JP2002037347A - Freshness keeping package for shimeji mushroom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a freshness keeping package for shimeji mushrooms which is excellent in appearance and freshness keeping effects. SOLUTION: The freshness keeping package of shimeji for hermetically packaging shimeji mushrooms comprises, a nylon single-layer film whose steam permeability is 30 to 180 g/m2.24 hr.atm (at 40 deg.C with relative humidity(RH) of 90%), or a multi-layer film of a nylon and a polyethylene, or a multi-layer film of a nylon and an ethylene-vinyl acetate copolymer, or a multi-layer film of a nylon and a resin comprising a mixture of a polyethylene and an ethylene- vinyl acetate copolymer, or a multi-layer film of a nylon and an ethylene vinyl alcohol copolymer. An oxygen concentration in the package is 0.05 to 1% due to breathing of the mushrooms themselves, and a reduction in weight of the whole package is less than 1% per day.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an object to maintain the freshness of a shimeji by suppressing the respiration of the shimeji even after packaging the shimeji, and by appropriately discharging the water evaporated from the shimeji from the bag. It relates to a package.

[0002]

2. Description of the Related Art In recent years, a freshness maintaining material for fruits and vegetables having an MA (Modified Atomospher) effect has been developed, and is mainly used for distribution. Fruits and vegetables continue to breathe after harvest,
It is known that when placed in an environment having a lower oxygen concentration than the atmosphere (about 21% of oxygen and about 0.04% of carbon dioxide) and a high carbon dioxide concentration, respiration is suppressed and freshness can be maintained. However, if the package is in an environment of excessively low oxygen and high carbon dioxide, the fruits and vegetables will cause respiratory disorders and accelerate deterioration, and conversely, the oxygen concentration will be too high,
If the carbon dioxide concentration is too low, a sufficient freshness retaining effect cannot be obtained. Also, if the humidity inside the package is too high, water droplets may form on the inside, making it difficult to see the inside, mold may develop, and fruits and vegetables may rot. Not preferred. That is, it is extremely important to control the inside of the package to an appropriate oxygen concentration, carbon dioxide concentration, and humidity. Here, since the respiration amount of fruits and vegetables is completely different depending on the type, temperature, cutting method, and the like, it is necessary to adjust the gas permeation amount and humidity of the packaging material according to the respiration amount. When fruits and vegetables are hermetically sealed using a polymer film such as drawn polypropylene or polyethylene which is often used for packaging of fruits and vegetables as it is, oxygen in the packaging is consumed by respiration and becomes low in oxygen, resulting in poor freshness. For this reason, M
A film has been developed in which micropores (pore diameter of several hundreds μm or less) or scratches are formed for the purpose of maintaining freshness by A, and processing such as increasing the amount of oxygen gas permeation depending on the number or size thereof is developed. In any of these methods, the amount of oxygen permeation, the amount of carbon dioxide permeation, and the moisture permeability are determined by the material, thickness, number of micropores and scratches, or the size of the film. That is, it means that it is impossible to freely set the oxygen permeation amount, the carbon dioxide permeation amount, and the moisture permeability independently. When using a low moisture permeable resin such as stretched polypropylene, and puncturing the shimeji with fine pores and a predetermined oxygen permeability, the moisture permeability is insufficient and water droplets are attached to the package,
Problems such as discoloration of mold and mold growth may occur. In addition, when shimeji is wrapped in polyvinyl chloride wrap on a polystyrene tray, environmental problems when treating the tray and PVC, and cases that consumers and retailers dislike as excessive packaging have come up. Furthermore, polyolefin wraps have also appeared as an alternative to polyvinyl chloride, but they have not been able to function satisfactorily because there are many complaints about poor adhesion and insufficient anti-fogging properties to cause condensation during distribution. Japanese Patent Application Laid-Open No. 4-57763 discloses a method for packaging mushrooms, Japanese Patent Application Laid-Open No. 8-119358 discloses a fresh shiitake mushroom package, and Japanese Patent Application Laid-Open No. 10-117677. The official gazette discloses a film for packaging fruits and vegetables. These use a single-layer film of polystyrene or the like or a polystyrene-based film of a multilayer film of an ethylene-vinyl acetate copolymer, but these films have no rigidity, have fine wrinkles in the appearance after packaging, and feel freshness. However, there are drawbacks such as that they cannot be used and are difficult to use in automatic packaging machines because they are easily torn.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a shimeji freshness preserving package which has not been obtained conventionally and has good shimeji preservability and beautiful appearance.

[0004]

The present invention provides: (1) a water vapor permeability of 30 to 180 g / m ² · 24 hr · atm;
(At 40 ° C./90% RH) nylon monolayer film, nylon and polyethylene multilayer film, nylon and ethylene-vinyl acetate copolymer multilayer film, or nylon, polyethylene and ethylene-vinyl acetate copolymer In a package that seals and seals a shimeji with a multi-layer film of a resin mixed with or a multi-layer film of nylon and an ethylene vinyl alcohol copolymer, the oxygen concentration in the package becomes 0.05 to 1% due to the respiration of the shimeji itself. And a shimeji freshness preserving package wherein the weight loss of the entire package is less than 1% per day. (2) A material obtained by laminating polyethylene on paper or a material obtained by laminating ethylene-vinyl acetate copolymer on paper or a resin obtained by mixing polyethylene and ethylene-vinyl acetate copolymer on paper on one side or a part of the package. The shimeji freshness retaining package according to (1), wherein at least one of the laminated materials is used in combination. (3) The shimeji freshness retaining package according to the above (1) or (2), wherein the shimeji is a shimeji having a shape or a shimeji cut into pieces. (4) The single-layer film or the multilayer film has one or more micropores or scratches per bag in which the opening area of one opening is 0.05 mm ² or less per bag (1) to (1). 3)
Item 7. The package for maintaining freshness of shimeji according to the above item. (5) The oxygen permeation amount of the single-layer film or the multilayer film is 1
The shimeji freshness preserving package according to any one of (1) to (4), which has a 000 to 20,000 cc / m ² · 24 hr · atm. (6) The freshness retaining package according to any one of (1) to (5), wherein a surfactant is applied to the single-layer film or the multilayer film to perform an anti-fog treatment. (7) The freshness retaining package according to any one of (1) to (6), wherein the package is provided with a zipper-type opening / closing part and sealed with a zipper. Is provided.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The film used in the present invention has a water vapor transmission rate of 30 to 180 g / m ² · 24 hr · atm (at 40 ° C. · 9
0% RH). 30g / m ² · 24hr
If the temperature is lower than atm (at 40 ° C./90% RH), dew condensation occurs in the package, and a problem of accumulation of water occurs. this is,
The accumulated water causes discoloration of the shimeji mushrooms, as well as a bad appearance. 180g of water vapor transmission rate
/ M ² · 24hr · atm, weight loss is 1w per day
Exceeding t%, loss is increased. Specifically, a nylon single-layer film, or a multilayer film of nylon and polyethylene, or a multilayer film of nylon and ethylene-vinyl acetate copolymer, or nylon, and a resin obtained by mixing polyethylene and ethylene-vinyl acetate copolymer Or a multilayer film of nylon and an ethylene vinyl alcohol copolymer. A resin in which paper and at least one of polyethylene, polypropylene, and ethylene-vinyl acetate copolymer are laminated on one side or a part of the package may be used. The thickness of the film used in the present invention is 1
0 to 90 μm is preferred. When the thickness exceeds 90 μm, the oxygen permeability, the carbon dioxide permeability, and the water vapor permeability are reduced, so that there is no practicality. On the other hand, if the thickness is less than 10 μm, the strength is weak and the product cannot be used as a packaging material. These films may be subjected to a stretching treatment, or may be laminated after being subjected to a stretching treatment. By performing the stretching treatment, the stiffness is strengthened, and fine wrinkles are less likely to be formed in the form after packaging. The oxygen permeability of the film used in the present invention is 1000
It is preferably from 20,000 cc / m ² · 24 hr · atm to maintain freshness of shimeji. 1 in the state of one shimeji strain
It is preferably from 000 to 5000 cc / m ² · 24 hr · atm. 1
If it is less than 000, it becomes oxygen deficient, that is, 0%, and alcoholic odor is generated by anaerobic respiration, and its commerciality is reduced. If it exceeds 5,000, the oxygen concentration exceeds 1%, and aerial hyphae are generated in the umbrella, The merchantability decreases. In the case of a shimeji which has been cut one stem at a time, it is preferably 6000 to 20000 cc / m ² · 24 hr · atm. If it is less than 6000, it becomes oxygen deficient, that is, 0%, and alcoholic odor is generated by anaerobic breathing, and the commercial value is reduced.
If it exceeds 000, the oxygen concentration exceeds 1%, and aerial hyphae are generated on the umbrella, and the commerciality is reduced. In order to adjust the oxygen transmission rate, the carbon dioxide transmission rate, and the moisture permeability of the film used in the present invention, conventional processing such as forming fine holes (pore diameter of several hundred μm or less) or scratches may be performed. This processing may be performed before the lamination or after the lamination. In order to properly control the oxygen concentration in the package, the opening area of at least one opening is 0.0
It is preferably 5 mm ² or less. If it is larger than this, the amount of transmission per opening becomes too large, and it becomes difficult to control the atmosphere in the package.

[0006] The film used in the present invention is preferably subjected to anti-fogging treatment. As a method of the anti-fogging treatment, the anti-fogging agent may be kneaded into the film in advance, or may be applied to the surface of the film. The former is excellent in maintaining the anti-fogging property, while the latter is capable of obtaining excellent anti-fogging property immediately after packaging. The performance of the antifogging agent used is often stored at 30 ° C. or lower from the viewpoint of maintaining the freshness of the shimeji, and those having good antifogging properties at low temperatures are preferable. Specifically, it is preferable that the fatty acid contains an ester surfactant of a fatty acid that is a saturated fatty acid having 8 to 12 carbon atoms or an unsaturated fatty acid having 16 to 20 carbon atoms and a polyhydric alcohol. For example, sorbitan monolaurate, diglycerin oleate and the like can be mentioned. When the antifogging agent is kneaded, the surface of the film may be corona-treated to immediately give an antifogging effect, or when the antifogging agent is applied, the film will be blocked, and a sliding powder may be applied to the surface.

[0007] The shape of the shimeji used in the present invention is not particularly limited, and examples thereof include stocks and cut ones. In the case of the cut state, the respiratory volume increases, so it is necessary to increase the oxygen permeation amount. Evaluation of the storage stability of Shimeji is that it has good firmness and odor and does not generate aerial hyphae. In order to obtain a freshness maintaining effect, the oxygen concentration in the package must be 0.05 to 1%, and the weight loss must be less than 1% per day. If the oxygen concentration is less than 0.05%, an ethanol odor or putrefaction odor may be generated. When the oxygen concentration exceeds 1%, aerial hyphae may be generated. If the water vapor transmission rate is selected in accordance with the present invention, discoloration of the shimeji can be prevented, but if the weight loss exceeds 1% per day, not only will the consumer be reduced, but also the shimeji will be softened or wilted.

When the package of the present invention is processed into a bag or when the contents are filled and sealed, any means such as heat seal, high frequency seal, ultrasonic seal, and openable zipper may be used. The seal may be partially processed to be easily opened. Especially because the openable zipper does not use a machine called a sealer,
This is preferable because there are merits that the installation cost, maintenance cost, and installation space of the machine are unnecessary. The important thing is that the amount of oxygen permeated from the seal is sufficiently smaller than the amount of oxygen permeated from the film and can be neglected in practical use.Bundling holes, rubber bands, adhesive tape, wire-like objects, plastic fasteners The method of sealing with etc. is also included in this.

[0009]

[Example 1] [Example 1] Unitica Co., Ltd., thickness 25μ
m biaxially stretched nylon film (trade name: emblem, water vapor transmission rate: 160 g / m ² · 24 hr (at 40 ° C.
90% RH) on the sealing surface side, a hole was formed in a product coated with sorbitan monolaurate (trade name: LEODOL SUPER SP-L10 (F)) manufactured by Kao Corporation to a thickness of 0.1 μm. 30 micropores with an area of 0.003 mm ²
Pieces / m ² (oxygen permeation amount: 3300
cc / m ² · 24 hr · atm). A bag having an inner size of 200 mm × 200 mm was prepared from the film, filled with 100 g of shimeji stock, sealed with heat seal, and stored at 15 ° C. << Example 2 >> A multilayer film in which a 20 μm ethylene-vinyl acetate copolymer was laminated on a 15 μm thick biaxially stretched nylon film (water vapor transmission rate: 110 g / m ^2.
24hr provided (at40 ℃ · 90% RH) ) open area ratio 0.004 mm ² of micropores sealing surface antifogging agent of Example 1 to those 0.1μm coated in a 39 / m ² uniformly and (oxygen permeability: 4700cc / m ² · 24h
r · atm). From this film, inner size 200mm × 20
A 0 mm bag was prepared, filled with 100 g of shimeji mushrooms, sealed with a heat seal, and stored at 15 ° C. << Example 3 >> A film obtained by applying the antifogging agent of Example 1 to the sealing surface of the multilayer film of Example 2 had an open area of 0.002.
Micropores of mm ² were uniformly provided at 200 holes / m ² (oxygen permeation amount: 14000 cc / m ² · 24 hr · atm). on the other hand,
A multilayer film (50 g of water vapor transmission rate) obtained by laminating a mixture of paper (30 g / m ² ), 35 μm of polyethylene and ethylene-vinyl acetate copolymer at a weight ratio of 1: 1.
/ M ² · 24 hr (at 40 ° C. · 90% RH), oxygen permeation amount 6000 cc / m ² · 24 hr · atm), cut both films into 220 mm × 220 mm, and 10 mm so that the sealing surfaces meet. A bag having a seal inner size of 200 mm × 200 mm was prepared, and 150 g of shimeji, each of which was cut into stems, was sealed and packaged by heat sealing and stored at 15 ° C.

Comparative Example 1 Biaxially stretched anti-fogging OPP having a thickness of 25 μm (water vapor transmission rate 6 g / m ² · 24 hr (at 40
(90 ° C./90° C.) and 25 / m ² micropores having an opening area of 0.003 mm ² were uniformly provided (oxygen permeation amount: 3300).
cc / m ² · 24 hr · atm). A bag with an inner size of 200 × 200 mm was prepared from this film,
0 g was sealed and packaged by heat sealing and stored at 15 ° C. << Comparative Example 2 >> Low-density polyethylene having a thickness of 30 μm (water vapor transmission rate: 20 g / m ² · 24 hr · at 40 ° C. · 90%
RH, oxygen permeation amount: 6000 cc / m ² · 24 hr · a
tm) to make a bag with an inner size of 200 mm x 200 mm,
100 g of shimeji shimeji is hermetically sealed and packed by heat sealing.
Stored at 5 ° C. << Comparative Example 3 >> Example 1 was applied to the sealing surface of the film of Example 1.
Coated with anti-fog agent (oxygen permeation amount: 25 cc /
m ² · 24hr · atm) and the secondary to the biaxially stretched polypropylene open area 0.004 mm ² micropores provided in 1 m ² per 128 uniformly (oxygen permeability: 22300cc / m ² · ²
4 hr.atm) film was prepared. Using each film on one side, a bag having an inner size of 200 mm × 200 mm was prepared, 100 g of a shimeji shimeji was hermetically sealed by heat sealing and stored at 15 ° C. << Comparative Example 4 >> A film obtained by applying the anti-fog agent of Example 1 to the film of Example 1 (oxygen permeation amount: 25 cc / m ² · 24)
hr · atm). 200mm × 200 from this film
mm bags were prepared, 100 g of shimeji mushrooms were hermetically sealed by heat sealing, and stored at 15 ° C. << Comparative Example 5 >> A biaxially stretched nylon film having a thickness of 15 µm (trade name: Santo Neil, water vapor transmission rate: 250 g / m)
² · 24hr · ^at40 the ℃ · 90% RH) to a first embodiment of the anti-fogging agent applied and open area ratio 0.07 mm ² of the micropores provided in 1 m ² per 28 uniformly (oxygen excess: 70000
cc / m ² · 24 hr · atm). 2 from this film
A bag of 00 mm x 200 mm was made, and a shimeji
0 g was sealed and packaged by heat sealing and stored at 15 ° C. << Comparative Example 6 >> The anti-fog agent of Example 1 was applied to the same film as Comparative Example 5, and 121 fine holes having an opening area ratio of 0.003 mm ² were uniformly provided per 1 m ² (oxygen permeation amount: 240).
00 cc / m ² · 24 hr · atm). A 200 mm × 200 mm bag was prepared from this film, and 100 g of a shimeji stock was hermetically sealed by heat sealing and stored at 15 ° C. << Comparative Example 7 >> A bag of 200 mm x 200 mm was prepared from the film treated in the same manner as in Example 1, and 150 g of shimeji cut into individual stems was hermetically sealed and packaged by heat sealing.
Stored at 15 ° C.

Table 1 shows the evaluation results of Examples and Comparative Examples. The symbols in the table are as follows. Freshness (condensation, discoloration, loss of sight, odor) ○: good, △: beyond product limit, ×: remarkable deterioration Hyphae: generation of aerial hyphae, ○: none, △, ×: remarkable generation

[0012]

[Table 1]

[0013]

According to the package of the present invention, it is possible to supply a shimeji which is excellent in the appearance of a film, has good freshness, and has little loss.

Claims (7)

[Claims] 1. A water vapor transmission rate of 30 to 180 g / m ² · 24
hr.atm (at40 ° C. 90% RH) nylon single layer film, nylon and polyethylene multilayer film, nylon and ethylene-vinyl acetate copolymer multilayer film, or nylon, polyethylene and ethylene-vinyl acetate In a package in which a shimeji is hermetically sealed with a multilayer film of a resin mixed with a copolymer or a multilayer film of nylon and an ethylene vinyl alcohol copolymer, the oxygen concentration in the package is 0.05 to 1 due to the respiration of the shimeji itself.
%, And the weight loss of the whole package is less than 1% per day. 2. A material obtained by laminating polyethylene on paper or a material obtained by laminating ethylene-vinyl acetate copolymer on paper, or a paper or a mixture of polyethylene and ethylene-vinyl acetate copolymer on one side or a part of a package. 2. The freshness retaining package according to claim 1, wherein a combination of at least one of resin-laminated materials is used. 3. The package according to claim 1, wherein the shape of the shimeji is a shimeji or a shimeji which is cut into pieces. 4. The package according to claim 1, wherein the single-layer film or the multi-layer film has one or more micropores or scratches per bag in which one opening has an opening area of 0.05 mm ² or less.
4. The shimeji freshness holding package according to any one of items 3 to 3. 5. The package according to claim 1, wherein the single-layer film or the multilayer film has an oxygen permeability of 1,000 to 20,000 cc / m ² · 24 hr · atm. 6. The package according to claim 1, wherein a surfactant is applied to the single-layer film or the multilayer film to perform an anti-fog treatment. 7. The freshness retaining package according to claim 1, wherein a zipper-type opening / closing part is provided to the package and sealed with a zipper.