JP2018167900A - Package suited to retain freshness of fruit and vegetables, and method for retaining freshness of fruit and vegetables - Google Patents

Abstract

An object of the present invention is to control the water content of a package containing vegetables and fruits including cabbage in a packaging container to a specific amount from the viewpoint of the effect of the water content on the freshness of the cabbage, so that the cabbage can be packed at the time of packaging. For a long period of time, it is possible to extremely effectively suppress the generation of odor while suppressing the browning of the fruits and vegetables, and also suppress the increase in the number of viable bacteria. The task is to provide. SOLUTION: The package body contains vegetables and fruits including cabbage in a packaging container including a polymer film, and the cabbage has a water content of less than 23% when stored. [Selection diagram] None

Description

  The present invention relates to a package having excellent freshness retention performance of fruits and vegetables containing cabbage, and more specifically, containing fruits and vegetables containing cabbage in a packaging container having a polymer film and having a specific oxygen concentration. It relates to a package.

A gas permeable film that is provided with a gas permeable portion on a polymer film substrate and allows gas such as oxygen, carbon dioxide, and water vapor to pass through the gas permeable portion is used in the field of foods, particularly for fresh vegetables such as fruits and vegetables. It is suitably used as a packaging material. Using such a gas permeable film, for example, when packaging vegetables, fruits, etc., the oxygen concentration suitable for maintaining the freshness of the vegetables, fruits, etc., for example, an oxygen concentration of about 1 to 4% is maintained. It is known that contents can be stored while maintaining freshness over a relatively long period of time.
For example, in Patent Document 1, in a package containing fruits and vegetables made of a polymer film in which fruits and vegetables are sealed, the package is composed of (A) a porous polymer film and (B) a non-porous polymer film, The water vapor transmission rate measured under the conditions where the film characteristics of at least one of (A) and (B) are 25 ° C. and the relative humidity is 75% is 50 to 800 gm ⁻² d ^{−1 based} on the effective surface area of the package. There is described a packaged product with fruits and vegetables characterized in that the open area ratio of (A) is 3 × 10 ^{−6 to} 7 × 10 ⁻⁴ % with respect to the effective surface area of the package. Specifically, (A) a porous polymer film made of stretched polypropylene having a thickness of 35 μm, having 95 holes with an average pore diameter of 30 μm, 9 holes with an average pore diameter of 60 μm, etc. It is used.

Among fruits and vegetables, cabbage is one of the most widely distributed vegetables, and the packaging body and the storage method as described above can be suitably applied. In particular, cut cabbage cut from cabbage has increased in demand in recent years because it can be easily used for meals, and since cabbage is one of the most common vegetables for salads, it is highly economical. Have value. For this reason, a packaging body particularly suitable for maintaining the freshness of cut cabbage and a storage method have been actively studied. The oxygen transmission rate, carbon dioxide transmission rate, and water vapor transmission rate of the packaging body, and the oxygen concentration in the packaging body. It has been proposed to set the carbon dioxide concentration to specific values (for example, Patent Document 2).
However, even with the above technology, there may be cases where it is not possible to sufficiently achieve both the bad smell of cabbage and the suppression of browning, and consideration is given to the suppression of the number of viable bacteria that affects food safety, storage stability, hygienic handling, etc. However, there was a need for a solution.

JP-A-5-168400 JP 2004-242504 A

In view of the limitations of the background art described above, the present invention is a packaging in which fruits and vegetables containing cabbage are stored in a packaging container from the viewpoint of the effect of freshness given by the moisture content of cut vegetables (specifically, cut cabbage). It is a body and can suppress the browning of the fruits and vegetables containing the cabbage, and at the same time, can extremely effectively suppress the generation of odor, and can also suppress the increase in the number of viable bacteria, and is excellent in the freshness maintaining function of the fruits and vegetables It is an object of the present invention to provide a package.
In the present invention, in particular, in view of the actual situation of commerce, regarding a package formed by storing fruits and vegetables containing cabbage in a packaging container, after packaging of the cabbage, a condition of 2 ° C. or more and 15 ° C. or less, preferably about 10 ° C. Another object of the present invention is to provide a package that can both suppress the generation of brown odor and brown odor that affect the commercial value for a long time, and is excellent in suppressing the increase in the number of viable bacteria.

  As a result of diligent study, the present inventor, in a packaging body containing cabbage-containing fruits and vegetables in a packaging container containing a polymer film, by controlling the moisture content of cabbage during storage to a specific amount, The present inventors have found that the above problems can be solved and have completed the present invention.

That is, the present invention
[1]
A packaged body containing fruits and vegetables containing cabbage in a packaging container comprising a polymer film, wherein the amount of water when the cabbage is stored is less than 23%.
[2]
The package according to [1], wherein the inside of the packaging container is sealed with nitrogen.
[3]
[1] or [2] The generation of the odor of the cabbage can be suppressed for 96 hours or more under the condition of 10 ° C. after packaging, and the generation of the browning of the cabbage can be suppressed for 144 hours or more under the condition of 10 ° C. after packaging. The package described in 1.
[4]
The viable cell count of the cabbage can be suppressed for more than 168 hours under the condition of 10 ° C. after packaging, compared to the case where the water content at the time of storing the cabbage is 23%, according to any one of [1] to [3] Packaging.
[5]
The packaging according to any one of [1] to [4], wherein the polymer film has an oxygen permeability of 500 cc / m ² / day / atm to 30000 cc / day / atm at 20 ° C. and 90% RH. body.
[6]
The packaging body according to any one of [1] to [5], wherein the packaging container does not have a through hole that can be confirmed by an ink leakage checker.
[7]
The package according to any one of [1] to [6], wherein the polymer film has a thickness of 15 μm or more and 45 μm or less.
[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 package according to any one of [1] to [8], wherein the polymer film contains at least one antibacterial agent or is coated with at least one antibacterial agent.
[10]
The package for keeping freshness of fruits and vegetables according to any one of [1] to [9], further containing a hygroscopic agent and / or an antibacterial agent.
[11]
A method for maintaining the freshness of fruits and vegetables under conditions of 2 ° C or higher and 15 ° C or lower, comprising the step of storing fruits and vegetables containing cabbage having a moisture content of less than 23% in a packaging container comprising a polymer film.
[12]
The method for maintaining freshness of fruits and vegetables according to [11], further comprising a step of enclosing nitrogen in the packaging container.

According to the present invention, in a packaging body containing cabbage-containing fruits and vegetables in a packaging container, by controlling the moisture content of the cabbage to be stored to a specific amount, for a long time from the time of its enclosure, its off-flavor, browning, And it is possible to effectively suppress the total number of viable bacteria. Therefore, according to the present invention, the package of fruits and vegetables containing the cabbage and the method for keeping freshness can produce an effect that the freshness keeping function of the fruits and vegetables is excellent.
According to the present invention, in particular, with respect to a package formed by storing fruits and vegetables containing cabbage in a packaging container, after packaging of the cabbage, the condition is 2 to 15 ° C., preferably about 10 ° C. for a long time, It can both prevent the generation of off-flavors and browning that affect product value, and can provide a package that is also excellent in suppressing the increase in the number of viable bacteria, and has high commercial value in commercial transactions. There is an effect.

Hereinafter, modes for carrying out the present invention will be described.
The present invention is a packaging body in which fruits and vegetables containing cabbage are stored in a packaging container containing a polymer film, and the water content when the cabbage is stored is less than 23%. Thus, the package of this invention has a packaging container and the fruit and vegetables accommodated there at least.
The numerical range in the present application includes a lower limit value and an upper limit value unless otherwise specified. Therefore, for example, the expression “500 to 30000 cc / day / atm” means 500 cc / day / atm or more and 30000 cc / day / atm or less unless otherwise specified.

Packaging container The packaging container which comprises the package of this invention comprises a polymer film. Here, “comprising a polymer film” means that when the entire packaging container is made of a polymer film and when a part of the packaging container such as a lid is made of a polymer film, It is intended to include both.
Therefore, the packaging container may be a flexible packaging container, or a so-called packaging bag, whose whole or main part is 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 are combined, or a packaging container in which a flexible polymer film and a rigid member are combined, for example, as a lid material. It may be in the form of a combination of a molecular film and a rigid member such as a tray or cup.

In an embodiment in which the packaging container is a so-called packaging bag, for example, three or two sides are heat-sealed in a state where two polymer films are overlapped with each other or one polymer film is folded. A packaging bag can be formed by, for example, fusing. The remaining one side can be sealed by arranging the contents such as fruits and vegetables in the packaging bag and then fusing it by heat sealing.
Such a packaging bag may have a circular shape, a triangular shape, a quadrangular shape, or a polygonal shape equal to or more than a quadrangular shape in a plan view, but is preferably rectangular from the viewpoint of processability and ease of handling.

  The packaging container used in the present invention comprises the polymer film described above, and its oxygen permeability is not particularly limited. The amount and type of fruits and vegetables to be stored and after a predetermined time has elapsed after packaging. An appropriate oxygen permeability can be selected in accordance with a desired internal oxygen concentration. Usually, what is in the range of 500-30000cc / day / atm in 20 degreeC and 90% RH can be used preferably.

Vegetables and Fruits The package of the present invention contains fruits and vegetables containing cabbage in the packaging container. Here, the phrase “contains cabbage” means that both the case where all of the fruits and vegetables are made of cabbage and the case where some of the fruits and vegetables are made of cabbage are included. Therefore, the fruits and vegetables stored in the packaging container may or may not contain other vegetables and fruits. Furthermore, as long as cabbage is included, ingredients other than fruits and vegetables, for example, foods other than fruits and vegetables, seasonings, food additives and the like may be included.
Moreover, the cabbage (contained in the packaging container) constituting the package of the present invention is preferably a cabbage adjusted to an appropriate amount of water by cutting, washing, dehydrating or drying.

The “cabbage” constituting the package of the present invention (contained in the packaging container) is a concept including general headed vegetables belonging to the Brassicaceae genus Brassica, and is limited to vegetables distributed under the name of “cabbage” itself. Not.
That is, “cabbage” here is, as a preferable example, cold ball (winter) cabbage, spring cabbage, plateau cabbage, red cabbage, green ball (round ball), savoy cabbage (chirimen cabbage), Brussels sprouts, petit veil, There are bamboo shoot-type cabbages such as Misaki Kanai and Tongari cabbage (but not limited to), and the concept encompasses all of these.

The cabbage (contained in the packaging container) constituting the package of the present invention has a moisture content of less than 23% when stored. This water content is preferably 7% or more and less than 23%, and preferably 9% or more and 22% or less, in terms of coexistence of suppression of cabbage odor and browning over a long period of time and suppression of the number of viable bacteria. More preferably, it is 9% or more and 21% or less, still more preferably 9% or more and 15% or less, and particularly preferably 9% or more and 12% or less.
In commercial transactions, the cabbage texture may be emphasized. However, when the amount of water in the cabbage is reduced, the texture as a fresh cabbage may be reduced even when it is excellent in suppressing the off-flavor and browning. When maintaining both the cabbage odor and browning for a long period of time while maintaining the texture of fresh cabbage, the moisture content is 12% when viewed comprehensively. It is preferably 20% or less and more preferably 15% or more and 19% or less. The amount of water in this range is excellent in that it can effectively suppress the bad smell, browning, and viable count of cabbage while maintaining the fresh texture of the cabbage for a long time.
The moisture content in the present application refers to zero (starting point) of a sample that has been dried under reduced pressure for 5 hours at 70 ° C. based on “Analysis method for nutrition labeling according to nutrition labeling standards” (Consumer Agency). Say that from the weight. For example, when 100 g of cut cabbage becomes 90 g by drying under reduced pressure at 70 ° C. for 5 hours, the water content is 10 g / 100 g = 10%.

  Control of the water content of the cabbage during storage is performed by a drying process by draining water, but the process is not limited to this process as long as the object can be achieved. Examples of the dehydration or drying treatment by draining include, for example, a method by centrifugation, shaking, wind, absorption by a hygroscopic agent (drying agent), or a method by a combination of two or more thereof. However, the present invention is not limited to these methods.

There is no restriction | limiting in particular in the form of the cabbage which comprises the package body of this invention (it accommodates in a packaging container). It may be as-harvested, so-called pre-treated from which outer leaves or the like have been removed, or in a cut form called cut cabbage.
The shape of the cabbage may be subjected to processing such as slicing in addition to cutting, and is not limited to the processing method within the scope of the present invention. Therefore, specifically, forms such as chopped and shredded are also included.
Moreover, the cabbage (contained in the packaging container) constituting the package of the present invention may be one obtained by performing any or all of the processes such as washing, cooling and dehydration within the scope of the present invention. In addition, none of these processes may be performed.

In the present invention, when cabbage is stored in the packaging container, there is no particular limitation on other fruits and vegetables that can be stored together, and unheated or heated fruits and vegetables that can be used for food together with the cabbage can be appropriately stored. Specific examples of such fruits and vegetables include bananas, mangoes, ume, apples, strawberries, mandarin oranges, grapes, Japanese pears, fruit like Western pears, carrots, Chinese yam, root vegetables like burdock, tomatoes, cucumbers, Fruit vegetables such as eggplant, bell pepper, green beans, okra, sprouts such as mung bean sprout, soybean sprout, cypress, fungi such as shiitake mushroom, shimeji mushroom, eringi, maitake, matsutake, broccoli, spinach , Leaf stem vegetables such as Komatsuna, Chingensai, Japanese radish, lettuce, asparagus, florets or seedlings, but is not limited thereto.
In the case of storing cabbage, the form in which the oxygen concentration is controlled and held, which is one form of the present embodiment, is particularly effective for maintaining the freshness of fruits and vegetables that are substantially breathing.

In this invention, there is no restriction | limiting in particular also in the form of the other fruits and vegetables which can be accommodated with a cabbage in a packaging container. Therefore, the fruits and vegetables containing cabbage may be as-harvested or so-called pre-treated from which outer leaves have been removed, so-called cut vegetables (cut cabbage) that have been cut. It may be. In addition, the fruits and vegetables may be those that have been subjected to any or all of the treatments such as washing, cooling, and dehydration, and may be those that do not perform any of these treatments.
In addition, when the cabbage that is stored and kept fresh is cut cabbage, it is preferable to perform cutting, washing, dehydration, or drying to adjust the moisture content to an appropriate level. Specifically, the cut cabbage is washed with 80 to 120 ppm for 10 to 20 minutes of hypochlorous acid based on the “Manufacturing Sanitation Management Manual” (Ministry of Health and Welfare). The amount of water measured based on weight loss when dried under reduced pressure at 70 ° C for 5 hours based on the Consumer Affairs Agency), balance between prevention of odor generation and deterioration of appearance such as browning, and number of viable bacteria From the viewpoint of suppression, the range is less than 23%, preferably 7% or more and less than 23%, more preferably 9% or more and 22% or less, and 9% or more and 21% or less. More preferably, it is more preferably 9% or more and 15% or less, and particularly preferably 9% or more and 12% or less. Furthermore, considering the balance including maintaining the texture of cabbage, the water content is preferably 12% or more and 20% or less, and more preferably 15% or more and 19% or less.

The demand for cut vegetables has increased in recent years because it can be easily used for meals, and its commercial value is high, and thus has high economic value. Cut cabbage is representative of cut vegetables, and those that are mixed as they are can be used for meals as salads and the like, and thus have particularly high economic value. On the other hand, cabbage generally has a tendency that the respiratory action and metabolic reaction are rapidly activated and the quality is rapidly lowered by being cut. For this reason, cut cabbage tends to have a bad influence on the commercial value, browning, and increase in the number of viable bacteria with the passage of time. Among them, off-flavors are said to be particularly strong compared to other general vegetables, and have a great influence on the commercial value. However, this embodiment can effectively suppress this off-flavor, and can therefore be used effectively for maintaining the freshness of cut cabbage in combination with browning and suppression of the number of viable bacteria.
The viable cell count usually means the mesophilic aerobic viable cell count that grows under a certain condition, and is the most representative index indicating the degree of microbial contamination of food. Used for comprehensive evaluation and judgment of food safety, storage stability, hygienic handling, etc. In general, the number of colonies was calculated after culturing at 35 ° C. ± 1.0 ° C. for 48 hours ± 3 hours under aerobic conditions using a standard agar medium. Said.

  The preferred oxygen concentration for maintaining freshness varies depending on the type and form of cabbage (contained in the packaging container) constituting the package of the present invention, and accordingly, within the scope of the present invention, oxygen permeability, and The mode of the polymer film that gives an appropriate oxygen permeability can be selected as appropriate. By appropriately setting these, it is possible to maintain effective freshness within the scope of the present invention for both the cabbage and the fruits and vegetables stored together.

Packaging Body The internal oxygen concentration of the packaging body of the present invention is not particularly limited as long as the object of the present invention can be achieved, but usually maintains an oxygen concentration of more than 0% by volume to 0.5% by volume or less. It is desirable to do so.
The temperature condition for placing the package of the present invention is not particularly limited as long as the object of the present invention can be achieved, but it is preferably 2 ° C. or higher and 15 ° C. or lower, more preferably 10 ° C. in view of the actual situation of commercial transactions. .
The oxygen concentration inside the package can be specified, for example, by measuring the oxygen concentration with a food packaging O ₂ / CO ₂ analyzer Check Mate 3 manufactured by Dansensor.
Here, “after packaging” refers to the time elapsed since the packaging container was sealed after the vegetables and fruits containing cabbage were stored in the packaging container. For example, “after 3 days after packaging” After the cabbage is stored inside, the packaging container is sealed, and after 3 days have passed (that is, after 72 hours have passed).

  From the viewpoint of realizing the above-described desired internal oxygen concentration, the inside of the packaging container is preferably sealed with nitrogen. This is because the internal oxygen concentration immediately after packaging can be eliminated by sealing with nitrogen and saturating the packaging container. Moreover, since the pressure in the packaging container can be kept high by further enclosing nitrogen, the inflow of outside air with a higher oxygen concentration is prevented, and the internal oxygen concentration is 0.5 vol% or less for a long time after packaging. Can be kept low.

In addition, in order to realize the above-described desired internal oxygen concentration, it is desirable to configure the packaging container using a polymer film having an oxygen permeability of a predetermined value or more.
That is, the lower limit value of the oxygen permeability of the polymer film used in the present invention is preferably 500 cc / m ² / day / atm or more at 20 ° C. and 90% RH, and more than 800 cc / m ² / day / atm. Is more preferably 1000 cc / m ² / day / atm or more, and further preferably 5000 cc / m ² / day / atm or more. When the oxygen permeability at 20 ° C. and 90% RH is 1000 cc / m ² / day / atm or more, oxygen from the outside air is introduced and can be maintained at a desired internal oxygen concentration. Specifically, the internal oxygen concentration in the packaging container saturated with nitrogen at the time of sealing can be maintained at an internal oxygen concentration of more than 0% by volume for at least 6 days (144 hours) after packaging. The upper limit value of the oxygen permeability of the polymer film used in the present invention is not particularly limited, but is preferably 30000 cc / m ² / day / atm or less at 20 ° C. and 90% RH, and 15000 cc / m ^2. / more preferably day / atm or less, more preferably less ^{10000cc / m 2 / day / atm} , more preferably not more than ^{5000cc / m 2 / day / atm} , 3000cc / m 2 / day More preferably, it is at most / atm.

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 220 mm × 240 mm is formed by the following method.
One film is folded almost equally into two, approximately 5 mm wide, and heat sealing is performed with an impulse sealer (manufactured by Fuji Impulse Co., product number Fi-200-10WK) with the heating condition scale set to 3, and the heat sealing is performed. Heat seal the whole of one side that is almost perpendicular to the heat seal side so that the side is almost in the center, except the end of about 2 cm that is one communicating part of the other side, and the inner dimension is 220 mm × A 240 mm bag is formed.
Next, nitrogen gas is injected from the communication portion, and when the inside of the bag becomes saturated, almost all the gas in the bag is discharged from the communication portion. After repeating this operation five times, nitrogen gas is injected to saturate the inside of the bag with nitrogen gas, and the communicating portion is heat-sealed with the impulse sealer under the same conditions. The bag saturated with nitrogen gas is left in a room at 22 ° C. and 40% relative humidity in air (1 atm, oxygen concentration: 21%, nitrogen concentration: 79%) for 6 hours.
The oxygen concentration inside the bag is specified, for example, by measuring the oxygen concentration with a Dansensor O ₂ / CO ₂ analyzer for food packaging, Check Mate 3. Furthermore, the volume of the gas in the bag is measured, and the oxygen permeability is calculated from the following formula.
(Expression) Oxygen permeability = change in internal oxygen concentration (%) / 100 × volume (cm ³ ) × 24 × 60 / hour (360 minutes) × 10000 cm ² / area (1232 cm ² ) /0.21 (partial pressure of oxygen )

By appropriately selecting the material, thickness, processing method and the like of the polymer film, the oxygen permeability of the polymer film can be adjusted as appropriate.
For example, the oxygen permeability of a 30 μm OPP (biaxially oriented polypropylene) bag is 1000 cc / m ² / day / atm, but if one 100φ hole is made, it becomes 2000 cc / m ² / day / atm. Considering the mechanical strength and the like, the thickness of the polymer film is more preferably 15 to 45 μm, and particularly preferably 20 to 40 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. It is not necessary to provide an opening in the polymer film. In particular, the oxygen permeability of 1000 cc / m ² / day / atm or higher at 20 ° C. and 90% RH in a preferred embodiment of the present invention can be realized without providing an opening in the polymer film.
Since it is not necessary to provide an opening in the polymer film, the manufacturing process is simpler and less expensive, and it is not necessary to precisely control the size, shape, etc. of the opening.
The absence of an opening in the polymer film can be confirmed, for example, by the fact that the polymer film constituting the packaging container does not have a through-hole that can be confirmed with an ink leak checker.

On the other hand, in one embodiment of the present invention, when it is necessary to use a thick polymer film or a polymer material having a low oxygen permeability, the polymer film is used to achieve a desired oxygen permeability. You may use together the opening provided in. The shape of the opening is not particularly limited, and may be circular, substantially circular, or may be slit. 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 substances 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. In that case, the openings occupying the effective area of the polymer film The number of For example, a slit-like opening having a length of 2 mm, and in the closed state, the width as a through-hole cannot be visually recognized with an optical microscope (Olympus, model SZH-131) at a magnification of 4 times. When a product is provided, there is an effect of increasing the oxygen permeability of about 1000 cc / m ² / day / atm for every 200 mm × 200 mm packaging container. Packaging required based on such knowledge It is preferable to determine the number of slit openings from the oxygen permeability of the entire container.

  There is no particular limitation on the thickness of the polymer film used in the present invention, and when an opening is provided such as suitable oxygen permeability, flexibility when forming a packaging container, strength, transparency, economy, etc. From the viewpoint of accuracy and ease in forming the part, a suitable thickness may be selected as appropriate in relation to the material forming the polymer film. Typically, the thickness of the polymer film is preferably 10 to 45 μm, more preferably 20 to 40 μm, still more preferably 15 to 35 μm, and particularly preferably 18 to 32 μm. .

  Although there is no restriction | limiting in particular in the material of the said polymer film, The polymer used for the film for conventional fruit and vegetables packaging can be used suitably. 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, natural polymers 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 polymer film is preferably made of 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, ethylene polymers such as high pressure method low density polyethylene, linear low density polyethylene (LLDPE), high density polyethylene, propylene homopolymer, propylene / α-olefin random copolymer, propylene block copolymer. And propylene-based polymers such as poly 1-butene and poly 4-methyl / 1-pentene. The thermoplastic resin includes polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyamides such as nylon-6, nylon-66, polymetaxylene adipamide, polyvinyl chloride, polyimide, ethylene / acetic acid. Examples thereof include a vinyl copolymer or a saponified product thereof, polyvinyl alcohol, polyacrylonitrile, polycarbonate, polystyrene, ionomer, polylactic acid, polybutylene succinate and the like, 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 are excellent in rigidity and transparency. Further, as the thermoplastic resin, an ethylene polymer and a propylene polymer are more preferable because they are lightweight and excellent in film processability, and a propylene polymer is more preferable from the viewpoint of flexibility and transparency.

<Propylene polymer>
Examples of the propylene polymer include a propylene homopolymer (also referred to as homo PP) manufactured and sold under the name of polypropylene, and a propylene / α-olefin random copolymer (also referred to as random PP). And crystalline polymers mainly composed of propylene such as a mixture of propylene homopolymer and low crystalline or amorphous propylene / ethylene random copolymer (also called block PP). . Further, the propylene-based polymer may be a mixture of propylene homopolymers having different molecular weights, and is composed of 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 polymer include polypropylene, propylene / ethylene copolymer, propylene / ethylene / 1-butene copolymer, propylene / 1-butene copolymer, and propylene / 1-pentene copolymer. Copolymer of propylene such as propylene / 1-hexene copolymer and propylene / 1-octene copolymer as a main monomer and at least one selected from ethylene and α-olefin having 4 to 10 carbon atoms Coalescence is mentioned. These may use 1 type and may use 2 or more types together.

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 propylene-based polymer MFR (ASTM D1238 load 2160 g, temperature 230 ° C.) is preferably 0.5 to 60 g / 10 minutes, more preferably 0.5 to 10 g / 10 minutes, and more preferably 1 to 5 g / 10 minutes. Is more preferable.

<Ethylene polymer>
Examples of the ethylene polymer include a homopolymer of ethylene, a copolymer of ethylene as a main monomer and at least one α-olefin having 3 to 8 carbon atoms, an ethylene / vinyl acetate copolymer, Saponifications 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 thereof include copolymers of ethylene as a main monomer, such as a copolymer and an ethylene / 1-octene copolymer, and at least one kind of an 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 method 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 polymer may be an ethylene homopolymer 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. Moreover, when the density is 0.940 g / cm ³ or less, workability and transparency are improved.

  The blend and / or laminate may be a blend and / or laminate of any of the above polymers, and any of the above polymers and a material other than the polymer. Blends and / or laminates. That is, the polymer film is a material other than a polymer, such as 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 and dyes, various fillers such as talc, silica, and diatomaceous earth may be included, or a laminate of a polymer film and metal foil, paper, nonwoven fabric, or the like may be used.

In the present invention, the polymer film constituting the packaging container may be an unstretched film or a stretched film.
From the viewpoint of mechanical strength and the like, stretched films of various polymers can be suitably used.
In particular, a stretched film (stretched polypropylene film) using a propylene-based polymer is excellent in mechanical strength, transparency, heat resistance and the like, and therefore can be particularly preferably used in the packaging container used in the present invention.
Further, the film using the ethylene polymer (polyethylene film) may be either a non-stretched film or a stretched film, but a non-stretched film is particularly preferably used from the viewpoint of heat sealability and the like. be able to.
Examples of the polymer film that is particularly suitable as the polymer film constituting the packaging container in the present invention include a stretched polypropylene film, a polyethylene film, and a laminate of the stretched film and the 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. Moreover, when obtaining a biaxially stretched film as a stretched polypropylene film, it can also be easily manufactured 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 stretched 8 to 10 times in the transverse direction using a tenter mechanism, and the film thickness is finally adjusted. Or 20 to 40 μm, or by stretching 5 to 10 times (25 to 100 times in terms of surface magnification) in the longitudinal direction and the transverse direction, respectively.
<Polyethylene film>
The polyethylene film preferably used in the present invention is a film containing the ethylene polymer. Various known molding methods can be used for the polyethylene film, but cast molding by extrusion using an extruder is preferred from the viewpoint of production efficiency.

<Stretched film>
Polyamide film made of nylon 6, nylon 66, etc., film made of polyester represented by polyethylene terephthalate, polyethylene naphthalate, polycarbonate film, ethylene / vinyl alcohol copolymer film, polyvinyl alcohol film, polyvinyl chloride film, polyvinylidene chloride Films, polystyrene films, polyolefins such as polypropylene, and poly-L lactic acid, poly-D lactic acid, or uniaxial or biaxially stretched films composed of stereocomplex crystal polylactic acid in which poly-L lactic acid and poly-D lactic acid are coordinated precisely.

<Laminated body of stretched film and polyethylene film>
A laminate of a stretched film and a polyethylene film preferably used in the present invention is obtained by laminating the polyethylene film layer and the stretched film layer. The polyethylene film may be stretched in one or two directions, but is preferably an unstretched film from the viewpoint of the stability of the mechanical strength of the packaging bag.
Dry lamination is performed by adhering a stretched film and a polyethylene film prepared in advance with an adhesive. From the viewpoint of adhesion stability, the surface of the stretched film to which the adhesive is applied should be corona treated. preferable. Specifically, the surface tension of the film surface after the corona treatment is preferably 35 mN / m or more, more preferably 40 mN / m or more, from the viewpoint of adhesion stability.

These polymer films may be stretched, antifogged or printed, and include inorganic antibacterial agents such as silver and copper, and organic antibacterial agents such as chitin, chitosan, and allylisothiocyanate. The agent may be applied, or these may be kneaded in 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.
Further, a specific amount of a specific surfactant is present on the surface of the polymer film, or the polymer film may have a specific amount of a specific surfactant to have an antibacterial function. For example, it is preferable that at least one compound selected from the group consisting of palmityl diethanolamine, stearyl diethanolamine, glycerol monolaurate and diglycerol monolaurate is present on at least one surface of the polymer film, it is particularly preferred that one compound 0.002~0.5g / ^{m 2} is present. Alternatively, the polymer film preferably contains at least one compound selected from the group consisting of palmityl diethanolamine, stearyl diethanolamine, glycerol monolaurate, and glycerol monocaprate, 0.001 to 3 parts by mass It is particularly preferable to contain.
When a specific amount of a specific surfactant is present 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, Suppression of the growth of bacteria suppresses the growth of germs in the dew (drip) and exhibits an antibacterial function.

From the viewpoints of transparency, flexibility, cost, etc., it is particularly preferable to use a stretched polypropylene film or a laminate of a stretched polypropylene film and a polyethylene film that has been widely used in the art as a polymer film. . Since these films are generally excellent in heat sealability, productivity is good in the production of packaging containers.
When using a stretched propylene film alone, the thickness is preferably 10 to 100 μm. When using a laminate of a stretched polypropylene film and a polyethylene film, the former has a thickness of 10 to 50 μm and the latter The thickness is preferably 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. Examples thereof include a cellophane film coated with an acrylic resin and a film obtained by laminating polyethylene terephthalate (PET) with linear low density polyethylene (LLDPE) polystyrene and EVA, and these can be used as suitable polymer films.

The present invention relates to a method for producing a package, and a method for maintaining freshness.The present invention stores the fruits and vegetables containing cabbage in a packaging container containing a polymer film, and appropriately adjusts the amount of water the cabbage has when stored. Can be produced, and the method for maintaining the freshness of fruits and vegetables, which is an embodiment of the present invention, can be implemented.
Hereinafter, the manufacturing method of the package of the present invention will be described using a package for keeping freshness made of cut cabbage as an example.

  First, in the pretreatment step, the cabbage is removed manually, removed into 2 to 4 parts, and the core is removed, and the cabbage is supplied to the conveyor. The cabbage transported by the conveyor is cut with a slicer, washed with cooling water in a washing tank filled with cold water, and drained with a centrifugal dehydrator, dry air, etc. after draining so that the water content is less than 23%. . The dehydrated cut cabbage is packed in a packaging container (not sealed on one side) containing the polymer film used in this embodiment, and after packaging, the packaging container is sealed to maintain the freshness of the cut cabbage. A package is produced.

  The cut cabbage dehydrated in the pretreatment step described above is weighed to a predetermined amount, and packed in a packaging container (not sealed on one side) containing a polymer film used in the present embodiment. The packaging container is sealed, and a freshness-maintained packaging body in which cut cabbage is stored (packaged) is manufactured.

From the viewpoint of maintaining the freshness of the cut cabbage, it is preferable to use a sharp blade and reduce the number of scratches on the cut surface.
In addition, as the cut width is narrower, the cutting area increases and it becomes more difficult to maintain freshness. From the viewpoint of maintaining freshness, it is preferable that the cut width is wider as long as it matches the form of demand.
Furthermore, if a lot of germs are attached to the cut cabbage from the beginning, it is more difficult to maintain freshness. Therefore, it is preferable to reduce the adherence of germs as much as possible by washing well. Washing is particularly effective for maintaining freshness because it not only reduces the adhesion of various bacteria, but also has the effect of removing cell fluids and the like that contain highly active enzymes and the like and can cause discoloration.
In addition, it is important for maintaining freshness to sufficiently remove the water adhering to the surface of the cut cabbage after washing, and in the cut cabbage, the amount of water needs to be reduced to less than 23%, Of particular importance. Even if the water is drained by standing after washing, there is often a lot of water adhering to the surface of the cut cabbage, so remove water sufficiently using a centrifugal dehydrator, etc. and dry with dry air. It is effective to do. This is because the growth of miscellaneous bacteria due to extra fine water droplets can be suppressed. More specifically, according to the “Manufacturing Sanitation Management Manual for Large-scale Cooking Facilities” (Ministry of Health and Welfare), after 80-120 ppm for 10-20 minutes of hypochlorous acid cleaning, “Analytical Methods for Nutrition Labeling in Nutrition Labeling Standards” (Consumer Agency) Based on the above, it is particularly preferable that the water content measured based on the weight loss when dried under reduced pressure at 70 ° C. for 5 hours is less than 23% from the viewpoint of suppressing odor and preventing appearance deterioration such as browning.

The package for freshness preservation of fruits and vegetables of this embodiment is a container for fruits and vegetables containing cabbage (preferably cabbage that has been cut, washed, dehydrated or dried and adjusted to an appropriate amount of water) and sealed in a packaging container. Later, nitrogen filling and / or degassing may be performed. By performing nitrogen sealing and / or degassing, it becomes possible to quickly reach a desired oxygen concentration designed as an equilibrium state between the oxygen permeability of the packaging container and the respiration rate of fruits and vegetables, which is advantageous for maintaining freshness. .
In addition, deaeration may be performed after sealing the packaging container from the viewpoint of improving efficiency in the process of distribution, saving space, and eliminating a specific gas.

  In accordance with the method as described above, for example, after carrying out the step of storing fruits and vegetables containing cut cabbage having a water content of less than 23% in a packaging container comprising a polymer film, the oxygen concentration in the packaging container is packaged. After that, the freshness of the fruits and vegetables including the cut cabbage can be effectively maintained by maintaining the content at more than 0% by volume to 0.5% by volume or less over 10 days (144 hours) at 10 ° C.

The package of the present invention may contain only fruits and vegetables including cabbage in the packaging container, or may contain other members.
For example, in addition to fruits and vegetables, a hygroscopic agent and / or an antibacterial agent may be stored in the packaging container.
There is no limitation in particular in a moisture absorbent, The well-known or commercially available material which has a moisture absorption effect or a humidity control 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 calcined alum, or a mixture thereof. For example, but not limited to.
Among these, it is particularly preferable to use activated carbon which has relatively little concern about the influence on fruits and vegetables and the use of fruits and vegetables near foods. The activated carbon can be either powdered or granular, and the raw material can be anything from coconut husk, sawdust, charcoal, bamboo charcoal, lignite, peat, diamond, and petroleum pitch. The activated carbon is preferably wrapped in non-woven fabric, cellophane, paper, etc. for each unit used, but the activated carbon itself may be in the form of a fiber. The activated carbon packaging material is preferably a heat-sealable material such as a non-woven fabric made of a synthetic resin. However, any material such as paper or natural fiber can be used as long as it has water vapor permeability and does not spill activated carbon. no problem.

  There is no particular limitation on the antibacterial agent, and a substance having an antibacterial action can be used as appropriate, but a natural antibacterial agent with relatively little concern about the effect on fruits and vegetables and use in the vicinity of fruits and vegetables as foods. It can be preferably used. More specifically, natural antibacterial agents such as chitosan, allyl isothiocyanate, hinokitiol, limonene and the like can be stored in the packaging container.

  Hereinafter, the present invention will be specifically described with reference to Examples / Comparative Examples. It should be noted that the present invention is not limited in any way by the following examples.

In the following examples / comparative examples, each characteristic was evaluated by the following method.
(With or without opening)
After injecting the red penetrant (Mitsubishi Gas Chemical Co., Ltd., trade name: Ageless Seal Check Spray) into the packaging container, set the scale of the heating condition to 3 with an impulse sealer, heat seal with a width of about 5 mm, and paper (Kokuyo PPC paper, common paper A4) was pressed and the presence or absence of an opening was confirmed by the presence or absence of the transfer of the ink to paper.
(amount of water)
As described above, the moisture content in the cabbage stored in the packaging container was dried at 70 ° C. under reduced pressure for 5 hours based on the “analysis method of nutrition labeling according to nutrition labeling standards” (Consumer Agency). The sample was defined as zero (starting point) and the weight from there. For example, when 100 g of cut cabbage becomes 90 g by drying under reduced pressure at 70 ° C. for 5 hours, the water content is 10 g / 100 g = 10%.
(Oxygen concentration and carbon dioxide concentration)
The measurement was performed using an O ₂ / CO ₂ analyzer, Check Mate 3, for food packaging manufactured by Dansensor.
(appearance)
The package was opened, the cabbages taken out were arranged, and the area of the entire browned portion was visually evaluated with n (number of samples) = 5 around the cut cross section.
The evaluation criteria are as follows.
A: No problem in fresh state B: Slightly browned but can be said to be fresh C: Browned but in the same state as commercially available D: Further browning is strong and consumers care E: Further browning and unsellable state In this application, it was evaluated that browning occurred in the case of evaluation of C, D, and E, and it was evaluated that browning that lost commercial value in the case of D and E occurred. did.
(odor)
When the package was opened, the face was brought close to it and the inner odor was smelled, and n (number of samples) was evaluated as 5 (sensory evaluation).
The evaluation criteria are as follows.
A: There is no problem in the fresh state B: There is a little smell but it can be said that it is fresh C: The state is strong but it is in the same state as the market and can be sold D: The state is more smelly and the consumer cares E: Stronger odor and unsaleable In addition, in this application, it is evaluated that a bad odor has occurred in the case of evaluation of C, D and E, and a bad odor which loses commercial value in the case of D and E has been evaluated. did.
(Viable count)
The number of viable bacteria was measured under aerobic conditions using a standard agar medium for n (sample number) = 5 on the 4th day (96 hours later) and 7th day (168 hours later) after packaging of cut cabbage. The number of colonies observed after culturing at 35 ° C. ± 1.0 ° C. for 48 hours ± 3 hours (unit: CFU / g) was calculated.

Example 1
Two OPP (biaxially stretched polypropylene) films with a thickness of 30 μm are overlapped, three sides are sealed with heat sealing and cut, and one side is unsealed packaging bag (170 mm × 235 mm, inner dimension Area: 799 cm ² ).
When the presence or absence of an opening in the film was confirmed, it was confirmed that there was no opening.
Regarding the gas permeation of the film, the oxygen permeability was 1000 cc / m ² / day / atm at 20 ° C. and 90% RH.
The oxygen concentration was maintained at a low concentration of 2% by volume or less during the measurement period.
The cut cabbage used in this example was produced as follows.
After removing the cabbage stains and scratched parts, it was cut into a width of approximately 2 mm and washed with 100 ppm for 10 minutes in hypochlorous acid based on the “Manufacturing Sanitation Management Manual” (Ministry of Health and Welfare). Thereafter, dehydration and drying were appropriately performed to produce cut cabbage.
In addition, as described above, cut cabbage moisture content is measured based on the weight loss when dried under reduced pressure for 5 hours at 70 ° C based on "Analysis method for nutrition labeling according to nutrition labeling standards" (Consumer Agency). did. As a result, the water content was 9% as shown in Table 1.
50 g of cut cabbage having the moisture content shown in Table 1 was stored in the packaging container, and the container was completely filled with nitrogen, and then heat sealed to prepare a package. The package was stored at 10 ° C., and the internal oxygen concentration and carbon dioxide concentration were measured every day for 6 days under the condition of 10 ° C. from the cut cabbage packaging, and the odor and appearance of the cut cabbage were evaluated. The results are shown in Table 1.
Further, the viable cell count (unit: CFU / g) on the 4th and 7th days from the cut cabbage packaging was examined.

(Examples 2-3)
According to the "Manufacturing Sanitation Management Manual for Large-scale Cooking Facilities" (Ministry of Health and Welfare), after passing through the steps of 1 cut, 2 washing to water washing, the 3 dehydration process is performed as "analysis method for nutrition labeling according to nutrition labeling standards" (consumption The amount of water was 12% by adjusting the dehydration conditions and drying conditions using a dehydrator and a drier with zero (starting point) as a sample that had been dried under reduced pressure at 70 ° C for 5 hours based on the Each cut cabbage of Example 2) and 15% (Example 3) was obtained, and a package was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 1)
According to the "Manufacturing Sanitation Management Manual for Large-scale Cooking Facilities" (Ministry of Health and Welfare), after passing through the steps of 1 cut, 2 washing to water washing, the 3 dehydration process is performed as "analysis method for nutrition labeling according to nutrition labeling standards" (consumption The amount of water was 23% by adjusting the dehydration conditions and the drying conditions using a dehydrator and a drier with zero (starting point) as a sample that had been dried at 70 ° C for 5 hours under reduced pressure based on the Cut cabbage was obtained, and a package was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

In Examples 1 to 3, where the moisture content of the cut cabbage when stored in the packaging container is within the range of less than 23%, the odor is evaluated by A or B even on the fourth day (after 96 hours) from the packaging. Although it can be said that the fresh state is maintained, it is possible to suppress the off-flavor that may affect the commercial value with the evaluation of C or higher, although the off-flavor has occurred even on the fifth day (after 120 hours) from the packaging. confirmed.
In Examples 1 to 3, it was also confirmed that the appearance (browning) maintained a fresh state by A or B evaluation even on the sixth day (after 144 hours) from the packaging.
On the other hand, in Comparative Example 1 in which the moisture content of the cut cabbage when stored in the packaging container was 23%, although it was C evaluation, a bad odor was generated on the third day (72 hours later) after packaging. On the 4th day (96 hours later), it was confirmed that an unpleasant odor that consumers of D evaluations worried generated and lost commercial value.
In addition, about the external appearance (browning) of the comparative example 1, it was confirmed by the A or B evaluation also on the 6th day (after 144 hours) from packaging that the fresh state is maintained like an Example.
For this reason, as in Comparative Example 1, when the moisture content of the cut cabbage when stored in the packaging container is 23%, an odor is generated on the third day (after 72 hours) from the packaging. Although it does not lose value, it cannot be said that it is possible to achieve both odor and suppression of browning, and on the fourth day (after 96 hours) after packaging, it gives off a strange odor that consumers are concerned about. On the other hand, in Examples 1 to 3, which are less than the moisture content, the freshness is maintained while suppressing the generation of odor and browning even on the fourth day (after 96 hours) after packaging. In addition, it was found that even on the fifth day (after 120 hours) from the packaging, it is possible to suppress both the off-flavor and browning that consumers who lose commercial value are concerned about.

Further, using Examples 1 to 3 and Comparative Example 1, the number of viable bacteria on the fourth day (96 hours later) and the seventh day (168 hours later) from the cut cabbage packaging was examined. In this case, the packaging was stored at 10 ° C. until the seventh day (after 168 hours). The results are also shown in Table 1.
From this result, in Comparative Example 1 where the moisture content of the cut cabbage is 23%, the moisture content is within the range of less than 23% on both the fourth day (96 hours later) and the seventh day (168 hours later). It was confirmed that the number of viable bacteria was high even when compared with any of the examples. Therefore, Examples 1 to 3 in which the moisture content of the cut cabbage is within a range of less than 23% are superior in terms of suppressing the number of viable bacteria compared to Comparative Example 1 in which the moisture content is 23%. all right. In addition, when the amount of water was 20%, it was examined in the same manner, but the fourth day was 2.8 × 10 ⁶ CFU / g and the seventh day was 3.7 × 10 ⁶ CFU / g, It was also confirmed that the viable cell count was suppressed as compared with 23% of Comparative Example 1.

  According to the present invention, a cabbage to be packaged in a package body containing fruits and vegetables containing cabbage having high economic value (particularly cabbage that has been cut, washed, dehydrated or dried and adjusted to an appropriate amount of water). By controlling the moisture concentration in the inside to an appropriate value, while maintaining the fresh texture of the cabbage, it effectively suppresses the odor and browning of the fruits and vegetables, the number of viable bacteria, and the texture as needed. Therefore, it has high commercial value in practical use, and has high applicability in various fields of industries such as food processing, distribution, and restaurant.

Claims (12)

  A packaged body containing fruits and vegetables containing cabbage in a packaging container comprising a polymer film, wherein the amount of water when the cabbage is stored is less than 23%.   The package according to claim 1, wherein the inside of the packaging container is sealed with nitrogen.   The occurrence of odor of the cabbage can be suppressed for 96 hours or more under the condition of 10 ° C after packaging, and the occurrence of browning of the cabbage can be suppressed for 144 hours or more under the condition of 10 ° C after packaging. Packaging body.   The viable cell count of the cabbage can be suppressed for more than 168 hours under the condition of 10 ° C after packaging, compared to a case where the amount of water at the time of storing the cabbage is 23%. Packaging. 5. The packaging according to claim 1, wherein the polymer film has an oxygen permeability of 500 cc / m ² / day / atm to 30000 cc / day / atm at 20 ° C. and 90% RH. body.   The package according to any one of claims 1 to 5, wherein the packaging container does not have a through hole that can be confirmed by an ink leakage checker.   The package according to any one of claims 1 to 6, wherein the polymer film has a thickness of 15 µm 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.   The package according to any one of claims 1 to 8, wherein the polymer film contains at least one antibacterial agent or is coated with at least one antibacterial agent.   Furthermore, the package for freshness preservation of fruits and vegetables according to any one of claims 1 to 9, further comprising a hygroscopic agent and / or an antibacterial agent.   A method for maintaining freshness of fruits and vegetables under a condition of 2 ° C or higher and 15 ° C or lower, comprising a step of storing fruits and vegetables containing cabbage having a water content of less than 23% in a packaging container comprising a polymer film.   The method for maintaining freshness of fruits and vegetables according to claim 11, further comprising a step of enclosing nitrogen in the packaging container.