JP3358268B2 - Freshness preserving packaging material for mushrooms and method of preserving freshness - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging material capable of maintaining the freshness of mushrooms for a long period of time, and more particularly to adjusting the gas concentration in the packaging by adjusting the gas permeability of the packaging material. The present invention relates to a freshness-retaining packaging material for mushrooms for maintaining freshness of fruits and vegetables, and a freshness-retaining method using the packaging material.

[0002]

2. Description of the Related Art At present, packaging forms of mushrooms include single-layer or co-extruded film bags of polypropylene or polyethylene, tray packaging of foamed polystyrene, and net packaging. However, these packaging methods have various problems because the packaging material to be used is determined without considering the physiological characteristics of mushrooms. For example, in bag packaging of enoki and the like, mushrooms cause anaerobic respiration due to a decrease in the oxygen concentration in the bag and generate an odor such as alcohol odor. If the oxygen concentration does not decrease due to poor sealing or the like, the enoki grows and deforms. In Shimeji tray packaging,
Due to incomplete sealing, the oxygen concentration in the container increases,
A mold-like aerial mycelium is generated, reducing the commercial value. Further, in net packaging such as shiitake mushrooms, discoloration such as browning or opening of bulk or drying due to evaporation of water proceeds.

[0003] These problems, except for the evaporation of water, occur because the oxygen concentration in the packaging is not optimal for the mushroom. In the case of fruits and vegetables, there is a method of maintaining the freshness of fruits and vegetables by adjusting the gas composition in the package to a state that is optimal for the fruits and vegetables as a package for maintaining freshness. In this method, the fruits and vegetables are packaged in a packaging material having an oxygen permeability selected according to the respiratory volume of the fruits and vegetables, whereby the gas composition in the packaging is adjusted to maintain the freshness of the fruits and vegetables. The oxygen permeability at that time varies depending on the type of fruits and vegetables, but it is generally said that an oxygen permeability of several thousands to tens of thousands of cm ³ / m ² · 24 hr · atm is required. However, at present, such freshness preserving packaging is not performed for mushrooms.

[0004] In addition, all of the above-mentioned packaging forms of the fruits and vegetables freshness preserving packaging material are bags at present. Even if this packaging material and packaging form are applied to mushrooms, mushrooms are very fragile products. Has the disadvantage of being damaged by weight. On the other hand, tray packaging solves the problem of damage due to such loads, but mushrooms can easily move in the container, causing damage, and when disposing of the container at the consumer stage, It is bulky and has contributed to the recent waste problem.

[0005]

According to the present invention, in order to solve the above-mentioned problems, it is possible to maintain the freshness of the mushroom in a packaging form which protects the contents so that the mushroom is not damaged during transportation and sale. That is, generation of off-flavor, generation of aerial hyphae,
The present invention provides a freshness-retaining packaging material for mushrooms comprising a plastic container having an oxygen permeability capable of obtaining a gas composition that does not cause discoloration, elongation, etc., and which is easy to dispose of, and a method for maintaining freshness using the same. The purpose is to provide.

[0006]

In order to solve the above-mentioned problems, a freshness retaining packaging material for mushrooms according to the present invention comprises a deep drawing container and a plastic film lid material which is heat-sealed at a flange portion of the container. A plastic film serving as a lid material having a mushroom storage temperature of 20,0.
00-100,000cm ³ / m ²・ 24hr ・ atm
It is preferable that the deep drawn container has substantially the same shape as that of the mushroom.

First, as the material for the deep drawing container, any material can be used as long as it can be formed by deep drawing and can be sealed by heat sealing with a lid (hereinafter referred to as heat sealing). For example, a single sheet of polyethylene (PE), polypropylene (PP), polystyrene (PS) or the like, or a multilayer sheet thereof may be used.

[0008] Mushrooms have a low oxygen concentration and produce odors such as alcohol smell when anaerobic respiration is caused. In addition, when a large amount of oxygen is present, discoloration such as browning occurs, aerial mycelia is formed, or Stretch and deform. Therefore, in order to maintain the freshness of the mushroom, it is necessary to maintain the oxygen concentration in the container at a minimum oxygen concentration that does not cause anaerobic respiration. That is, it is necessary to supply sufficient oxygen necessary for breathing, and to keep the equilibrium oxygen concentration in the container at about 5% or less. For this purpose, it is necessary to package mushrooms with a packaging material that has sufficient oxygen permeability to supply oxygen.However, in deep-drawing packaging, it is almost impossible to supply oxygen from a deep-drawing container. Need to supply. In this case, the effective area of the packaging material involved in the supply of oxygen is significantly smaller than that in the bag packaging, so that the oxygen permeability required for the packaging material is higher than in the case of maintaining the freshness of the fruits and vegetables described above. That is, the oxygen permeability of the lid material required for maintaining the freshness of the mushroom varies depending on the type, the internal capacity, the container size, and the storage temperature of the mushroom. In most cases, the oxygen permeability at the storage temperature is 20%. ,
000-100,000cm ³ / m ² · 24hr · at
m.

As such a lid material, a film having the above-mentioned oxygen permeability, such as a multilayer film having two or more layers whose innermost layer is a resin capable of being heat-sealed with a deep drawing container, for example,
Stretched PP (OPP) / Low density PE (LDPE), OPP
/ A film obtained by processing a general-purpose film such as unstretched PP (CPP) so as to have a necessary oxygen permeability can be used. The film that can be used as the lid material is not limited to these, and is a film that can be heat-sealed with a deep-drawn container, has the above-mentioned oxygen permeability necessary for maintaining the freshness of mushrooms, and has suitability for packaging machinery. If it does, a film of any configuration can be used, for example, a single-layer film. That is, the type of lid material that can be used is limited only by the material of the deep drawn container, the oxygen permeability of the lid material, and the suitability of the packaging machine.

When a general-purpose film as described above is used as a cover material, the oxygen permeability of the general-purpose film is generally 3,0.
Because it is less than 00 cm ³ / m ² · 24 hr · atm,
It must be processed to have the required oxygen permeability.
As a processing means, a method of opening a film with a hot needle or a laser is also possible, but the hole diameter is as large as 100 μm or more, and the oxygen permeability is too high and control is difficult. Therefore, the pore size is several μm from either side of the film.
A preferred method is to form a large number of through-holes and non-penetrating micropores having a size of from several tens to several tens of micrometers, and to obtain the necessary oxygen permeability by controlling the number, depth, and size of the pores. As a method of forming the fine holes, JP-A-4-2499 and JP-A-5-38
The method described in Japanese Patent Publication No. 765 may be used. That is, a method in which fine diamond particles are provided on a roll, and a film is passed between the roll and the opposite roll to form fine holes.

As shown in FIG. 1, in the cover material 1 opened in this manner, in most cases, both the through-holes 4 and the non-through-holes 5 are formed, and the ratio is 0 to 0 depending on the oxygen permeability. 1
It varies within the range of 00%, and the higher the oxygen permeability, the higher the ratio of through holes. In addition, the through-hole referred to here includes not only the complete through-hole 4 but also a through-hole 5 in which a crack 7 is formed in the film remaining portion 6 of the non-through-hole 5 and both sides of the film are connected.

In order to maintain the freshness of mushrooms using the above-described deep-drawing container and the lid material, the mushroom is filled in the deep-drawing container, and the mushroom necessary for the mushroom is determined from the container shape and the filling amount. The container may be completely sealed by heat sealing with a lid having oxygen permeability. However, in the normal temperature range, mushrooms cannot be stored for a long time, regardless of the storage method. Therefore, the effect of maintaining the freshness of mushrooms by the packaging material of the present invention is not significant unless the mushrooms are stored and distributed at a low temperature, that is, 15 ° C. or lower. However, if the temperature is too low, there is a risk of partial freezing due to temperature variations in the storage, so the set temperature is preferably 5 ° C. or higher.

Also, by using a deep drawing container,
Even if the containers are stacked during transportation or sale, no load is applied to the mushrooms in the containers, and the mushrooms can be prevented from being damaged by the load. However, it is conceivable that mushrooms move in the container due to vibration during transportation or the like and collide with the inner wall of the container or the like to be damaged. Therefore, in the case of mushrooms, such as shimeji and enoki, which are in one lump and the sizes of the strains are relatively uniform, deep-drawing containers such as deep-drawn containers in the case of enoki having the shape shown in FIG. 2 are used. By shaping the shape of the squeezed container 10 into substantially the same shape as those mushrooms, filling the container 10 with mushrooms, and sealing with a lid material, the movement of the mushrooms in the container can be prevented, so that the mushroom is not damaged. it can. Further, the deep-drawn container is softer than the tray and can be easily crushed, so that it is not bulky at the time of disposal and does not cause any problem.

[0014]

The packaging material of the present invention comprises a deep-drawing container and a lid member of a plastic film which is heat-sealed at the flange of the container, and the lid member has a thickness of 20,000 to 100,000 cm ^3.
/ M ² · 24 hr · atm, so that packaging of this packaging mushroom keeps its freshness, and at the same time, because it is a deep drawn container, the mushrooms in the container can be stacked even when stacked. Is not damaged by the load, and disposal of the container after use becomes easy. Further, by making the shape of the container substantially the same as that of the mushroom, damage during transportation can be prevented. Further, by setting the storage temperature in the range of 5 ° C. to 15 ° C., the effect is remarkable.

[0015]

Examples of the present invention will be described below. <Example 1> A packaging material according to an example of the present invention has a top opening obtained by deep drawing of a 500 μm-thick PP sheet as shown in FIG.
0 mm rectangular parallelepiped deep drawing container 10 and, as shown in FIG.
OPP layer 2 having a thickness of 20 μm and CPP having a thickness of 25 μm
The cover material 1 is obtained by forming micropores 4 and 5 having a pore diameter of several μm to several tens μm from the CPP layer side on the two-layer film of the layer 3. The micropores of the lidding film are formed by passing between the rollers having diamond particles coated on one surface of a pressure roller, and the oxygen permeability is 80,000 cm ³ at 15 ° C.
/ M ² · 24 hr · atm.

Embodiment 2 A packaging material according to an embodiment of the present invention has a 150 mm thick upper opening obtained by deep drawing a PS / PE sheet having a thickness of 350 μm as shown in FIG.
× 80 mm, a deep drawing container 10 shaped to an enoki having a maximum depth of 60 mm, and as shown in FIG. 1, a two-layer film composed of an OPP layer 2 and an LDPE layer 3 each having a thickness of 20 μm, and an LDPE layer. The lid 1 is obtained by forming micro holes 4 and 5 having a hole diameter of several μm to several tens μm from the side. The fine pores of the lidding film are formed by passing between the rollers having one surface of a nip roller coated with diamond particles, and have an oxygen permeability of 40,000 cm ³ / m ² at 5 ° C.
It is adjusted to 4 hr · atm.

Example 3 A packaging material according to an example of the present invention has a top opening obtained by deep drawing a PS / PE sheet having a thickness of 400 μm as shown in FIG.
× 150mm, bottom 50mm × 80mm, depth 70m
1 is a 200 mm × 150 mm deep drawing container 10 in which two containers each having a trapezoidal cross-sectional shape are connected to each other.
As shown in the figure, the OPP layer 3 in which the thickness of each layer is 20 μm
And a lid material 1 obtained by forming micropores 4 and 5 having a pore diameter of several μm to several tens μm from the OPP layer side in a two-layer film composed of the LDPE layer 2 and The fine pores of the lid material film are formed by passing between the rollers having one surface of a pressure roller coated with diamond particles, and have an oxygen permeability of 6 at 10 ° C.
It was adjusted to 000 cm ³ / m ² · 24 hr · atm.

<Comparative Example 1> A packaging material as a comparative example of the present invention has the same deep drawing container 10 as in Example 1 and the same structure as in Example 1 and has fine pores having a pore diameter of several μm to several tens μm from the CPP layer side. 4,
5 and a cover material 1 whose oxygen permeability was adjusted to 10,000 and 150,000 cm ³ / m ² · 24 hr · atm at 15 ° C.

<Comparative Example 2> A packaging material as a comparative example of the present invention has the same deep drawing container 10 as in Example 2 and the same fine structure as that of Example 2 and has a fine hole having a hole diameter of several μm to several tens μm from the LDPE layer side. 4 and 5 and a lid material 1 whose oxygen permeability was adjusted to 10,000 and 100,000 cm ³ / m ² · 24 hr · atm at 5 ° C.

<Comparative Example 3> A packaging material as a comparative example of the present invention has the same deep drawing container 10 as in Example 3 and the same structure as in Example 3 and has fine pores having a pore diameter of several μm to several tens μm from the OPP layer side. 4,
5 and a cover material 1 whose oxygen permeability was adjusted to 10,000 and 120,000 cm ³ / m ² · 24 hr · atm at 10 ° C.

Example 4 and Comparative Example 4 150 g of shiitake mushrooms were filled in the deep-drawing containers 10 of Example 1 and Comparative Example 1 and sealed with the lid 1 of Example 1 and Comparative Example 1, respectively. After storage at 20 ° C., the state of shiitake mushrooms was observed over time. The number of samples was 10 under each condition.
The storage results are shown in (Table 1). In the examples, the freshness retention days could be made longer than any of the comparative examples.

[0022]

[Table 1]

<Example 5 and Comparative Example 5> The deep-drawn containers 10 of Example 2 and Comparative Example 2 were filled with 150 g of one strain of Enoki, and sealed with the lid 1 of Example 2 and Comparative Example 2, respectively. It was stored at 5 ° C and 20 ° C, and the state of the enokike was observed over time. The number of samples was 10 under each condition.
The storage results are shown in (Table 2). In the examples, the freshness retention days could be made longer than any of the comparative examples.

[0024]

[Table 2]

<Example 6 and Comparative Example 6> The deep-drawing containers 10 of Example 3 and Comparative Example 3 were filled with 150 g of two strains of Shimeji, and sealed with the lid 1 of Example 3 and Comparative Example 3, respectively. After storage at 10 ° C. and 20 ° C., the state of shimeji was observed over time. The number of samples was 10 under each condition.
The storage results are shown in (Table 3). In the examples, the freshness retention days could be made longer than any of the comparative examples.

[0026]

[Table 3]

[0027]

The packaging material of the present invention uses a deep drawing container.
Preferably, the shape of the container should be substantially the same as that of the mushroom, and the lid material
Use a film whose oxygen permeability can be controlled.
The oxygen permeability of the wood is most important for keeping the mushrooms fresh.
Proper transparency increases content protection,
Stacking during transportation is also possible, and mushroom
The effect of maintaining freshness is also exhibited.
It is not too bulky. Further, the method for maintaining freshness of the present invention
If used, the synergistic effect of keeping the packaging material fresh and preserving it at low temperatures
As a result, it is possible to maintain the freshness of mushrooms more than before.
Wear. In the examples, the oxygen permeability of the lid material is set at the storage temperature.
40,000-80,000cm ^Three/ M^Two・ 24
hr · atm, but actually the effective area and contents of the lid material
20,000-100,000c depending on quantity, storage temperature, etc.
m^Three/ M^Two・ It is necessary to control within the range of 24hr ・ atm
Yes, exceptionally 100,000cm^Three/ M^Two・ 24hr
・ May require oxygen permeability of atm or more
You. The present invention provides a mushroom freshness-keeping packaging material and the packaging material.
Regarding the method of maintaining freshness used,
Even for fruits and vegetables such as grass and asparagus, the oxygen in the lid material
It can be applied simply by changing the range of transmittance.

[0028]

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view showing one embodiment of a plastic film lid material used as a packaging material of the present invention.

FIG. 2 is a perspective view of a deep drawing container of a freshness holding packaging material for enoki, showing an embodiment of the packaging material of the present invention.

FIG. 3 is a perspective view showing an embodiment of the deep-drawing container for packaging material of the present invention.

FIG. 4 is an explanatory cross-sectional view of a deep-drawing container of a freshness retaining packaging material for shimeji, showing an embodiment of the packaging material of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Lid material (multilayer film) 2 ... Non-opening side resin layer 3 ...
Opening side resin layer 4 ... Through hole 5 ... Not through hole 6 ... Film remaining part 7 ... Crack 10 ... Deep drawing container

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takeo Tomatsuri 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (56) References JP-A-1-309621 (JP, A) JP-A-5 JP-A-316943 (JP, A) JP-A-1-171434 (JP, A) JP-A-5-153907 (JP, A) JP-A-6-205656 (JP, A) JP-A-7-87884 (JP, A) JP-A-4-339765 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A23B 7/00 A23B 7/148 B65D 65/40 B65D 81/26 B65D 85/50 B32B 3 / 26-3/30 B32B 27/00-27/42

Claims (2)

(57) [Claims] 1. A shimeji mushroom having a flange portion and being a content
Or a deep drawing container that is almost the same shape as the enoki mushroom mass
Plastic filler heat-sealed at the flange of the container
Plastic material for the packaging material
At the storage temperature of shimeji mushrooms or enoki mushrooms
20,000 to 100,0 in the range of 5 ° C to 15 ° C
Oxygen permeability of 00cm ³ / m ² · 24hr · atm
And a multi-layered filter with two or more
And a pore diameter of several μm to several tens from one of the surfaces.
μm penetrating and non-penetrating micropores
Characteristic freshness preserving packaging material for mushrooms. 2. Distribution and storage using the packaging material according to claim 1.
Shimeji mushrooms or enoki at temperatures ranging from 5 ° C to 15 ° C
Maintaining the freshness of mushrooms, keeping mushrooms fresh
Holding method.