JP2696226B2 - Sterilization method of packaged food - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sterilization method for heating and sterilizing food stored in a packaging container so that the food can be stored for a long period of time.

(Prior Art) Conventionally, in the case of foods such as processed cereals (raw or boiled udon, spaghetti, and cooked rice), a method of heat sterilization has been used in order to enhance the shelf life and improve the shelf life.

As one means of this heat sterilization, a sealed heat sterilization called a retort method is known, but in a tray type container, residual air cannot be avoided, and this residual air expands in the container when heated. For this reason, there is a problem that the container is deformed or the seal becomes defective. Further, since the retort method is processed at a relatively high temperature, in the case of processed grains, there is also a problem that browning occurs and the food quality is reduced. Therefore, it is difficult to perform retort type heat sterilization on a tray type container. For this reason, a method has been proposed in which a through hole is formed in a part of a tray-type container (Japanese Patent Application Laid-Open No. 55-108279, etc.). Sterilization is performed while discharging from the through hole, and then the through hole is sealed under aseptic conditions.

(Problems to be solved by the invention) However, even with the conventional method of providing a through hole,
When performing steam sterilization using a steamer, etc., residual air in the container prevents the heated steam from being sent into the container, and the heated steam does not come into contact with the food smoothly. Cannot be performed satisfactorily.

Further, the sealing of the through holes is performed in a sterile room, but it is difficult to expect complete sterility in the food manufacturing process. When the inside of the container is cooled (by cooling), there is a problem that cold air outside the container is drawn in and the sterilized food may be contaminated.

An object of the present invention is to provide a sterilization method capable of reliably and efficiently performing heated gas sterilization with a basic object of solving the above problems.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the method for sterilizing packaged food of the present invention is provided with an inlet and an outlet in a packaging container in which food is stored. And the container is sealed except for the outlet, forcibly feeding the heated gas from the inlet, discharging the gas in the container from the outlet,
The feeding port and the discharging port are closed in a state where the inside of the container is filled with the heated gas.

The food is not particularly limited as long as it is subjected to heat gas sterilization, and is suitable for raw or boiled udon, spaghetti, cooked rice and the like.

Examples of the packaging container for storing the food include synthetic resin bags and tray containers, but are not limited thereto. However, because it comes into contact with heated gas,
Those having excellent heat resistance are desirable.

As the heating gas, heating air can be used in addition to the heating steam, and humidified heating air adjusted by appropriately adding moisture to the air can also be used.

Next, the inlet and outlet provided in the container can be constituted by small holes (gap) formed separately, or can be constituted by one small hole. In the case of using one small hole, the small hole may be partially assigned to the inlet and the outlet by means of a forced supply of heated gas to be described later. Further, the inlet and the outlet can be formed in a tubular shape. This pipe is prepared for each of the inlet and the outlet, and it is also possible to use one pipe double.

Next, as a means for forcedly feeding the heated gas, a method in which a heated gas ejection nozzle or the like faces the inlet or is directly inserted and the heated gas is sent from the ejected nozzle can be adopted. In the case where the inlet itself is formed in a tubular shape, it is conceivable that a heated gas is sent by connecting an ejection nozzle to the tube. In addition, the discharge of the gas in the air can be performed by natural exhaustion accompanying the supply of the heated gas, but it is also possible to discharge the gas by sucking the air gas from the discharge port.

The inside of the container is filled with the heated gas by the forced supply of the heated gas, and after the supply for a predetermined time, the inlet and the outlet in the post-process are closed in the filled state. It is desirable that the closing be performed while feeding the heated gas. However, since it is only necessary that the filled state of the container is maintained, the closing operation can be performed even after the supply of the heated gas.

Further, both the inlet and the outlet can be closed at the same time, but each can be closed sequentially. However, it is desirable to close the discharge port first in order to ensure the filled state of the heated gas in the container.

The above-mentioned inlet and outlet are closed by heat welding or the like.

For example, when a heating gas is fed by feeding a nozzle to the inlet, the nozzle is removed and then closed. In addition, when the nozzle faces the inlet, the blockage can be performed while injecting the heated gas, or the blockage can be performed after the injection is stopped.

Further, when the inlet and the outlet are formed in a tubular shape, the inlet and the outlet can be closed while the heated gas is being fed in, and then the excess pipe can be cut and removed. Alternatively, the pipe section may be cut and removed first, and then the inlet and outlet may be closed.

(Operation) That is, according to the present invention, the heated gas is reliably introduced into the container by forcibly feeding the heated gas from the inlet provided in the container. On the other hand, the air in the container is discharged to the outside of the container through the outlet, and the introduction of the heated gas into the container is smoothly performed. Therefore, the heated gas efficiently contacts the stored food, and the heat sterilization is performed efficiently.

Next, since the inlet and the outlet are closed in a state where the heating gas is filled in the container, cool air outside the container does not flow into the container, recontamination is prevented, and a reliable sterilization state is obtained. .

Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

Boiled spaghetti 2 which has been acid-adjusted to suppress heat-resistant bacteria is stored in a tray-shaped packaging container 1.
Is covered with a plastic film 3 and is heat-welded except for a small gap 4 which is partially unwelded.

The packaging containers 1 are sequentially transferred via a carry-in path 7 onto an annular and rotatable rotating table 6 and are arranged at a constant interval from each other. An annular heating steam supply pipe 8 that rotates in synchronization with the turntable 6 is disposed at a concentric position on an inner peripheral portion of the turntable 6. A steam generator is connected. Further, nozzles 9... 9 are protrudingly provided on the outer periphery of the heating steam supply pipe 8, and each nozzle 9 is positioned at the same angular interval as the packaging container 1 arranged on the turntable 6. An unloading path 10 is connected to the turntable 6, and a heat welding device 11 is disposed at an entrance of the unloading path 10.

Note that the turntable 6 and the heating steam supply pipe 8 are covered with a cylindrical cover 12, thereby preventing leakage of the heating steam from affecting the surrounding environment.

 Next, a method of an embodiment using a steam device will be described.

Packaging container 1 with small gap 4 aligned on one side on carry-in path 7
Are arranged at predetermined intervals, and are transported toward the turntable 6. At the leading end of the carry-in path 7, the packaging container 1 is delivered to the turntable 6, and the nozzle 9 is inserted into the small gap 4 as the turntable 6 and the heated steam supply pipe 8 rotate.

Next, heating steam generated by heating steam generation means (not shown) is supplied from a heating steam supply pipe 8 to nozzles 9.
And the packaging container 1 into which the nozzles 9 are inserted.
It is sent to the inside of each. On the other hand, the air in the packaging container 1 is discharged to the outside of the container 1 through the discharge port 4a. Therefore, the inside of the container is quickly filled with the heating steam, and the heating sterilization is efficiently performed.

Thus, the heating steam sterilization is performed for a predetermined time while rotating the turntable 6 and the heating steam supply pipe 8. Turntable 6
The nozzle 9 is withdrawn from the packaging container 1 that moves with the delivery container 10 as soon as it is delivered to the carry-out path 10. Immediately thereafter, the small gap 4 is thermally welded by the thermal welding device 11 in a state where the inside of the container 1 is filled with the heating steam. Is done.

As the heat welding device 11, for example, one having a structure in which an object to be welded is sandwiched between heating rollers and heated and welded is used.

The packaging containers 1 sealed as described above are sequentially taken out to the carry-out path 10. This operation is performed continuously, and as the packaging container 1 is fed into the carry-in path 7, the heat-sterilized packaging container 1 is continuously delivered from the carry-out path 10.

In this embodiment, a small gap 4 is provided between the packaging container 1 and the plastic film 3, and an inlet and an outlet are allocated to the small gap. Can be assigned to the inlet and outlet.

Second Embodiment Next, a second embodiment will be described with reference to FIGS. 3 and 4. FIG.

Inside the tray-type packaging container 20, as in the previous embodiment,
Boiled spaghetti 21 is stored, and the container end is covered with a plastic film 22.

A wax-shaped tube 24 is inserted between the packaging container 20 and the plastic film 22, and the plastic film 22 and the upper end of the container 20 are heat-welded except for the tube 24.

The packaging containers 20 are sequentially transferred on the belt conveyor 25 at predetermined intervals.

On the other hand, on the side of the belt conveyor 25, heating steam supply devices 26 are arranged at predetermined intervals, and have a heating steam supply nozzle 27 directed to the belt conveyor 25.
The packaging container 20 on the belt conveyor 25 is
The nozzle 27 moves in the direction A in the drawing according to the movement of the nozzle.
Heated steam from 27 is sent into vessel 20. On the other hand, the air in the container is discharged to the outside through the peripheral portion in the pipe 24, and the heated steam is efficiently sent into the container 20. Packaging containers 20
Is further moved by the belt conveyor 25, and the heating steam is continuously sent into the container 20 by the next heating steam supply device 26.

The container 20 thus heat-sterilized for a predetermined period of time
Heat welds the unwelded portion so that the tube 24 is crushed by the welding device 28 at the front. Next, the remaining tube protruding outward from the container 20 is cut and removed by the cutting device 29 further forward.

The above-described device group is covered with a cover 30,
Prevents the diffusion of heated steam used for heat sterilization to the surroundings. By positively setting the inside of the cover 30 to the heated steam atmosphere, there is also an effect that the re-contamination in the container 20 before closing the unwelded portion can be more reliably prevented.

In the above embodiment, the heating steam is continuously ejected from the nozzle 27. However, the heating steam may be intermittently ejected according to the approach and separation of the container 20.

Further, the welding of the unwelded portion in the container 20 was performed in front of the final heating steam supply device 26, but it is also possible to perform welding while the final heating steam supply device 26 is feeding heating steam. .

(Embodiment 3) Next, FIG. 5 shows a case where a double tube 31 is provided in a packaging container 32 instead of the tube 24 of the above embodiment. For example, the inner tube 31a is used as an inlet and the outer tube 31b is drained. Exit. The feeding of the heating steam is performed by abutting the heating steam feeding nozzle 33 on the inner pipe 31a.
The inside of the container 32 is evacuated by the outer tube 31b while feeding the heated steam from the nozzle 33.

After that, the double pipe 31 is closed and cut in the same manner as in the above embodiment. Also in this case, the stop of the supply of the heating steam can be arbitrarily selected before and after the closing operation.

In this embodiment, the outer tube 31b is open.However, for example, the nozzle 33 is a double tube, and the heating steam is supplied only through the inner tube, and the outer tube and the outer tube 31b are connected. It is also possible to connect and exhaust.

(Effects of the Invention) As described above, according to the present invention, a packaging container containing food is provided with an inlet and an outlet, respectively, and the container is removed except for the inlet and the outlet. Sealing, forcibly feeding the heated gas from the inlet, discharging the gas in the container from the outlet, and then closing the inlet and the outlet in a state where the inside of the container is filled with the heated gas, so that the packaging container There is an effect that the heated gas is reliably and efficiently sent into the inside, and the heat sterilization is quickly performed. Further, since the inlet and the outlet are closed in a state in which the container is filled with the heated gas, there is an effect that the packaging container can be sealed without a risk of recontamination.

[Brief description of the drawings]

FIG. 1 is a perspective view of a packaging container used in the method of one embodiment of the present invention, FIG. 2 is a schematic plan view of the same sterilizing apparatus, and FIG. 3 is a partially enlarged packaging container used in the method of another embodiment. FIG. 4 is a schematic plan view of the sterilizing apparatus, and FIG. 5 is a partially enlarged sectional view of a packaging container used in still another embodiment. DESCRIPTION OF SYMBOLS 1 ... Packaging container 2 ... Boiled spaghetti 3 ... Plastic film 4 ... Small gap, 4a ... Discharge port 8 ... Heated steam supply pipe 9 ... Nozzle, 11 ... Heat welding device 20 ... Packaging container 21 Boiled spaghetti 22 Plastic film 24 Double tube 25 Belt conveyor 26 Heated steam supply device 27 Nozzle 28 Welding device 29 Cutting device 31 Heavy pipe 32 …… Packing container mouth

Claims (1)

(57) [Claims] A packaging container containing food is provided with an inlet and an outlet, and the container is sealed except for the inlet and the outlet, and the heated gas is forced from the inlet. A method of disinfecting packaged food, wherein the gas is discharged from the container through the inlet, and then the inlet and the outlet are closed while the inside of the container is filled with the heated gas.