JP2018104031A - Container sterilization method and container sterilization device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent as much as possible a sterilizing gas such as hydrogen peroxide from coming into contact with members and equipment of an apparatus and to surely sterilize a packaging container with a small amount of sterilizing gas. The present invention provides a sterilization method capable of avoiding fragments and mercury from being mixed into a container even when the mercury lamp is damaged when the mercury lamp is used as an ultraviolet light source. SOLUTION: An atmosphere control space defined by a defining surface and capable of holding a gas existing in the inside thereof in an airtight or substantially airtight manner, wherein the volume of the space is smaller than the inner volume of the container body. By using a space defining member having at least a part of the demarcating surface, the inner exposed surface of the container main body is brought into contact with a gas containing a sterilizing compound such as hydrogen peroxide present in the atmosphere control space. Then, ultraviolet rays are irradiated toward the internal exposed surface. [Selection] Figure 1

Description

  The present invention relates to a method and a sterilization apparatus for sterilizing containers suitably used for packaging foods and the like.

  Foods, especially liquid foods such as milk, juice, liquor, liquid seasonings, etc. are packaged foods called so-called packed foods or packed beverages filled and packaged in paper containers or plastic containers (packaged foods include packaged drinks) It is often distributed as a concept.

  In manufacturing such packaged foods, in order to prolong shelf life, containers before food filling are sterilized by combining a disinfectant such as hydrogen peroxide and ultraviolet irradiation. Yes.

  For example, Patent Document 1 states that “a disinfectant attaching step of attaching a hydrogen peroxide-containing solution to the inside of a food packaging container having an opening in the upper portion, and irradiating the inside of the container to which hydrogen peroxide has been attached with ultraviolet rays. A UV sterilization step for sterilization, a disinfectant removal step for removing hydrogen peroxide from the inside of the container by spraying an inert gas as a removing gas into the container to which hydrogen peroxide is adhered, and contents inside the container A filling step for filling from the opening; a substitution step for blowing an inert gas as a replacement gas to the upper space in the container filled with the contents to replace the upper space with the inert gas; and A sealing step of sealing the upper opening of the container to seal the container, and distributing the inert gas from the inert gas source to the inert gas of the replacement gas and the inert gas of the removal gas An inert gas supply process to supply Mukoto sterilization method "of food packaging containers, characterized in, it is disclosed.

  Further, Patent Document 2 discloses that “a sheet made of a paper / plastic laminate material is formed into a tube-shaped container blank, and the formed tube-shaped container blank having end surfaces and side surfaces is used for injection molding of a thermoplastic material. The step of providing, the step of subjecting the inside of the container to a bacteria-reducing treatment with hydrogen peroxide with the aid of ultraviolet irradiation, the step of filling the container with the content, and the step of sealing the container, A method for producing a packaging container with low bacterial contamination is disclosed.

  Furthermore, Patent Document 3 states that “(a) a hydrogen peroxide-containing gas having a temperature of 10 to 60 ° C. and a concentration of 10 to 200 ppm is jetted into a packaging container to be sterilized, and hydrogen peroxide is brought into contact with the inner surface of the packaging container. (B) a step of irradiating the inner surface of the packaging container with ultraviolet rays; and (c) aseptic air having a temperature of 10 to 60 ° C. is jetted into the packaging container to replace the hydrogen peroxide-containing gas in the packaging container with air. A method for sterilizing a packaging container comprising a purging step.

JP 2004-59014 A US 6,338,235B1 publication International Publication No. 2013/008426

  According to the methods described in Patent Documents 1 and 2, sterilization can be performed in a short time due to the synergistic effect of hydrogen peroxide used as a sterilizing agent and ultraviolet irradiation. Further, according to the method described in Patent Document 3, by using a hydrogen peroxide-containing gas, it is possible to reliably sterilize a container having a complicated shape as compared with the case where a mist of hydrogen peroxide is sprayed. In addition, the energy cost required for removing hydrogen peroxide can be reduced.

  However, in these methods, when the hydrogen peroxide solution mist is sprayed on the container, the attached hydrogen peroxide solution mist is dried and removed, or when the hydrogen peroxide gas is jetted into the packaging container, the peroxide is oxidized. It is inevitable that hydrogen leaks out of the container. For this reason, the loss of hydrogen peroxide is large, and not only the amount of hydrogen peroxide used is increased, but also the burden of labor and cost for the hydrogen peroxide detoxification treatment is increased. In addition, such leakage may damage the peripheral members and electrical equipment of the sterilizer used by contact with hydrogen peroxide having a chemical action. Damage accumulates and shortens the life of these components and equipment. Furthermore, since a mercury lamp is used as an ultraviolet light source, there is a risk that fragments or mercury may enter the container if it is damaged.

  Therefore, the present invention solves the above-mentioned problems and not only can reduce the amount of sterilizing gas such as hydrogen peroxide to be used to reliably sterilize the packaging container, Sterilization method and sterilization that prevents contact with equipment as much as possible, and that when a mercury lamp is used as an ultraviolet light source, even if the mercury lamp breaks, fragments and mercury are not mixed into the container. An object is to provide an apparatus. Furthermore, it aims at providing the method which can manufacture a packaged food safely and efficiently using these sterilization methods or sterilization apparatuses.

  The sterilization method of the present invention achieves the above-mentioned object, and is a method for sterilizing a container having a bottomed cylindrical container body having an opening, and is defined by (A) a demarcating surface and exists inside the container. A space demarcation member having at least a part of the demarcation surface is used as an atmosphere control space that is a space that can hold gas in an airtight or substantially airtight space, the volume of the space being smaller than the inner volume of the container body. And a space demarcating step for demarcating the surface to be sterilized, which is an exposed internal surface of the container body, in contact with the gas present in the atmosphere control space, and (B) the atmosphere control demarcated in the space demarcating step A sterilizing gas introduction step for introducing a sterilizing gas into the space and making the atmosphere inside the atmosphere control space an atmosphere of a sterilizing gas having a predetermined concentration; and (C) contacting the sterilizing gas having the predetermined concentration. Wherein an ultraviolet irradiation step of irradiating ultraviolet rays onto the sterilization surfaces, characterized in that it comprises a, and fungicidal gas discharge step of discharging a sterilizing gas present in the (D) the atmosphere control chamber.

  In the sterilization method of the present invention, it is preferable that at least a part of the sterilizing gas discharged in the (D) sterilizing gas discharging step is reused in the (B) sterilizing gas introducing step.

  In the sterilization method of the present invention, in the (A) space defining step and (C) ultraviolet irradiation step, the atmosphere control space is defined and ultraviolet irradiation is performed as shown in (1) or (2) below. Is preferred.

  (1) The space-defining member is made of an ultraviolet light-transmitting material, has one end opened, and a bottomed cylindrical body having a bottom at the other end, and a collar provided around the opening edge of the body A space-defining portion having a shape and a contact seal portion provided in the space-width defining portion, and the body portion can be inserted into the container body through an opening of the container body. Using a member (also referred to as a hat-type space determining member), the contact seal portion is brought into contact with the one end or the externally exposed surface of the container body, and the surface to be sterilized constitutes a part of the defining surface. In this way, the atmosphere control space is defined, and ultraviolet irradiation is performed from the outside of the atmosphere control space.

  (2) In the case of sterilizing the container placed on the placement surface with the opening of the container body facing upward, the space demarcating member is made of an ultraviolet transmissive material, and one end is opened, A bottomed cylindrical inner trunk having a bottom at the other end, a bowl-shaped space width defining portion provided around the opening edge of the inner trunk, and one end sealed by the space width defining portion, A cylindrical outer body having an opening at the other end, and an abutting seal provided at an opening edge of the outer body, and the space between the outer body and the inner body By using a space demarcating member (also referred to as a cover-type space determining member) that can accommodate the container body, the container body is accommodated in the atmosphere control space by bringing the seal portion into contact with the placement surface. The atmosphere control space is defined as described above, and the outside of the atmosphere control space Perform Luo UV irradiation.

  The method for producing a packaged food of the present invention is a method for producing a packaged food in which a food is filled and packaged in a container having a bottomed cylindrical container body having an opening, and the sterilization of the present invention A step of sterilizing the container by a method; a step of filling a container sterilized by the step; and a step of sealing the opening of the container filled with food. To do.

Furthermore, the sterilization apparatus of the present invention is a sterilization apparatus for sterilizing a surface to be sterilized consisting of an inner exposed surface of the container body of a container having a bottomed cylindrical container body having an opening,
A space defined by a defining surface and capable of holding gas existing in the inside thereof in an airtight or substantially airtight manner, wherein the volume of the space is smaller than the inner volume of the container body. Atmosphere control space defining means; gas introduction means for introducing gas into the atmosphere control space; and gas discharge means for discharging gas in the atmosphere control space;
A sterilizing gas source for supplying a sterilizing gas, a replacement gas supply source for supplying a replacement gas consisting of sterilized inert gas or sterilized air, and ultraviolet irradiation means,
The atmosphere control space defining means is (1) made of an ultraviolet light transmissive material, and has a cylindrical body with a bottom having one end opened and a bottom at the other end, and is provided around an opening edge of the body. A bowl-shaped space width defining portion and a contact seal portion provided in the space width defining portion, and the body portion can be inserted into the container body through the opening of the container body. A space-defining member, and the abutting seal portion is brought into contact with an externally exposed surface at or near the one end of the container body so that the surface to be sterilized constitutes a part of the defining surface. The atmosphere control space is defined, or (2) a bottomed cylindrical inner body made of an ultraviolet light transmissive material, having one end open and a bottom at the other end, and the inner body A flange-shaped space width defining portion provided around the opening edge of the portion, and one end is sealed by the space width defining portion. A cylindrical outer body having an opening at the other end, and an abutting seal provided at an opening edge of the outer body, and the space between the outer body and the inner body The container main body having a space demarcating member that can accommodate the container main body and placed on the placement surface with the opening of the container main body facing upward is applied with the contact seal portion against the placement surface. The atmosphere control space is demarcated so that the container main body is accommodated in the atmosphere control space by contacting the container body,
The ultraviolet irradiation means irradiates the surface to be sterilized, which is in contact with the gas existing inside the atmosphere control space, from outside the atmosphere control space.

  According to the sterilization method and the sterilization apparatus of the present invention, only the inside of the atmosphere control space whose volume is smaller than the internal volume of the container body is used as the atmosphere of the sterilizing gas, and the surface to be sterilized is brought into contact with the sterilizing gas. Because irradiation is performed, the amount of sterilizing gas used can be reduced, and the time required for gas replacement (introduction of sterilizing gas, exhaust, and replacement of atmospheric gas with sterile nitrogen gas or sterile air) is greatly reduced. can do. And also when performing the detoxification process of sterilizing gas, the effort and cost concerning it can be reduced.

  In addition, since the sterilizing gas does not come into contact with the members and equipment of the apparatus, it is possible to avoid deterioration of these members and failure of the equipment due to contact with the sterilizing gas. Furthermore, by arranging an ultraviolet irradiation device outside the atmosphere control space and performing ultraviolet irradiation, even if a mercury lamp is used and it is damaged, fragments and mercury are not mixed into the container.

  Furthermore, when the sterilizing gas is reused, the total amount of the sterilizing gas when the container is repeatedly sterilized over a long period of time in a continuous process can be extremely reduced. As a result, even when performing the detoxification process of the sterilizing gas, it is possible to minimize the labor and cost.

  Moreover, according to the manufacturing method of the packaged food of the present invention, the packaged food can be efficiently manufactured in response to the effect of the present invention.

This figure is a schematic diagram for explaining the sterilization method of the present invention using a hat-type space defining member. This figure is a schematic diagram for explaining a sterilization method of the present invention using a plurality of hat-shaped space defining members of another form. This figure is a schematic diagram for explaining the sterilization method of the present invention using a cover type space defining member. This figure is a schematic diagram of a preferred embodiment in the method for producing a packaged food of the present invention. This figure is a schematic diagram of another suitable aspect in the manufacturing method of the packaged food of this invention.

  The sterilization method of the present invention produces packaged foods called so-called packed beverages and packed foods, in which paper containers and plastic containers are filled with beverages such as milk, juice, liquor, and foods such as soup, yogurt, and liquid seasonings. It can employ | adopt suitably for the container sterilization process at the time.

  As described in Patent Documents 1 and 2, the packaged food is generally manufactured by the following method. That is, first, a folded packaging container blank (for example, as shown in Fig. 1A of Patent Document 2) is used as a bottomed open container (for example, as shown in Fig. 1B of Patent Document 2, or a diagram of Patent Document 1). 1 to 4 (designated by reference numeral 1). Then, after filling the bottomed open container with food, the top seal part provided on the top of the bottomed open container is adhered by heat sealing, so that the final container-shaped container is filled with food. It is considered as a packaged packaged food.

  The sterilization method and the sterilization apparatus of the present invention provide an inner exposed surface (surface to be sterilized) of the container main body in the above-mentioned bottomed open container, that is, “a container having a bottomed cylindrical container main body having an opening” in the present invention. The present invention relates to a method and apparatus for sterilization.

  As the final form of the packaged food obtained by the above-described method, the Gobeltop type disclosed in Japanese Patent No. 5831172, Japanese Patent Application Laid-Open No. 2014-108821, Japanese Patent Application Laid-Open No. 2006-179841, and the like. Liquid paper containers and flat top types are known. And these patent documents also describe packaging container blanks of various containers and bottomed open containers obtained therefrom. In the sterilization method of the present invention and the packaged food manufacturing method of the present invention, such conventionally known packaging container blanks and bottomed open containers are not particularly limited and can be used.

  In addition, as a method for producing a bottomed open container from packaging container blanks, a conventionally known method can be used without any particular limitation. For example, Patent Document 1 describes such a method as follows: “Container blanks are made of a flexible thin plate in which resin materials are laminated on both sides of a paper material in a substantially rectangular tube shape, and are folded flat. The two sides of the packaging container blanks constitute a thermoplastic layer for bonding, and the blanks are filled with a number of fold lines, and the fold lines form side walls. The molding means 2 includes a mandrel wheel, a bottom heater, and a bottom pressurizing device.The mandrel is divided into a panel, a bottom wall panel on the bottom side, and a top wall panel on the top side. The vehicle includes a core portion that is intermittently driven to rotate, and a plurality of mandrels 21 that are radially arranged around the core portion.The blanks are lifted from the magazine and are rectangular cylinders having a substantially square cross section. Condition Supplied to the mandrel 21. The packaging container 1 mounted on the mandrel 21 is heated by the bottom heater, the bottom of the packaging container 1 is heated, the bottom is pressed by the pressurizing device, cooled, and sealed without water leakage. The bottom of the state is formed. " The bottomed open container manufactured in the same manner can also be used in the sterilization method and the packaged food manufacturing method of the present invention.

  The sterilization method of the present invention is a method for sterilizing a container having a bottomed cylindrical container body having an opening, and (A) is defined by a defining surface and holds gas existing therein in an airtight or substantially airtight manner. A space defining member having at least a part of the demarcating surface, and an internal space of the container main body exposed to an atmosphere control space composed of a space that is smaller than an inner volume of the container main body. A space defining step in which the surface to be sterilized is defined so as to come into contact with the gas existing in the atmosphere control space; and (B) the sterilizing gas is introduced into the atmosphere control space defined in the space defining step. Introducing a sterilizing gas introducing step, wherein the atmosphere inside the atmosphere control space has an atmosphere of a sterilizing gas having a predetermined concentration; and (C) applying ultraviolet rays to the surface to be sterilized in contact with the sterilizing gas having the predetermined concentration. Light And an ultraviolet irradiation step of, characterized by comprising a sterilizing gas discharge step of discharging a sterilizing gas present in the (D) the atmosphere control chamber.

  Here, the container is not particularly limited as long as it has a bottomed cylindrical container body having an opening, and a member such as a spout member may be attached to the container body. As such a container, the bottomed opening container manufactured from the above-mentioned packaging container blanks can be used.

  In the sterilization method of the present invention, first, the atmosphere control space is defined in the (A) space defining step. Here, the atmosphere control space is a space defined by a defining surface, which can hold gas existing therein in an airtight or substantially airtight manner, and the volume of the space is smaller than the internal volume of the container body. It means space. The volume of the atmosphere control space is preferably as small as possible within a range where gas replacement in the space can be easily performed, and is usually 3% to 60%, preferably 5% to 50% of the internal volume of the container body. More preferably, it is 5% or more and 30% or less.

  In defining the atmosphere control space, a space defining member having at least a part of the defining surface is used so that the surface to be sterilized, which is an exposed surface inside the container main body, comes into contact with the gas existing in the atmosphere control space. Thus, it is necessary to define the atmosphere control space.

  The space defining member has a surface that becomes at least a part of the defining surface, and the atmosphere alone or in cooperation with (in combination with) the container body or the holding means for holding the container body Any part can be used as long as it can form a control space. However, from the viewpoint that ultraviolet irradiation can be performed from the outside of the atmosphere control space, it is preferable that the part facing the surface to be sterilized has ultraviolet transparency.

  As a space demarcating member that can be suitably used in the sterilization method and sterilization apparatus of the present invention, it is composed of an ultraviolet light transmissive material, one end is open, and the bottomed cylindrical body having a bottom at the other end, A flange-like space width defining portion provided around the opening edge of the body portion, and a contact seal portion provided in the space width defining portion, wherein the body portion is more than the opening of the container body. A bottom-defining cylindrical inner body made of a space-defining member (hat-type space determining member) that can be inserted into the container and an ultraviolet light transmissive material, having one end open and the other end having a bottom; A flange-shaped space width defining portion provided around the opening edge of the inner body portion, a cylindrical outer body portion having one end sealed by the space width defining portion, and the other end opened, and the outer body portion A contact seal portion provided at an opening edge of the portion, and in a space between the outer body portion and the inner body portion. Can be mentioned space defining member serial container body can accommodate (cover spatial confirm member).

  The ultraviolet transmissive material means a material having transparency to ultraviolet rays in a wavelength region of 200 nm to 400 nm. Examples of ultraviolet transmissive materials include inorganic materials such as sapphire, natural or synthetic quartz, calcium fluoride, magnesium fluoride, and glass, fluorine resins such as PFA, FEP, ETFE, and PTFE, polyethylene, polypropylene, PVC, and polycarbonate. An organic material and a composite material thereof (for example, an exposed surface of calcium fluoride or magnesium fluoride coated with a fluorine-based resin) can be preferably used.

  Also, polyolefin resins such as polyethylene, polypropylene, polymethyl terpene or polyolefin copolymer resins, fluorine resins such as polytetrafluoroethylene, tetrafluoroethylene perfluoroalkyl vinyl ether copolymers, methacrylic resins, polytetrafluoroethylene, Epoxy resin, alicyclic polyimide resin, polyamide resin, polyvinyl chloride, polyvinyl alcohol resin, etc. (all do not contain additives such as UV absorbers and plasticizers that absorb UV rays irradiated in the UV irradiation process) It is also possible to use a flexible material. These ultraviolet light transmitting resins may be used alone or in a composite form such as a laminate. Regarding the ultraviolet transmittance of the resin film, “Touzo Matsui, Yoshihiro Shimizu,“ UV Transmissivity of Plastic Film II ”, Toyo Foods Institute, Toyo Food Research Laboratory, 102-111 (1967)” , “Daikin Industries, Ltd. Technical Document GX-27e“ Neofrene ™ Film ”” and http://jp.mitsuichem.com/service/functional_polymeric/polymers/tpx/spec.htm.

  The portion composed of the ultraviolet light transmissive material has a transmittance of ultraviolet rays having a wavelength corresponding to the main peak of 30.0% or more and 99.99% when ultraviolet rays having single or plural peaks in 200 nm to 400 nm are transmitted. It is preferably 5% or less, more preferably 50% or more and 98% or less, and particularly preferably 60% or more and 97% or less.

  In the sterilization method of the present invention, next, (B) the sterilizing gas is introduced into the atmosphere control space defined in the space defining step, and the atmosphere inside the atmosphere control space is changed to an atmosphere of sterilizing gas having a predetermined concentration. The sterilizing gas introduction process is performed.

  The bactericidal gas is not particularly limited as long as it is a compound gas having bactericidal properties. Examples of such a compound include ozone, ethylene oxide, hydrogen peroxide, and chlorine dioxide. Among these, it is particularly preferable to use hydrogen peroxide because a synergistic effect by ultraviolet irradiation can be expected. These compounds are used by diluting them to a predetermined concentration using an inert gas such as nitrogen gas or a dilution gas composed of air or the like. At this time, it is preferable that the inert gas or air serving as the dilution gas is previously sterilized by removing foreign substances with a filter or the like.

  The introduction of the bactericidal gas into the atmosphere control space is provided with a gas introduction part and a gas discharge part in the space demarcating member, and the gas (for example, air) existing in the atmosphere control space is exhausted using a vacuum pump or the like, Subsequently, a gas containing a sterilizing gas at a predetermined concentration is introduced into the atmosphere control space from the gas introducing unit, or a gas containing a sterilizing gas at a predetermined concentration is introduced from the gas introducing unit, thereby The gas (for example, air) present in the gas can be pushed out and exhausted from the gas exhaust unit. The gas containing the sterilizing gas at a predetermined concentration is adjusted so as to have a predetermined concentration by diluting the sterilizing gas with a diluting gas in order to make the atmosphere of the sterilizing gas with a predetermined concentration in the atmosphere control space. It is preferable to introduce from.

  For example, a sterilizing gas containing hydrogen peroxide can be produced by evaporating hydrogen peroxide water and diluting with sterile air or sterile nitrogen gas as necessary. Specifically, for example, a hydrogen peroxide gas generating apparatus as described in International Publication No. 2011-125823 or Patent Document 3 can be used. When a sterilizing gas containing hydrogen peroxide is used as the sterilizing component, the hydrogen peroxide concentration in the sterilizing container is preferably 1 ppm to 1000 ppm, and particularly preferably 10 to 200 ppm.

  When ethylene oxide is included as a sterilizing component, the concentration is preferably 100 to 2000 ppm, and more preferably 450 to 1200 ppm. When ozone is contained as a sterilizing component, the concentration is preferably 0.5 to 10 ppm, and particularly preferably 1 to 3 ppm. When chlorine dioxide is included as a sterilizing component, the concentration is preferably 0.01 to 10 ppm, and particularly preferably 0.01 to 1 ppm.

  Since the atmosphere control space is defined so that the surface to be sterilized (the exposed surface inside the container body) is in contact with the gas existing in the atmosphere control space, (B) the sterilizing gas introduction step ends. Thereafter, the surface to be sterilized comes into contact with an atmospheric gas containing a sterilizing gas at a predetermined concentration. At this time, when the atmospheric gas contains moisture, water in which the sterilizing compound, which is a sterilizing component, dissolves may aggregate and adhere to the surface to be sterilized. Thus, “the surface to be sterilized is in contact with an atmospheric gas containing a sterilizing gas at a predetermined concentration”.

  (C) In the ultraviolet irradiation step, the surface to be sterilized in contact with the sterilizing gas having the predetermined concentration is irradiated with ultraviolet rays. Because the ultraviolet irradiation means does not come into contact with the bactericidal gas, and even if they are broken, fragments and the like do not enter the container body. It is preferable to arrange outside the atmosphere control space and irradiate ultraviolet rays from outside the atmosphere control space.

  As an ultraviolet light source of the ultraviolet irradiation means, a UV lamp such as a mercury lamp or an excimer lamp well known as a light source of ultraviolet light having a wavelength of 200 nm to 400 nm (hereinafter, ultraviolet light may be abbreviated as UV), ultraviolet light A light emitting diode (hereinafter sometimes abbreviated as UV-LED) or the like can be used.

  Among these light sources, it is preferable to use a UV-LED because it is compact, saves power, has a long life, does not use mercury, and can be turned on and off instantaneously. The UV-LED is preferably a UV-LED that emits ultraviolet light having a wavelength of 250 nm to 300 nm, and is particularly preferably a UV-LED that emits ultraviolet light of 250 nm to 280 nm.

  In the ultraviolet irradiation step, the ultraviolet light emitted from these ultraviolet light sources may be directly irradiated, or the ultraviolet light irradiation means may be configured using the ultraviolet light source, for example, the ultraviolet light may be irradiated from the ultraviolet light emitting surface of the light guide plate, Ultraviolet light may be optically transmitted to the ultraviolet ray emitting part using an optical fiber, and the ultraviolet ray may be irradiated from the ultraviolet ray emitting part.

Ultraviolet irradiation conditions may be set as appropriate according to the light source used and the type and concentration of the bactericidal gas. However, a wavelength region (usually effective for inactivating microorganisms such as bacteria by damaging the DNA) Since the cumulative irradiation amount (unit: mJ / cm ² ) of ultraviolet rays of 250 nm or more and 300 nm or less, preferably 250 nm or more and 280 nm or less) is known, the microorganisms assumed on the surface to be sterilized are inactivated. The condition for irradiating with the “required integrated dose” of ultraviolet rays is a standard. Normally, it is particularly preferable that the it is preferable to so integrated irradiation dose of ultraviolet rays of such a wavelength region in the sterilizing surface is 50 mJ / cm ² or more, a 100 mJ / cm ² or more. However, when the bactericidal properties of the sterilizing component are extremely high and ultraviolet irradiation is auxiliary, or when the synergistic effect with ultraviolet irradiation is high, ultraviolet irradiation that does not satisfy the “required integrated dose” may be used. Irradiation time is the irradiance (unit: mW) on the surface to be sterilized by combining the output of the light source, the output of the ultraviolet light emitting surface and the ultraviolet light emitting portion, the distance from these to the surface to be sterilized, the ultraviolet transmittance of the space demarcation member, etc. / Cm ² ), and a time such that the product of time (unit: seconds) becomes the integrated irradiation dose may be used as the irradiation time.

  When the bactericidal gas contains hydrogen peroxide as a bactericidal component, the wavelength of the microorganism is out of the effective wavelength range for damaging the DNA and inactivating it, and the wavelength 250 nm on the shorter wavelength side than the wavelength range. Hereinafter, it is possible to efficiently generate OH radicals from hydrogen peroxide by irradiating ultraviolet rays having a short wavelength of preferably 210 to 240 nm. Therefore, when a UV-LED that emits ultraviolet light having a wavelength of 250 nm or more and 300 nm or less is used as the ultraviolet light source, in order to obtain such an effect, ultraviolet light having a wavelength of 200 nm or more and less than 250 nm is combined with the ultraviolet light in the wavelength region. It is preferable to use a UV-LED that emits light.

  Finally, in the sterilization method of the present invention, (D) a sterilizing gas discharging step of discharging the sterilizing gas existing in the atmosphere control space is performed. The discharge of the sterilizing gas from the atmosphere control space is performed by introducing a replacement gas comprising an inert gas such as nitrogen gas sterilized in advance or air sterilized in advance from a gas introduction part provided in the space defining member. At the same time, an atmospheric gas containing an inert gas may be discharged from the gas discharge portion. At this time, the surface to be sterilized may be heated by irradiating infrared rays from the outside of the atmosphere control space using an infrared lamp. By doing so, it is possible to discharge the inert gas reliably and in a short time even when water containing a sterilizing component adheres to the surface to be sterilized. The same effect can be obtained by preheating the replacement gas. As the replacement gas, the same gas as the dilution gas can be used.

  Since the exhaust gas containing the exhausted germicidal gas is the one in which the atmosphere gas after the (B) germicidal gas introduction step is extruded with a replacement gas, the concentration of the germicidal gas becomes lower than the predetermined concentration. It contains bactericidal gas that is effective for sterilization The exhaust gas is discharged into the atmosphere after being subjected to a treatment for detoxifying the germicidal gas by adsorption or decomposition. According to the sterilization method of the present invention, since the sterilizing gas is introduced only in the narrow atmosphere control space, the amount of the sterilizing gas to be used can be reduced, and the labor and time required for these places are reduced. Can be greatly reduced.

  In addition, the sterilizing gas contained in the exhaust gas can be reused. At the time of reuse, it may be used as a part of the dilution gas used in the (B) bactericidal gas introduction step by performing a filter treatment as necessary. By doing so, the burden of the above processing can be further reduced.

  (D) After completion of the sterilizing gas discharge step, the engagement between the container main body and the space defining member may be released. Thereafter, for example, when performing the packaged food manufacturing method of the present invention using the sterilization method of the present invention, the step of filling the sterilized container with the food and the opening of the container filled with the food are sealed. And the step of stopping. The filling process and the sealing process are not particularly different from the conventional method. For example, the filling process stores a filling material such as a filling nozzle and a beverage as in the method disclosed in Patent Document 1. It can be performed using a filling means having a tank, a flow pipe connecting the tank and the filling nozzle, a pump, a lifter and the like. In addition, the sealing step may be performed by a heat sealing method, an ultrasonic fusion method, or the like on the top seal portion provided on the upper portion of the container body using a sealing means including a heat sealing heater and a pressurizing device. it can.

  Hereinafter, with reference to the drawings, the sterilization method of the present invention and the packaged food production method of the present invention will be described with a focus on the sterilization apparatus of the present invention.

The sterilization apparatus of the present invention is a sterilization apparatus for sterilizing a surface to be sterilized 13 consisting of an exposed internal surface of the container body 11 of a container 10 having a bottomed cylindrical container body 11 having an opening 12.
A space defined by the demarcation surface 41 and capable of holding the gas existing inside thereof in an airtight or substantially airtight manner, wherein the volume of the space is smaller than the internal volume of the container body, thereby defining an atmosphere control space 20. Atmosphere control space defining means 30 for gas, gas introduction means 46 for introducing gas into the atmosphere control space 20, gas discharge means 47 for discharging gas in the atmosphere control space 20, and sterilizing gas A sterilizing gas source (not shown) for supplying gas, a replacement gas supply source (not shown) for supplying replacement gas made of sterilized inert gas or sterilized air, and ultraviolet irradiation means 50 Have
The atmosphere control space defining means 30 includes (1) a bottomed cylindrical body portion 42 made of an ultraviolet light transmissive material, having one end opened and a bottom at the other end, and a periphery of the opening edge of the body portion. A bowl-shaped space width defining portion 43 provided, and an abutting seal portion 45 provided in the space width defining portion, and the body portion 42 is formed on the container body from the opening 12 of the container body. A space-defining member (hat-type space determining member) 40 that can be inserted into the container body, and the contact seal portion 45 is brought into contact with the externally exposed surface at or near the one end of the container body to The atmosphere control space 20 is defined such that a sterilizing surface constitutes a part of the defining surface 41, or (2) is configured by an ultraviolet light transmissive material, one end is open, and the other end A bottomed cylindrical inner body 42 ′ having a bottom and an opening edge of the inner body An eaves-like space width defining portion 43 ′ provided, a cylindrical outer body portion 44 whose one end is sealed by the space width defining portion 43 ′ and the other end is opened, and an opening of the outer body portion 44 A space-defining member (cover type) that can accommodate the container body 11 in a space between the outer body portion 44 and the inner body portion 42 ′. The container main body 11 having the space determining member 40 ′ and placed on the placement surface 61 with the opening of the container main body 11 facing upward is placed on the placement surface 61 on the contact seal portion 45 ′. The container main body 11 is accommodated in the atmosphere control space 20, and the atmosphere control space 20 is defined.
The ultraviolet irradiation means 50 irradiates the surface to be sterilized 12 that is in contact with the gas existing inside the atmosphere control space 20 with ultraviolet rays from the outside of the atmosphere control space 20.

  FIG. 1 is a schematic diagram for explaining a method of sterilizing the surface 12 to be sterilized using an apparatus having a hat-type space determining member 40. FIG. 1 is a vertical cross-sectional view when the container body 11 and the hat-type space determining member 40 are engaged to form the atmosphere control space 20, and the cross section is held with the opening 12 facing upward. The state of sterilizing the inner wall surface, that is, the inner side surface 14 and the inner bottom surface 15 of the bottomed quadrangular columnar container body 11 is shown. In FIG. 1, a hat-type space determining member 40 having a body portion 42, a bowl-shaped space width defining portion 43, and a contact seal portion 45 provided in the space width defining portion 43 is used. The section 42 is a square whose cross section is shorter by 2 × Δw than one side of the square of the opening shape of the container body 11 and whose height is shorter by Δh than the height of the container body 11. It has a shape of a bottom quadrangular prism, and the whole is made of an ultraviolet light transmissive material. Therefore, the barrel part 42 can be inserted into the container body 11. Further, when this is inserted, the inner wall surface of the container body faces the side wall and the bottom of the body portion 42, and the inner wall surface of the container body can be irradiated with ultraviolet rays through the body portion 42.

  The space width defining portion 43 is preferably made of an ultraviolet shielding material such as metal, and the surface exposed to the atmosphere control space 20 is preferably made of an ultraviolet reflecting material. Moreover, although it is preferable that the cross-sectional shape of the trunk | drum 42 is similar to the shape of the said opening 12, if it can insert from the opening 12, a tank shape will not be limited, For example, circular may be sufficient.

  A gas introduction line having a gas introduction side partition valve 461 as gas introduction means 46 is connected to the hat-type space determination member 40, and the gas introduction line is branched upstream of the gas introduction side partition valve 461. The introduction side line switching valve 462 can be switched to a sterilizing gas / dilution gas mixed gas introduction line 463 and a replacement gas introduction line 464.

  Further, a gas discharge line having a gas discharge side partition valve 471 as a gas discharge means 47 is connected to the hat-type space determination member 40, and the gas discharge line branches downstream from the gas discharge side partition valve 471. The gas discharge side line switching valve 472 can be switched to the sterilizing gas / dilution gas mixed gas discharge line 473 and the air / substitution gas discharge line 474.

  In order to perform sterilization, it is first necessary to demarcate the atmosphere control space 20 as (A) space demarcating step. The demarcation is performed as follows. That is, the hat-shaped space determining member 40 is moved closer to the predetermined position from above the container body 11 placed with the opening 12 facing upward, and the body portion 42 is moved from the opening 12 to the container body 12. The contact seal portion 45 is inserted into the container body 11 until it contacts the open end of the container body 11. The contact seal portion 45 has a groove shape so that the opening end portion of the container body 11 is fitted therein, and a seal member made of silicone rubber, fluorine rubber, or the like is disposed therein. The seal member comes into contact with the open end of the container main body 11 so that the gas is substantially leaked from the contact portion when the gas flows in the atmosphere control space 20. It is designed to maintain a level of airtightness that does not occur. The structure of the contact seal portion 45 is not limited to this as long as airtightness or substantially airtightness is maintained. For example, the container wall near the opening end of the container body 11 is sandwiched, It may be a clamp that keeps hermeticity by narrow pressure.

  In this way, the barrel portion 42 is inserted into the container body 11 so as to have a gap Δw from the inner side surface 14 of the container body 11 and a gap Δh from the inner bottom surface 15 of the container body 11. As a result, the atmosphere control space 20 is defined in which the inner side surface 14 and the inner bottom surface 15 of the container main body, the inner wall surface of the body portion 42, and the inner surface of the abutting seal portion 45 on the back side of the space width defining portion 43 are defined surfaces 41. Is done.

  After the atmosphere control space 20 is formed by the engagement of the hat-type space determining member 40 and the container body 11, the air of the gas discharge means 47, the replacement gas discharge line 474, and the sterilizing gas / dilution gas of the gas introduction means 46 The mixed gas introduction line 463 is connected (communicated) with each other, and the sterilizing gas / diluted gas mixed gas whose concentration of the sterilizing gas is adjusted to a predetermined value by the diluting gas is introduced into the atmosphere control space 20, and simultaneously from the beginning. By discharging the air that has entered the atmosphere control space 20, the atmosphere control space 20 is made a gas atmosphere having a predetermined concentration of the sterilizing gas {(B) sterilizing gas introduction step}. At this time, a predetermined concentration may be obtained by introducing a mixed gas of a sterilizing gas / dilution gas having a concentration higher than a predetermined concentration and mixing with a preexisting air. Further, the predetermined concentration may have a certain range, and basically may be a suitable concentration range according to the type of the sterilizing gas.

  In addition, the preparation of the sterilizing gas / dilution gas mixed gas is performed by supplying a sterilizing gas supplied from a sterilizing gas source (not shown) for supplying the sterilizing gas and a dilution gas supply source (not shown). The gas for dilution supplied from) is mixed by using a mixer (not shown) or the like. At this time, it is preferable to adjust the concentration by controlling the flow rate control valve while monitoring the concentration with a concentration sensor. The dilution gas supply source can also serve as a replacement gas supply source. Furthermore, when introducing the sterilizing gas, a vacuum pump may be connected to the replacement gas discharge line 474, and the atmosphere control space 20 may be temporarily depressurized before introducing the sterilizing gas / dilution gas mixed gas. .

  After the atmosphere control space 20 has a gas atmosphere having a predetermined concentration of sterilizing gas, the surface to be sterilized from the ultraviolet irradiation means 50 disposed outside the atmosphere control space 20 and inside the body portion 42. Irradiate with UV rays to sterilize {(C) UV irradiation step}.

  After the sterilization is completed, the sterilizing gas / dilution gas mixed gas discharge line 473 of the gas discharge means 47 and the replacement gas introduction line 464 of the gas introduction means 46 are connected (communication), respectively, and the replacement gas dilution gas is supplied. The atmosphere control space 20 is replaced by introducing it into the atmosphere control space 20 and simultaneously discharging the sterilizing gas / dilution gas mixed gas contained in the atmosphere control space 20 {(D) sterilizing gas discharging step}. At this time, the sterilizing gas / diluent gas mixed gas discharged from the sterilizing gas / diluting gas mixed gas discharge line 473 is subjected to filter processing as necessary in whole or in part and supplied to the mixer. Recycled.

  The hat-type space determining member 40 may extend the space width defining portion 43 and share it with the plurality of hat-type space determining members 40. In defining the atmosphere control space 20, the hat-type space determining member 40 may be fixed and the container main body may be moved closer. FIG. 2 shows an example in which six hat-shaped space determining members 40 are arranged and arranged such that the space width defining portion 43 is shared and the body portion 42 is protruded upward. The upper stage is a top view (plan view), and the lower stage is a cross-sectional view. In this case, as indicated by a dotted line in the figure, the container main body 11 is moved close to the body 42 with the opening 12 facing downward to form the atmosphere control space 20.

  FIG. 3 shows an example using a cover type space defining member 40 '. FIG. 3 is a longitudinal sectional view when the atmosphere control space 20 is formed by the engagement of the cover type space determining member 40 ′ and the mounting surface 61, and the container main body accommodated in the atmosphere control space 20 is illustrated. A state in which the surface to be sterilized is irradiated with ultraviolet rays is shown.

  The cover-type space determining member 40 'has a bottomed cylindrical inner trunk portion 42' having one end opened and a bottom at the other end, and a bowl-shaped space width provided around the opening edge of the inner trunk portion. A cylindrical outer trunk portion 44 whose one end is sealed by the defining portion 43 ′ and the space width defining portion 43 ′ and whose other end is open, and a contact seal provided at the opening edge of the outer trunk portion 44 Part 45 '. The contact seal portion is not directly provided in the space width defining portion, but the contact seal portion 45 ′ is provided via the outer body portion 44, and the cover type space defining member 40 ′ and the container body 11 ( Except that the atmosphere control space 20 is formed by engaging with the placement surface 61 on which the container 10) is placed, and the container body 11 is accommodated in the atmosphere control space 20. Others are the same as FIG. The space width defining portion 43 ′ and the outer body portion 44 are preferably made of an ultraviolet shielding material such as metal, and the surface exposed to the atmosphere control space 20 of the space width defining portion 43 ′ is made of an ultraviolet reflecting material. It is preferred that Moreover, it is preferable that the cross section of inner side trunk | drum 42 'and the outer side trunk | drum 44 is similar to the shape of the container main body 11, respectively.

  The manufacturing method of the packaged food according to the present invention includes (I) a process of assembling the container body from the packaging container blanks, and (II) a process of sterilizing the inside of the container body by the sterilization method of the present invention, so as to be an industrial production process. [III] It is preferable to continuously perform the step of filling the inside of the container body sterilized with a liquid food such as a beverage and the step of [IV] sealing the opening of the container filled with the liquid food. .

  4 and 5 show schematic views of a continuous production system in which these steps [I] to [IV] are continuously performed.

  In FIG. 4, as a step [I], the flatly folded packaging container blanks 70 are formed into the shape of the container body 11 by a forming means (not shown), and then placed on a conveyance path 60 such as a conveyor. As the forming means, for example, known forming means such as the “forming means 2” described in Patent Document 1 can be used without any particular limitation. Thereafter, the container body 11 is sent to the sterilization yard, and is engaged with the space demarcating member 40 shown in FIG. 1 as step [II], and the steps (A), (B), (C) and (D) are carried out (Step IIa). After that, the container body 11 sterilized inside which is separated from the space demarcating member 40 moves along the conveyance path and is sent to the filling yard, and is filled with a filling 81 such as a beverage. For filling, a filling nozzle 80, a tank (not shown) for storing a filling 81 such as a beverage, a flow line (not shown) connecting the tank and the filling nozzle, a pump (not shown), and a lifter ( (Not shown) or the like can be used. After completion of the filling, the container body 11 filled with the filling 81 is moved along the conveyance path and sent to the seal yard, and the container body upper part using the sealing means 90 provided with a heater and a pressurizing device for heat sealing. The top seal portion provided in the is heat sealed. And the packaged food by which the liquid food was filled in the sealed container 10 is manufactured.

  In the continuous manufacturing system shown in FIG. 5, the space defining member 40 ′ shown in FIG. 2 is used in the step [II]. In this system, the container main body 11 placed on the conveyance path 60 in the step [I] is sent to the sterilization yard, where it is turned upside down and engaged with a space demarcating member 40 ′ provided outside the conveyance path. Then, steps (A), (B), (C) and (D) in the sterilization method of the present invention are carried out (step IIb). After the sterilization is finished, the sterilized container body 11 is separated from the space demarcating member 40 ′, turned upside down, and placed on the transport path 60 again. Then, it is sequentially conveyed to the filling yard and the seal yard, and the packaged food is manufactured in the same manner as in FIG.

  While the present invention has been described with reference to the drawings, the present invention is not limited to the embodiments shown in these drawings, and various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Container 11 ... Container main body 12 ... Opening of container main body 13 ... Surface to be sterilized 14 ... Internal side surface 15 ... Internal bottom surface 20 ... Atmosphere control space 30 ... Atmosphere Control space demarcating means 40, 40 '... space demarcating member 41 ... demarcating surface 42 ... body 42' ... inner body 43, 43 '... space width defining part 44 ... outer body 45 ... Contact seal 45 '... Contact seal 46 ... Gas introduction means 461 ... Gas introduction side partition valve 462 ... Gas introduction side line switching valve 463 ... Mixed gas introduction line 464 .. Replacement gas introduction line 47... Gas discharge means 471 .. Gas discharge side partition valve 472 .. Gas discharge side line switching valve 473 .. Sterilizing gas and dilution gas Mixed gas discharge line 47 ..Air / substitution gas discharge line 50 ... UV irradiation means 60 ... transport path 61 ... mounting surface 70 ... packaging container blanks 80 ... filling nozzle 81 ... filling 90 ..Sealing means

Claims (6)

A method of sterilizing a container having a bottomed cylindrical container body having an opening,
(A) An atmosphere control space defined by a defining surface and capable of holding gas existing in the inside thereof in an airtight or substantially airtight manner, wherein the volume of the space is smaller than the internal volume of the container body. A space defining step for defining a surface to be sterilized, which is an internally exposed surface of the container main body, in contact with a gas existing in the atmosphere control space using a space defining member having at least a part of the defining surface; ,
(B) a sterilizing gas introduction step of introducing a sterilizing gas into the atmosphere control space defined in the space defining step, and setting the atmosphere inside the atmosphere control space to an atmosphere of a predetermined concentration of sterilizing gas;
(C) an ultraviolet irradiation step of irradiating the surface to be sterilized which is in contact with the sterilizing gas having a predetermined concentration with ultraviolet rays;
(D) a sterilizing gas discharging step for discharging the sterilizing gas present in the atmosphere control space;
The sterilization method characterized by comprising.   The sterilization method according to claim 1, wherein at least part of the sterilizing gas discharged in the (D) sterilizing gas discharging step is reused in the (B) sterilizing gas introducing step. In the (A) space defining step,
The space-defining member is made of an ultraviolet light-transmitting material, has a bottomed cylindrical body having one end opened and a bottom at the other end, and a bowl-shaped space provided around the opening edge of the body. A space defining member having a width defining portion and an abutting seal portion provided in the space width defining portion, wherein the body portion can be inserted into the container body through the opening of the container body. ,
The atmosphere control space is defined such that the contact seal portion is brought into contact with the one end or the externally exposed surface of the container body, and the surface to be sterilized constitutes a part of the defined surface,
The method according to claim 1, wherein in the (C) ultraviolet irradiation step, ultraviolet irradiation is performed from outside the atmosphere control space. The method according to claim 1, wherein the container placed on the placement surface is sterilized with the opening of the container body facing upward.
In the (A) space defining step,
The space-defining member is made of an ultraviolet light transmissive material, has one end opened and a bottomed cylindrical inner body having a bottom at the other end, and a bowl-like shape provided around the opening edge of the inner body A space width defining portion, a cylindrical outer body portion whose one end is sealed by the space width defining portion and the other end is opened, and an abutting seal portion provided at an opening edge of the outer body portion, Using a space defining member that can accommodate the container body in a space between the outer body part and the inner body part,
By bringing the seal portion into contact with the mounting surface, the atmosphere control space is defined so that the container body is accommodated in the atmosphere control space.
The method according to claim 1, wherein in the (C) ultraviolet irradiation step, ultraviolet irradiation is performed from outside the atmosphere control space.   A method for producing a packaged food in which a food is filled and packaged in a container having a bottomed cylindrical container body having an opening, and the container is sterilized by the method according to any one of claims 1 to 4. Manufacturing the packaged food, comprising: a step of filling the container sterilized by the step, and a step of sealing the opening of the container filled with the food. Method. A sterilization apparatus for sterilizing a surface to be sterilized consisting of an exposed internal surface of a container body of a container having a bottomed cylindrical container body having an opening,
A space defined by a defining surface and capable of holding gas existing in the inside thereof in an airtight or substantially airtight manner, wherein the volume of the space is smaller than the inner volume of the container body. Atmosphere control space defining means;
Gas introduction means for introducing gas into the atmosphere control space;
Gas discharge means for discharging the gas in the atmosphere control space;
A bactericidal gas source for supplying bactericidal gas;
A replacement gas source for supplying a replacement gas consisting of sterilized inert gas or sterilized air;
Ultraviolet irradiation means,
The atmosphere control space defining means is (1) made of an ultraviolet light transmissive material, and has a cylindrical body with a bottom having one end opened and a bottom at the other end, and is provided around an opening edge of the body. A bowl-shaped space width defining portion and a contact seal portion provided in the space width defining portion, and the body portion can be inserted into the container body through the opening of the container body. A space-defining member, and the abutting seal portion is brought into contact with an externally exposed surface at or near the one end of the container body so that the surface to be sterilized constitutes a part of the defining surface. The atmosphere control space is defined, or (2) a bottomed cylindrical inner body made of an ultraviolet light transmissive material, having one end open and a bottom at the other end, and the inner body A flange-shaped space width defining portion provided around the opening edge of the portion, and one end is sealed by the space width defining portion. A cylindrical outer body having an opening at the other end, and an abutting seal provided at an opening edge of the outer body, and the space between the outer body and the inner body The container main body having a space demarcating member that can accommodate the container main body and placed on the placement surface with the opening of the container main body facing upward is applied with the contact seal portion against the placement surface. The atmosphere control space is demarcated so that the container main body is accommodated in the atmosphere control space by contacting the container body,
The ultraviolet irradiation means irradiates the surface to be sterilized, which is in contact with the gas existing inside the atmosphere control space, from outside the atmosphere control space,
A sterilizer characterized by that.

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