Food sterilization apparatus and food sterilization method

Abstract

To provide a food sterilization apparatus and method that can sterilize the surface of food in a short time while suppressing the enlargement of equipment and reducing the energy required for generating superheated steam.SOLUTION: A food sterilization apparatus that sterilizes food (F) by jetting superheated steam toward the food, the apparatus comprising a conveying means (17) for conveying food placed on a placement surface, and jetting means (21, 31, 41, 51) for jetting superheated steam toward the food conveyed by the conveying means, wherein the jetting means jets the superheated steam as a planar superheated steam flow, and the food placed on the placement surface is conveyed by the conveying means so as to traverse the planar superheated steam flow from one planar side to the other planar side. A food sterilization method using the food sterilization apparatus is also provided.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a food sterilization apparatus and a food sterilization method. [Background technology]

[0002] Conventionally, the following food sterilization devices and food sterilization methods have been known.

[0003] Patent Document 1 describes a method for heat sterilization of granular materials, in which granular materials such as vegetable pieces, breadcrumbs, curry powder, etc. are brought into contact with superheated steam in a pipe line and sterilized while being transported.

[0004] Patent Document 2 describes a method and device for sterilizing fresh vegetables using superheated steam. In this device, superheated steam is sprayed from above and below fresh vegetables being transported on a conveyor to sterilize the vegetables. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 1-20859 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-33202 Summary of the Invention [Problem to be solved by the invention]

[0006] As in the method for heat sterilization of granular materials described in Patent Document 1, sterilization is generally carried out by bringing superheated steam into contact with food containing granular materials and the like.

[0007] In addition, a technique for sterilizing the surface of food such as fresh vegetables transported by a conveyor by injecting superheated steam into the food and bringing the food into contact with the food, such as a method and apparatus for sterilizing fresh vegetables using superheated steam, is also commonly used, as described in Patent Document 2.

[0008] The invention described in Patent Document 2 addresses the problem of food such as fresh vegetables deteriorating when brought into contact with superheated steam for sterilization, by contacting the food with superheated steam for a short period of time, for example, one second, and then cooling the food with cooling water to prevent deterioration.

[0009] However, if one wishes to sterilize the surface of food such as fresh vegetables in such a short time, it is necessary to instantaneously inject a large amount of superheated steam sufficient to envelop the food being transported on the conveyor.

[0010] In such cases, the energy required to heat saturated steam to superheated steam increases, and in addition to the equipment required to heat a large amount of saturated steam to superheated steam, it is also necessary to provide piping and nozzles capable of injecting superheated steam at a high flow rate, which increases the size of the equipment.

[0011] In particular, when the food whose surface is to be sterilized with superheated steam is fresh vegetables or other foods that are easily deteriorated by heating, a cooling system using cooling water is also required to keep the heating time short, which further increases the size of the equipment.

[0012] The present invention aims to provide a food sterilization device and a food sterilization method that can sterilize the surface of food in a short time while suppressing the increase in size of the equipment and saving energy for generating superheated steam. [Means for solving the problem]

[0013] In order to achieve the above object, the food sterilization device according to the present invention comprises: A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; an injection means for injecting superheated steam toward the food being conveyed by the conveying means; Equipped with the injection means injects the superheated steam as a planar superheated steam flow, The food placed on the placing surface is transported by the transporting means so as to cross the planar superheated steam flow from one side to the other side of the surface.

[0014] In addition, the food sterilization apparatus according to the present invention is A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; a plurality of spraying means for spraying superheated steam toward the food being conveyed by the conveying means; Equipped with The plurality of spraying means are characterized in that they spray superheated steam so as to concentrate on the food placed on the placement surface.

[0015] The food sterilization method according to the present invention further comprises: A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; A planar superheated steam flow is sprayed toward the food being conveyed, The food placed on the placement surface is transported across the planar superheated steam flow from one side to the other side of the surface.

[0016] The food sterilization method according to the present invention further comprises: A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; The method is characterized in that superheated steam flows are sprayed from multiple directions toward the food being conveyed so as to be concentrated. [Effects of the Invention]

[0017] According to the food sterilization apparatus and food sterilization method of the present invention, it is possible to sterilize the surface of food in a short time while suppressing an increase in the size of the equipment and saving energy for generating superheated steam. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a block diagram showing the overall configuration of a food sterilization apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view showing the overall configuration of the food sterilization apparatus. [Figure 3] FIG. 2 is a perspective view showing the overall configuration of the food sterilization apparatus omitting the housing and the like. [Figure 4] 1A and 1B show the overall configuration of the food sterilization device omitting the housing and other components, where (a) is a front view omitting the wall surface, and (b) is a left side view omitting the wall surface. [Figure 5] 3A and 3B show the configuration of the first upper injection section and the second upper injection section of the food sterilization device, where (a) is a perspective view, (b) is a cross-sectional view taken along line BB in (a), and (c) is an enlarged view of the cross-section taken along line CC in (a). [Figure 6] 1A and 1B show the configuration of the first lower injection section and the second lower injection section of the food sterilization device, where (a) is an oblique view, (b) is a DD cross-sectional view of (a), and (c) is an enlarged EE cross-sectional view of (a). [Figure 7] 4(b) is an enlarged view of a main part of the cross section taken along the line AA in FIG. 4(b) showing an example of a predetermined position of food. [Figure 8] FIG. 2 is a step diagram of a food sterilization method using the food sterilization device. DETAILED DESCRIPTION OF THE INVENTION

[0019] The first invention is A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; an injection means for injecting superheated steam toward the food being conveyed by the conveying means; Equipped with the injection means injects the superheated steam as a planar superheated steam flow, The food sterilization device is characterized in that the food placed on the placing surface is transported by the transport means so as to cross the planar superheated steam flow from one side to the other side of the surface.

[0020] In this way, by spraying superheated steam as a planar superheated steam flow and passing the food from one side to the other side of the planar superheated steam flow, the temperature near the surface of the food, particularly in the localized area where the superheated steam is concentrated, can be raised to a high temperature in a short time, thereby sterilizing the surface of the food. In addition, if the food to be sterilized is fresh vegetables or the like that will deteriorate when heated, the temperature can be lowered in a short time, preventing deterioration of the food.

[0021] Furthermore, the food sterilization apparatus can sterilize the surface of food in a short time while suppressing the increase in size of the sterilization equipment and saving energy for generating superheated steam.

[0022] The second invention is the first invention, The spraying means is a food sterilization device characterized by having a spray nozzle that sprays the superheated steam as a planar superheated steam flow by passing the superheated steam through a gap between flat surfaces spaced at a predetermined interval.

[0023] This makes it easy to cause the injection means to inject a planar flow of superheated steam.

[0024] The third invention is the second invention, The injection means is A pipe through which superheated steam is introduced; a pair of strip-shaped members arranged parallel to each other at a predetermined interval in a long hole formed in a pipe wall in the pipe length direction, The food sterilization device is characterized in that the pair of belt-shaped members form a gap between flat surfaces spaced at a predetermined interval to allow superheated steam to pass through.

[0025] This makes it possible to easily configure the injection means capable of injecting a planar flow of superheated steam.

[0026] The fourth invention is the first invention, The food sterilization device is characterized in that a plurality of injection means are provided, and the planar superheated steam flow injected from each injection means is injected so as to be concentrated on the food being transported by the transport means.

[0027] This allows the superheated steam flow to be more concentrated on the food, thereby effectively sterilizing the food.

[0028] The fifth invention is the fourth invention, The food sterilization device is characterized in that the injection means is arranged upstream and downstream in the conveying direction of the food being conveyed by the conveying means from a predetermined position where the superheated steam flow is injected so as to be concentrated.

[0029] This makes it easy to concentrate the superheated steam on the front or rear side of the food in the direction of conveyance by the conveying means, thereby sterilizing the food.

[0030] The sixth invention is the fourth invention, The conveying means has an opening through which the superheated steam can pass, The spraying means are arranged above and below the loading surface of the conveying means, and are a food sterilization device characterized by spraying superheated steam from above and below toward the food being conveyed by the conveying means.

[0031] This makes it easy to concentrate the superheated steam on the upper and lower surfaces of the food to sterilize it.

[0032] The seventh invention is any one of the first to sixth inventions, The food sterilization device is characterized in that the spraying means is capable of varying the angle that the planar superheated steam flow makes with the placement surface of the conveying means.

[0033] This makes it possible to change the angle of the superheated steam sprayed from the spray means depending on the shape of the food being transported to a predetermined position by the transport means, making it possible to sterilize a variety of foods.

[0034] The eighth invention is A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; a plurality of spraying means for spraying superheated steam toward the food being conveyed by the conveying means; Equipped with The food sterilizer is characterized in that the plurality of spraying means spray superheated steam so as to concentrate the sprayed superheated steam on the food placed on the placing surface.

[0035] This allows food to be effectively sterilized by the superheated steam injected from the multiple injection means, and provides a food sterilization apparatus that can sterilize the surface of food in a short time while suppressing an increase in the size of the sterilization equipment and saving energy for generating superheated steam.

[0036] The ninth invention is A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; A planar superheated steam flow is sprayed toward the food being conveyed, The food sterilization method is characterized in that the food placed on the placement surface is conveyed across the planar superheated steam flow from one side to the other side of the surface.

[0037] In this way, by spraying superheated steam as a planar superheated steam flow and passing the food from one side to the other side of the planar superheated steam flow, the temperature near the surface of the food, particularly in the localized area where the superheated steam is concentrated, can be raised to a high temperature in a short time, thereby sterilizing the surface of the food. In addition, if the food to be sterilized is fresh vegetables or the like that will deteriorate when heated, the temperature can be lowered in a short time, preventing deterioration of the food.

[0038] Furthermore, the food sterilization apparatus can sterilize the surface of food in a short time while suppressing the increase in size of the sterilization equipment and saving energy for generating superheated steam.

[0039] A tenth aspect of the present invention is the ninth aspect of the present invention, This is a food sterilization method characterized in that a planar flow of superheated steam is sprayed from multiple directions so as to be concentrated onto food being conveyed by a conveying means.

[0040] This allows the superheated steam flow to be more concentrated on the food, thereby effectively sterilizing the food.

[0041] An eleventh aspect of the present invention is the tenth aspect of the present invention, This is a food sterilization method characterized in that a planar flow of superheated steam is sprayed onto the food from both the upstream and downstream sides in the direction of food transport so as to be concentrated on the food.

[0042] This makes it easy to concentrate the superheated steam on the front or rear side of the food in the direction of conveyance by the conveying means, thereby sterilizing the food.

[0043] A twelfth aspect of the present invention is the tenth aspect of the present invention, This is a food sterilization method characterized in that a planar flow of superheated steam is sprayed onto the food from above and below in the direction of food transport so as to be concentrated on the food.

[0044] This makes it easy to concentrate the superheated steam on the upper and lower surfaces of the food to sterilize it.

[0045] The thirteenth invention is A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; The food sterilization method is characterized in that superheated steam flows are sprayed from a plurality of directions toward the food being conveyed so as to be concentrated.

[0046] This allows food to be effectively sterilized by superheated steam sprayed from multiple directions, and provides a food sterilization device that can sterilize the surface of food in a short time while suppressing the increase in size of the sterilization equipment and saving energy for generating superheated steam.

[0047] (Embodiment 1) (Configuration of food sterilization equipment) First, the basic configuration of the food sterilization apparatus 1 of the present invention will be described.

[0048] As shown in Figures 1, 2 and 3, the food sterilization apparatus 1 includes: a main body 10 in which a housing 11 and a net conveyor (transport means) 17 are attached to a frame 15, which is a framework; a superheated steam supply unit (20) that sprays superheated steam (H) onto food (F) within the housing (11) of the main body (10); a superheated steam generating unit (60) that generates superheated steam (H) to be supplied to the superheated steam supply unit (20); a control unit 70 for controlling the equipment and receiving signals from various sensors; It consists of:

[0049] In FIG. 1, the dashed lines indicate the flow of saturated steam V and superheated steam H flowing in the pipe 63, and the broken lines indicate the connection of electric communication lines or electric signal lines.

[0050] (Main body) As shown in FIGS. 2, 3, and 4(a) and (b), the main body 10 includes: a housing 11 that forms the outer shell of a frame 15, which is a framework, and has an opening 12 at the top; a net conveyor 17 that conveys food F placed on the placement surface from an inlet 13, which is an opening on the side of the housing 11, to an outlet 14; Two wall surfaces 16 are provided on both sides of the net conveyor 17 in a direction perpendicular to the conveying direction of the food F so as to sandwich the net conveyor 17 within the housing 11; It consists of:

[0051] An opening 12 at the top of the housing 11 is connected to a duct leading to the ventilation equipment of the facility. By operating the ventilation equipment of the facility, the superheated steam H injected inside the housing 11 can be exhausted to the outside of the facility, for example, into the atmosphere.

[0052] The net conveyor 17 has a plurality of openings on the placement surface on which the food F is placed. The plurality of openings allow the superheated steam H sprayed from above the placement surface to pass below the placement surface, and allow the superheated steam H sprayed from below the placement surface to pass above the placement surface.

[0053] 2, 3, and 4(a) and (b) show only the outgoing side of the net conveyor 17 for ease of viewing. In reality, there is a return side (not shown), and the net conveyor 17 is configured to be endless.

[0054] (Superheated steam supply section) As shown in FIG. 4(a), the superheated steam supply unit 20 a first upper injection section (injection means) 21 and a second upper injection section (injection means) 31 positioned above the loading surface of the net conveyor 17 and injecting superheated steam H toward the food F from injection ports 25, 35; a first lower injection section (injection means) 41 and a second lower injection section (injection means) 51 located below the loading surface of the net conveyor 17 and injecting superheated steam H toward the food F from injection ports 45, 55; It consists of:

[0055] As shown in FIGS. 3, 4(a)(b), 5(a)(b)(c), and 7, the first upper injection section 21 and the second upper injection section 31 are Pipes 22, 32 made of steel pipes, for example, seamless pipes made of SUS304; Two strip-shaped members 23, 33 sandwiching a plurality of opening adjustment members 24, 34, inserted into long holes opened in the pipe length direction of the pipes 22, 32, and joined by welding or the like; injection ports 25, 35 formed by two strip-shaped members 23, 33 and a plurality of opening adjustment members 24, 34 sandwiched therebetween; Valves 26, 36 are provided in a pipe 63 connected to the pipes 22, 32, and adjust the flow rate of the superheated steam H supplied to the injection ports 25, 35 by adjusting the opening degree thereof; Rotation means 27, 37, which are swivel joints provided in a pipe 63 connected to the pipes 22, 32 via a flange, for enabling the pipes 22, 32 to rotate relative to the pipe 63; It consists of:

[0056] The above-mentioned multiple opening adjustment materials 24, 34 form gaps between flat surfaces spaced a predetermined distance apart between the strip-shaped members 23, 33, thereby allowing the first upper injection section 21 and the second upper injection section 31 to convert the superheated steam H into a planar superheated steam flow and inject it from above downward.

[0057] Furthermore, as shown in FIGS. 3, 4(a)(b), 6(a)(b)(c), and 7, the first lower injection part 41 and the second lower injection part 51 are Piping 42, 52 made of steel pipes, for example, seamless pipes made of SUS304; Two strip-shaped members 43, 53 sandwiching a plurality of opening adjustment members 44, 54, inserted into long holes opened in the pipe length direction of the pipes 42, 52, and joined by welding or the like; Injection ports 45, 55 formed by two strip-shaped members 43, 53 and a plurality of opening adjustment members 44, 54 sandwiched therebetween; Valves 46, 56 are provided in a pipe 63 connected to the pipes 42, 52, and adjust the flow rate of the superheated steam H supplied to the injection ports 45, 55 by adjusting the opening degree thereof; Rotation means 47, 57, which are swivel joints provided in a pipe line 63 connected to the pipes 42, 52 via a flange, for enabling the pipes 42, 52 to rotate relative to the pipe line 63; It consists of:

[0058] The multiple opening adjustment materials 44, 54 form gaps between flat surfaces spaced a predetermined distance apart between the strip-shaped members 43, 53, allowing the first lower injection section 41 and the second lower injection section 51 to spray the superheated steam H in a planar superheated steam flow from below upward.

[0059] 5 and 6, the opening adjustment materials 24, 34, 44, 54 sandwiched between the belt-shaped members 23, 33, 43, 53 are shown by hatching to make them stand out. In reality, the opening adjustment materials 24, 34, 44, 54 are sandwiched between the belt-shaped members 23, 33, 43, 53 and cannot be seen from the outside unless one looks into the injection ports 25, 35, 45, 55.

[0060] The first upper injection section 21, second upper injection section 31, first lower injection section 41 and second lower injection section 51 are respectively arranged so that the pipe length direction of the piping 22, 32, 42, 52 extends in the width direction of the net conveyor 17, i.e., in a direction perpendicular to the conveying direction within a plane parallel to the placement surface. The piping 22, 32, 42, 52 is made rotatable by the rotating means 27, 37, 47, 57, so that the angle that the planar superheated steam flow forms with the placement surface of the net conveyor 17 can be changed.

[0061] 7, the first upper injection unit 21 and the first lower injection unit 41 are configured to be located upstream of the food F when the food F placed on the placement surface of the net conveyor 17 is located at a predetermined position P. The second upper injection unit 31 and the second lower injection unit 51 are configured to be located downstream of the food F when the food F placed on the placement surface of the net conveyor 17 is located at the predetermined position P.

[0062] The injection ports 25, 35, 45, 55 are gaps sandwiched between smooth strip-shaped members 23, 33, 43, 53 that extend from the pipes 22, 32, 42, 52 in a direction perpendicular to the pipe length direction of the pipes 22, 32, 42, 52. Therefore, the superheated steam H injected from the injection ports 25, 35, 45, 55 is injected so as to travel straight in a plane at a predetermined flow velocity for a distance according to its temperature and pressure.

[0063] (Superheated steam generation section) As shown in FIG. 1, the superheated steam generating unit 60 includes: a boiler 61 that heats water to generate saturated steam V; A heating means 62 for heating saturated steam V generated in a boiler 61 to generate superheated steam H; A pipe line 63 which is a steel pipe connecting the boiler 61, the heating means 62, etc. It consists of:

[0064] The pipeline 63 is preferably provided with a flowmeter for measuring the flow rate of the saturated steam V or superheated steam H flowing through the pipeline 63, a pressure gauge for measuring the pressure thereof, and a thermometer for measuring the temperature thereof. Naturally, the pipeline 63 is also preferably provided with a drain pocket, a steam trap, etc.

[0065] (Control unit) 1, the control unit 70 is electrically connected to the devices and various sensors provided in the main body 10, the superheated steam supply unit 20, and the superheated steam generation unit 60, and controls the devices and receives signals from the various sensors. Note that the connection with the control unit 70 may be wired or wireless.

[0066] (Food sterilization method) Next, a food sterilization method performed by the food sterilization apparatus 1 will be described.

[0067] As shown in Figure 8, the food sterilization method is as follows: an adjustment step S100 of adjusting angles of the jet ports 25, 35, 45, 55 of the first upper jetting portion 21, the second upper jetting portion 31, the first lower jetting portion 41, and the second lower jetting portion 51 relative to a horizontal plane; a preparation step S200 in which saturated steam V generated in a boiler 61 is heated by a heating means 62 to generate superheated steam H; a conveying step S300 in which food F to be sterilized is placed on the placement surface of the net conveyor 17 and conveyed; an injection step S400 in which superheated steam H is injected onto the food F conveyed in the conveying step S300 to sterilize the surface of the food F; a removal step S500 in which the food F, the surface of which has been sterilized in the spraying step S400, is removed from the net conveyor 17; It consists of:

[0068] (Adjustment steps) The first adjustment step S100 will be described.

[0069] 3, the pipes 22, 32, 42, 52 of the first upper injection section 21 and the second upper injection section 31 and the first lower injection section 41 and the second lower injection section 51 are connected to a pipeline 63 via rotating means 27, 37, 47, 57. Therefore, an operator can manually rotate the pipes 22, 32, 42, 52 in the circumferential direction to change the angles of the injection ports 25, 35, 45, 55 with respect to the horizontal plane.

[0070] 7, the nozzle 25 of the first upper jetting section 21 is tilted downward at a predetermined angle θ1, for example, 50 degrees counterclockwise, with respect to the horizontal plane by a rotation means 27 attached to the connection between the pipe 22 and the conduit 63. The nozzle 35 of the second upper jetting section 31 is tilted downward at a predetermined angle θ2, for example, 35 degrees clockwise, with respect to the horizontal plane.

[0071] Furthermore, the nozzle 45 of the first lower jetting part 41 is inclined upward at a predetermined angle θ3, for example, 45 degrees clockwise, relative to the horizontal plane, and the nozzle 55 of the second lower jetting part 51 is inclined upward at a predetermined angle θ4, for example, 60 degrees counterclockwise, relative to the horizontal plane.

[0072] This allows the superheated steam H sprayed from the nozzles 25, 35 of the first upper spray section 21 and the second upper spray section 31 and the superheated steam H sprayed from the nozzles 45, 55 of the first lower spray section 41 and the second lower spray section 51 to be adjusted so that they come into concentrated contact simultaneously when the food F being transported by the net conveyor 17 is positioned at a predetermined position P.

[0073] (Preparation step) The preparation step S200 performed after the adjustment step S100 will now be described.

[0074] Saturated steam V generated by heating water in a boiler 61 shown in Fig. 1 is heated by a heating means 62. As a result, superheated steam H is generated and sent through a pipe 63 to the first upper injection part 21 and the second upper injection part 31, and the first lower injection part 41 and the second lower injection part 51 that constitute the superheated steam supply part 20.

[0075] (Transport step) The transport step S300, which follows the preparation step S200, will now be described.

[0076] First, the net conveyor 17 shown in Figure 2 is driven by operating the control unit 70. Then, food F is placed on the placement surface of the net conveyor 17 on the carry-in entrance 13 side, and the food F is carried into the housing 11 through the carry-in entrance 13.

[0077] (Injection step) The ejection step S400, which follows the transfer step S300, will now be described.

[0078] As shown in Figure 7, superheated steam H is simultaneously and intensively sprayed onto food F transported to a predetermined position P by a net conveyor 17 from the first upper spray section 21 and the second upper spray section 31, and the first lower spray section 41 and the second lower spray section 51.

[0079] As a result, superheated steam H can be sprayed from the upstream and downstream sides of food F located at a predetermined position P, and the superheated steam H can be concentrated locally on the surface of the food F located at the predetermined position P for sterilization. Therefore, there is no need to spray superheated steam H at a large flow rate so as to contact the entire surface of the food F, and there is no need to provide a large nozzle or the like inside the sterilization device.

[0080] In addition, since there is no need to inject the superheated steam H at a large flow rate using such a large nozzle, the energy required to generate the superheated steam H can be saved.

[0081] Furthermore, by injecting superheated steam H simultaneously from the upstream and downstream sides in a concentrated manner onto food F located at a predetermined position P, or in particular by providing strip-shaped members 23, 33, 43, 53 spaced at a predetermined interval and passing superheated steam H through the gaps between the flat surfaces, the superheated steam H can be injected as a planar superheated steam flow, and the food F can be passed from one side of the planar superheated steam flow to the other side, thereby concentrating the superheated steam H locally on the surface of the food F and sterilizing it.

[0082] Furthermore, since the superheated steam H is concentrated locally on the surface of the food F to sterilize it, the food F is less likely to be heated to its interior, and after the superheated steam H has been sprayed, the temperature of the food F can be reduced to near room temperature in a short period of time, for example, approximately 1 to 2 minutes.For example, if the room temperature is 20°C, the overall temperature of the food F can be reduced to approximately 20°C to 30°C.

[0083] This makes it possible to prevent food F from deteriorating due to heating, such as fresh vegetables, if the food F is food F that is easily degraded by heating, and to sterilize the surface of such food F without affecting the texture or color of the fresh vegetables.

[0084] Furthermore, if the food F whose surface is to be sterilized by superheated steam H is food F such as fresh vegetables that are easily deteriorated by heating, the configuration for supplying cooling water required to shorten the heating time of the food F is not required, and the equipment can be made smaller.

[0085] Furthermore, the two wall surfaces 16 arranged to sandwich the net conveyor 17 can prevent the superheated steam H immediately after being sprayed from the first upper spray portion 21 and the second upper spray portion 31 and the first lower spray portion 41 and the second lower spray portion 51 from coming into contact with components inside the housing 11, causing the components to malfunction due to heat, or being damaged by expansion or contraction after expansion. The superheated steam H can also be quickly made to flow to the opening 12 at the top of the housing 11 and be exhausted.

[0086] (Removal step) The removal step S500, which follows the injection step S400, will now be described.

[0087] As shown in FIG. 2, food F is carried out from housing 11 by net conveyor 17 through carry-out opening 14 and is then removed by an operator.

[0088] The food sterilization method using food sterilization apparatus 1 is carried out by carrying out the steps described above.

[0089] (Other matters) In addition, a sensor for measuring the temperature and humidity inside the housing 11 may be provided inside the housing 11 provided in the food sterilization apparatus 1 of this embodiment.

[0090] In addition, the rotation means 27, 37, 47, 57 may be configured as a loose flange or the like that rotatably fixes the pipes 22, 32, 42, 52 to the flange, other than a swivel joint, or the angle may be adjusted by the amount of screwing when screwing the pipes 22, 32, 42, 52 into the flange to fix them.

[0091] In addition, the piping 22, 32, 42, 52 between the first upper injection section 21 and the second upper injection section 31 and the first lower injection section 41 and the second lower injection section 51 may be provided with a fixing member to maintain the rotation angle of the piping 22, 32, 42, 52 after being rotated in the adjustment step S100, such as a clip that stops the rotation by clamping.

[0092] Here, the rotation angles of pipes 22, 32, 42, 52 are not limited to those that are adjusted when food sterilization apparatus 1 is used, but may be adjusted when the apparatus is manufactured, or may be manufactured to be fixed in advance.

[0093] Although the pipes 22, 32, 42, 52 connecting the first upper injection part 21 and the second upper injection part 31 to the first lower injection part 41 and the second lower injection part 51 are described as being rotated manually by an operator, they may also be rotated automatically by combining a driving means such as a stepping motor. This allows the angles of the pipes 22, 32, 42, 52 to be precisely controlled, and the direction of the superheated steam H injected from the injection ports 25, 35, 45, 55 to be as intended.

[0094] Furthermore, by automatically rotating the nozzles, nozzle 25 of first upper spray unit 21 and nozzle 35 of second upper spray unit 31, and nozzle 45 of first lower spray unit 41 and nozzle 55 of second lower spray unit 51 can be rotated to an angle corresponding to the food F to be sterilized. Furthermore, by incorporating each rotation angle into a program, the food F can be input into control unit 70, and the angle of each nozzle 25, 35, 45, 55 can be rotated to an angle corresponding to the food F to be sterilized. This makes it possible to make the device suitable for sterilizing a wider variety of foods F.

[0095] Note that the predetermined angles θ1, θ2, θ3, and θ4 formed by the first upper injection section 21 and the second upper injection section 31 and the first lower injection section 41 and the second lower injection section 51 with respect to the horizontal plane described in this embodiment are merely examples. For example, when the predetermined angle θ1, etc. is set to 90°, that is, when superheated steam H is injected vertically, the superheated steam H can be concentrated mainly on the upper and lower surfaces of the food F. Furthermore, by setting various angles, the superheated steam H can be concentrated mainly on the front and rear sides of the food F in the direction of transport by the net conveyor 17.

[0096] In addition, the angle can be set so that only the superheated steam H sprayed from the spray nozzles 25, 35 of the first upper spray section 21 and the second upper spray section 31 contacts the food F being transported by the net conveyor 17 in a concentrated manner at the same time when the food F is positioned at a predetermined position P.

[0097] This allows superheated steam H to be sprayed from the upstream and downstream sides onto the upper side of food F located at a predetermined position P, effectively sterilizing the surface of the food F. This is beneficial in cases where there is no need to spray superheated steam H onto the lower side of food F, or where spraying superheated steam H would cause problems on the lower side of food F, such as deterioration due to heat.

[0098] In addition, the angle can be set so that only the superheated steam H sprayed from the spray ports 45, 55 of the first lower spray section 41 and the second lower spray section 51 contacts the food F being transported by the net conveyor 17 in a concentrated manner at the same time when the food F is positioned at a predetermined position P.

[0099] This allows superheated steam H to be sprayed from the upstream and downstream sides onto the lower side of food F located at a predetermined position P, effectively sterilizing the surface of the food F. This is beneficial when there is no need to spray superheated steam H onto the upper side of food F, or when spraying superheated steam H would cause problems on the upper side of food F, such as deterioration due to heat.

[0100] Furthermore, in addition to the first upper injection section 21 and the second upper injection section 31, more upper injection sections such as a third upper injection section and a fourth upper injection section may be provided, and the superheated steam H sprayed from the injection port of each upper injection section may be configured to come into concentrated contact with the food F at the same position as the predetermined position P where the superheated steam H sprayed from the first upper injection section 21 and the second upper injection section 31, or the first lower injection section 41 and the second lower injection section 51 comes into concentrated contact with the food F, or at another position.

[0101] Furthermore, the apparatus may be configured to have more lower injection sections, such as a third lower injection section and a fourth lower injection section, so that the superheated steam H injected from the injection ports of each lower injection section comes into concentrated contact with the food F at the same position as the predetermined position P where the superheated steam H injected from the first upper injection section 21 and the second upper injection section 31, or the first lower injection section 41 and the second lower injection section 51 comes into concentrated contact with the food F, or at another position.

[0102] Furthermore, the position where the superheated steam H is concentrated on the food F by the upper injection section and the position where the superheated steam H is concentrated on the food F by the lower injection section do not necessarily have to be the same, and the superheated steam H may be concentrated on the food F sequentially from above or below as it is transported by the net conveyor 17.

[0103] This allows for multiple predetermined positions P where superheated steam H comes into concentrated contact with food F being transported by the net conveyor 17, making it possible to create a food sterilization device 1 that can perform a variety of sterilization methods tailored to the food F.

[0104] Furthermore, the number of upper and lower injection portions is not limited to a plurality, but may be one of each, or only one of either.

[0105] The timing for spraying superheated steam H from first upper spray unit 21 and second upper spray unit 31 and first lower spray unit 41 and second lower spray unit 51 may be determined as appropriate. For example, an operator may manually open valves 26, 36, 46, and 56 to spray superheated steam H according to the position of food F being conveyed by conveying means within housing 11.

[0106] Also, at the same time as starting the conveying step S300, the valves 26, 36, 46, and 56 may be opened to spray the superheated steam H. Furthermore, a photoelectric sensor may be attached inside the housing 11 to detect that the food F has been carried in through the carry-in entrance 13 by the net conveyor 17, and when the control unit 70 receives that signal, the solenoid valves 26, 36, 46, and 56 may be opened to spray the superheated steam H.

[0107] Furthermore, a plurality of upper injection sections and a plurality of lower injection sections may be provided, and superheated steam H may be injected from only one or more of them during use. Even when a plurality of upper injection sections and a plurality of lower injection sections are provided, it is not necessary that each of them injects superheated steam H toward the same location on the food F, and each of them may inject superheated steam H toward different locations on the food F.

[0108] Note that functional water, such as hypochlorous acid water, which exhibits a sterilizing effect may be mixed into the superheated steam H that is sprayed toward the food F. Using a mixing device such as an ejector, the functional water can be mixed into the saturated steam V or superheated steam H flowing through the pipeline 63, and then sprayed together with the superheated steam H. This adds the effect of the functional water to the sterilizing effect of the superheated steam H, making it possible to sterilize the surface of the food F in a shorter time.

[0109] It should be noted that the present invention can be realized by appropriately combining the contents described in the embodiments and modifications. [Explanation of symbols]

[0110] 1 Food sterilizer 10 Main body 11. Housing 12 aperture 13 Loading entrance 14 Exit 15 frames 16 Wall 17 Net conveyor (transport means) 20 Superheated steam supply section 21 First upper injection section (injection means) 22 Piping 23 Belt-shaped member 24 Aperture adjustment material 25 Nozzle 26 Valves 27 Rotation means 31 Second upper injection section (injection means) 32 Piping 33 Belt-shaped member 34 Aperture adjustment material 35 Nozzle 36 Valves 37 Rotation means 41 First lower injection section (injection means) 42 Piping 43 Belt-shaped member 44 Aperture adjustment material 45 Nozzle 46 Valve 47 Rotation means 51 Second lower injection section (injection means) 52 Piping 53 Belt-shaped member 54 Aperture adjustment material 55 Nozzle 56 Valve 57 Rotation means 60 Superheated steam generator 61 Boiler 62 Heating means 63 Pipeline 70 Control Unit F Food H Superheated steam P designated position V saturated water vapor θ1~4 specified angles S100 Adjustment Step S200 Preparation Steps S300 Transport Step S400 injection step S500 Removal Step

Claims

1. A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; an injection means for injecting superheated steam toward the food being conveyed by the conveying means; Equipped with the injection means injects the superheated steam as a planar superheated steam flow, A food sterilization apparatus characterized in that food placed on the placement surface is transported by the transport means so as to cross the planar superheated steam flow from one side to the other side of the surface.

2. 2. The food sterilizer according to claim 1, wherein the injection means has an injection port that passes the superheated steam through a gap between the flat surfaces spaced at a predetermined interval, thereby forming the superheated steam into a planar superheated steam flow and injecting it.

3. The injection means is A pipe through which superheated steam is introduced; a pair of strip-shaped members arranged parallel to each other at a predetermined interval in a long hole formed in a wall of the pipe in the pipe length direction, 3. The food sterilizer according to claim 2, wherein the pair of belt-shaped members form a gap between flat surfaces spaced apart by a predetermined distance to allow superheated steam to pass through.

4. 2. The food sterilizer according to claim 1, wherein a plurality of injection means are provided, and the planar superheated steam flow injected from each injection means is injected so as to be concentrated on the food being transported by the transport means.

5. 5. The food sterilization apparatus according to claim 4, wherein the injection means is arranged upstream and downstream in the conveying direction of the food being conveyed by the conveying means from a predetermined position where the superheated steam flow is injected so as to concentrate the superheated steam flow.

6. The conveying means has an opening through which the superheated steam can pass, 5. The food sterilization apparatus according to claim 4, wherein the spraying means are arranged above and below the loading surface of the conveying means, and spray superheated steam from above and below toward the food being conveyed by the conveying means.

7. 7. The food sterilizer according to claim 1, wherein the spraying means is capable of varying the angle that the planar superheated steam flow makes with the placement surface of the conveying means.

8. A food sterilizer that sprays superheated steam toward food to sterilize it, a conveying means for conveying food placed on the placement surface; a plurality of spraying means for spraying superheated steam toward the food being conveyed by the conveying means; Equipped with The food sterilizer is characterized in that the plurality of spraying means spray superheated steam so as to concentrate the sprayed superheated steam on the food placed on the placing surface.

9. A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; A planar superheated steam flow is sprayed toward the food being conveyed, A food sterilization method comprising conveying food placed on the placement surface across the planar superheated steam flow from one side to the other side of the surface.

10. 10. The food sterilization method according to claim 9, wherein the planar superheated steam stream is sprayed from a plurality of directions so as to be concentrated onto the food being conveyed by the conveying means.

11. 11. The method for sterilizing food according to claim 10, wherein the planar superheated steam flow is sprayed onto the food from both the upstream side and the downstream side in the direction of food transport so as to be concentrated on the food.

12. 11. The method for sterilizing food according to claim 10, wherein the planar superheated steam streams are sprayed onto the food from above and below in the direction of food transport so as to be concentrated on the food.

13. A food sterilization method for sterilizing food by injecting superheated steam toward the food, The food is placed on the placement surface of the conveying means and conveyed; A food sterilization method comprising injecting superheated steam streams from multiple directions toward the food being conveyed in a concentrated manner.

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