JPH04252160A - Apparatus for storing food or such - Google Patents

Abstract

PURPOSE:To provide a preservation apparatus for food, etc., effective for lowering the humidity and eliminating ethylene in a vessel and exhibiting excellent preservation performance. CONSTITUTION:A vessel 1 for the preservation of food, etc., is provided with a vacuum pump 2 for sucking and discharging the air in the vessel and a connection port 4 on the vessel wall to introduce outer air into the vessel 1. A gas- permeation membrane 5 is attached to the connection port 4. The gas permeation membrane 5 is produced by covering a polypropylene fiber non-woven fabric with a polymeric material composed mainly of a polydimethylsiloxane and has a steam permeability 120 times as large as a nitrogen permeability. Gases (e.g. ethylene gas) exerting adverse effects on the preservation of food are removed from the vessel by driving the vacuum pump 2. Steam is selectively introduced from the outer air through the gas-permeable membrane 5 by the pressure-difference between both faces of the membrane 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for storing foods, etc., which maintains humidity inside a container using a gas permeable membrane.

0002

BACKGROUND OF THE INVENTION In recent years, there has been a strong preference for high-end eating habits, and as demands for freshness of food have increased, strong interest has been focused on preservation methods.

Conventionally, it has been widely known that it is effective to control temperature and humidity as well as to adjust the atmosphere in which the food is stored to have an appropriate gas composition when it comes to preserving foods and the like.

[0004] In addition, attempts have been made to maintain the atmosphere inside the container in an appropriate state in food storage devices, and as a method of creating a preservation environment, there are methods that overcome the drawbacks of hypobaric storage, which stores foods at low temperatures and low pressures. An improved version is proposed in Japanese Patent Publication No. 53-24347.

[0005] An experimental example of the configuration is added below, as shown in Fig. 5.
This will be explained with reference to FIG. As shown in the figure, it consists of an airtight container 1 for storing food, etc., a vacuum pump 2 that suctions and exhausts the air inside the container 1, a leak adjustment device 3 that adjusts the pressure inside the container 1, etc. has been done.

To explain the operation of the storage device constructed as above, first, the vacuum pump 2 is operated to lower the pressure to a preset pressure P1 (660 mmHg), and then the operation of the vacuum pump 2 is stopped. At this time, the container 1 is maintained at a temperature suitable for the stored items, and the leak adjustment device 3 of the container 1 is adjusted so that the pressure becomes P2 (740 mmHg) during a preset time T2 (60 minutes). Keep it. When the pressure reaches P2 again, the vacuum pump 2 is activated, and after the pressure drops to P1, the operation of the vacuum pump 2 is stopped.
By repeating this operation, the stored material is stored. As an experimental example, if the stored food is vegetables, the appropriate temperature 6
The optimal temperature is around 0°C, and if the storage device is installed and used in a room with that atmosphere, the initial water vapor pressure outside the container 1 will be 4.
．． When the water vapor pressure is 2 mmHg, the water vapor pressure inside the container 1 becomes higher than that outside the container 1 due to the evaporation of vegetables, so the pressure becomes 7 mmHg. As a result, by repeating the operation of the vacuum pump 2 described above, the water vapor pressure within the container 1 gradually decreases as shown in FIG.

[0007]

However, in the conventional configuration described above, the water vapor pressure outside the container 1 is lower than the water vapor pressure inside the container 1, and even if air is sucked in from the leak adjustment device 3, the humidity inside the container 1 cannot be reduced. There was a drawback that it was not possible to raise the level and maintain it at a certain level.

The present invention solves the above-mentioned conventional problems, and aims to provide a storage device for foods, etc., which has a simple structure and can maintain the humidity inside the container at a constant level.

[0009]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an airtight container for storing food, etc., a depressurizing means for sucking and discharging the air inside the container, and an outer shell of the container. The container is equipped with a communication port for guiding the atmosphere, and a gas-permeable membrane attached to the communication port, and selectively introduces water vapor into the container via the gas-permeable membrane, and
An on-off valve is installed in the pipeline between the communication port and the gas permeable membrane,
The opening/closing valve is configured to close when the pressure is reduced.

0010

[Operation] With the above structure, the gas inside the container is discharged by the pressure reducing means, and the pressure difference created between the outside air and the inside of the container allows water vapor to selectively permeate from the atmosphere through the gas permeable membrane, creating air with saturated water vapor. The humidity inside the container can be maintained by supplying the air, and the pressure can be reduced quickly by closing the on-off valve when discharging the air inside the container using the pressure reducing means.

[0011]

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3.
This will be explained with reference to. In this embodiment, the same components as those shown in the above-mentioned conventional example are given the same reference numerals, and the explanation thereof will be omitted. The characteristic structure of this embodiment is that a communication port for introducing the atmosphere is provided in the outer shell of the container portion described in the conventional example, and a gas permeable membrane is attached to this communication port. That is, a communication port 4 for introducing the atmosphere is provided in the outer shell of the container 1, and a gas permeable membrane 5 is attached to the communication port 4. The gas permeable membrane 5 is made by coating a polypropylene fiber nonwoven fabric with a polymeric material mainly composed of polydimethylsiloxane, and has a characteristic that the permeation amount of water vapor is 120 times that of nitrogen.

To explain the operation of the above configuration, first, by driving the vacuum pump 2, gases that are harmful to preservation, such as ethylene gas, are removed from the container 1, and when a pressure difference is created in the gas permeable membrane 5, it is removed from the atmosphere. Water vapor is selectively introduced through the gas permeable membrane 5.

As an experimental example, the temperature inside the container 1 was initially 6° C. and the water vapor pressure was 7 mmHg, and the temperature outside the container 1 was 6° C. and the water vapor pressure was 4.2 mmHg. When a storage device for food, etc. is installed in a room with that atmosphere and operated, the pressure inside container 1 changes from 760 mmHg to P1 (660 mmHg), and then the vacuum pump 2 is stopped and the inside of container 1 is The pressure of P2 (74
After returning to 0 mmHg), repeat the same operation again. In addition, when vacuum pump 2 is stopped, vacuum pump 2
Air should not flow back into the container 1 through the tube. The results of investigating the pressure fluctuations and water vapor pressure changes inside container 1 at this time (when nothing is inside container 1) are shown in Figure 3. Even without returning the pressure to atmospheric pressure (760 mmHg), it returns to 7 mmHg, which is the saturated water vapor pressure at 6°C. Therefore, since the saturated water vapor pressure is 7 mmHg at 6°C, there is no condensation on the walls of the container 1 or the food, and the humidity inside the container 1 can be maintained at conditions suitable for storage, and the concentration of ethylene gas can be reduced. By doing so, it is possible to prevent vegetables etc. from rotting. In this example, the polymer material of the gas permeable membrane 5 was a polymer mainly composed of polydimethylsiloxane, but other materials may be used as long as they have good water vapor permeability. The following effects can be obtained. Further, the intermittent operation of the vacuum pump 2 can be easily achieved by using a relay (not shown), and its explanation will be omitted.

FIG. 4 shows another embodiment of the present invention, in which the same parts as in FIG. 1 are denoted by the same numbers. The difference from the previous embodiment is that the communication port 6
An on-off valve 8 is provided in the conduit 7 between the gas permeable membrane 5 and the gas permeable membrane 5,
When reducing the pressure inside the container 1 with the vacuum pump 2, the on-off valve 8
According to this structure, the time T required for the pressure to reach P2 when depressurizing is shortened.
This has the effect of shortening the driving time of the vacuum pump 2. Note that the opening/closing of the opening/closing valve 8 and the interlocking of the vacuum pump 2 and the like can be easily realized by using a relay (not shown), and a description thereof will be omitted.

[0015]

Effects of the Invention As is clear from the description of the embodiments above, the food storage device of the present invention comprises an airtight container for storing food and a decompression means for sucking and discharging the air inside the container. and a communication port provided on the outer shell of the container to introduce the atmosphere, and a gas permeable membrane attached to the communication port, and water vapor is selectively introduced into the container via the gas permeable membrane. With this configuration, it is possible to maintain the humidity inside the container at conditions suitable for storage with a simple structure, and by reducing the concentration of ethylene gas, it is possible to prevent spoilage of vegetables etc. can be stored for a long time.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional front view of a storage device for foods, etc. in an embodiment of the present invention.

[Figure 2] Pressure change diagram inside the container of the same storage device

[Figure 3] Chart of changes in water vapor pressure inside the container of the same storage device

FIG. 4 is a schematic cross-sectional front view of a storage device for foods, etc. according to another embodiment of the present invention.

[Fig. 5] Schematic cross-sectional front view of a conventional storage device

[Figure 6] Pressure change diagram inside the container of the same storage device

[Figure 7] Chart of changes in water vapor pressure inside the container of the same storage device

[Explanation of symbols]

1 Container 2 Vacuum pump (decompression means) 4 Communication port 5 Gas permeable membrane

Claims (2)

[Claims] Claim 1: An airtight container for storing food, etc., a depressurizing means for sucking and discharging the air in the container, a communication port provided on the outer shell of the container for introducing gas, and a communication port attached to the communication port. What is claimed is: 1. A storage device for food products, etc., comprising: a gas permeable membrane; 2. The storage device for foods and the like according to claim 1, wherein an on-off valve is provided in the conduit between the communication port and the gas permeable membrane, and the on-off valve is closed when the pressure is reduced.