Packaging, method for manufacturing packaging

Abstract

Provided are a package that can suitably suppress deterioration of freshness of fruits and vegetables, and a method for manufacturing the package. 【Solution means】The package is a package including a film sealed so as to form an internal space for accommodating fruits and vegetables, wherein the film is a biaxially stretched polypropylene-based resin film having gas permeability, and the oxygen permeability is 1200 cm 3 / (m 2 ·24h·atm) or more to 3800 cm 3 / (m 2 ·24h·atm) or less, and the carbon dioxide permeability is 4200 cm 3 / (m 2 ·24h·atm) or more to 11000 cm 3 / (m 2 ·24h·atm) or less, and the initial gas concentration in the internal space has an oxygen concentration exceeding 20%.

Description

[Technical Field]

[0001] This invention relates to packaging and a method for manufacturing packaging. [Background technology]

[0002] Patent Document 1 discloses a packaging material for containing fresh produce. When this packaging material is stored for 340 hours under predetermined conditions with fresh produce inside, the oxygen concentration inside the packaging material is within the range of 10% to 18%. Because the growth of bacteria attached to the fresh produce is suppressed, the freshness of the produce does not deteriorate easily. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-114748 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The inventors of the present invention have found that the gas permeability of the packaging and the initial gas concentration inside the packaging are important for effectively suppressing the deterioration of fresh produce.

[0005] The present invention aims to provide a packaging material that can effectively suppress the deterioration of fresh produce, and a method for manufacturing the packaging material. [Means for solving the problem]

[0006] A packaging according to a first aspect of the present invention is a packaging comprising a film that is sealed to form an internal space for containing fresh produce, wherein the film is a gas-permeable biaxially oriented polypropylene resin film with an oxygen permeability of 1200 cm². 3 / (m 2 ·24h · atm) or more ~3800cm 3 / (m 2(24h·atm) or less, with a carbon dioxide transmission rate of 4200 cm³. 3 / (m 2 ·24h・atm) or more~11000cm 3 / (m 2 The initial gas concentration in the internal space is within the range of (24h·atm) or less, and the oxygen concentration is greater than 20%.

[0007] The inventors of the present invention have found that when the gas permeability of the film constituting the packaging body falls within the above range, and the initial gas concentration in the internal space of the packaging body is greater than 20% oxygen concentration, the deterioration of fresh produce can be effectively suppressed.

[0008] A packaging according to a second aspect of the present invention is a packaging according to a first aspect, wherein the initial gas concentration in the internal space is greater than 0% and less than or equal to 15% of the carbon dioxide concentration.

[0009] Because the above-mentioned packaging contains carbon dioxide in the gas filling the internal space, the deterioration of fresh produce can be more effectively suppressed.

[0010] A packaging according to a third aspect of the present invention is a packaging according to the first or second aspect, wherein the initial gas concentration in the internal space is a nitrogen concentration of 35% or more and 78% or less.

[0011] Because the above-mentioned packaging contains nitrogen in the gas filling the internal space, the deterioration of fresh produce can be more effectively suppressed.

[0012] The method for manufacturing a package according to the fourth aspect of the present invention includes a sealing step of sealing a film so as to form an internal space for accommodating fresh produce and an opening for accommodating the fresh produce in the internal space, an accommodating step of accommodating the fresh produce in the internal space, which is carried out after the sealing step, a gas filling step of filling the internal space with gas, which is carried out after the accommodating step, and a sealing step of sealing the film so that the opening is closed, which is carried out after the gas filling step. The film is a biaxially stretched polypropylene-based resin film having gas permeability, and the oxygen permeability is 1,200 cm 3 / (m 2 ·24 h·atm) or more and up to 3,800 cm 3 / (m 2 ·24 h·atm), and the carbon dioxide permeability is 4,200 cm 3 / (m 2 ·24 h·atm) or more and up to 11,000 cm 3 / (m 2 ·24 h·atm). The concentration of the gas filled in the internal space in the gas filling step is such that the oxygen concentration is more than 20%.

[0013] According to the above manufacturing method of the package, the gas permeability of the film constituting the package is within the above range, and a package having an initial gas concentration in the internal space of the package with an oxygen concentration of more than 20% is manufactured. Therefore, the same effects as those of the package according to the first aspect can be obtained.

Advantages of the Invention

[0014] According to the package and the method for manufacturing the package of the present invention, it is possible to suitably suppress a decrease in the freshness of fresh produce.

Brief Description of the Drawings

[0015] [Figure 1] Rear view of the package of the embodiment. [Figure 2] Cross-sectional view showing an example of the layer structure of the film of FIG. 1. [Figure 3] Flowchart showing an example of the method for manufacturing the package of FIG. 1. [Figure 4] A table showing the specifications of the packaging used in the example, the results of sensory evaluation, and the results of the evaluation of the total viable cell count. [Figure 5] A table showing the specifications of the comparative example packaging, the results of sensory evaluation, and the results of the evaluation of the total bacterial count. [Modes for carrying out the invention]

[0016] Hereinafter, with reference to the drawings, a package according to one embodiment of the present invention and a method for manufacturing the package will be described.

[0017] <1. Packaging composition> Figure 1 is a rear view of the packaging 10. The packaging 10 is configured to suitably suppress the deterioration of fresh produce 100. The fresh produce 100 is, for example, cut vegetables such as cabbage, lettuce, or carrots, or vegetables such as green onions, bean sprouts, spinach, broccoli, or bell peppers. The packaging 10 is constructed, for example, by folding a single film 20 and heat-sealing the sealing layers 22 (see Figure 2) of the film 20 together so that an internal space 10A for accommodating the fresh produce 100 is formed. The packaging 10 has an upper sealing portion 31, a lower sealing portion 32, and a gusset sealing portion 33. The upper sealing portion 31 is the portion where the upper end of the film 20 is sealed so that an opening 10X for accommodating the fresh produce 100 in the internal space 10A is closed. The lower sealing portion 32 is the portion where the lower end of the film 20 is sealed. The mortise seal portion 33 is the part where a pair of sides of the film 20 are sealed.

[0018] <2. Film composition> <2-1. Overall structure of the film> Figure 2 is a cross-sectional view showing an example of the layer structure of the film 20. The film 20 is a gas-permeable biaxially oriented polypropylene resin film. The film 20 includes a base layer 21 and a sealing layer 22. Regarding the materials constituting the base layer 21 and the sealing layer 22, and the specifications regarding the content of these materials, for example, the matters described in Japanese Patent Application Publication No. 2021-49657 can be applied, so a detailed explanation is omitted. The thickness of the film 20 can be arbitrarily selected. From the viewpoint of using the film 20 in the manufacture of the packaging 10, the thickness of the film 20 is preferably in the range of 10 μm to 50 μm.

[0019] <2-2. Composition of the base layer> The base layer 21 is the outermost layer in the packaging 10, in other words, the layer facing the external space. The base layer 21 is directly laminated with the seal layer 22. The base layer 21 may also be indirectly laminated with the seal layer 22 via, for example, an arbitrary intermediate layer. The thickness of the base layer 21 is arbitrarily selectable. From the viewpoint of using the film 20 in the manufacture of the packaging 10, the thickness of the base layer 21 is preferably in the range of 2 μm to 49 μm.

[0020] The materials constituting the base layer 21 include a polypropylene resin and a gas-permeable resin. Examples of polypropylene resins include polypropylene homopolymers (homopropylene polymers) or crystalline polypropylene resins. Crystalline polypropylene resins are preferred for the materials constituting the base layer 21. The gas-permeable resin is a resin that, when added to the raw materials to form the base layer 21, can form a film 20 that has increased permeability of gases such as oxygen, carbon dioxide, and odors compared to when it is not added to the raw materials. As the gas-permeable resin in the base layer 21, vinyl aromatic hydrocarbon resins are preferred, and styrene resins or hydrogenated styrene elastomers are more preferred. In particular, from the viewpoint of transparency (haze) when made into a film, styrene-ethylene-butylene-styrene block copolymers (SEBS) are preferred. Furthermore, the polypropylene resin used as the material constituting the base layer 21 may be biomass-derived. Known biomass-derived polypropylene resins can be used without limitation. Examples of biomass-derived polypropylene resins include biopolypropylene, which is obtained by synthesizing propylene using naphtha obtained from waste oils such as vegetable oils, and then polymerizing its monomers. Other examples of biomass-derived polypropylene resins include biopolypropylene, which is obtained by obtaining bioethanol from biomass raw materials, and then further obtaining biopropylene from bioethylene, and biomass polypropylene, which is obtained by producing bioisopropanol through fermentation of biomass raw materials and then dehydrating it. However, biomass-derived polypropylene resins are not limited to these examples.

[0021] <2-3. Composition of the sealing layer> The sealing layer 22 is the innermost layer in the packaging 10, in other words, the layer facing the internal space 10A that contains the fruits and vegetables 100. The thickness of the sealing layer 22 can be arbitrarily selected. From the viewpoint that the film 20 is used in the manufacture of the packaging 10, the thickness of the sealing layer 22 is preferably in the range of 1 μm to 8 μm. The material constituting the sealing layer 22 includes a propylene-based random copolymer and a gas-permeable resin. The propylene-based random copolymer is a copolymer of propylene and other α-olefins, and is not particularly limited as long as it is processed to form the sealing layer 22 and has sealing properties such that the sealing layers 22 fuse together when heat is applied to the sealing layer 22. Examples of α-olefins other than propylene include α-olefins other than propylene having 2 to 20 carbon atoms. Specifically, examples include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 3-methyl-1-butene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, cyclopentene, cycloheptene, norbornene, 5-ethyl-2-norbornene, tetracyclododecene, and 2-ethyl-1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene. Furthermore, the propylene-based random copolymer used as the material constituting the seal layer 22 may be derived from biomass. Known propylene-based random copolymers derived from biomass can be used without limitation. Examples of biomass-derived propylene-based random copolymers include biopolypropylene, which is obtained by synthesizing propylene using naphtha obtained from waste oils such as vegetable oils, and then polymerizing its monomers. Other examples of biomass-derived propylene-based random copolymers include biopolypropylene, which is obtained by obtaining bioethanol from biomass raw materials, and then further obtaining biopropylene from bioethylene, and biomass polypropylene, which is obtained by producing bioisopropanol through fermentation of biomass raw materials and then dehydrating it. However, biomass-derived propylene-based random copolymers are not limited to these examples.

[0022] The definition of gas-permeable resin in the seal layer 22 is the same as the definition described for the base layer 21. Examples of gas-permeable resins included in the material constituting the seal layer 22 include polyethylene resins, vinyl aromatic hydrocarbon resins, silicone rubber, natural rubber, polyurethane, polybutadiene, or butadiene rubber. Among these, polyethylene resins are preferred from the viewpoint of gas permeability and heat sealability.

[0023] In the manufacturing of the packaging 10, after the fruits and vegetables 100 are placed in the internal space 10A, the internal space 10A is filled with a mixed gas containing oxygen in order to suppress the deterioration of the freshness of the fruits and vegetables 100. The inventors of the present invention have found that by appropriately setting the gas permeability of the packaging 10 and the initial gas concentration inside the packaging 10, the oxygen concentration inside the packaging 10 falls within a desirable range for suppressing bacterial growth, thereby effectively suppressing the deterioration of the freshness of the fruits and vegetables 100.

[0024] From the viewpoint of effectively suppressing the deterioration of fresh produce 100, the oxygen permeability of the film 20 is 1200 cm². 3 / (m 2 ·24h · atm) or more ~3800cm 3 / (m 2 It falls within the range of (24h·atm) or less. Also, from the perspective of suppressing the total number of viable bacteria, the upper limit of the oxygen permeability of film 20 is 2800 cm². 3 / (m 2 It is more preferable that the temperature is 24 hours (atm) or less, and 2400 cm². 3 / (m 2 It is even more preferable that the carbon dioxide transmission rate of film 20 is 4200 cm⁻¹ or less (24h·atm). From the same viewpoint, the carbon dioxide transmission rate of film 20 is 4200 cm⁻¹. 3 / (m 2 ·24h・atm) or more~11000cm 3 / (m 2 It falls within the range of (24h·atm) or less. Furthermore, the upper limit of carbon dioxide transmission for film 20 is 8000 cm³. 3 / (m 2 It is more preferable that the temperature is 24 hours (atm) or less, and 7000 cm².3 / (m 2 It is even more preferable that the operating hours (24 hours / atm) are 24 hours or less.

[0025] The mixed gas preferably contains at least one of carbon dioxide and nitrogen in addition to oxygen. In this embodiment, the mixed gas contains oxygen, carbon dioxide, and nitrogen. The inventors of this application have found that the deterioration of the freshness of fruits and vegetables 100 can be suppressed by adjusting the initial concentration of the mixed gas filled into the internal space 10A, particularly the oxygen concentration contained in the mixed gas. The initial concentration of the mixed gas is the concentration of the mixed gas filled into the internal space 10A, or in other words, the concentration of the mixed gas present in the internal space 10A immediately after the internal space 10A is filled with the mixed gas and sealed. In this embodiment, the initial concentration of the mixed gas has an oxygen concentration of more than 20%. The initial concentration of the mixed gas preferably has a carbon dioxide concentration in the range of more than 0% to 15% or less. The initial concentration of the mixed gas preferably has a nitrogen concentration in the range of 35% or more to 78% or less.

[0026] <3. Method for manufacturing packaging> Referring to Figure 3, an example of a method for manufacturing the packaging 10 will be explained. The manufacturing method for the packaging 10 includes a sealing step, a packaging step, a gas filling step, and a sealing step. For example, a vertical pillow packaging machine can be used to manufacture the packaging 10.

[0027] In the sealing process of step S11, the film 20 is heat-sealed so that the lower sealing portion 32 and the gusset sealing portion 33 are formed. The upper sealing portion 31 is not formed in the sealing process. Once the sealing process is complete, an intermediate package 10 is manufactured, which has an internal space 10A for containing the produce 100 and an opening 10X for containing the produce 100 in the internal space 10A.

[0028] The containment process in step S12 is performed after the sealing process. In the containment process, the produce 100 is placed in the internal space 10A through the opening 10X.

[0029] The gas filling process in step S13 is performed after the containment process. In the gas filling process, the mixed gas is filled into the internal space 10A through the opening 10X. Note that the gas filling process may be performed before the containment process, and the containment process and the gas filling process may be performed simultaneously.

[0030] The sealing step S14 is performed after the gas filling step. In the sealing step, the film 20 is heat-sealed so that the opening 10X is closed.

[0031] <4. Function and Effects of Packaging> In the packaging 10, the oxygen permeability and carbon dioxide permeability of the film 20 are set as described above, and the initial oxygen concentration of the internal space 10A is more than 20%, so the environment inside the internal space 10A is one in which bacteria are less likely to grow. Therefore, the deterioration of the freshness of the produce 100 can be effectively suppressed.

[0032] <5. Examples> <5-1. Overview> The inventors of the present invention manufactured the packaging of the Examples and the packaging of the Comparative Examples, and conducted sensory evaluations and evaluations regarding the total viable cell count. For the convenience of explanation, in the following description, elements constituting the packaging of the Examples and Comparative Examples that are the same as those in the Examples will be denoted by the same reference numerals as in the Examples.

[0033] Figure 4 shows the specifications, sensory evaluation results, and total bacterial count evaluation results for the packaging 10 of Examples 1-8. Figure 5 shows the specifications, sensory evaluation results, and total bacterial count evaluation results for the packaging 10 of Comparative Examples 1-4. The fruits and vegetables 100 contained in the packaging 10 of Examples 1-8 and Comparative Examples 1-4 are cut cabbage. The weight of the cut cabbage is 130 g. The outer dimensions of the packaging 10 of Examples 1-8 and Comparative Examples 1-4 are 240 mm in length and 195 mm in width, and the size of the internal space 10A is substantially the same as the outer dimensions. The seal width of the upper seal portion 31, lower seal portion 32, and gusset seal portion 33 of the packaging 10 of Examples 1-8 and Comparative Examples 1-4 is 10 mm. The packaging 10 of Examples 1-8 and Comparative Examples 1-4 were stored at 10°C for 120 hours, after which sensory evaluation and evaluation of the total bacterial count were performed. Note that the post-processing shown in Figures 4 and 5 refers to the formation of minute through-holes in the film 20 to increase its gas permeability. Only in Comparative Example 3 were through-holes formed in the film 20.

[0034] <5-2. Method for measuring transmittance> The permeability shown in Figures 4 and 5 was measured by cutting the film 20 constituting the packaging 10 of Examples 1-8 and Comparative Examples 1-4 into 10 cm squares to prepare the measurement samples. The oxygen and carbon dioxide permeability of each measurement sample was measured using the differential pressure method with a differential pressure type gas permeability measuring device (manufactured by Toyo Seiki Seisakusho Co., Ltd.) under the conditions of a set pressure of 101.3 kPa and a set temperature of 23.0 °C.

[0035] <5-3. Method for measuring transmittance> Immediately after manufacturing the packaging 10 for Examples 1-8 and Comparative Examples 1-4, the oxygen and carbon dioxide concentrations in the internal space 10A (internal dimensions: 240 mm vertically x 195 mm horizontally) of the packaging 10 were measured using Check Point 3 (manufactured by mocon).

[0036] <5-4. Method for producing mixed gases> Cut cabbage was placed in the internal space 10A of the intermediate part of the packaging 10. Nitrogen, oxygen, and carbon dioxide were prepared in separate cylinders, and gas tubes, an oxygen concentration meter, and the sensor parts of the carbon dioxide concentration meter were inserted into the opening 10X. The gas flow rates of each cylinder were adjusted while measuring the concentration of each gas. Once the desired gas ratio was achieved, the gas was allowed to flow at that rate for a while to form the upper seal portion 31, thereby sealing the packaging 10.

[0037] <5-5. Sensory Evaluation> Sensory evaluation was performed on each of the 10 packaging samples from Examples 1-8 and Comparative Examples 1-4, with n=5 in each test group.

[0038] <5-5-1. Taste Evaluation> The products will be tasted and scored according to the following criteria. A score of 3 or less indicates a decrease in product value. 5 points: Juicy and with a noticeable sweetness from the fruit and vegetables. 4 points: It's juicy, but has a slight bitterness. 3 points: It lacks freshness. It's bitter. Points 2: I can taste bitterness and a slight astringency. 1 point: It has a strong bitter and astringent taste.

[0039] <5-5-2. Odor Evaluation> The odor is smelled and scored according to the following criteria. A score of 3 or less indicates a decrease in product value. 5 points: There is absolutely no smell of decay. 4 points: Upon opening package 10, there was a faint smell of decay. 3. It has a rotten smell, but the smell disappears if you leave the packaging open for 30 minutes. Points 2: It has a strong rotten smell. If you open the packaging and leave it for an hour, the rotten smell will lessen. 1. Even after opening the package 10 and leaving it for an hour, a strong, pungent, putrid odor persists.

[0040] <5-5-3. Color Evaluation> Observe the color and score it according to the following criteria. A score of 3 or less indicates a decrease in product value. 5 points: Overall, it's vibrant and crisp. 4 points: The vibrant green color is slightly diminished, but it still has a crisp appearance. 3 points: The vibrant green color is diminished, and the brown areas are more noticeable. Points 2: The brown parts have increased, and it's almost completely lost its crispness. 1 point: The whole thing is brown and completely lacks crispness.

[0041] <5-6. Results of sensory evaluation> As shown in Figure 4, the packaging 10 of Examples 1 to 8 was confirmed to receive high ratings in sensory evaluation. This is thought to be because the oxygen permeability, carbon dioxide permeability, and initial gas concentration of the film 20 constituting the packaging 10 of Examples 1 to 8 fall within the range of the embodiments. Furthermore, even when the oxygen permeability is relatively low, as in Examples 6 to 9, high ratings were confirmed in sensory evaluation because the oxygen concentration of the initial gas concentration is over 20%.

[0042] As shown in Figure 5, the packaging 10 of Comparative Examples 1 to 4 were found to have received low ratings in sensory evaluation. In Comparative Examples 1 and 2, the initial gas concentration of the packaging 10 was 20% or less, which is thought to be due to oxygen deficiency in the internal space 10A and subsequent bacterial growth. In Comparative Example 3, the initial gas concentration of the packaging 10 was over 20%, but the oxygen permeability of the film 20 was too high, which is thought to have caused excessive oxygen in the internal space 10A and subsequent bacterial growth. In Comparative Example 4, the initial gas concentration of the packaging 10 was over 20%, but the oxygen permeability of the film 20 was too low, which is thought to have caused oxygen deficiency in the internal space 10A and subsequent bacterial growth.

[0043] <5-7. Evaluation of total viable cell count> For the evaluation of total viable cell count, 10 g of the sample cut cabbage is homogenized in 90 cc of phosphate buffer. Next, 1 mL of the resulting 10-fold diluted solution is taken and diluted with 9 mL of phosphate buffer to obtain a further 10-fold diluted sample solution. Then, the diluted solution, diluted to an appropriate dilution ratio, is incubated on 3M Petrifilm medium at 35°C for 48 hours, and the total viable cell count (CFU / g) is counted.

[0044] As shown in Figure 4, the difference in the total number of viable bacteria from the first day of the packaging 10 of Examples 1 to 8 was 10 3 It was confirmed that the increase in the total number of viable bacteria was effectively suppressed, to a level lower than CFU / g. This is thought to be because the oxygen permeability, carbon dioxide permeability, and initial gas concentration of the film 20 constituting the packaging 10 in Examples 1 to 8 fall within the range of the embodiments.

[0045] As shown in Figure 5, the difference in the total number of viable bacteria from the first day in the packaging 10 of Examples 1 to 8 is 10 3 It was confirmed that the total viable cell count was higher than CFU / g, in other words, significantly increased. This is thought to be for the same reasons as those discussed in the sensory evaluation results.

[0046] <6. Variation> The embodiments described above are illustrative examples of possible forms of the packaging and manufacturing method of the present invention, and are not intended to limit their forms. The packaging and manufacturing method of the present invention may take forms different from those illustrated in the embodiments. One example is a form in which some of the configurations of the embodiments are replaced, modified, or omitted, or a form in which new configurations are added to the embodiments. Several examples of modifications of the embodiments are shown below.

[0047] <6-1> In the above embodiment, the mixed gas filling the internal space 10A contained oxygen, carbon dioxide, and nitrogen, but the composition of the mixed gas is not limited thereto. For example, the mixed gas may not contain at least one of carbon dioxide and nitrogen.

[0048] <6-2> In the above embodiment, the package 10 was manufactured from a single film 20 using a vertical pillow packaging machine. However, the package 10 may also be manufactured by heat sealing two or more films 20, for example.

[0049] <6-3> In the above embodiment, the sealing layers 22 of the film 20 were joined together by heat sealing, but the means for sealing the sealing layers 22 of the film 20 together can be arbitrarily changed. For example, the sealing layers 22 of the film 20 together may be sealed by impulse sealing, high-frequency sealing, or ultrasonic sealing. [Explanation of Symbols]

[0050] 10: Packaging 10A: Internal space 10X:Aperture 20: Film

Claims

1. A package comprising a film that is sealed to form an internal space for containing fruits and vegetables, The aforementioned film is a biaxially oriented polypropylene resin film that includes a sealing layer and is gas permeable. Oxygen permeability is 1200 cm 3 / (m 2 ・24h・ATM) or more ~3800cm 3 / (m 2 (24h・atm) included in the following range, The carbon dioxide transmission rate is 4200 cm³. 3 / (m 2 ・24h・ATM) or more ~11000cm 3 / (m 2 (24h・atm) included in the following range, The initial gas concentration in the aforementioned internal space is such that the oxygen concentration is over 20%. packaging.

2. The initial gas concentration in the aforementioned internal space is a nitrogen concentration of 35% or more and 78% or less. The packaging according to claim 1.

3. The initial gas concentration in the aforementioned internal space is a nitrogen concentration of 40% or more and 68% or less. The packaging according to claim 2.

4. The initial gas concentration in the aforementioned internal space is a nitrogen concentration of 45% or more and 60% or less. The packaging according to claim 2.

5. The thickness of the sealing layer is 1 to 8 μm. The packaging according to claim 1.

6. A sealing step of sealing a film such that an internal space for containing fruits and vegetables is formed, and an opening for containing the fruits and vegetables is formed in the internal space, A storage step is performed after the sealing step, in which the fruits and vegetables are placed into the internal space through the opening, The process includes a gas filling step performed after the containment step, in which gas is filled into the internal space, and a sealing step performed after the gas filling step, in which the film is sealed so that the opening is closed. The aforementioned film is a biaxially oriented polypropylene resin film that includes a sealing layer and is gas permeable. The oxygen permeability is within the range of 1200 cm 3 / (m 2 ·24 h·atm) or more to 3800 cm 3 / (m 2 ·24 h·atm) or less, and The carbon dioxide transmission rate is 4200 cm³. 3 / (m 2 ・24h・ATM) or more ~11000cm 3 / (m 2 (24h・atm) included in the following range, In the gas filling process, the concentration of the gas filled into the internal space is such that the oxygen concentration is greater than 20%. A method for manufacturing packaging.

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