JPH0257563A - Denaturation preventive sealed bag - Google Patents

Abstract

PURPOSE:To prevent unwanted bacteria from intruding except fresh air and to exhaust harmful gases out of all around a bag material, by providing an opening somewhere and covering said opening with a filter having specified fine holes. CONSTITUTION:This bag is closely sealed bag heat-sealed on the peripheries of a film compounded with harmful gas absorber particles into a thermoplastic resin and it has an opening which is covered by a filter preventing fine particles with 0.01mu or more size from passing through it. The size of the opening depends on kinds of the contents and the size of the bag. The hole is air-tightly closed at the peripheries thereof by use of the finely porous filter to completely cover the opening. Gasses like oxygen, carbon mono oxide, etc. can pass through freely the porous filter. It shall be larger than 0.01mu or preferably larger than 0.02mu or more preferably larger than 0.05mu for the porosity of the filter not to let such microbes pass as mold, virus, bacteria, spores, etc.

Description

[Detailed description of the invention] [Industrial application field] The present invention is applicable to mushrooms, high-grade vegetables, meat, grains, processed foods,
This product relates to denaturation-preventing sealed bags that maintain freshness and prevent quality deterioration during the distribution and storage of agricultural seeds.

[Conventional technology]

Traditionally, when preserving foods such as mushrooms, high-grade vegetables, meat, grains, processed foods, agricultural seeds, and bulbs, sealing was used to prevent the intrusion of microorganisms and pest eggs. However, this method cannot eliminate harmful gases generated from inside. The contents may breathe, and some may emit ethylene gas, carbon dioxide gas, ammonia gas, and other odor components during the deterioration process. Even in trace amounts, such components have the effect of further accelerating the deterioration of the contents, so in some cases it is better to open the container and store it in order to allow the generated gas to dissipate. However, it is true that the packaging method that leaves gaps for air circulation inevitably leads to the contamination of various germs and accelerates contamination and deterioration due to microorganisms.

Furthermore, in order to absorb these gases and prevent the acceleration of deterioration, various gas absorbents were sometimes sealed inside. This method of sealing together with a harmful gas absorbent requires complicated work, and when the temperature rises, the generated gas cannot be absorbed completely and the freshness rapidly decreases.

Japanese Patent Application Laid-open No. 58-20671 discloses a method for packaging fresh plants in a bag made of a film with perforations on which a file-like rough surface has been transferred.
A method for preserving freshness is disclosed.

[Technical problem to be solved by the invention]

However, although the method disclosed in JP-A-58-20671 is somewhat effective, the holes obtained by transferring the file-like rough surface are large and difficult to distinguish with the naked eye, but are obvious when viewed with a magnifying glass. With such large perforations, air and bacteria can freely pass through.

Alternatively, the method of enclosing and sealing oxygen absorbers, ethylene absorbers, odor component absorbers, etc. requires that these agents be completely separated from the contents before being sealed, which is a complicated process. However, it was not possible to widely disperse the contents within the bag, and the effect was localized in the case of a large amount of contents. In addition, this method had a tendency to cause the contents to swell due to insufficient air circulation, thus accelerating denaturation.

Therefore, various foods and seeds that allow oxygen and carbon dioxide gas to pass through freely, do not allow microorganisms to pass through, and have the same effect as if they were encapsulated without specifically encapsulating a malignant gas absorbent. There was a need for sealed bags for animal and plant tissue.

[Means of problem solving]

The present invention aims to solve the above problems, and consists of a sealed bag made by fusing the periphery of a film manufactured by blending fine powder of a harmful gas absorbent into a thermoplastic plastic. An opening is provided in the section, and the opening is opened at 0.
It is characterized by being coated with a filter having micropores that do not allow fine particles having a diameter of 0.01 μm or more to pass through.

The bag material used in the present invention is preferably a film such as polyethylene or polypropylene that can seal the contents and can be heat-sealed. In the present invention, such film materials mixed with various gas-absorbing agents are used. As these harmful gas absorbents, finely crushed Cristobal stone such as Oya stone, 5iCh, TiO2, F
It is preferable to add a metal oxide such as e2O3 or NazO, sinter it, and further perform special oxygen treatment. Alternatively, porous adsorbents such as activated carbon and diatomaceous earth may also be used, but transparent porous materials are preferred. Plastic kneaded with these ingredients contains ethylene generated from the contents. It has the effect of absorbing ammonia and other harmful gases and preventing denaturation of the contents.

Such harmful gas absorbents are 0.0% compared to plastics.
It is blended in an amount of 5 to 20% by weight, preferably 1 to 10% by weight.

If it is less than 0.5% by weight, the harmful gas absorption effect will not be sufficient;
If the amount exceeds 20% by weight, the film forming properties, heat fusion properties and other properties of the plastic will be lost.

An opening is made in the sealed bag. The opening may be square or round, and its size varies depending on the type of contents and the size of the bag. A filter having fine pores large enough to completely cover the opening is used to seal the periphery of the pore by welding, gluing, or other methods to block air permeability. Gases such as oxygen and carbon dioxide can flow into the bag through the micropores of the filter. The opening is not limited to a thank-you note; it can also be provided in the form of a long strip.In this case, the filter can be placed across the opening,
All you have to do is place the filter in close contact with both edges of the opening. Also,
Two or more openings may be provided.

A filter with micropores does not allow microorganisms such as mold, viruses, bacteria, and spores to pass through, that is, 0.
Any filter may be used as long as it has fine gaps that do not allow fine particles of 0.01μ or more, preferably 0.02μ or more, more preferably 0.05μ or more to pass through. However, in order to ensure smooth air circulation, it is desirable that the resistance to gas passage be low, and a single-layer filter with continuous uniform pores of controlled size is preferred. For example, DuraGuard (trade name) manufactured by Celanese, USA is a porous film made of polypropylene, with a 0.02 to 0.04
It is a filter with a single layer of through-holes of about μ x 0.2 to 0.4 μ, and if a hydrophobic material is used, microorganisms have a high affinity with water, so it is difficult for microorganisms to pass through, and the pore size is the same. Even so, the effect of blocking germs is further enhanced.

[Effect]

The present invention does not simply hermetically enclose the contents;
It is sealed in a sealed bag equipped with a filter that has minute perforations that do not allow microorganisms to pass through and allow harmful gases to pass through, while allowing oxygen and carbon dioxide to freely pass through so that cells can breathe, and the bag material itself does not contain harmful gases. By providing an absorbent function, the entire bag material has the effect of an absorbent even without encapsulating a gas absorbent inside. Therefore, it is possible to effectively prevent the contents from deteriorating due to the synergistic effect of the sterilization and free air circulation and the ability to absorb harmful gases throughout the bag material. In addition, by using cold storage, even contents that are prone to spoilage can be kept fresh for a longer period of time.

〔Example〕

5iOz87%, Al2O, 5%, Fezo, 11.5
%, 1% or less of CaO, Na, 0, Tie,, Mg0S
Crushed natural Cristobal stone containing K and O, and a small amount of Tie and Fe2O! Approximately 4% of the harmful gas absorbent, which was made by adding and sintering fine powder and absorbing oxygen, was kneaded into raw polypropylene and extruded to obtain a transparent film with a thickness of 40 μm.

Using this film, circumference 50cn+, depth 50c1
Eleven bags were manufactured, and a circular opening with a diameter of 2 cm was punched at a position of about 1/3 from the bottom of each bag. In this opening, a nearly square hydrophobic Duragard with a side length of 40II+ (
A polypropylene single-layer microporous film (trade name, manufactured by Celanese, Inc.) was fused to form a harmful gas-absorbing sealed bag. Therefore, the opening of this bag was completely covered by DuraGuard.

Shiitake mushrooms cultivated throughout the year were stored in the above-mentioned sealed bag, and the bag opening was fused. These sealed shiitake mushrooms maintained satisfactory freshness for two weeks even when stored at 20°C, and did not lose their aroma.

Separately, when the same amount of shiitake mushrooms collected at the same time were sealed in polyvinylidene chloride bags of the same size and shape and without micropores, the back side of the caps turned brown after two days. Furthermore, when the bag was sealed in a regular polypropylene bag with micropores of the same size and shape, the back side of the bag turned brown after 10 days.

〔effect〕

According to the present invention, it is possible to provide a sealed bag that can exclude bacteria from entering while supplying air and eliminate harmful gases from the entire bag material, and can safely store contents that are difficult to maintain freshness for a long time. can.

Claims (1)

[Claims] It is a sealed bag made by fusing the periphery of a film made by blending fine powder of harmful gas absorbent with thermoplastic plastic, and has an opening in a part of the bag.
A denaturation-preventing sealed bag characterized by being coated with a filter having micropores that do not allow fine particles having a diameter of μ or more to pass through.