JP6728102B2 - Package of fruits and vegetables - Google Patents

Description

The present invention relates to a package excellent in freshness retention performance of fruits and vegetables containing edible mushrooms, and more specifically, a package containing fruits and vegetables containing edible mushrooms in a packaging container having a polymer film. , A package that can have a specific internal atmosphere after the package is sealed.

In order to maintain the freshness of fruits and vegetables including edible mushrooms such as shiitake mushrooms and shimeji mushrooms for a long time, it has been conventionally practiced to form a desired oxygen concentration atmosphere and store and distribute the fruits and vegetables after harvest. In particular, since edible mushrooms actively maintain their respiratory action even after harvesting, it is important to thoroughly study the mechanism of such respiratory action and prevent quality deterioration during the storage/distribution process. As a method of preventing such quality deterioration and maintaining the freshness of edible mushrooms, various proposals have been made to use a package containing mushrooms which is made of a synthetic resin film having a hole and in which mushrooms are sealed.

For example, Patent Literature 1 is characterized in that the opening area ratio of perforations is 5×10 ^{−5 to} 7×10 ⁻⁴ %, and the surface area in the bag per 100 g of mushrooms is 400 to 1000 cm ^2. A package containing mushrooms made of a synthetic resin film having a hole is disclosed. Furthermore, Patent Document 1 describes that the average pore diameter of the holes is preferably 20 μ to 150 μ, and the number of the holes is preferably plural per package (paragraph [0005]).
Further, in Patent Document 2, in a mushroom package of shimeji mushrooms in which shimeji mushrooms such as beech shimeji are enclosed in a bag made of a synthetic resin film, a plurality of fine holes are formed in the bag at intervals to separate the inside and outside of the bag. It is described that it is preferable to form 1 to 3 micropores having a diameter of 100 μm so that a small amount of air permeability is provided and the area ratio to the bag surface area is 4.60×10 ⁻⁵ % or less (paragraph [ [0008][0009]).

JP-A-5-153907 JP, 2000-228946, A

However, according to a study by the present inventors, in a mushroom-containing package made of such a perforated synthetic resin film, when stored at 23° C. after sealing the package, generation of odor due to ammonia It has been found that this may cause quality deterioration. In addition, it has been found that such quality deterioration can occur even when cold storage is started at 5°C after the packaging is sealed, and therefore it is eaten as fresh food and its distribution is live. From the viewpoint of food safety, it has become an urgent task to solve the problem of such quality deterioration in the handling of edible mushrooms which is carried out under the condition. In view of the limitations of the conventional technique, the present invention is a package in which fruits and vegetables containing edible mushrooms are stored in a packaging container, which is characteristic of the edible mushrooms in the package and suppresses deterioration over time. It is an object of the present invention to provide a package which is excellent in the function of retaining the freshness of the fruits and vegetables.

The present inventors have conducted a number of trials and errors from various viewpoints, and as a result of extensive investigations, the above-mentioned quality deterioration, which could not be suppressed by the conventional technology, is caused by vegetables and fruits containing edible mushrooms in a packaging container containing a polymer film. The present invention has been completed, and it was found that the problem can be solved by using a packaging body containing the above, which can have a specific internal atmosphere after the packaging body is sealed.
That is, the gist of the present invention is as follows.
[1]
A package in which fruits and vegetables containing edible mushrooms are stored in a packaging container containing a polymer film,
When stored refrigerated at 5℃,
The internal carbon dioxide concentration is 3% or more and 10% or less in at least a part of the period from 2 days after the packaging is sealed to 15 days after the packaging is sealed, and the packaging is performed from 2 days after the packaging is sealed. A package having an internal oxygen concentration of 10% or more and 25% or less in at least a part of the period up to 15 days after the body is sealed.
[2]
A package in which fruits and vegetables containing edible mushrooms are stored in a packaging container containing a polymer film,
When stored refrigerated at 5℃,
The internal carbon dioxide concentration is 3% or more and 10% or less for 2 days after the package is sealed and 15 days after the package is sealed, and 2 days after the package is sealed and 15 after the package is sealed. The package according to [1], wherein the daily internal oxygen concentration is 10% or more and 25% or less.
[3]
The package according to [1] or [2], which can suppress the generation of the odor of the edible mushrooms for 9 days or more after the packaging is sealed.
[4]
When refrigerated at 5℃,
From 2 days after the package is sealed to 15 days after the package is sealed, the change rate of the internal carbon dioxide concentration is within 4% and the change rate of the internal oxygen concentration is within 4%, [1] The package according to any one of [3] to [3].
[5]
The package according to any one of [1] to [4], wherein nitrogen is enclosed in the packaging container.
[6]
The oxygen permeability of the polymer film at 20° C. and 90% RH is 30000 cc/m ² ·day·atm or more and 70000 cc/m ² ·day·atm or less, and the packaging container has an opening area of 0.007. The package according to any one of [1] to [5], which has at least one or more micro holes of 0.11 mm ² .
[7]
The package according to any one of [1] to [6], wherein the polymer film has a thickness of 15 to 45 μm.
[8]
The package according to any one of [1] to [7], wherein the polymer film is a stretched polypropylene film, a polyethylene film, or a laminate of a stretched film and a polyethylene film.
[9]
The polymer film contains an antifogging agent and at least one antibacterial agent, or is coated with at least one antibacterial agent, according to any one of [1] to [8]. The package described.
[10]
The package for keeping freshness of fruits and vegetables according to any one of [1] to [9], which further contains a moisture absorbent and/or an antibacterial agent.
[11]
The package for keeping freshness of fruits and vegetables according to any one of [1] to [10], wherein the edible mushroom is shiitake or shimeji mushroom.

In a preferred embodiment of the present invention, a package comprising a polymer film-containing packaging container containing fruits and vegetables containing edible mushrooms, which seals the package when refrigerated at 5°C. The internal carbon dioxide concentration is 1% or more and 18% or less, preferably 1% or more and 15% or less, and more preferably at least a part of the period from 2 days to 15 days after the packaging is sealed. It is 1% or more and 10% or less, more preferably 3.0% or more and 10% or less, even more preferably 3.2% or more and 9% or less, still more preferably 3.5% or more and 8% or less. Is. In a preferred embodiment of the present invention, the internal oxygen concentration is 3% or more and 30% or less in at least a part of the period from 2 days after the package is sealed to 15 days after the package is sealed. It is preferably 5% or more and 30% or less, more preferably 5% or more and 25% or less, even more preferably 10% or more and 25% or less, and still more preferably 12% or more and 20% or less, Even more preferably, it is 13.5% or more and 18.5% or less, and most preferably 14.0% or more and 18.0% or less.

In a preferred embodiment of the present invention, a package comprising a container containing a polymer film and containing fruits and vegetables containing edible mushrooms, the package being sealed when refrigerated at 5°C. 2 days after and 15 days after sealing the package, the internal carbon dioxide concentrations are both 1% or more and 18% or less, preferably 1% or more and 15% or less, and more preferably 1% or more. % Or more and 10% or less, still more preferably 3.0% or more and 10% or less, still more preferably 3.2% or more and 9% or less, and most preferably 3.5% or more and 8% or less. is there. Most preferably, these internal carbon dioxide concentrations are in the above range from 2 days after the sealing of the package to 15 days after the sealing of the package.

In a preferred embodiment of the present invention, a package comprising a polymer film-containing packaging container containing fruits and vegetables containing edible mushrooms, which seals the package when refrigerated at 5°C. 2 days later and 15 days after sealing the package, the internal oxygen concentration was 3% or more and 30% or less, preferably 3% or more and 30% or less, and more preferably 5%. 25% or more, more preferably 10% or more and 25% or less, still more preferably 12% or more and 20% or less, still more preferably 13.5% or more and 18.5 or less, Most preferably, it is 14.0% or more and 18.0% or less. Most preferably, these internal oxygen concentrations are in the above range from 2 days after the sealing of the package to 15 days after the sealing of the package.

In a preferred embodiment of the present invention, the generation of the odor of the edible mushroom can be suppressed after sealing the package, preferably for 9 days or more, more preferably for 13 days or more, still more preferably for 15 days or more. ..

In a preferred embodiment of the present invention, the oxygen permeability of the polymer film at 20° C. and 90% RH has a lower limit value of preferably 30,000 cc/m ² ·day·atm, more preferably 40,000 cc/m ² ·. day·atm, more preferably 45,000 cc/m ² ·day·atm, and the upper limit value is preferably 70,000 cc/m ² ·day·atm, more preferably 60000 cc/m ² ·day·atm, further preferably 55,000 cc/ m ² ·day·atm.

Further, in a preferred embodiment of the present invention, the opening area of the packaging container preferably has at least one fine hole having an opening area of 0.007 to 0.11 mm ² , and more preferably an opening area of 0.01 to. It has 3 to 15 fine holes of 0.08 mm ² , and more preferably has 6 to 12 fine holes having an opening area of 0.02 to 0.06 mm ² .

The technical effect brought about by each of the preferred embodiments of the present invention as described above is demonstrated by comparison of the experimental results of Examples and Comparative Examples described later.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to suppress the quality deterioration which is characteristic of the edible mushrooms, such as a shiitake mushroom, and shimeji mushroom, and time, ie, odor generation, for a comparatively long period after sealing a package.

Hereinafter, modes for carrying out the present invention will be described.
The present invention relates to a packaging body in which fruits and vegetables containing edible mushrooms are stored in a packaging container containing a polymer film, and (i) after the packaging body is sealed when stored refrigerated at 5°C. The internal carbon dioxide concentration is 15% or more and 25% or less both on the day and 15 days after the package is sealed, and the internal oxygen concentration is 2 days after the package is sealed and 15 days after the package is sealed. Is also 4% or less, and (ii) when stored at 23° C., the internal carbon dioxide concentration decreases in at least a part of the period from 1 day after sealing the package to 8 days after sealing the package. , The package. That is, the package of the present invention has at least a packaging container and fruits and vegetables stored therein.

Packaging Container The packaging container that constitutes the package of the present invention comprises a polymer film. Here, "comprising a polymer film" refers to a case where the entire packaging container is made of a polymer film, and a case where a part of the packaging container such as the lid material is made of a polymer film. The purpose is to include both.
Therefore, the packaging container may be a flexible packaging container, a so-called packaging bag, which is wholly or principally composed of a flexible polymer film, such as a flexible polymer film and coated paper. It may be a flexible packaging container in which other flexible members other than the above are combined, or a packaging container in which a flexible polymer film and a rigid member are combined, for example, as a lid material. The molecular film may be combined with a rigid member such as a tray or a cup.

In an embodiment in which the packaging container is a so-called packaging bag, for example, two polymer films are superposed on each other, or one polymer film is folded, and three or two sides are heat-sealed. It is possible to form a packaging bag by fusing, for example. The remaining one side can be sealed by arranging the contents such as fruits and vegetables in the packaging bag and then similarly heat-sealing the contents.
The shape of such a packaging bag in a plan view may be a circle, a triangle, a quadrangle, or a polygon of a quadrangle or more, but it is preferably a rectangle from the viewpoint of workability and ease of handling.

The packaging container used in the present invention comprises the above-described polymer film, and the oxygen permeability thereof is preferably within the above range, and the amount and type of fruits and vegetables to be stored can be preferably used. The most suitable oxygen permeability can be selected according to various gas concentrations such as the desired internal oxygen concentration.

Fruits and vegetables The package of the present invention contains fruits and vegetables containing edible mushrooms in the packaging container. Here, the phrase "the fruit and vegetables include edible mushrooms" means that both of the case where all of the fruit and vegetables are composed of edible mushrooms and the case where part of the fruit and vegetables are composed of edible mushrooms. is there. Therefore, the fruits and vegetables stored in the packaging container may or may not include vegetables, fruits and the like other than edible mushrooms. Furthermore, as long as it contains edible mushrooms, it may contain components other than fruits and vegetables, for example, foods other than fruits and vegetables, seasonings, food additives and the like.

The "mushroom" in the edible mushrooms (stored in the packaging container) that constitutes the package of the present invention is a concept that includes a relatively large fruiting body among fungi, or a child itself. It is not limited to fruits and vegetables distributed under the name "mushroom" itself.
That is, the edible mushrooms referred to herein are not limited to these, but include, as preferred examples, all of shiitake mushrooms, shimeji mushrooms, enokitake mushrooms, eryngii mushrooms, matsutake mushrooms, and the like. Particularly preferred examples include shiitake mushrooms and shimeji mushrooms.

The edible mushroom may be cut into a desired shape and size, and the shape and size are not particularly limited.
The edible mushrooms may be sterilized or washed to maintain their freshness and taste.

In the present invention, there is no particular limitation on fruits and vegetables other than edible mushrooms that can be stored together with edible mushrooms in the packaging container, and unheated or heated fruits and vegetables that can be edible with edible mushrooms can be stored as appropriate. .. Specific examples of such fruits and vegetables include fruits such as banana, mango, plum, apple, strawberry, mandarin orange, grape, Japanese pear, pear, Japanese radish, carrot, potato, root vegetables such as burdock, tomato, Fruit vegetables such as cucumber, eggplant, peppers, edamame, okra, mung bean sprouts, soybean bean sprouts, buds such as tokyo, mushrooms (mushrooms) such as shiitake, shimeji, eringi, maitake, matsutake, and broccoli. , Spinach, komatsuna, bok choy, non-shredded cabbage, lettuce, leafy vegetables such as asparagus, flowers or seedlings, but are not limited thereto. From the effect of the present embodiment of controlling and maintaining the oxygen concentration, it is particularly effective for maintaining the freshness of fruits and vegetables that are substantially breathing.

In the present invention, the form of fruits and vegetables containing edible mushrooms stored in a packaging container and kept fresh is not particularly limited. The fruits and vegetables may have been subjected to any or all of the treatments such as washing, cooling and dehydration, or may be those without any of these treatments.

Since edible mushrooms have a high nutritional value and may have medicinal components, they can be consumed not only as foods but also as medicines, and thus have a particularly high economic value. The present embodiment can be effectively used to maintain the freshness of such edible mushrooms, and thus has a particularly high economic value.

Depending on the type and form of edible mushrooms (and fruits and vegetables that are stored with the edible mushrooms, if present), the most preferable oxygen concentration for maintaining freshness will vary to some extent. The aspect of the polymer film to be given is also different, but by appropriately setting these, the freshness of the edible mushrooms (and fruits and vegetables stored together with the edible mushrooms, if any) is more effectively improved by this aspect. Hold can be done.

Package The preferable carbon dioxide concentration and oxygen concentration of the package of the present invention, and their daily changes are as described above. By using such a package, it is possible to extremely effectively suppress the quality deterioration of the edible mushrooms in the fruits and vegetables contained in the packaging container.

The oxygen concentration inside the package is specified by, for example, sampling the gas inside the package with a sampling needle tube and measuring the oxygen concentration with a zirconia oxygen concentration meter for food packaging or gas chromatography. You can
Here, "after packaging" means the elapsed time after the packaging container is sealed after storing fruits and vegetables containing edible mushrooms in the packaging container, and "8 days after packaging" is in the packaging container. The state after 8 days (192 hours) have passed since the packaging container was sealed after storing fruits and vegetables containing edible mushrooms.

Polymer Film As described above, in order to realize the excellent features of the present invention, it is desirable to configure the packaging container using a polymer film having a predetermined oxygen permeability.

The oxygen permeability of the polymer film used in the present invention can be measured, for example, by the following method.
First, a bag having an inner size of a (cm) x b (cm) is formed by the following method.
Fold one film into two almost evenly and set the scale of heating conditions to 3 with an impulse sealer (manufactured by Fuji Impulse Co., product number Fi-200-10WK) with a width of about 5 mm, and heat seal the film. Heat-seal one side approximately perpendicular to the heat-sealed side so that the side is almost in the center, and heat-seal the entire other side except for the end of about 2 cm which is the communicating part of the other side, and the inside dimension is 220 mm × Form a 240 mm bag.
Next, nitrogen gas is injected from the communication section, and when the inside of the bag becomes saturated, almost all the gas in the bag is discharged from the communication section. After repeating this operation 5 times, nitrogen gas is injected to saturate the inside of the bag with nitrogen gas, and the communication part is heat-sealed under the same conditions with the impulse sealer. The bag saturated with nitrogen gas is left for 6 hours in a room at 22° C. and 40% relative humidity in air (1 atm, oxygen concentration: 21%, nitrogen concentration: 79%).
Next, about 20 cc is sampled with a sampling needle tube, and the oxygen concentration in the bag is measured with a zirconia oxygen concentration meter for food packaging (Model No. LC-750F, manufactured by Toray Engineering Co., Ltd.). Further, the volume of gas in the bag is measured, and the oxygen permeability is calculated from the following formula.
(Formula) oxygen permeability = internal oxygen concentration change (%) / 100 × volume ^{(cm 3) × 24 × 60} / time (360 minutes) × 10000 cm ² / area ^{(2 × a × b cm 2} ) / oxygen min Pressure (0.21 atm)

The oxygen permeability of the polymer film can be appropriately adjusted by appropriately selecting the material, thickness, processing method, and the like of the polymer film. For example, in the case of a biaxially oriented polypropylene (OPP) film, by setting the thickness to 60 μm or less, preferably 55 μm or less, more preferably 50 μm or less, still more preferably 45 μm or less, most preferably 40 μm or less, 20° C., The oxygen permeability at 90% RH can be 500 cc/m ² ·day·atm or more. Considering mechanical strength and workability together, the thickness of the polymer film is preferably from 10 to 60 μm, more preferably from 15 to 55 μm, even more preferably from 20 to 50 μm, The thickness is more preferably 20 to 45 μm, and particularly preferably 15 to 45 μm.

As described above, the oxygen permeability of the polymer film can be adjusted by appropriately selecting the material, thickness, processing method, etc. of the polymer film, so that it is not always necessary to adjust the oxygen permeability. It is not necessary to provide an opening in the polymer film.
If the polymer film is not provided with openings, the manufacturing process becomes simpler and less expensive, and it is not necessary to precisely control the size, shape, etc. of the openings.
The absence of an opening in the polymer film can be confirmed by, for example, the polymer film forming the packaging container having no through hole which can be confirmed by an ink leakage checker.

On the other hand, in one embodiment of the present invention, a thick polymer film, or when it is necessary to use a polymer material having a low oxygen permeability, the desired oxygen permeability for maintaining the respiration of fruits and vegetables. To achieve this, an opening provided in the polymer film may be used together. The shape of the opening is not particularly limited, and may be circular, substantially circular, or slit-shaped. A circular or substantially circular opening is preferable because it is easy to process, and a slit-shaped opening is preferable because it can effectively prevent foreign matter from entering.
The size of each opening and the number of openings can be appropriately set and changed as long as the oxygen permeability of the polymer film is appropriate, and in that case, the openings occupying the effective area of the polymer film. The number of is a guide. For example, in the case of a slit-shaped opening having a length of 2 mm, the width as a through-hole cannot be visually recognized by observation with an optical microscope (manufactured by Olympus, model SZH-131) at a magnification of 4 times in a closed state. When one is provided, it has an effect of increasing the oxygen permeability of about 1000 cc/m ² ·day·atm for each 200 mm×200 mm packaging container, and the packaging required based on such knowledge. It is preferable to determine the number of slit openings from the oxygen permeability of the entire container.

The thickness of the polymer film used in the present invention is not particularly limited, and suitable oxygen permeability, flexibility when forming a packaging container, strength, transparency, economical efficiency, etc. From the viewpoint of accuracy and easiness in forming the portion, etc., a suitable thickness may be appropriately selected in relation to the material forming the polymer film. Typically, the thickness of the polymer film when the opening is provided is preferably 10 to 60 μm, more preferably 15 to 55 μm, further preferably 20 to 50 μm, and further preferably 20 to 45 μm. Is more preferable, and 15 to 45 μm is particularly preferable.

The material of the polymer film is not particularly limited, but a polymer used in a conventional film for packaging fruits and vegetables can be appropriately used. Examples thereof include polyethylene, polypropylene, polyethylene terephthalate, polystyrene, nylon (polyamide), ethylene vinyl acetate copolymer (EVA), polybutylene succinate, polybutylene succinate adipate, and polylactic acid. Further, for example, a natural polymer such as cellophane can be used. Further, any one of these materials may be used alone, or a plurality of these materials may be blended and/or laminated.

From the viewpoint of ease of processing and cost, the material of the polymer film is preferably a thermoplastic resin. Examples of the thermoplastic resin include homopolymers or copolymers of α-olefins such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene. Specifically, high-pressure low density polyethylene, linear low density polyethylene (LLDPE), high density polyethylene and other ethylene polymers, propylene homopolymers, propylene/α-olefin random copolymers, propylene block copolymers. And propylene polymers such as poly-1-butene, and polyolefins such as poly-4-methyl/1-pentene. Examples of the thermoplastic resin include polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, polyamides such as nylon-6, nylon-66 and polymeta-xylene adipamide, polyvinyl chloride, polyimide, ethylene acetic acid. Examples thereof include vinyl copolymers or saponified products thereof, polyvinyl alcohol, polyacrylonitrile, polycarbonate, polystyrene, ionomers, polylactic acid, polybutylene succinate, and other biodegradable resins, or a mixture thereof. These thermoplastic resins may be used alone or in combination of two or more. Among these, as the thermoplastic resin, polyolefin, polyester, polyamide and the like are preferable because they have excellent rigidity and transparency. Further, as the thermoplastic resin, ethylene-based polymers and propylene-based polymers are more preferable because they are lightweight and have excellent film processability, and propylene-based polymers are more preferable from the viewpoint of flexibility and transparency.

<Propylene polymer>
As the propylene-based polymer, propylene homopolymer (also called homo PP), which is manufactured and sold under the name of polypropylene, propylene/α-olefin random copolymer (also called random PP). , A crystalline polymer containing propylene as a main component, such as a mixture of a propylene homopolymer and a low crystalline or amorphous propylene/ethylene random copolymer (also referred to as block PP). .. The propylene-based polymer may be a mixture of propylene homopolymers having different molecular weights, and includes a propylene homopolymer and a random copolymer of propylene and ethylene or an α-olefin having 4 to 10 carbon atoms. It may be a mixture.

Specific examples of the propylene-based polymer include polypropylene, propylene/ethylene copolymer, propylene/ethylene/1-butene copolymer, propylene/1-butene copolymer, propylene/1-pentene copolymer. , A propylene/1-hexene copolymer, a propylene/1-octene copolymer, etc. as a main monomer, and a copolymerization of this with at least one or more selected from ethylene and α-olefins having 4 to 10 carbon atoms. An example is coalescence. These may be used alone or in combination of two or more.

The density of the propylene-based polymer is preferably 0.890 to 0.930 g/cm ³ , and more preferably 0.900 to 0.920 g/cm ³ . The MFR (ASTM D1238 load 2160 g, temperature 230° C.) of the propylene-based polymer is preferably 0.5 to 60 g/10 minutes, more preferably 0.5 to 10 g/10 minutes, and even more preferably 1 to 5 g/10 minutes. Is more preferable.

<Ethylene polymer>
As the ethylene-based polymer, a homopolymer of ethylene, a copolymer containing ethylene as a main monomer and at least one α-olefin having 3 to 8 carbon atoms, an ethylene-vinyl acetate copolymer, Saponified products and ionomers are mentioned. Specifically, polyethylene, ethylene/propylene copolymer, ethylene/1-butene copolymer, ethylene/1-pentene copolymer, ethylene/1-hexene copolymer, ethylene-4-methyl-1-pentene Examples of the copolymer include a copolymer and ethylene/1-octene copolymer as a main monomer, and a copolymer of ethylene and at least one or more α-olefin having 3 to 8 carbon atoms. The proportion of α-olefin in these copolymers is preferably 1 to 15 mol %.

Examples of the ethylene polymer include ethylene polymers manufactured and sold under the name of polyethylene. Specifically, high-pressure low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE) are preferable, and LLDPE is more preferable. LLDPE is a copolymer of ethylene and a small amount of propylene, butene-1, heptene-1, hexene-1, octene-1, 4-methyl-pentene-1 and the like. The ethylene-based polymer may be a homopolymer of ethylene or a polymer mainly composed of ethylene such as LLDPE.

Density of the ethylene polymer is preferably ^{0.910~0.940g / cm 3, 0.920~0.930g / cm} 3 is more preferable. When the density is 0.910 g/cm ³ or more, heat sealability is improved. Further, when the density is 0.940 g/cm ³ or less, workability and transparency are improved.

The blend and/or the laminate may be a blend and/or a laminate of any of the above-mentioned polymers, and any of the above-mentioned polymers and a material other than the polymer may be used. May be a blend and/or a laminate. That is, a polymer film is a material other than a polymer, for example, a heat stabilizer (antioxidant), a weather stabilizer, an ultraviolet absorber, a lubricant, a slip agent, a nucleating agent, an antiblocking agent, an antistatic agent, an antifogging agent. In addition to pigments, dyes, etc., it may contain various fillers such as talc, silica, diatomaceous earth, etc., or may be a laminate of a polymer film and metal foil, paper, nonwoven fabric, etc.

The polymer film forming the packaging container in the present invention may be either a non-stretched film or a stretched film.
From the viewpoint of mechanical strength and the like, stretched films of various polymers can be preferably used.
In particular, a stretched film using a propylene-based polymer (stretched polypropylene film) is excellent in mechanical strength, transparency, heat resistance and the like, and thus can be particularly preferably used in the packaging container used in the present invention.
Further, the film using an ethylene polymer (polyethylene film) may be either a non-stretched film or a stretched film, but from the viewpoint of heat sealability and the like, a non-stretched film is particularly preferably used. be able to.
Examples of particularly preferable polymer films constituting the packaging container in the present invention include a stretched polypropylene film, a polyethylene film, and a laminate of a stretched film and a polyethylene film.

<Stretched polypropylene film>
The stretched polypropylene film preferably used in the present invention may be composed of a film stretched in at least one direction, or the stretched polypropylene film itself may be stretched in at least one direction. When a biaxially stretched film is obtained as a stretched polypropylene film, it can be easily produced by, for example, sequential or simultaneous biaxial stretching. When a biaxially stretched film is obtained as a stretched polypropylene film, it is usually stretched 5 to 8 times in the machine direction and then 8 to 10 times in the transverse direction by using a tenter mechanism to obtain the final film thickness. 20 to 40 μm, or by stretching 5 to 10 times (25 to 100 times in area magnification) in the machine direction and the transverse direction, respectively.
<Polyethylene film>
The polyethylene film preferably used in the present invention is a film containing the ethylene polymer. Although various known molding methods can be used for the polyethylene-based film, cast molding by extrusion with an extruder is preferable from the viewpoint of production efficiency.

<Stretched film>
Polyamide film made of nylon 6, nylon 66, etc., film made of polyester typified by polyethylene terephthalate, polyethylene naphthalate, polycarbonate film, ethylene/vinyl alcohol copolymer film, polyvinyl alcohol film, polyvinyl chloride film, polyvinylidene chloride A uniaxially or biaxially stretched film comprising a film, a polystyrene film, a polyolefin such as polypropylene, and poly L lactic acid, poly D lactic acid, or a stereocomplex polylactic acid in which poly L lactic acid and poly D lactic acid are precisely coordinated.

<Laminate of stretched film and polyethylene film>
The laminate of the stretched film and the polyethylene film preferably used in the present invention is obtained by laminating the layer of the polyethylene film and the layer of the stretched film. The polyethylene film may be stretched in one direction or in two directions, but it is preferably an unstretched film from the viewpoint of stability of mechanical strength of the packaging bag.
From the viewpoint of adhesion stability, it is necessary to perform a corona treatment on the surface of the stretched film on which the adhesive is applied. preferable. Specifically, the surface tension of the film surface after the corona treatment is preferably 35 mN/m or more, and more preferably 40 mN/m or more, from the viewpoint of adhesion stability.

In addition, these polymer films may be subjected to stretching processing, anti-fog processing or printing, and inorganic antibacterial agents such as silver and copper, and organic antibacterial agents such as chitin, chitosan and allyl isothiocyanate. The agent may be applied, or these may be kneaded into the film.
From the viewpoint of maintaining the freshness of contents such as fruits and vegetables, the polymer film preferably contains at least one antibacterial agent.
In addition, a specific amount of a specific surfactant is present on the surface of the polymer film, or the specific amount of the specific surfactant is included in the polymer film, so that the polymer film may have an antibacterial function. For example, at least one compound selected from the group consisting of palmityldiethanolamine, stearyldiethanolamine, glycerin monolaurate and diglycerin monolaurate is preferably present on at least one surface of the polymer film, It is particularly preferred that one compound is present in an amount of 0.002-0.5 g/m ² . Alternatively, the polymer film preferably contains at least one compound selected from the group consisting of palmityldiethanolamine, stearyldiethanolamine, glycerin monolaurate and glycerin monocaprate, and 0.001 to 3 parts by mass. It is particularly preferable to contain.
There is a specific amount of a specific surfactant on the surface of the polymer film, or the polymer film contains a specific amount of a specific surfactant, dew condensation on the surface of the polymer film is suppressed, various bacteria By suppressing the reproduction of the bacteria, the growth of various bacteria in the dew condensation is suppressed and the antibacterial function is exerted.

From the viewpoint of transparency, flexibility, cost, etc., it is particularly preferable to use a stretched polypropylene film, which has been widely used in the related art, or a laminate of a stretched polypropylene film and a polyethylene-based film as a polymer film. .. Since these films are generally excellent in heat sealability, they have good productivity in the production of packaging containers.
In this case, when the stretched propylene film is used alone, the thickness thereof is preferably 10 to 100 μm, and when the laminate of the stretched polypropylene film and the polyethylene-based film is used, the former thickness is 10 to 50 μm. The latter preferably has a thickness of 10 to 120 μm.

When a polymer film that is not necessarily suitable for heat sealing is used, it may be formed by laminating or coating a sealant layer on all or part of the polymer film. For example, a cellophane film coated with an acrylic resin, a film obtained by laminating polyethylene terephthalate (PET) with linear low-density polyethylene (LLDPE) polystyrene and EVA can be used, and these can be used as suitable polymer films.

Method for Producing Package and Method for Retaining Freshness Hereinafter, a method for producing a package of the present invention will be described by taking a package for retaining freshness of edible mushrooms as an example.

The edible mushrooms are packed in a packaging container (one side of which is not sealed) containing the polymer film used in the present embodiment, the packaging container is sealed after weighing, and the packaging for keeping the freshness of the edible mushrooms is obtained. Manufactured.

The package for freshness preservation of fruits and vegetables of the present embodiment may be filled with nitrogen and/or deaerated when storing fruits and vegetables containing edible mushrooms and sealing the packaging container. It may be possible to suppress the odor by performing nitrogen filling and/or deaeration.
In addition, degassing may be performed after sealing the packaging container from the viewpoints of improving efficiency in the distribution process, saving space, and eliminating a specific gas.

In the package of the present invention, only fruits and vegetables containing edible mushrooms may be stored in the packaging container, or other members may be stored.
For example, in addition to fruits and vegetables, a hygroscopic agent and/or an antibacterial agent may be contained in the packaging container.
The hygroscopic agent is not particularly limited, and known or commercially available materials having a hygroscopic effect or a humidity adjusting effect can be used. Suitable examples of the hygroscopic agent include activated carbon, silica gel, alumina gel, silica alumina gel, anhydrous magnesium sulfate, zeolite, synthetic zeolite, calcium oxide, calcium chloride, and burnt alum, or a mixture thereof. Examples include, but are not limited to:
Among these, it is particularly preferable to use activated carbon, which has relatively little concern about effects on fruits and vegetables and use near fruits and vegetables as foods. The activated carbon may be powdery or granular, and the raw material may be coconut shell, sawdust, charcoal, bamboo charcoal, lignite, peat, rice, petroleum pitch, or any other material. It is desirable that the activated carbon be packed in a unit such as a non-woven fabric, cellophane, paper or the like, but the activated carbon itself may be in a fibrous form. As the wrapping material for the activated carbon, it is preferable to use one having a heat-sealing property, such as a nonwoven fabric made of a synthetic resin, but as long as it has water vapor permeability and the activated carbon does not spill, it may be paper, natural fiber, or the like. no problem.

There is no particular limitation on the antibacterial agent, and substances having an antibacterial effect can be appropriately used, but there is relatively little concern about the effects on fruits and vegetables including edible mushrooms and the use of them near foods such as fruits and vegetables. An antibacterial agent can be preferably used. More specifically, natural antibacterial agents such as chitosan, allyl isothiocyanate, hinokitiol, limonene can be stored in the packaging container.

Hereinafter, the present invention will be specifically described with reference to Examples/Comparative Examples. The present invention is not limited to the following examples in any sense.

In the following examples/comparative examples, evaluation of each characteristic was performed by the following methods.
(Oxygen permeability)
First, a bag having an inner size of 210 mm×175 mm was formed by the following method.
Fold one film into two almost evenly, and heat-seal it with a width of about 5 mm and set the scale of heating conditions to 3 with an impulse sealer (Fuji Impulse, product number Fi-200-10WK). Heat seal the entire one side that is almost perpendicular to the heat-sealed side so that the side is almost in the center, and the entire side except the end of about 2 cm that is the communicating part of the other side, and the inside dimension is 210 mm × A 175 mm bag was formed. At that time, one pinch cock for gas measurement was provided in the heat seal part.
Next, nitrogen gas was injected from the communication part, and after the bag was saturated, almost all the gas in the bag was discharged from the communication part. After repeating this operation 5 times, nitrogen gas was injected to saturate the inside of the bag with nitrogen gas, and the communication part was heat-sealed under the same conditions with the impulse sealer. The bag saturated with nitrogen gas was left to stand in a room at 22° C. and 40% relative humidity in air (1 atm, oxygen concentration: 21%, nitrogen concentration: 79%) for 6 hours.
Next, about 20 cc of gas in the bag was sampled from a pinch cock for gas measurement, and the oxygen concentration in the bag was measured with a zirconia oxygen concentration meter for food packaging (Toray Engineering Co., model LC-750F). Further, the volume of gas in the bag was measured, and the oxygen permeability was calculated from the following formula.
(Equation) Oxygen permeability=internal oxygen concentration change (%)/100×volume (cm ³ )×24×60/hour (360 minutes)×10000 cm ² /area (1232 cm ² )/oxygen partial pressure (0.21 atm )
(Oxygen concentration)
About 20 cc of gas in the package was sampled from a pinch cock for gas measurement, and the oxygen concentration in the bag was measured by a zirconia oxygen concentration meter for food packaging (Toray Engineering Co., model LC-750F).
(Odor)
The inside of the bag was measured using a handy odor monitor (OMX-ADM) (manufactured by Shinei Technology Co., Ltd.), and the odor was digitized in NH ₃ conversion.

表１から、５℃で冷蔵保管した場合に、包装体の封止後２日と包装体の封止後１５日の内部二酸化炭素濃度がいずれも４．７％〜６．０％であって、３％以上１０％以下の範囲内であり、また、包装体の封止後２日と包装体の封止後１５日の内部酸素濃度がいずれも１５％以上であって、１０％以上２５％以下の範囲内であることが読み取れる。
そして、このように、５℃で冷蔵保管した場合、表２から、後述の比較例１及び２に比べて、臭気の発生、具体的には、アルコール発酵に伴うと推測されるアンモニア臭の発生がほとんど認められず、アンモニア臭の発生が抑制されている点で、包装体の封止直後から経時的な品質劣化が著しく抑制され、椎茸の鮮度維持に有利であることが読み取れる。 (Example 1)
A 140 mm x 180 mm size bag was heat-sealed using a 25 μm thick anti-fog biaxially oriented polypropylene film with 6 circular openings with a diameter of 70 μm provided on the front surface and 3 on the back surface by laser processing. did. A pinch cock was attached to the bag.
When the oxygen permeability of this bag was measured, it was 50,000 cc/m ² ·day·atm.
100 g of shiitake mushroom, which is an edible mushroom prepared in advance, was packaged in a bag, and the upper part was sealed with heat seal to prepare a packaged body containing the shiitake mushroom.
This package is stored in a refrigerator set at 5°C, the oxygen concentration and carbon dioxide concentration inside the bag are measured over time, the inside of the bag is measured using a handy odor monitor, and the odor is calculated as NH _3. Digitized.
Tables 1 and 2 show the results when stored refrigerated at 5°C.

From Table 1, when stored refrigerated at 5° C., the internal carbon dioxide concentration 2 days after sealing the package and 15 days after sealing the package were both 4.7% to 6.0%. It is within the range of 3% or more and 10% or less, and the internal oxygen concentration is 15% or more for both 2 days after the sealing of the package and 15 days after the sealing of the package. It can be read that it is within the range of% or less.
When the sample was stored refrigerated at 5° C. as described above, from Table 2, compared with Comparative Examples 1 and 2 described later, the generation of odor, specifically, the generation of ammonia odor presumed to accompany alcohol fermentation was observed. From the fact that the occurrence of ammonia odor is suppressed, the deterioration of quality with time is remarkably suppressed immediately after the packaging body is sealed, and it can be read that it is advantageous for maintaining the freshness of shiitake mushrooms.

(Comparative Example 1)
In the same manner as in Example 1 except that a biaxially stretched polypropylene film having a thickness of 25 μm was used, a packaged body containing 100 g of shiitake mushroom was prepared, and measured and evaluated. A pinch cock was attached to the bag.
The oxygen permeability of the bag was 1790 cc/m ² ·day·atm.
Similar to Example 1, Tables 1 and 2 show the results when stored refrigerated at 5°C.
From Table 1, when stored refrigerated at 5° C., the internal carbon dioxide concentration 2 days after sealing the package and 15 days after sealing the package were both about 15% or more and 25% or less. % Is outside the range of 10% or less, and the internal oxygen concentration is 4% or less for 2 days after the packaging is sealed and 15 days after the packaging is sealed, and is 10% or more and 25% or less. It can be read that it is outside the range.
In this way, when stored refrigerated at 5° C., from Table 2, the measured value of odor generation, specifically, the ammonia odor presumed to accompany alcohol fermentation is higher than that in Example 1 described above. It can be read that the quality of the package rapidly rises immediately after the packaging is sealed, and the extremely remarkable deterioration of quality with time progresses.

(Comparative example 2)
A 25 µm-thick anti-fog biaxially oriented polypropylene (anti-fog OPP) film was used, and in the same manner as in Example 1, a package containing 100 g of shiitake was prepared, and measurement and evaluation were performed. It was A pinch cock was attached to the bag.
The oxygen permeability of the bag was 1000 cc/m ² ·day·atm.
Similar to Example 1, Tables 1 and 2 show the results when stored refrigerated at 5°C.
From Table 1, when stored refrigerated at 5° C., the internal carbon dioxide concentration 2 days after sealing the package and 15 days after sealing the package were both about 15% or more and 25% or less. % Is outside the range of 10% or less, and the internal oxygen concentration is 4% or less for 2 days after the packaging is sealed and 15 days after the packaging is sealed, and is 10% or more and 25% or less. It can be read that it is outside the range.
In this way, when stored refrigerated at 5° C., from Table 2, the measured value of odor generation, specifically, the ammonia odor presumed to accompany alcohol fermentation is higher than that in Example 1 described above. It can be read that the quality of the package rapidly rises immediately after the packaging is sealed, and the extremely remarkable deterioration of quality with time progresses.

The package of the present invention is a package in which fruits and vegetables containing edible mushrooms such as shiitake mushrooms and shimeji mushrooms are stored in a packaging container, and the edible mushrooms such as shiitake mushrooms and shimeji mushrooms have characteristic deterioration over time. In other words, it realizes technical effects with high practical value, such as suppressing the generation of odors for a relatively long period of time after the packaging is sealed, and is used in industries such as food processing, distribution, and eating out. It has high availability in each field.

Claims (11)

A package in which fruits and vegetables containing edible mushrooms are stored in a packaging container formed by fusing two polymer films on top of each other or one polymer film in a folded state. ,
When stored refrigerated at 5℃,
After the sealing of the package, the internal carbon dioxide concentration is 4.7% or more and 6.0% or less in at least a part of the period from 2 days after the sealing of the package to 15 days after the sealing of the package. A package having an internal oxygen concentration of 15.9% or more and 17.5% or less in at least a part of the period from 2 days to 15 days after sealing the package. A package in which fruits and vegetables containing edible mushrooms are stored in a packaging container formed by fusing two polymer films on top of each other or one polymer film in a folded state. ,
When stored refrigerated at 5℃,
The internal carbon dioxide concentration 2 days after sealing the package and 15 days after sealing the package were both 3.5% or more and 8.0% or less, and 2 days after sealing the package and The package according to claim 1, wherein the internal oxygen concentration 15 days after the sealing is 14.0% or more and 18.0% or less. The package according to claim 1 or 2, wherein the generation of the odor of the edible mushroom can be suppressed for at least 15 days after the packaging is sealed. When refrigerated at 5℃,
The change rate of the internal carbon dioxide concentration is within 1.3% and the change rate of the internal oxygen concentration is within 1.6% from 2 days after the sealing of the package to 15 days after the sealing of the package. The package according to any one of claims 1 to 3. The package according to any one of claims 1 to 4, wherein nitrogen is enclosed in the packaging container. The oxygen permeability of the polymer film is 45,000 cc/m ² ·day·atm or more and 55,000 cc/m ² ·day·atm or less at 20° C. and 90% RH, and the packaging container has an opening area of 0.007. The package according to any one of claims 1 to 5, which has at least one or more micro holes of 0.11 mm ² . The package according to any one of claims 1 to 6, wherein the polymer film has a thickness of 15 to 45 µm. The package according to any one of claims 1 to 7, wherein the polymer film is a stretched polypropylene film, a polyethylene film, or a laminate of a stretched film and a polyethylene film. 9. The polymer film according to claim 1, wherein the polymer film contains an antifogging agent and also contains at least one antibacterial agent or is coated with at least one antibacterial agent. Packaging. The package for keeping freshness of fruits and vegetables according to any one of claims 1 to 9, further containing a moisture absorbent and/or an antibacterial agent. The package for keeping freshness of fruits and vegetables according to any one of claims 1 to 10, wherein the edible mushroom is shiitake or shimeji mushroom.