage under conditions where the temperature is 15°C or less and the oxygen concentration is not adjusted, which are storage conditions generally considered to maintain the quality of herbal medicines, and this corresponds to the storage periods of (2) and (3).

[0070] (Low oxygen concentration treatment) The herbal medicines were packed into zip-top laminated bags, and the air was replaced with nitrogen, and the oxygen concentration inside the laminated bags was adjusted to the values for each treatment condition. After sealing and leaving for one day, the oxygen concentration was measured again to confirm that there was no gas leakage from the laminated bags. The bags were then placed in an incubator for the conditioning period, and the temperature and humidity were kept constant. Furthermore, after storage for the conditioning period, it was confirmed that there was no change in the oxygen concentration or temperature inside the laminated bags. Note that humidity was kept below 60% under all conditions. After storage for the conditioning period, a quality evaluation test was conducted. (Quality evaluation items) TLC, pH, water activity, loss on drying, dilute ethanol, essential oil content, and component determination (ferulic acid) were measured. These items are commonly used to evaluate the quality of herbal medicines.

[0071] (Test results) Table 10 shows the results of the quality test for Senkyu. As shown in the "Properties" section, when comparing (1) untreated and (2) storage conditions of 0.5% or less oxygen concentration, 35°C, and 2 weeks, no differences were observed between the two treatment conditions for any lot or quality evaluation item. Similarly, when comparing (1) untreated and (3) storage conditions of 0.5% or less oxygen concentration, 35°C, and 4 weeks, no differences were observed between the two treatment conditions. Therefore, it was confirmed that there is no effect on the herbal ingredients under conditions of low oxygen concentration, 35°C, and storage for 4 weeks or less.

[0072] [Table 10]

[0073] Example 6 Tests were conducted to examine the effects of temperature changes, oxygen concentration changes, and processing time on the taste of food. (Test materials) Commercially available dried daikon strips and dried green onions were used. Dried daikon strips have a strong sweetness and a characteristic chewy texture, while dried green onions are characterized by their aroma and spiciness. Both were selected as test materials because the change in taste is easy to understand in sensory evaluation. (Processing conditions) Dried daikon radish and dried green onions were stored for at least four weeks under two conditions: (1) no treatment and (2) low-oxygen treatment. (1) No treatment refers to the general storage conditions for herbal medicines, at 15°C, and (2) low-oxygen treatment refers to an oxygen concentration of 0.5% or less and a temperature of 35°C.

[0074] (Low oxygen concentration treatment) Dried daikon radish or dried green onions were packed into a zip-top laminated bag, and nitrogen substitution was performed to adjust the oxygen concentration inside the laminated bag to the value for each treatment condition. After sealing and leaving for one day, the oxygen concentration was measured again to confirm that there was no gas leakage from the laminated bag. The bag was then placed in an incubator for the conditioning period, and the temperature and humidity were kept constant. Furthermore, it was confirmed that there was no change in the oxygen concentration and temperature inside the laminated bag after storage for the conditioning period. After storage for the conditioning period, a quality evaluation test was conducted. Four samples of dried daikon radish and dried green onions were prepared, and 300g of each sample was packed into low-oxygen packaging. (Processing period monitoring) In packages containing (1) untreated and (2) low-oxygen-concentration-treated samples, the oxygen concentration and temperature changes inside the packages were monitored over a treatment period of more than four weeks, and it was confirmed that the oxygen concentration was maintained at 0.5% or less and the temperature was maintained within a range of plus or minus 2°C from the set value.

[0075] (Sensory evaluation method) After the treatment, three out of four samples were used for evaluation (one sample was left as a spare) for each of the two treatment conditions for dried daikon radish and dried green onion. 80 g of each sample was extracted and pooled to make a total of 240 g, which was used as a sample for sensory evaluation (n=1).

[0076] The dried daikon radish was washed in water and soaked for 20 minutes before sensory evaluation, and the dried green onion was soaked in hot water for 2 minutes before sensory evaluation.

[0077] The sensory evaluation was carried out by a panel of 10 people. (sensory evaluation items) (1) Untreated test material was used as the reference sample, and (2) a comparative evaluation was conducted with test material treated with low oxygen concentrations (pair-by-pair method). Dried radish was evaluated based on four criteria: aroma, texture (strength of firmness), sweetness, and overall deliciousness. Dried green onions were evaluated based on five criteria: aroma, texture (firmness), taste (strength of sweetness, strength of spiciness, and overall deliciousness).

[0078] (Sensory evaluation results) Figure 6 shows the sensory evaluation results of dried daikon radish. Figure 7 shows the sensory test results of dried green onions. The average evaluation values of 10 panelists are shown. The vertical axis shows the evaluation value, and an evaluation value of "3" indicates that it is the same as no treatment. The horizontal axis shows the evaluation items.

[0079] As shown in Figure 6, Kiriboshi Daikon radish received a score of 2.5 for "good aroma," 2.7 for "strong texture," 2.4 for "strong sweetness," and 2.5 for "overall deliciousness."

[0080] As shown in Figure 7, dried green onions were rated 2.4 for "good aroma," 2.9 for "firmness," 3.1 for "strength of sweetness," 2.4 for "strength of spiciness," and 2.2 for "overall deliciousness."

[0081] When comparing the sensory evaluation results of both dried daikon radish and dried green onions under the treatment conditions (1) untreated and (2) low-oxygen treatment, no significant differences were observed in any of the evaluation items. Therefore, it was confirmed that conditions of an oxygen concentration of 0.5% or less, a temperature of 35°C, and a storage time of 4 weeks or less do not affect the taste of food. It was suggested that low-oxygen insecticide can be used on food products by performing low-oxygen insecticide immediately before packaging, making it possible to kill insects without impairing the taste.

[0082] Example 7 A test was conducted to confirm the time it takes to heat the target substance to its insecticidal temperature using a blower to blow the atmospheric gas from the treatment chamber onto the target substance. (Processing conditions) Foods, herbal medicines, or their raw materials, which are the target substances for insecticidal treatment, are usually stored in a treatment chamber at 15°C or below to maintain quality. 15°C is referred to as the initial temperature. The lower limit of the insecticidal temperature is 30°C, as determined from the insecticidal tests, ovicidal tests, quality tests, and food sensory tests in Examples 1 to 5. To bring the target substances to the insecticidal temperature, the temperature is raised by approximately 15°C from the initial temperature. This is referred to as Δt15°C. Furthermore, since it is necessary to efficiently raise the temperature of the target substances, the ambient temperature of the treatment chamber is set at approximately 35°C, an additional 5°C higher than the lower limit of the insecticidal temperature. This is referred to as Δt20°C. Note that, according to Examples 1 to 6, Δt20°C is a temperature that is effective for insecticidal treatment while preventing deterioration of the target substances' quality.

[0083] A dryer was used for processing non-glutinous rice.

[0084] The target substance was 80 kg of non-glutinous rice stored at or below 15°C and initially at or below 15°C. After the ambient temperature in the treatment chamber was raised to Δt 20°C, the following treatment conditions were set: (1) air blowing with heating means, (2) air blowing without heating means, and (3) no treatment without heating means or air blowing as a comparison.

[0085] (Test procedure) 80 kg of non-glutinous rice was divided into four drying trays and stored in layers. The bottom of each drying tray was meshed to allow air to pass through. The top of the topmost drying tray was open. A temperature measuring device was installed inside the center of the non-glutinous rice in each drying tray.

[0086] (1) As a method of blowing air with heating means, a blower that emits hot air was placed between the second and third rows of drying trays, and air was blown through it. (2) As a method of blowing air without heating means, an air blower was installed under the bottommost drying tray, and air was blown through it. (3) As a method without treatment, drying trays were stacked in a treatment chamber.

[0087] After the treatment chamber and non-glutinous rice were initially set to a temperature of 15°C, the ambient temperature inside the treatment chamber was raised to Δt 20°C, and measurement of the temperature of the non-glutinous rice began. For each treatment condition, the time it took for all measurements at each temperature measurement point to reach the insecticidal temperature of Δ15°C was measured. Furthermore, for treatment conditions in which Δ15°C had not been reached even after 30 hours from the start of measurement, measurements were continued for up to 182 hours, and if Δ15°C was still not reached, the time to reach Δ15°C was calculated using a linear approximation simulation.

[0088] (Test results) The test results are shown in Figure 8. The vertical axis shows the temperature Δt (°C), and the horizontal axis shows the elapsed time (hours). The results for (1) air blowing with heating means, (2) air blowing without heating means, and (3) no treatment with neither heating means nor air blowing are shown by circles, triangles, and squares, respectively.

[0089] (1) When air was blown with heating means, it took about 6 hours for the temperature of all the non-glutinous rice in each drying tray to reach the insecticidal temperature of Δ15°C. (2) When air was blown without heating means, it took about 22 hours. (3) When no heating means or air was used, the temperature reached after 182 hours was Δ10.8°C. Simulations estimated that it would take 20 days for Δ15°C to be reached.

[0090] In addition, in (1) air blowing with a heating means and (2) air blowing without a heating means, even after reaching Δ15°C, the temperature remained below 40°C, at which the quality of the target substance was guaranteed.

[0091] From the above results, it was confirmed that setting the ambient temperature of the treatment chamber at Δ20°C and blowing air over the target substance is an appropriate method for quickly raising and maintaining the target substance's temperature to the insecticidal temperature of 30°C to 40°C. Furthermore, it was confirmed that blowing air with a heating means is effective in shortening the insecticidal treatment time compared to no treatment.

[0092] The ambient temperature of the treatment chamber is not limited to Δ20°C. For example, by setting the ambient temperature to Δ20°C or higher, blowing air over the target substance, and then lowering the ambient temperature or stopping the air blowing, or both, after the target substance's temperature reaches the insecticidal temperature, further shortening the insecticidal treatment time is expected. Alternatively, the ambient temperature can be set to Δ20°C or lower, and the target substance can be heated by blowing air with a heater or by blowing air with pressure, thereby raising the ambient temperature and supplying it to the target substance.

[0093] Example 8 A temperature rise confirmation test was conducted to confirm the time effect of the supply nozzle for supplying the atmospheric gas of the treatment chamber to the target substance in raising the target substance to its insecticidal temperature. (Processing conditions) Foods, herbal medicines, or their raw materials, which are the target substances for insecticidal treatment, are usually stored in a treatment chamber at 15°C or below to maintain quality. 15°C is referred to as the initial temperature. The lower limit of the insecticidal temperature is 30°C, as determined from the insecticidal tests, ovicidal tests, quality tests, and food sensory tests in Examples 1 to 6. To bring the target substances to the insecticidal temperature, the temperature is raised by approximately 15°C from the initial temperature. This is referred to as Δt15°C. Furthermore, since it is necessary to efficiently raise the temperature of the target substances, the ambient temperature of the treatment chamber is set at approximately 35°C, an additional 5°C higher than the lower limit of the insecticidal temperature. This is referred to as Δt20°C. Note that, according to Examples 1 to 6, Δt20°C is a temperature that is effective for insecticidal treatment while preventing deterioration of the target substances' quality.

[0094] In this case, since the initial temperature of the target substance was around 25°C, the insecticidal temperature Δt15°C of the target substance was set to 40°C, and the ambient temperature of the treatment chamber Δt20°C was set to 45°C.

[0095] The test was conducted using 0.8 t of wheat (bulk density: 0.76 kg / L) as the target material, with the following treatment conditions: (1) blowing air towards the target material, (2) exhausting air from the target material, and (3) no treatment with no blowing or exhausting air as a comparison. (Device) (1) Air blowing to the target material is shown in Figure 1, and (2) air exhaust from the target material is shown in Figure 2. (3) For non-treatment where air blowing and exhaust are not performed, the air collection and supply mechanism and supply nozzle are not included in Figure 1.

[0096] 0.8 t of wheat, which was the target substance 8, was stored in a flexible container, which was the target substance storage container 2. Temperature measuring devices (not shown) were placed in six locations in the target substance storage container 2: two at both ends of one side of the bottom at a position 1 / 4 of the way from the bottom, two at both ends of the side opposite the side placed at the previous 1 / 4 position at a position 1 / 2 of the way from the bottom, one in the center of the previous four locations, and one in the center of the top.

[0097] The ventilation section 42 provided on the supply nozzle 4 is preferably installed near the tip of the supply nozzle 4. The ventilation section 42 is also arranged so as to be located at the bottom of the target substance storage container 2. The location of this ventilation section 42 was clarified through a test to efficiently raise the temperature of the target substance 8. (Test Procedure) After the ambient temperature inside the treatment chamber 1 reached Δt20°C, air was collected and exhausted at a ventilation rate of approximately 1.5 air changes per minute, and the temperature of the target substance 8 was measured. Measurements were carried out for 97 hours, and the time it took for all temperature measurements to reach the insecticidal temperature of Δt15°C was measured under each treatment condition. In addition, for treatment conditions where Δt15°C was not reached, the time it took to reach Δt15°C was calculated using a linear approximation simulation.

[0098] (Test results) The test results are shown in Figure 9. The vertical axis shows the temperature Δt (°C), and the horizontal axis shows the elapsed time (hours). The results for (1) blowing air towards the target material, (2) exhausting air from the target material, and (3) no treatment with no blowing or exhausting air are shown by circles, triangles, and squares, respectively.

[0099] (1) When air was blown onto the target substance, it took approximately 96 hours for all temperature measurement points to reach the insecticidal temperature of Δ15°C. Furthermore, (2) when air was exhausted from the target substance, simulations estimated it would take approximately 130 hours. Furthermore, (3) when no air was blown or exhausted, simulations estimated it would take more than 250 hours.

[0100] It was confirmed that the method of blowing or exhausting air can significantly reduce the treatment time compared to no treatment.

[0101] The flexible container used in this study has 15 threads woven lengthwise and widthwise per inch, making it highly breathable. This allows (1) when blowing air onto the target substance, the low-temperature gas at the initial temperature that was initially inside the flexible container passes through the flexible container and is discharged into the treatment chamber, where it is replaced by low-temperature gas. Also, (2) when exhausting air from the target substance, the atmospheric gas at the insecticidal temperature inside the treatment chamber enters the flexible container through the flexible container, where it is replaced by low-temperature gas at the initial temperature. In this way, the breathability of the storage container that holds the target substance makes it possible to more quickly replace the gas inside the storage container with gas at the insecticidal temperature.

[0102] Example 9 A low-oxygen concentration replacement confirmation test was conducted to confirm the temporal effectiveness of the supply nozzle for supplying the atmospheric gas in the treatment chamber to the target substance in replacing the target substance with a low-oxygen concentration gas, which is an insecticidal concentration. (Processing conditions) The treatment conditions were (1) blowing air into the target material, (2) exhausting air from the target material, and (3) no treatment with neither blowing nor exhausting air. Figure 1 shows the equipment configuration for (1) blowing air into the target material. Figure 2 shows the equipment configuration for (2) exhausting air from the target material. As a comparison between (1) and (2), (3) no treatment with neither blowing nor exhausting air was set. The equipment configuration for (3) does not have the air collection and supply mechanism and supply nozzle in Figure 1. (Device) (1) Air blowing to the target material is shown in Figure 1, and (2) air exhaust from the target material is shown in Figure 2. (3) For non-treatment where air blowing and exhaust are not performed, the air collection and supply mechanism and supply nozzle are not included in Figure 1.

[0103] 800 kg of wheat, the target substance 8, was stored in a flexible container, which was the target substance storage container 2. The oxygen concentration measurement points (not shown) were (1) the bottom of the target substance storage container 2 for blowing air into the target substance and (2) exhausting air from the target substance, and (3) the center of the target substance storage container 2 for the untreated case in which neither blowing nor exhausting air was performed. This measurement point was the measurement point where the temperature rose most slowly under each treatment condition during the temperature rise confirmation test of Example 8. Therefore, this was determined to be the location where replacement with a low-oxygen concentration gas was slowest, and was set as the oxygen concentration measurement point. The location of the supply nozzle 4 is the same as that in the temperature rise confirmation test of Example 8.

[0104] (Test procedure) The treatment chamber 1 was purged with a low-oxygen gas to a concentration of 0.2%. The air collection and supply mechanism (Fig. 1) and the exhaust mechanism (Fig. 2) were used to collect and exhaust air at a ventilation rate of approximately 1.5 air changes per minute, based on the volume of the flexible container. The time required for the oxygen concentration at each measurement point to reach the upper limit of 3.0%, the insecticidal concentration, was measured.

[0105] (Test results) The test results are shown in Figure 10. The vertical axis shows the oxygen concentration (%), and the horizontal axis shows the elapsed time (minutes). The results for (1) blowing air into the target material, (2) exhausting air from the target material, and (3) no treatment with no blowing or exhausting air are shown by circles, triangles, and squares, respectively.

[0106] The time required for each oxygen concentration measurement point to reach the upper limit of 3.0% for insecticidal concentration was (1) 60 minutes when blowing air toward the target substance, (2) 77 minutes when exhausting air from the target substance, and (3) 190 minutes for the untreated control without blowing or exhausting air.

[0107] It was confirmed that the method of blowing or exhausting air can significantly reduce the treatment time compared to no treatment.

[0108] The flexible container used in this study has 15 threads woven lengthwise and widthwise per inch, making it highly breathable. This means that (1) when air is blown onto the target substance, the initial gas that was originally inside the flexible container passes through the flexible container and is discharged into the treatment chamber, where it is replaced with low-oxygen concentration gas. Also, (2) when air is exhausted from the target substance, the low-oxygen concentration gas with insecticidal concentration inside the treatment chamber enters the flexible container through the flexible container, replacing the initial gas. In this way, the breathability of the storage container that holds the target substance makes it possible to more quickly replace the gas inside the storage container with low-oxygen concentration gas.

[0109] Comparing the temperature replacement time in Example 8 with the oxygen replacement time in Example 9, the temperature replacement time required 96 hours, even when air was blown into the target substance. On the other hand, the oxygen replacement time was completed in 190 minutes without treatment. This indicates that the temperature replacement time requires more time than the oxygen replacement time. Therefore, for temperature increase, a heater or other device must be installed in the target substance to actively raise the temperature. On the other hand, for low-oxygen-concentration replacement, if the atmospheric gas is a low-oxygen-concentration gas, replacement with a low-oxygen-concentration gas can be achieved by allowing the low-oxygen-concentration gas to enter the target substance container through the breathable target substance container, without actively replacing the atmospheric gas with air blowing or exhausting. In other words, a mechanism for temperature increase can be actively installed, and a mechanism for oxygen concentration replacement can be omitted, or a simple device can be used.

[0110] Example 10 In accordance with Examples 8 and 9, the following experiments were carried out to confirm a temperature rise and a low oxygen concentration substitution. (Apparatus and conditions) Treatment chamber: Daikin Applied Systems hypoxic insecticide device Processing chamber volume: approx. 6m 3 Oxygen concentration in the treatment chamber: 0.1% Temperature inside the processing chamber (ambient temperature): 35℃ Exhaust acceleration device: Takasu Industrial Turbo Duct Fan T-100 type Exhaust acceleration device displacement: Actual measurement 0.72m 3 / min Initial temperature of the target substance: 15°C

[0111] The test was conducted using 0.2 t of Senkyu (bulk density: 0.49 kg / L) as the target material, with the following treatment conditions: (1) exhausting the target material (using a turbo duct fan T-100 manufactured by Takasu Sangyo), and (2) no treatment without exhausting the material as a comparison. 0.2 kg of target substance 8, Cnidium officinalis, was placed in a flexible container, which was the target substance storage container 2. Temperature measuring instruments (not shown) were placed at six locations in total: the upper left, upper right, lower left, and center of the target substance storage container 2 at the front of the target substance storage container 2 . The oxygen concentration measurement point (not shown) was placed at one location in the center of the target substance storage container 2 . The location of the supply nozzle 4 is the same as in Examples 8 and 9.

[0112] (Temperature test procedure) After the ambient temperature in the treatment chamber 1 reached 35°C, air was collected and exhausted at a ventilation rate of approximately 1.9 air changes / minute, and the temperature of the target substance 8 was measured. The time when all the measured temperatures reached the insecticidal temperature of 30°C was measured. (Oxygen concentration test procedure) The treatment chamber 1 was purged with a low-oxygen gas to a concentration of 0.1%. Using the air collection and supply mechanism shown in Figure 1 and the exhaust mechanism shown in Figure 2, air was collected and exhausted at a ventilation rate of approximately 0.76 air changes / minute, based on the volume of the flexible container. The time required for the oxygen concentration at each oxygen concentration measurement point to reach 0.1% was measured.

[0113] (Test results) (1) When air was exhausted from the target substance, (2) compared to the untreated case where air was not exhausted, a comparison of the cold points of target substance storage container 2 showed that the time required to raise the temperature from the storage temperature of 15°C to the temperature required for insecticidal treatment (30°C) was reduced by 40 hours, from 58 hours to 17 hours. The difference in the time required to reduce the oxygen concentration in the center of the package to 0.1% was approximately 2 hours.

[0114] Example 11 In accordance with Examples 8 and 9, the following experiments were carried out to confirm the temperature rise and the low oxygen concentration substitution. (Apparatus and conditions) Treatment chamber: Daikin Applied Systems hypoxic insecticide device Processing chamber volume: approx. 6m 3 Oxygen concentration in the processing chamber: 0.6% Temperature inside the processing chamber (ambient temperature): 35℃ Exhaust acceleration device: Takasu Industrial Turbo Duct Fan T-100 type Exhaust acceleration device displacement: Actual measurement 0.72m 3 / min Initial temperature of the target substance: 15°C

[0115] The test was conducted using 0.2 t of pinecone (bulk density: 0.76 kg / L) as the target material, with (1) exhaust air from the target material (using a turbo duct fan T-100 manufactured by Takasu Sangyo) and (2) no treatment without exhaust air as a comparison. 0.2 t of target substance 8 was stored in a flexible container, which was the target substance storage container 2. Temperature measuring instruments (not shown) were placed at six locations in total: the upper left, upper right, lower left, and center of the target substance storage container 2 at the front of the target substance storage container 2 . The oxygen concentration measurement point (not shown) was placed at one location in the center of the target substance storage container 2 . The location of the supply nozzle 4 is the same as in Examples 8 and 9.

[0116] (Test procedure) The treatment chamber 1 was purged with a low-oxygen gas until the oxygen concentration reached 0.6%. Using the air collection and supply mechanism shown in Figure 1 and the exhaust mechanism shown in Figure 2, air was collected and exhausted at a ventilation rate of approximately 2.9 air changes per minute, based on the volume of the flexible container. The time required for the oxygen concentration at each oxygen concentration measurement point to reach 0.6% was measured.

[0117] (Test results) (1) When ventilation was removed from the target substance, (2) compared to the untreated control without ventilation, the time required to raise the temperature from the storage temperature of 15°C to the insecticidal temperature (30°C) was reduced by more than 60 hours, from 78 hours to 13.5 hours, in a comparison of the cold points of target substance storage container 2. There was no difference in the time required to reduce the oxygen concentration in the center of the package to 0.6%. [Explanation of symbols]

[0118] 1 Processing facility 2. Container for storing target substances 3. Air collection and supply mechanism 4 supply nozzle 5. Control section 6 Oxygen concentration adjustment unit 7 Gas temperature control section 8. Target substances 9 Exhaust system 10 Heating means 41 Non-ventilated section 42 Ventilation section

Claims

1. a step of substituting the atmosphere of a sealed space in which 10 kg or more of a target substance, which is a plant or a herbal medicine, is stored with an inert gas to reduce the oxygen concentration to 3% or less; a gas temperature adjusting step of adjusting the temperature of the low oxygen concentration gas; a substance temperature adjusting step of adjusting the temperature of the target substance to 30°C or higher; A method for killing insects, comprising: In the substitution step, a first sealed space and a second sealed space inside the first sealed space are provided in the sealed space, and the target substance is stored in the second sealed space; The inert gas is introduced into the second sealed space, The oxygen concentration of the low-oxygen gas in the second sealed space is maintained lower than the oxygen concentration in the first sealed space; In the substance temperature adjusting step, an air collection and supply mechanism that collects the low oxygen concentration gas around the target substance and uniformly supplies the low oxygen concentration gas to the target substance; and An exhaust mechanism that actively exhausts the air around the target substance, thereby uniformly supplying the low-oxygen concentration gas to the target substance. The insecticidal method using the above.

2. 2. The insecticidal method according to claim 1, wherein the temperature of the low oxygen concentration gas is adjusted to 35 to 40°C in the gas temperature adjusting step.

3. 3. The insecticidal method according to claim 1, wherein the air collection and supply mechanism or the exhaust mechanism uses a supply nozzle that is inserted into the target substance and supplies the low-oxygen concentration gas to the target substance at a desired pressure.

4. 4. The insecticidal method according to claim 3, wherein the supply nozzle has a vent for supplying the low-oxygen concentration gas to the target substance, and the vent uses holes or a mesh that is large enough to prevent the target substance from entering.

5. 5. The insecticidal method according to claim 4, wherein the ventilation part is provided near the tip of the supply nozzle.

6. 6. The insecticidal method according to claim 1, wherein the target substance is exposed to the heated low-oxygen concentration gas by a blower equipped with a heating means.

7. The insecticidal method according to any one of claims 1 to 6, wherein the target substance is heated by a device equipped with a heating means.

8. an oxygen concentration measuring step of measuring an oxygen concentration in the target substance or around the target substance; The insecticidal method according to any one of claims 1 to 7, wherein the replacing step adjusts the supply amount of the low-oxygen concentration gas based on the oxygen concentration of the target substance or the vicinity of the target substance.

9. a temperature measurement step of measuring the temperature of the target substance or the surrounding area of the target substance; The insecticidal method according to any one of claims 1 to 8, wherein the gas temperature adjusting step adjusts the temperature of the low oxygen concentration gas based on the temperature of the target substance or the temperature around the target substance.

10. 10. The insecticidal method according to claim 8 or claim 9 which cites claim 8, wherein the replacing step adjusts the supply time of the inert gas based on the oxygen concentration measuring step.

11. 11. The insecticidal method according to claim 9 or 10 which cites claim 9, wherein the gas temperature adjusting step adjusts the temperature of the low-oxygen concentration gas by the temperature measuring step.

12. 12. The insecticidal method according to claim 9, 10 which cites claim 9, or 11, wherein the substance temperature adjusting step adjusts a process time based on the temperature measuring step.

13. The insecticidal method according to any one of claims 1 to 12, wherein the replacing step comprises flowing the inert gas into the sealed space so that the sealed space has a positive pressure compared to the outside of the sealed space.

14. The insecticidal method according to any one of claims 1 to 13, wherein the replacing step actively introduces the inert gas into the sealed space and actively discharges the low-oxygen-concentration gas.

15. The insecticidal method according to any one of claims 1 to 14, wherein the replacement step is to introduce the inert gas so that the pressure in the second sealed space becomes positive compared to the pressure in the first sealed space.

16. The insecticidal method according to any one of claims 1 to 15, wherein the replacing step includes an oxygen adsorption step of adsorbing oxygen in the sealed space.

17. The insecticidal method according to any one of claims 1 to 16, wherein the substance temperature adjustment step continues for 3 days to 3 weeks.

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