JP2018076081A - Freshness-keeping packaging bag for bean sprout or fungi, packaging body containing bean sprout or fungus and method for maintaining freshness of sprout or fungus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging technique capable of maintaining the freshness of bean sprouts or fungi mushrooms for a long period of time while maintaining the appearance of a package. SOLUTION: The freshness-preserving packaging bag for sprouts or fungi used for accommodating sprouts or fungi as contents, the packaging bag is made of a synthetic resin film, and 23 of the synthetic resin film. The oxygen permeation amount at 60 ° C. and 60% RH is 1500 cc / m2 · day · atm or more and 7,000 cc / m2 · day · atm or less, and the elastic coefficient of the synthetic resin film at 23 ° C. is 150 MPa or more and 1600 MPa or less. [Selection diagram] None

Description

  The present invention relates to a freshness-keeping packaging bag for bean sprout or fungi, a package containing bean sprout or fungus and a method for maintaining freshness of bean sprout or fungus.

Fruits and vegetables such as bean sprouts and fungi may be distributed to the market after harvesting in a deaerated package in a packaging bag made of a synthetic resin film.
And about the structure of the synthetic resin film which comprises the packaging bag mentioned above, from the viewpoint of improving so that the freshness of the sprouts and fungi which are contained can be maintained for a long period of time, various examinations have been made so far. .

  For example, Patent Document 1 uses a film in which an easily heat-sealable resin layer containing zinc oxide fine particles and stretched in at least one axial direction is laminated on one side of a biaxially stretched polypropylene base layer, A technique for packaging bean sprouts is disclosed.

  For example, Patent Document 2 discloses a technique for packaging mushrooms using a synthetic resin film provided with a non-through vent hole for setting the air flow rate of a film material to a required value.

JP 2003-25524 A JP-A-6-329162

  However, if the harvested bean sprouts and fungi are used as the contents, and the package is formed by degassing and packaging the contents using conventional packaging technology, the time elapsed after the contents are packaged. Along with this, there are cases in which the package body slightly swells, the packaged contents are discolored (brown), or a strange odor is generated from the packaged contents.

  Based on the above, the present invention provides a packaging technique capable of maintaining the freshness of sprouts or fungi for a long period of time while maintaining the appearance of the package.

According to the present invention, it is a freshness-keeping packaging bag for bean sprout or fungi that is used to contain bean sprout or fungi as a content,
The packaging bag is made of a synthetic resin film,
The synthetic resin film has an oxygen transmission amount at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm,
There is provided a freshness-keeping packaging bag for bean sprout or fungi whose elastic modulus at 23 ° C. of the synthetic resin film is 150 MPa or more and 1600 MPa or less.

Further, according to the present invention, a bean sprout or fungus-containing package, in which bean sprouts or fungi are contained as contents in the internal space of the packaging bag made of a synthetic resin film in a deaerated state, ,
The synthetic resin film has an oxygen transmission amount at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm,
Provided is a bean sprout or fungus-containing package having an elastic modulus at 23 ° C. of the synthetic resin film of 150 MPa to 1600 MPa.

Furthermore, according to the present invention, in the internal space of the packaging bag made of a synthetic resin film, the step of containing sprouts or fungi as contents,
Obtaining a bean sprouts or fungus-containing package by sealing the packaging bag while degassing,
Including
The synthetic resin film has an oxygen transmission rate at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm, and the elastic modulus at 23 ° C. of the synthetic resin film is 150 MPa to 1600 MPa. A method for maintaining the freshness of bean sprouts or fungi that is adjusted to be as follows is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the packaging technique which can maintain the freshness of a sprouts or fungi is maintained for a long time, maintaining the external appearance of a package.

<Freshness-keeping packaging bag for bean sprouts or fungi>
The bean sprouts or fungi freshness-keeping packaging bag (hereinafter also referred to as this packaging bag) according to the present embodiment is used to contain bean sprouts or fungi as contents, and is made from a synthetic resin film. Is adopted. In particular, the present packaging bag can be suitably used for distribution in the market in a state where the contents are contained in the internal space of the packaging bag made of a synthetic resin film in a deaerated state.
And this packaging bag is further characterized by employ | adopting the structure which satisfy | fills the following two conditions. As a result, when producing a package containing the bean sprouts or fungi in the inner space of the packaging bag as the contents, the freshness of the contents is maintained for a long time while maintaining the appearance of the package. It becomes possible to do.
The first condition is that the oxygen permeation amount at 23 ° C. and 60% RH of the synthetic resin film constituting the packaging bag is 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm. .
The second condition is that the elastic modulus at 23 ° C. of the synthetic resin film constituting the packaging bag is 150 MPa or more and 1600 MPa or less.

Here, fruits and vegetables such as bean sprouts and fungi, which can be used as contents to which the present packaging bag can be applied, continue to breathe even after harvesting. Therefore, during storage, distribution or preservation after harvesting, energy is consumed by respiration of the content itself, resulting in deterioration of freshness of the content.
In general, in order to maintain the freshness of the contents according to the present embodiment, such as bean sprouts and fungi, the respiration rate of the contents and a packaging material used for packaging the contents such as a synthetic resin film, for example. It is said that it is effective to make the package have a low oxygen concentration and a high carbon dioxide concentration state according to the balance of the gas permeation amount.

  Here, in the present embodiment, the fungi mentioned above include enokitake, eringi, jellyfish, kinagasatake, shiitake, shimeji, white jellyfish, tamogitake, chichitake, nameko, aratake, scallop, oyster mushroom, bunshimeji, porcini, honshige, Examples include mushrooms, matsutake, and yamabushitake. Of these, enokitake, eringi, shiitake, shimeji and maitake are preferred from the viewpoint of versatility. Moreover, the fungi mentioned above may be in a cut state, that is, in the form of so-called cut vegetables.

In addition to the balance between the respiration rate of sprouts or fungi and the gas permeation performance of the synthetic resin film constituting the packaging bag, this packaging bag controlled the mechanical strength of the synthetic resin film constituting the packaging bag. Is. Thereby, according to this packaging bag, when producing a package body containing bean sprouts or fungi as contents in the interior space of the packaging bag, various gas concentration conditions existing in the package body are set. It becomes possible to control at a high level compared with the conventional method. Furthermore, according to this packaging bag, the time elapsed since the contents were packaged under the influence of the breathing performed by the contained contents themselves while storing, distributing or preserving the above-mentioned package. Accordingly, it is possible to effectively suppress the inconvenience that the package body swells.
Specifically, as described above, the present packaging bag is combined with the oxygen transmission amount (hereinafter referred to as oxygen transmission amount Tx) at 23 ° C. and 60% RH of the synthetic resin film constituting the packaging bag. The gas permeability and mechanical strength of the synthetic resin film are controlled so that the elastic modulus at 23 ° C. of the resin film shows a predetermined value. For this reason, according to this packaging bag, the following effects are acquired.
1stly, according to this packaging bag, when the packaging body which contains a bean sprout or fungi as a content in the interior space of this packaging bag is produced, the content is an oxygen deficiency (oxygen deficiency state) It is possible to prevent the gas concentration condition in the package from becoming excessive oxygen. As a result, the freshness of the sprouts and fungi that are the contents can be stably maintained for a long period of time.
Secondly, according to the present packaging bag, bean sprout or fungi are stored as contents in the inner space of the packaging bag, and the storage time of the package obtained by sealing the packaging bag elapses. As a result, an increase in the oxygen concentration in the package can be suppressed. Therefore, when the packaging body is stored, it is possible to effectively suppress an increase in the respiration rate of the contents described above, and as a result, the packaging body with the storage time elapses. In the point that it can suppress that a body swells, the external appearance (appearance) of a package can be kept for a long time in a good state.
Thirdly, according to the present packaging bag, bean sprouts or fungi are stored as contents in the interior space of the packaging bag, and the packaging itself obtained by sealing the packaging bag is stored with the contents itself. It can suppress that the synthetic resin film which comprises this packaging bag stretches under the influence by the gas component produced by respiration performed. Therefore, when the packaging body is stored, it is possible to effectively suppress the swelling of the packaging body as the storage time of the packaging body elapses. As a result, the appearance (appearance of the packaging body) ) Can be kept in good condition for a long time.

  Hereinafter, the structure of this packaging bag is demonstrated in detail. In the following description, a package in which bean sprouts or fungi are hermetically contained in the interior space of the packaging bag as a content is referred to as the present package, and bean sprouts or fungi are described above. The contents will be referred to as follows.

In this embodiment, the lower limit value of the oxygen transmission rate Tx at 23 ° C. and 60% RH of the synthetic resin film constituting the packaging bag is 1500 cc / m ² · day · atm or more, preferably 1800 cc / m ^2. Day · atm or more, more preferably 2200 cc / m ² · day · atm or more, particularly preferably 2400 cc / m ² · day · atm or more, most preferably 2500 cc / m ² · day.・ Atm or higher. As described above, when the oxygen permeation amount Tx of the synthetic resin film is controlled to be equal to or higher than the lower limit value, it is possible to prevent the contents in the package from becoming oxygen deficient (oxygen deficient state). As described above, the freshness of the contents can be stably maintained for a long time.

On the other hand, in this embodiment, the upper limit value of the oxygen transmission amount Tx at 23 ° C. and 60% RH of the synthetic resin film is 7000 cc / m ² · day · atm or less, preferably 6800 cc / m ² · day · atm. Or less, more preferably 6500 cc / m ² · day · atm or less, and most preferably 5000 cc / m ² · day · atm or less. Thus, when the oxygen permeation amount Tx of the synthetic resin film is controlled to be equal to or lower than the above upper limit value, it is possible to prevent the gas concentration condition in the package from becoming excessive oxygen. It is possible to maintain the freshness of the contents stably for a long time while maintaining the appearance of the body.

In the present embodiment, the lower limit value of the oxygen permeation amount T1 per 100 g of the content of the synthetic resin film at 23 ° C. and 60% RH is preferably 600 cc / 100 g · m ² · day · atm or more. Preferably, it is 720 cc / 100 g · m ² · day · atm or more, more preferably 880 cc / 100 g · m ² · day · atm or more, most preferably 960 cc / 100 g · m ² · day · atm or more. It is. As described above, when the oxygen transmission amount T1 per 100 g of the content of the synthetic resin film is controlled to be equal to or higher than the lower limit, the appearance of the package and the freshness of the content can be maintained in a balanced manner. it can.

On the other hand, the upper limit value of the oxygen permeation amount T1 per 100 g of the content of the synthetic resin film at 23 ° C. and 60% RH is preferably 4098 cc / 100 g · m ² · day · atm or less, more preferably 3980 cc / 100 g · m ² · day · atm or less, more preferably 3805 cc / 100 g · m ² · day · atm or less, and most preferably 2927 cc / 100 g · m ² · day · atm or less. As described above, when the oxygen transmission amount T1 per 100 g of the content of the synthetic resin film is controlled to be equal to or less than the upper limit, as a result, the freshness of the content is maintained for a long time while maintaining the appearance of the package. It can be maintained stably.

  In the present embodiment, the lower limit value of the oxygen permeation amount To per 100 g of the content at 23 ° C. and 60% RH of the package is preferably 47 cc / 100 g · day · atm or more, more preferably the content. From the viewpoint of suppressing the generation of off-flavors in the product, it is 57 cc / 100 g · day · atm or more, more preferably 62 cc / 100 g · day · atm from the viewpoint of suppressing the appearance of the package from changing. More preferably, it is 70 cc / 100 g · day · atm or more, and most preferably 80 cc / 100 g · day · atm from the viewpoint of maintaining a good balance between the appearance of the package and the freshness of the contents. That's it. Thus, when the oxygen permeation amount To per 100 g of bean sprouts of the present package is controlled to be equal to or higher than the lower limit, the contents are accommodated in the present package without oxygen deficiency (oxygen deficient state). It is possible to suppress an increase in the respiration rate of the contents over time after the contents are packaged. Therefore, when the oxygen permeation amount To per 100 g of the contents of the package is controlled to be equal to or higher than the lower limit, as a result, the freshness of the contents is stably maintained for a long time while maintaining the appearance of the package. Can be maintained.

  On the other hand, in this embodiment, the upper limit value of the oxygen permeation amount To per 100 g of contents at 23 ° C. and 60% RH of the present package is preferably 426 cc / 100 g · day · atm or less, more preferably From the viewpoint of suppressing the appearance of the package from changing, it is 414 cc / 100 g · day · atm or less, and more preferably, from the viewpoint of suppressing discoloration (browning) in the contents, 396 cc / 100 g It is not more than day · atm, and particularly preferably not more than 304 cc / 100 g · day · atm from the viewpoint of maintaining a good balance between the appearance of the package and the freshness of the contents. As described above, when the oxygen transmission amount To per 100 g of the contents of the package is controlled to be equal to or less than the upper limit, as a result, the freshness of the contents is maintained for a long time while maintaining the appearance of the package. It becomes possible to maintain it stably.

Oxygen permeation amount Tx at 23 ° C. and 60% RH of the synthetic resin film described above, oxygen permeation amount T1 per 100 g of the content at 23 ° C. and 60% RH of the synthetic resin film, and 23 ° C. and 60% of the package body The oxygen transmission amount To per 100 g of contents in RH can be calculated by the following methods, respectively. First, an oxygen transmission rate Tx [cc / m ² · day · atm] at 23 ° C. and 60% RH of a synthetic resin film was measured using an oxygen transmission rate measuring device (Oxytran (registered trademark) OX-TRAN manufactured by MOCON). 2/21) and is measured by a method based on Annex B in JIS K7126-2.
Next, the measurement value related to the oxygen transmission amount Tx [cc / m ² · day · atm] of the synthetic resin film obtained by the above-described method was calculated by dividing by the weight of the contents contained in the packaging bag. Multiply the value by 100. By carrying out like this, oxygen permeation amount T1 [cc / 100g * m < ² > * day * atm] per 100g of contents in the synthetic resin film concerning this embodiment in 23 degreeC and 60% RH is computable.
Next, the inner surface area [m ² ] of the package is set to the value of oxygen permeation amount T1 [cc / 100 g · m ² · day · atm] per 100 g of the content of the synthetic resin film at 23 ° C. and 60% RH. The oxygen transmission amount To [cc / 100 g · day · atm] per 100 g of the contents of the package at 23 ° C. and 60% RH can be calculated.

In the present embodiment, the lower limit value of the elastic modulus at 23 ° C. of the synthetic resin film is 150 MPa or more, preferably 160 MPa or more, more preferably 170 MPa or more, and further preferably 180 MPa or more. It is. By carrying out like this, it becomes possible to hold | maintain with good balance the external appearance of this package body, and the freshness of the contents. On the other hand, the upper limit of the elastic modulus at 23 ° C. of the synthetic resin film is 1600 MPa or less, preferably 1400 MPa or less, and more preferably 1000 MPa or less. In this way, since the packaging bag can be provided with appropriate flexibility, when the contents such as bean sprout and fungi are contained in the present packaging bag to produce the above-described packaging body, A desired package can be produced with good yield without depending on the shape or the like, and further, the appearance change of the finally obtained package can be suppressed.
In addition, the elasticity modulus in 23 degreeC of the synthetic resin film mentioned above can be measured by the method based on JISK7127, for example.

In addition, the contact angle of water with respect to the surface constituting the side of the package in which the contents are accommodated, that is, the inner surface of the package bag is preferably 3 ° or more and 60 ° or less, more preferably It is 5 ° or more and 55 ° or less, more preferably 10 ° or more and 50 ° or less, and most preferably 10 ° or more and 30 ° or less. By carrying out like this, it can suppress that dew condensation generate | occur | produces on the inner surface of this package by the trace amount water vapor | steam released from the contents in this package.
In addition, as a method for measuring the contact angle of water, for example, a commercially available contact angle meter such as DROPMASTER-501 manufactured by Kyowa Interface Science Co., Ltd. is used. There is a method of measuring the contact angle by a liquid suitable method.

  Moreover, the haze value of the synthetic resin film which comprises this packaging bag becomes like this. Preferably it is 20% or less, More preferably, it is 10% or less, More preferably, it is 6% or less. By carrying out like this, this packaging body can be made into the thing excellent in appearance from a viewpoint that it is excellent in internal visibility. On the other hand, the lower limit value of the Haze value is not particularly limited and is preferably closer to 0%. In addition, the said Haze value can be measured by the method based on JIS-K-7136.

  In addition, the amount of the contents accommodated in the internal space of the packaging bag is preferably 150 g or more and 350 g or less per package, for example, from the viewpoint of improving consumer demand and manufacturing cost balance.

  Next, the synthetic resin film which comprises this packaging bag is demonstrated.

The material constituting the synthetic resin film can be used for the packaging of bean sprout and fungi, and the gas permeability and mechanical strength of the synthetic resin film are controlled so as to satisfy the above-mentioned conditions. If it can do, it will not be limited. Specific examples of the material constituting the synthetic resin film include polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin, propylene-1-butene copolymer, and the like. These may be homopolymers, copolymers, or blends containing two or more of these homopolymers and copolymers. That is, the synthetic resin film in the present embodiment has a resin layer containing one or more resins selected from the group consisting of polyethylene, polypropylene, polystyrene, and ethylene-vinyl acetate copolymer resin among various resin materials. It is preferable that Moreover, in this embodiment, it is preferable that this resin layer contains an antifogging agent. By carrying out like this, it can suppress that dew condensation generate | occur | produces on the inner surface of this package by the trace amount water vapor | steam released | released from the content accommodated in this packaging bag.
In this embodiment, when the synthetic resin film has the resin layer containing the antifogging agent, the content of the antifogging agent relative to the total amount of the resin layer balances the appearance of the package and the freshness of the contents. From the standpoint of maintaining well, it is preferably 0.1% by weight or more and 5% by weight or less, and more preferably 0.3% by weight or more and 2.5% by weight or less.

  In the present embodiment, as the antifogging agent, any known antifogging agent such as a fatty acid ester of a polyhydric alcohol or an ethylene oxide adduct of a higher aliphatic amine can be used. Specific examples thereof include glycerin monostearate, diglycerin laurate, decaglycerin laurate, and sorbitan stearate.

  Further, in the present embodiment, the melting point of the resin exemplified above constituting the synthetic resin film is preferably 75 ° C. or more and 170 ° C. or less, more preferably, from the viewpoint of improving the production efficiency of the packaging bag. It is 75 degreeC or more and 165 degrees C or less, More preferably, it is 85 degreeC or more and 160 degrees C or less.

  Further, the synthetic resin film according to the present embodiment may be a stretched film or an unstretched film, but the respiration rate of contents such as sprouts and fungi and the gas permeation rate of the synthetic resin film From the viewpoint of highly controlling the balance of the film, an unstretched film is preferable. Further, when the synthetic resin film is a stretched film, from the viewpoint of highly controlling the balance between the respiration rate of the contents and the gas permeation amount of the synthetic resin film, the longitudinal direction (MD direction) and the width direction ( It is preferable that the stretching process is performed 5 times or less in both directions (TD direction).

  In addition, the synthetic resin film according to the present embodiment may be a single layer film formed of the above-described material, or may be a multilayer film in which a plurality of layers are laminated in the thickness direction. Here, when the synthetic resin film according to the present embodiment is the multilayer film, the film is condensed on the inner surface of the package due to a small amount of water vapor released from the contents contained in the package bag. It is preferable to have the above resin layer containing an antifogging agent on at least one surface from the viewpoint of suppressing the occurrence of fog, and from the viewpoint of improving the production efficiency of the present packaging body, an antifogging agent is provided on both surfaces. It is more preferable that the resin layer is included. In addition, when the synthetic resin film according to the present embodiment is a multilayer film having a laminated structure in which three or more layers are laminated in the thickness direction, both surfaces of the multilayer film are used for the purpose of stabilizing the anti-fogging property of the packaging bag. An antifogging agent may be contained in a layer other than the two outermost layers constituting the layer.

  The layer structure of the synthetic resin film according to the present embodiment is such that, for example, in the thickness direction of the film, the resin layer containing the antifogging agent, the intermediate layer, and the resin layer containing the antifogging agent are in this order. You may have a laminated structure of three or more layers laminated by. In this case, the intermediate layer is not limited to a single layer structure, and may be a multilayer structure in which two or more layers are stacked in the thickness direction. Further, the outermost layer of the film is not limited to the resin layer containing an antifogging agent.

  The thickness of the synthetic resin film according to the present embodiment may be, for example, 20 μm or more and 40 μm or less. If the film is too thin, the strength may be insufficient. On the other hand, if the film is too thick, the production cost increases, so the practicality decreases.

  Moreover, in order to adjust the gas permeation | transmission amount, the fine hole may be drilled in the synthetic resin film which concerns on this embodiment. However, the synthetic resin film according to the present embodiment is fine from the viewpoint of suppressing the appearance of the packaging body from slightly changing with the passage of time after the contents are packaged. It is preferable that the hole is not perforated.

  As a method for molding the synthetic resin film, techniques such as an extrusion method (T-die method, inflation method) and a calendering method can be employed. When the film is formed, additives such as an antifogging agent may be kneaded as necessary, or two or more kinds of resins may be blended. Further, the film may be stretched or annealed. These films may be provided with a sealant layer, or may be a film coated to give some function.

Here, in the method for producing a bean sprouts or freshness-keeping packaging bag for fungi according to this embodiment, it is particularly important to highly control various factors related to the following three conditions. That is, this packaging bag can be produced for the first time by adopting a manufacturing method that highly controls various factors relating to the following three conditions. In addition, the manufacturing method of the bean sprouts or the freshness-keeping packaging bag for fungi according to the present embodiment can be achieved by combining other known manufacturing conditions as long as various factors related to the following three conditions are controlled to a high degree. Can be produced.
(1) Combination of resin materials used to form a synthetic resin film (2) Combination of layer structure and film forming method of synthetic resin film (3) Heat seal processing conditions of synthetic resin film

Hereinafter, an example of the manufacturing method of this packaging bag is demonstrated on the assumption that the various factors concerning the above three conditions are highly controlled.
First, a synthetic resin film is prepared. Next, after the synthetic resin film is cut out to a desired size, the two films are overlapped and heat sealed in three directions using a sealer to form a 10 mm wide heat sealed portion, thereby providing a packaging bag. Is made. By carrying out like this, this packaging bag can be obtained.

<Packaged bean sprouts or fungi>
The bean sprout or fungus-containing package according to the present embodiment is one in which bean sprout or fungus is contained in the inner space of a packaging bag made of a synthetic resin film in a deaerated state. That is, the bean sprout or fungus-containing package according to the present embodiment is one in which the bean sprout or fungus is contained in the interior space of the packaging bag described above.

Next, the manufacturing method of this package is demonstrated.
As a manufacturing method of this package, there exist the following methods, for example.
First, the packaging bag produced by the method described above is prepared. Next, a predetermined amount of contents are stored in the internal space of the packaging bag. Then, using a degassing sealer, while degassing the air present in the inner space of the packaging bag, heat sealing is applied to one of the packaging bags that has not yet been heat sealed, A heat seal portion is formed to obtain the package. Moreover, in this embodiment, the deaeration method of the interior space of a packaging bag is not limited to the method using the deaeration sealer mentioned above, A well-known method is employable.

<How to keep bean sprouts or fungi>
The method for maintaining the freshness of bean sprouts or fungi according to the present embodiment is a method for preserving sprouts or fungi using the packaging bag described above. Specifically, the method for maintaining the freshness of bean sprouts or fungi according to the present embodiment includes the step of storing bean sprouts or fungi as the contents in the inner space of the packaging bag described above, and the removal of the packaging bag. And obtaining a bean sprouts or fungus-containing package by sealing with air. By carrying out like this, the freshness of the bean sprouts and fungi which are the contents can be maintained for a long time, maintaining the appearance of the obtained package.

  As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.

  Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to these.

Example 1
First, a linear low density polyethylene resin (Prime Polymer Co., Ltd., Evolution SP3010, melting point: 124 ° C.) and an antifogging agent master batch (Riken Vitamin Co., Ltd., Riquet Master EAR-5, antifogging agent in a ratio of 12% by weight. The resin composition used for producing a synthetic resin film was prepared. At this time, both were mixed so that the content of the linear low density polyethylene resin with respect to the total amount of the resin composition was 90% by weight, and the content of the antifogging agent masterbatch with respect to the total amount of the resin composition was 10% by weight. .
Next, the prepared resin composition was charged into an air-cooled inflation coextrusion machine (Hokushin Sangyo Co., Ltd., HM55H type), and a synthetic resin film having a thickness of 30 μm was produced by an air-cooled inflation method. The obtained film was an endless film having no seam.
Next, after cutting out the obtained synthetic resin film to a predetermined size, heat seal processing is performed in three directions using an impulse sealer (manufactured by Fuji Impulse Co., Ltd., FI-400Y-10PK) to form a 10 mm wide heat seal portion. The packaging bag of Example 1 was obtained by forming.

  Next, using the resulting packaging bag, a bean sprouts package, a shimeji mushroom package, and a maitake mushroom package were prepared by the following method.

-Manufacturing method of package body containing bean sprout of Example 1 First, 210 g of mung bean sprouts was accommodated in the internal space of the obtained packaging bag (inner dimensions: 180 mm × 210 mm). Next, using a deaeration seal machine (V-301, manufactured by Fuji Impulse Co., Ltd.), while visually confirming that the internal space of the packaging bag is in a deaerated state, the remaining one of the packaging bag is 10 mm wide. By forming a heat-sealed portion, the bean-filled package of Example 1 was obtained. The inner surface area of the resulting bean sprouts packaged body was 7.2 × 10 ⁻² m ² .

-Production method of package containing shimeji of Example 1 Similarly, 180 g of shimeji was stored in the internal space of the obtained packaging bag (inner dimensions: 180 mm x 210 mm). Next, using a deaeration seal machine (V-301, manufactured by Fuji Impulse Co., Ltd.), while visually confirming that the internal space of the packaging bag is in a deaerated state, the remaining one of the packaging bag is 10 mm wide. By forming the heat-sealed portion, the shimeji-containing package of Example 1 was obtained. The inner surface area of the obtained shimeji-in package was 7.2 × 10 ⁻² m ² .

-Manufacturing method of the package containing maitake of Example 1 Similarly, maitake 180g was accommodated in the internal space of the obtained packaging bag (inside dimension: 180 mm x 210 mm). Next, using a deaeration seal machine (V-301, manufactured by Fuji Impulse Co., Ltd.), while visually confirming that the internal space of the packaging bag is in a deaerated state, the remaining one of the packaging bag is 10 mm wide. By forming the heat-sealed portion, the package containing maitake of Example 1 was obtained. The inner surface area of the obtained maitake-containing package was 7.2 × 10 ⁻² m ² .

(Example 2)
Instead of the linear low density polyethylene resin, a low density polyethylene resin (Sumitomo Chemical Co., Sumikasen F-218-0, melting point: 108 ° C.) is used, and the low density polyethylene resin and antifogging agent master batch (manufactured by Riken Vitamin Co., Ltd.) Synthetic resin film was prepared using a resin composition obtained by mixing Riquemaster EAR-5 and 12% by weight of antifogging agent), and the thickness was 40 μm. Except for the point that the resin film was formed, the sprout-containing package, the shimeji-containing package, and the maitake-containing package of Example 2 were obtained in the same manner as in Example 1. In addition, the inner surface area of the bean sprouts package, the shimeji mushroom package, and the mitake mushroom package of Example 2 was 7.2 × 10 ⁻² m ² . The content of the low density polyethylene resin relative to the total amount of the resin composition used for producing the synthetic resin film is 90% by weight, and the content of the antifogging agent master batch relative to the total amount of the resin composition is 10%. %Met.

(Example 3)
A high-density polyethylene resin (manufactured by Prime Polymer Co., Ltd., Hi-Zex 3300F, melting point: 132 ° C.) is used in place of the linear low-density polyethylene resin, and the high-density polyethylene resin and antifogging agent master batch (manufactured by Riken Vitamin Co., Ltd., Riquete Master EAR) Example 5 except that a synthetic resin film was prepared using a resin composition obtained by mixing -5 and an antifogging agent in a proportion of 12% by weight. 3 bean sprouts, shimeji mushroom and maitake mushroom. The inner surface area of the bean sprouts package, the shimeji mushroom package, and the mitake mushroom package of Example 3 was 7.2 × 10 ⁻² m ² . The content of the high-density polyethylene resin relative to the total amount of the resin composition used for producing the synthetic resin film is 90% by weight, and the content of the antifogging agent master batch relative to the total amount of the resin composition is 10%. %Met.

Example 4
First, polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., Nobrene FS2011DG3, melting point 1: 58 ° C.) and antifogging agent masterbatch (manufactured by Riken Vitamin Co., Ltd., Riquet Master PAR-380, containing 10% by weight of antifogging agent) The resin composition used in order to produce a synthetic resin film was prepared by mixing. At this time, both were mixed so that the content of the polypropylene resin with respect to the total amount of the resin composition was 88% by weight, and the content of the antifogging agent master batch with respect to the total amount of the resin composition was 12% by weight. Next, the prepared resin composition was put into a T-die extruder, and a synthetic resin film having a thickness of 25 μm was produced by a multi-manifold T-die method.
Next, after cutting out the obtained synthetic resin film into a predetermined size, the two films are superposed and heat-sealed in three directions using an impulse sealer (Fuji Impulse Co., Ltd., FI-400Y-10PK). The packaging bag of Example 4 was produced by forming a heat-sealed portion having a width of 10 mm.
Next, by using the obtained packaging bag, a bean sprouts package, a shimeji mushroom package, and a mitake mushroom package of Example 4 were produced in the same manner as in Example 1. In addition, the inner surface area of the bean sprouts package, the shimeji mushroom package, and the mitake mushroom package of Example 4 was 7.2 × 10 ⁻² m ² .

(Example 5)
A synthetic resin film having a thickness of 25 μm having a three-layer structure in which a resin layer, an intermediate layer, and a resin layer were laminated in this order in the thickness direction was produced by the following method.
First, polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., Nobrene FS2011DG3, melting point 1: 58 ° C.) and antifogging agent masterbatch (manufactured by Riken Vitamin Co., Ltd., Riquet Master PAR-380, containing 10% by weight of antifogging agent) And a propylene-1-butene copolymer (manufactured by Mitsui Chemicals, Tuffmer (registered trademark) XM7070) were mixed to prepare a resin composition used for preparing the resin layer. At this time, the content of the polypropylene resin with respect to the total amount of the resin composition was 78% by weight, the content of the antifogging agent masterbatch with respect to the total amount of the resin composition was 12% by weight, and the propylene-1-butene content relative to the total amount of the resin composition was Each raw material component was mixed so that the content of the polymer would be 10% by weight.
Moreover, as a material used in order to form the said intermediate | middle layer, the low density polyethylene resin (The Sumitomo Chemical Co., Ltd. make, Sumikasen F-218-0) was prepared.

Next, the resin composition used for producing the resin layer and the material used for forming the intermediate layer are put into a T-die extruder and subjected to a multi-manifold T-die method (co-extrusion T-die method). A synthetic resin film having a thickness of 25 μm having a three-layer structure in which a resin layer having a thickness of 5 μm, an intermediate layer having a thickness of 15 μm, and a resin layer having a thickness of 5 μm are laminated in this order in the thickness direction was produced. .
Next, after cutting out the obtained synthetic resin film into a predetermined size, the two films are superposed and heat-sealed in three directions using an impulse sealer (Fuji Impulse Co., Ltd., FI-400Y-10PK). The packaging bag of Example 5 was produced by forming a heat-sealed portion having a width of 10 mm.
Next, by using the obtained packaging bag, a bean sprouts package, a shimeji mushroom package, and a mitake mushroom package of Example 5 were produced in the same manner as in Example 1. In addition, the inner surface area of the bean sprouts package, the shimeji mushroom package, and the mitake mushroom package of Example 5 was 7.2 × 10 ⁻² m ² .

(Comparative Example 1)
An anti-fogging biaxially stretched polypropylene film (Toyobo Co., Ltd., Pyrene Film-OT: P5562) having a thickness of 25 μm was prepared as a synthetic resin film. Next, after cutting out such a synthetic resin film to a predetermined size, the two films are superposed and subjected to heat sealing processing on three sides using an impulse sealer (Fuji Impulse Corp., FI-400Y-10PK). A packaging bag of Comparative Example 1 was produced by forming a heat-sealed portion having a width of 10 mm.
Next, using the obtained packaging bag, a bean sprouts package, a shimeji mushroom package, and a mitake mushroom package of Comparative Example 1 were produced in the same manner as in Example 1. In addition, the inner surface area of the bean sprouts package, the shimeji mushroom package, and the mitake mushroom package of Comparative Example 1 was 7.2 × 10 ⁻² m ² .

The obtained synthetic resin films of Examples 1 to 5 and Comparative Example 1, the packaged bean sprout of Examples 1 to 5 and Comparative Example 1, the packaged shimeji of Examples 1 to 5 and Comparative Example 1, Example 1 Measurements and evaluations described below were performed on the package with maitake of -5 and Comparative Example 1.
Each package used for the following evaluation was stored at 30 ° C. for 3 hours and then stored at 10 ° C. for 4 days. In the following description, a package in a state after being stored under the above-described conditions will be referred to as a package after storage.

-Oxygen permeation amount of synthetic resin film at 23 ° C. and 60% RH: The oxygen permeation amount of the synthetic resin film is an oxygen permeation measuring device (Oxytran (registered trademark) OX-TRAN 1/50) manufactured by MOCON. Was measured by a method based on Appendix B in JIS K7126-2. The measurement conditions were set at 23 ° C. and 60% RH. The unit is cc / m ² · day · atm.

-Elastic modulus at 23 ° C of the synthetic resin film: The elastic modulus of the synthetic resin film was measured by a method based on JIS K7127 under the temperature condition of 23 ° C. The unit is MPa.

-Contact angle of water: About the inner surface of each obtained packaging bag, using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., DROPMASTER-501), 7 seconds after 2 μL of purified water was deposited on the measurement surface The contact angle was measured by the droplet method, and the obtained measured values were evaluated according to the following criteria. The unit is °.
A: 10 ° or more and 30 ° or less.
(Triangle | delta): It is a value higher than 30 degrees, and was 60 degrees or less.
X: A value higher than 60 °.

  About each obtained package after a preservation | save, evaluation shown below was performed. The results are shown in Table 1 below.

Appearance (swelling): The appearance of each package after storage was visually observed, and the appearance was evaluated according to the following criteria.
A: The package was not inflated.
○: Although the package was slightly swollen, it was at a level where there was no practical problem.
X: The package was swollen.

Odor: Sprouts housed in each package after storage, and a panelist skilled in assessing the smell of shimeji or maitake was evaluated according to the following criteria.
A: There was no off-flavor.
○: Slightly off-flavor was generated, but it was at a level with no practical problems.
X: Odor was generated.

-Color of contents: bean sprouts stored in each package after storage, the color of shimeji or maitake was visually observed and evaluated according to the following criteria.
A: Discoloration (browning) did not occur in the contents.
○: Although slight discoloration (browning) occurred in the contents, it was at a level with no practical problem.
X: The content was discolored (brown).

Condensation: Each package after storage was visually observed and evaluated according to the following criteria.
A: Condensation did not occur on the inner surface of the package, or small granular or film-like condensation occurred on the inner surface of the package, but sprouts, shimeji mushrooms or maitake mushrooms contained inside the package Visible from the outside clearly.
○: Mist or particulate condensation occurs on a part of the inner surface of the package, and the bean sprouts are partly housed inside the package, but there are places where it is difficult to visually recognize the shimeji or mitake. In most cases, bean sprouts and shimeji or maitake were clearly visible from the outside (at a level where there was no practical problem).
X: Mist-like dew condensation has occurred on most of the inner surface of the package, and it was difficult to clearly see the shimeji or maitake from the outside from the bean sprouts contained in the package.

  The packaging bodies of Examples 1 to 5 were all capable of maintaining the freshness of the contained contents for a long period of time while maintaining the appearance. On the other hand, the package of Comparative Example 1 did not satisfy the required level in terms of the change in the appearance and the occurrence of a strange odor.

Claims (8)

A freshness-keeping packaging bag for bean sprouts or fungi, which is used to contain bean sprouts or fungi as a content,
The packaging bag is made of a synthetic resin film,
The synthetic resin film has an oxygen transmission amount at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm,
A freshness-keeping packaging bag for bean sprout or fungi whose elastic modulus at 23 ° C. of the synthetic resin film is 150 MPa or more and 1600 MPa or less.   The bean sprouts or the freshness-keeping packaging bag for fungi according to claim 1, wherein the contact angle of water with respect to the inner surface of the packaging bag is 3 ° or more and 60 ° or less.   The bean sprouts or fungi according to claim 1 or 2, wherein the synthetic resin film has a resin layer containing one or more resins selected from the group consisting of polyethylene, polypropylene, polystyrene, and ethylene-vinyl acetate copolymer resin. A freshness-keeping packaging bag.   The bean sprouts or the freshness-keeping packaging bag for fungi according to claim 3, wherein the resin layer further contains an antifogging agent.   The bean sprouts or the freshness holding packaging bag for fungi according to claim 3 or 4, wherein the resin has a melting point of 75 ° C or higher and 170 ° C or lower.   The bean sprouts or fungi freshness-keeping packaging bag according to any one of claims 1 to 5, wherein the synthetic resin film is an unstretched film. In the internal space of the packaging bag made of a synthetic resin film in a deaerated state, bean sprouts or fungi are contained as contents, a bean sprout or fungus-containing package,
The synthetic resin film has an oxygen transmission amount at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm,
A bean sprout or fungus-containing package having an elastic modulus at 23 ° C. of the synthetic resin film of 150 MPa to 1600 MPa. A step of containing sprouts or fungi as contents in the internal space of the packaging bag made of a synthetic resin film;
Obtaining a bean sprouts or fungus-containing package by sealing the packaging bag while degassing,
Including
The synthetic resin film has an oxygen transmission rate at 23 ° C. and 60% RH of 1500 cc / m ² · day · atm to 7000 cc / m ² · day · atm, and the elastic modulus at 23 ° C. of the synthetic resin film is 150 MPa to 1600 MPa. A method for maintaining the freshness of bean sprouts or fungi, which is adjusted to be as follows.