Fruit and vegetables-storing package, and freshness keeping method of fruit and vegetables

Abstract

To provide a fruit and vegetables-storing package capable of keeping freshness of fruit and vegetables.SOLUTION: In a fruit and vegetables-storing package, which is formed by packaging fruit and vegetables with a packaging bag constituted of a synthetic resin film, the rate of change of an oxygen concentration {(oxygen concentration after treatment) / (oxygen concentration before treatment)×100}(%) in the packaging bag before and after performing a following treatment is 0.5% or higher and 400% or lower, and an oxygen permeation amount at 23°C and 60%RH is 2 cc / m2-day-atm or more and 50,000 cc / m2-day-atm or less; the treatment: the packaging bag is held for 3 days under a condition of 20°C and 50%RH.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a package containing fruits and vegetables and a method for preserving the freshness of fruits and vegetables. [Background technology]

[0002] A conventional method for preserving the freshness of harvested fruits and vegetables involves appropriately suppressing the respiration of the fruits and vegetables to maintain their freshness. Such packaging bags used to preserve the freshness of fruits and vegetables are known as modified atmosphere (MA) packaging.

[0003] For example, Patent Document 1 discloses a method for preserving processed fresh vegetables, including lettuce, using a packaging bag that blocks air from entering or leaving the bag, and filling the bag with gas concentrations of 5% to 10% oxygen, 15 to 35% carbon dioxide, and the remainder nitrogen gas. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-80 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology described in Patent Document 1 blocks the flow of air in and out of the storage area, and therefore has problems such as a decrease in oxygen concentration and an excessive increase in carbon dioxide concentration due to the respiration of fresh produce such as lettuce during storage, which causes gas damage and the generation of unpleasant odors. [Means for solving the problem]

[0006] In the course of intensive research to solve the problems of the prior art, the inventor first found that simply specifying the oxygen transmission rate is not enough as a condition that a package should have. Then, as a result of further research assuming the use of a packaging bag with a predetermined oxygen transmission rate, the inventor discovered for the first time that controlling the rate of change in oxygen concentration when a package containing fruit or vegetables is subjected to a predetermined treatment is an effective design guideline for improving the freshness retention of the fruit or vegetables, and thus completed the present invention.

[0007] The present invention provides a package containing fruits and vegetables, which is made by packaging fruits and vegetables in a packaging bag made of a synthetic resin film, The rate of change in oxygen concentration within the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment) x 100] (%) is 0.5% or more and 400% or less, Oxygen permeability at 23℃ and 60%RH is 2cc / m 2 ·day · atm or more, 50000cc / m 2 To provide a package containing fruits and vegetables that is less than 1000mg / day atm. Treatment: Store the package under conditions of 20°C and 50% RH for 3 days.

[0008] The present invention also provides a method for preserving the freshness of fruits and vegetables by packaging the fruits and vegetables in a packaging bag made of a synthetic resin film, comprising: The rate of change in oxygen concentration within the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment) x 100] (%) is 0.5% or more and 400% or less, Oxygen permeability at 23℃ and 60%RH is 2cc / m 2 ·day · atm or more, 50000cc / m 2 To provide a method for preserving the freshness of fruits and vegetables by packaging them so that they are kept at or below 10 ... Treatment: Store the package under conditions of 20°C and 50% RH for 3 days. [Effects of the Invention]

[0009] According to the present invention, a package containing fruits and vegetables can be provided that can maintain the freshness of the fruits and vegetables for a longer period of time. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Packaging bag> Hereinafter, embodiments of the present invention will be described in detail.

[0011] The packaging bag in this embodiment is used to package fruits and vegetables inside. The fruits and vegetables are not particularly limited, but examples thereof include: Chinese radish, spinach, komatsuna, mizuna, mibuna, asparagus, swiss cabbage, lettuce, thyme, sage, parsley, Italian parsley, rosemary, oregano, lemon balm, chives, lavender, salad burnet, lamb's ear, rocket, dandelion, nasturtium, basil, arugula, watercress, mulukhiyah, celery, kale, green onion, cabbage, Chinese cabbage, garland chrysanthemum, and salad. These include lettuce, lettuce, butterbur, turnip, bok choy, mitsuba, parsley, Brussels sprouts, broccoli, cauliflower, myoga, daikon radish, carrot, burdock, radish, turnip, sweet potato, potato, Chinese yam, taro, jinenjo, Japanese yam, bell pepper, paprika, shishito pepper, cucumber, eggplant, tomato, cherry tomato, pumpkin, bitter melon, okra, sweet corn, edamame, snow peas, green beans, broad beans, and fungi. Fruits such as citrus fruits, apples, pears, grapes, blueberries, persimmons, and strawberries, as well as cut flowers, are also effective. Cut vegetables and fruits are also effective. Among these, cut vegetables are preferred from the viewpoint of enabling effective storage.

[0012] The oxygen permeability of the packaging bag at 23°C and 60% RH is preferably 2 cc / m from the viewpoint of maintaining the respiration of fruits and vegetables and preserving their freshness. 2 ·day·atm or more, and more preferably 5cc / m 2 ·day·atm or more, and more preferably 300cc / m 2 ·day·atm or more. On the other hand, the oxygen permeability of the packaging bag at 23°C and 60% RH is preferably 50,000 cc / m from the viewpoint of maintaining the quality and freshness of fruits and vegetables. 2 ·day·atm or less, and more preferably 10000cc / m 2 ·day·atm or less, and more preferably 7500cc / m 2 ·day·atm or less.

[0013] The oxygen permeation rate can be calculated, for example, by measuring the oxygen concentration inside the packaging bag immediately after filling it with nitrogen and after leaving it for a certain period of time after filling it with nitrogen, and then calculating the oxygen concentration gradient.

[0014] In addition, in this embodiment, the oxygen permeability of the packaging bag can be adjusted by controlling the selection of the material of the synthetic resin film described below, the manufacturing method of the synthetic resin film, the layer structure of the synthetic resin film, the presence or absence of through holes, and the average diameter and number of through holes, etc.

[0015] The water vapor permeability of the packaging bag at 40°C is set at 2g / m2, taking into consideration the release of water vapor due to respiration of fruits and vegetables. 2 4g / m 2 ·day·atm or more, and more preferably 6g / m 2 ·day·atm or more. On the other hand, the water vapor transmission rate of the packaging bag at 40°C is set at 10g / m2 in order to suppress the respiration of fruits and vegetables. 2 ·day·atm or less, preferably 8g / m 2 ·day·atm or less, and more preferably 7g / m 2 ·day·atm or less.

[0016] The water vapor transmission rate can be measured by a method in accordance with JIS Z0208 (cup method).

[0017] In this embodiment, the water vapor permeability of the packaging bag can be adjusted by controlling the selection of the material of the synthetic resin film described below, the manufacturing method of the synthetic resin film, the layer structure of the synthetic resin film, the presence or absence of through holes, and the average diameter and number of the through holes.

[0018] The packaging bag of this embodiment can further enhance the freshness-preserving effect by further satisfying the following requirements.

[0019] The packaging bag may have through holes formed therein, which allows the water vapor transmission rate and oxygen transmission rate to be stably adjusted, thereby effectively preserving the freshness of fruits and vegetables.

[0020] The planar shape of the through-hole may be, for example, a circle, a polygon, or a slit. The circle is not limited to a perfect circle and includes an approximate circle. In addition to a circle, the through-hole may be a semicircle or a crescent shape. The polygon may be any shape surrounded by three or more line segments, such as a triangle, a rectangle, or a pentagon. The slit is a cut or narrow gap that penetrates the synthetic resin film that constitutes the packaging bag, and may be a straight line, a curve, an L-shape, an X-shape, or the like, and its length is not particularly limited.

[0021] The average diameter of the through-holes is preferably 30 μm to 1100 μm, and more preferably 50 μm to 500 μm. By making the diameter equal to or greater than the above lower limit, the water vapor transmission rate and oxygen transmission rate are improved, and mold growth is more easily suppressed. On the other hand, by making the diameter equal to or less than the above upper limit, the intrusion of foreign matter can be prevented and wilting and stem withering of fruits and vegetables can be suppressed. The average diameter of the through holes is calculated from the open area of ​​the through holes, assuming that the through holes are perfect circles.

[0022] The number of through holes relative to the internal surface area of ​​the packaging bag is 1 / m 2 More than 1500 pieces / m 2 It is preferable that the number of particles is less than 2 / m. 2 More than 1000 pieces / m 2 More preferably, it is 10 pieces / m or less. 2More than 800 pieces / m 2 It is even more preferable that:

[0023] Furthermore, when viewed in cross section of the through-holes, where Sout is the hole area on the outer surface of the packaging bag and Sin is the hole area on the inner surface of the packaging bag, it is preferable that Sout / Sin > 1.1. That is, when the hole area on the outer surface is larger than the hole area on the inner surface, deformation of the holes due to the weight of the fruits and vegetables can be reduced and the gas concentration inside the packaging bag can be more stabilized, making it easier to maintain the freshness of the fruits and vegetables. From the viewpoint of ensuring flow paths for oxygen and water vapor and stabilizing the concentrations, deterioration or spoilage of the fruits and vegetables can be more stably suppressed. In this case, the average diameter of the through holes indicates the diameter of the holes on the inner surface of the packaging bag.

[0024] Furthermore, when the through-hole is viewed in cross section, the side wall of the through-hole preferably has a tapered shape that gradually widens from the inner surface toward the outer surface of the packaging bag. By making the side wall tapered, deformation of the hole is further reduced, and freshness can be maintained more stably.

[0025] The method for forming the through holes is not particularly limited, and any known method can be used, such as a laser processing method, a needle processing method including a hot needle, or a method using a mold such as a roll cutter. The through holes having the above Sout / Sin>1.1 can be formed by laser processing, etc. With laser processing, the diameter of the through holes can be adjusted, for example, by synchronizing the running speed of the synthetic resin film with the frequency of the laser, and the shape of the through holes matches the shape of the laser, so that the shape can be changed from cylindrical to tapered by adjusting the focal length of the laser.

[0026] The above-mentioned through holes may be formed in the synthetic resin film in advance when manufacturing the packaging bag, or may be formed after the synthetic resin film has been formed into a bag shape, or may be formed before or after the synthetic resin film has been formed into a bag shape.

[0027] The inner surface area of ​​the packaging bag in this embodiment can be set appropriately depending on the shape, size, handling, etc. of the fruit or vegetable to be packaged. For example, the inner surface area of ​​the packaging bag per 100 g of fruit or vegetable can be set to 100 cm 2 More than 5000cm 2 It can be less than 300cm 2 More than 700cm 2 The following may also be used.

[0028] Next, the synthetic resin film that constitutes the packaging bag will be described.

[0029] The synthetic resin film is preferably transparent or translucent, more preferably transparent, from the viewpoint of allowing the fruit or vegetable to be visually recognized from the outside. Furthermore, the synthetic resin film may be printed with information for identifying the fruit or vegetable.

[0030] The synthetic resin constituting the synthetic resin film is not particularly limited as long as it can be used for packaging fruits and vegetables, and any known synthetic resin can be used. Examples include various polyethylenes and ethylene copolymers, polypropylene, polyvinyl chloride, polystyrene, acrylic resins, polyester resins such as polyethylene terephthalate and polylactic acid, and polyamide resins such as nylon 6. These may be homopolymers, copolymers of two or more types, or blends containing two or more types of these homopolymers or copolymers. Specific examples of the various polyethylenes and ethylene copolymers include copolymers such as ethylene-vinyl alcohol copolymer, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, metallocene-linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-propylene copolymer, and ethylene-α-olefin copolymer, as well as ionomers. These may contain one or more types, or may be mixed with other resins.

[0031] Among these, from the viewpoint of appropriately controlling the water vapor transmission rate and oxygen transmission rate, polyester resins such as polyethylene, ethylene-vinyl alcohol copolymer, polypropylene, polystyrene, and polylactic acid, and polyamide resins such as nylon are preferred, and ethylene-vinyl alcohol copolymer, polystyrene, polylactic acid, and nylon are more preferred.

[0032] From the viewpoint of cost and physical properties, it is preferable to use a heat-sealable stretched polypropylene film, a low-density polyethylene film, a linear low-density polyethylene film, or a metallocene-catalyzed polyethylene film.

[0033] The molding method for the synthetic resin film is not particularly limited, but may be extrusion, inflation, calendering, etc. When molding the synthetic resin film, additives such as an anti-fogging agent may be kneaded into the film, if necessary, or two or more types of resins may be blended. The synthetic resin film may be stretched or annealed, and may further include a sealant layer. Stretching the synthetic resin film can improve its rigidity, pinhole resistance, water vapor and oxygen barrier properties, and appearance. For example, stretched nylon, stretched polylactic acid, and stretched polystyrene are preferred.

[0034] The synthetic resin film may be used as a single layer or as a multi-layer structure of two or more layers.

[0035] For example, when the fruits and vegetables to be packaged in the packaging bag are heavy, it is preferable to use a multilayer film made by dry lamination, extrusion lamination, or co-extrusion of polyethylene onto a film such as unstretched polypropylene, oriented polypropylene, unstretched nylon, oriented nylon, or oriented polyester.

[0036] The average thickness of the synthetic resin film is preferably 15 μm or more and 400 μm or less, more preferably 20 μm or more and 200 μm or less, and even more preferably 25 μm or more and 100 μm or less. By setting the thickness at or above the lower limit, it becomes easier to control the oxygen transmission rate and water vapor transmission rate to a higher degree, and the strength of the packaging bag can be increased. On the other hand, by setting the thickness at or below the upper limit, the handling of the packaging bag can be improved, appropriate water vapor transmission rate and oxygen transmission rate can be imparted, and production costs can be reduced.

[0037] <Packaging containing fruits and vegetables> The package containing fruit and vegetables in this embodiment is formed by accommodating fruit and vegetables in the packaging bag described above in this embodiment.

[0038] The package containing fruit and vegetables in this embodiment has an oxygen permeability of 2 cc / m at 23°C and 60% RH. 2 ·day · atm or more, 50000cc / m 2 ·day·atm or less, the rate of change in oxygen concentration within the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment) x 100] (%) is between 0.5% and 400%. Treatment: Store the package under conditions of 20°C and 50% RH for 3 days.

[0039] That is, the fruit and vegetable package of this embodiment improves the freshness preservation of fruit and vegetables by satisfying a specific oxygen concentration change rate condition, assuming a predetermined oxygen transmission rate. While the details of why this effect is achieved are unclear, it is speculated as follows: Because the oxygen concentration inside the package significantly affects the freshness preservation of fruit and vegetables, it is important to control the oxygen concentration inside the package within an appropriate range. However, even if the oxygen transmission rate of the packaging bag itself is controlled, the oxygen concentration inside the package changes due to the respiration of the fruit and vegetables during storage. Therefore, the conditions of 20°C and 50% RH are intended to simulate the environment in which fruit and vegetables are packaged, distributed, and stored. By controlling the rate of change of oxygen concentration inside the package stored under these conditions at a level different from that of conventional technology, it is believed that the oxygen concentration inside the package will be more likely to be maintained within an appropriate range. As a result, it is believed that the freshness preservation effect of fruit and vegetables can be improved.

[0040] The oxygen change rate is 0.5% or more and 400% or less, preferably 1% or more and 350% or less, more preferably 2% or more and 300% or less, and further preferably 10% or more and 200% or less. Setting the oxygen concentration change rate above the lower limit indicates that the change in oxygen concentration before and after processing is large, and indicates that the respiration rate of fruits and vegetables during storage has been optimized. This suppresses the growth of bacteria and prevents discoloration, texture, and flavor deterioration due to anaerobic respiration (oxygen deficiency). On the other hand, keeping the oxygen concentration change rate below the upper limit aims to minimize the change in oxygen concentration before and after processing, and indicates that the respiration rate of fruits and vegetables during storage does not deviate too far from the optimal value. This prevents the growth of bacteria and prevents discoloration, texture, and flavor deterioration due to anaerobic respiration (oxygen deficiency).

[0041] The rate of change in oxygen concentration can be controlled by selecting the material of the synthetic resin film, the manufacturing method of the synthetic resin film, the layer structure of the synthetic resin film, the presence or absence of through holes, and adjusting the average diameter and number of the through holes, etc.

[0042] In order to place the fruit or vegetable inside the packaging bag and seal the package, the opening may be heat-sealed or a back-sealing tape, cable ties, rubber bands, caulking, etc. Among these, it is preferable to heat-seal the opening from the viewpoint of enhancing the freshness-preserving effect of the fruit or vegetable.

[0043] Fruits and vegetables that have been washed with water after harvest or that have been wet with rain, snow, or dew can be packaged without draining the water, which improves workability. On the other hand, to maintain freshness, fruits and vegetables can be stored at low temperatures as soon as possible, or moisture adhering to fruits and vegetables can be removed by vacuum pre-cooling or other methods to remove the effects of moisture on fruits and vegetables as soon as possible.

[0044] Furthermore, the weight retention rate of the package containing fruits and vegetables in this embodiment is preferably 95% or more, more preferably 97% or more, and even more preferably 98% or more. By achieving such a value, the freshness of the fruits and vegetables can be maintained more stably.

[0045] <How to keep fruits and vegetables fresh> The packaging method for fruits and vegetables in this embodiment is a method for preserving the freshness of fruits and vegetables by packaging the fruits and vegetables in a packaging bag made of a synthetic resin film, The present invention also provides a method for preserving the freshness of fruits and vegetables by packaging the fruits and vegetables in a packaging bag made of a synthetic resin film, comprising: The rate of change in oxygen concentration within the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment) x 100] (%) is 0.5% or more and 400% or less, Oxygen permeability (cc / m) at 23°C and 60% RH 2 This is to package fruits and vegetables so that the humidity (H2O / day / atm) is between 2 and 50,000. Treatment: Store the package under conditions of 20°C and 50% RH for 3 days. This effectively preserves the freshness of fruits and vegetables.

[0046] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations can also be adopted. [Example]

[0047] Next, the present invention will be described in detail with reference to examples, but the content of the present invention is not limited to the examples.

[0048] Example 1 First, polypropylene resin (product number WFW5T, manufactured by Japan Polypropylene Corporation) was prepared as a synthetic resin material. Next, the melt obtained by melting the film raw material was extruded through a T-die at a temperature of 230°C. The extruded melt was then stretched 5 times vertically and 9 times horizontally to obtain a biaxially stretched polypropylene film (synthetic resin film) with a final thickness of 25 μm. Two sheets of the synthetic resin film were stacked together with the inner film facing inward, and heat-sealed on three sides using an impulse sealer (Fuji Impulse, FI-400Y-10PK) to form a 10 mm wide heat-sealed area at 160°C for 1 second to produce a packaging bag. The resulting packaging bag had an inner size of 200 mm x 160 mm. Next, vegetables and fruits (150 g of cut cabbage) were placed in the resulting packaging bag, and the packaging bag was sealed to prepare a package containing vegetables and fruits.

[0049] Example 2 Inner surface area of ​​packaging bag 1m 2 A package containing fruit and vegetables was produced in the same manner as in Example 1, except that 30 micropores with an average pore diameter of 80 μm were punched per package.

[0050] Example 3 A biaxially oriented nylon film (manufactured by Unitika Ltd., product name "Emblem ONBC", thickness 25 μm) was used as the synthetic resin film, and the inner surface area of ​​the package was 1 m 2 A package containing fruit and vegetables was produced in the same manner as in Example 1, except that fine holes with an average hole diameter of 120 μm were punched so that there were 60 holes per package.

[0051] (Comparative Example 1) Inner surface area of ​​the package: 1m 2 A package containing fruits and vegetables was produced in the same manner as in Example 1, except that fine holes with an average hole diameter of 2000 μm were punched so that there were 2000 holes per package.

[0052] (Comparative Example 2) A package containing fruit and vegetables was produced in the same manner as in Example 3, except that no holes were made.

[0053] The following measurements were carried out on each of the resulting packages containing fruits and vegetables. The results are shown in Table 1.

[0054] <Measurement> Measurement of gas concentration in fruit and vegetable packaging: Fresh produce (150g of cut cabbage) was packed into a packaging bag (inner dimensions of the bag: 200mm x 160mm) and the gas inside the package was immediately measured using Check Point O2 / CO2 manufactured by MOCON Europe.

[0055] Rate of change in oxygen concentration (oxygen change rate): The package was stored for 3 days under conditions of 20°C and 50% RH, and the oxygen concentration inside the package was measured before and after treatment, and calculated using the formula [(oxygen concentration after treatment) / (oxygen concentration before treatment) x 100] (%).

[0056] -Water vapor permeability of packaging bag at 40℃ (g / m 2 ·day·atm) measurement Measurements were taken in the same manner as in the moisture-proof packaging material water vapor transmission rate test method (cup method) (JIS Z0208), except that the temperature was set at 2°C and humidity at 60%.

[0057] Oxygen permeability of packaging bag at 23℃ and 60%RH (cc / m 2 ·day·atm) measurement (1) Nitrogen gas filling After sealing the bag with a heat seal or the like, the bag was degassed using an aspirator or the like. Degassing was continued until both sides of the bag were stuck together. Next, the bag was filled with nitrogen gas (purity 99.9% or higher) using a white hard syringe. The amount of nitrogen gas injected was adjusted to the bag size, and as much as possible was injected so that the injected nitrogen gas did not put tension on the film constituting the bag and left it slightly loose, and the amount was measured using the scale on the white hard syringe. The degassing and injection of nitrogen gas was carried out, for example, by piercing the bag with a syringe needle. When inserting the syringe needle, double-sided tape was attached to the film constituting the bag, and then adhesive tape made of polypropylene film (hereinafter referred to as "PP tape") was attached on top of this. After the syringe needle was removed, the pinhole was quickly sealed with PP tape. The tape attached to the bag was 4.5 cm long. 2 It fits within the following area: In addition, when the film constituting the bag was a microporous film, the micropores were not blocked with tape. (2) Initial oxygen concentration measurement The initial oxygen concentration (C0) inside the bag was measured immediately after filling with nitrogen gas (t=0). The gas inside the bag was sampled and the initial oxygen concentration (C0) inside the bag was determined using gas chromatography (TCD). C0 was 0.2% or less, and if it exceeded this, the process was repeated. The amount of sampled gas used for oxygen concentration measurement was 10cc or less. When injecting into gas chromatography, a fixed amount of approximately 1cc was injected. In addition, measurements of standard gases (two or more points including approximately 1% and approximately 10% oxygen) were also performed by injecting the same amount of gas, and a calibration curve was created. (3) Storage of bags The bags used to measure the initial oxygen concentration were stored at 23°C and 60% RH (in a temperature and humidity chamber) while being kept stationary so that no objects were placed on top of the bags and the air from the fan in the temperature and humidity chamber did not directly hit the bags. (4) Measurement of oxygen concentration inside the bag during storage and calculation of oxygen transmission rate The oxygen concentration inside the bag is measured immediately after filling with nitrogen gas and after three or more hours, with the oxygen concentration between 1% and 7%. Two or more measurements are taken at three to five points in total. A proportional relationship (a correlation coefficient of 0.98 or greater) must be established between the elapsed time (t) and the oxygen concentration inside the bag. If the correlation coefficient is not established, the test is repeated. If the oxygen transmission rate of the film making up the bag is too high, causing the oxygen concentration inside the bag to rise too quickly, and this condition cannot be met, a bag can be created by laminating a portion of the film with a smaller, known film of the same material. The surface area of ​​the bag is then excluded from the portion laminated with the known film. The oxygen transmission rate of the measured film is calculated by subtracting the oxygen transmission rate of the known film from the calculated oxygen transmission rate. The oxygen transmission rate was calculated using the value for the longer elapsed time using the following formula (1). F=1.143×(Ct-C0)×V / t (1) However, F: oxygen permeation rate (cc / bag day atm) Ct: Oxygen concentration in the bag t hours after filling with nitrogen gas (%) C0: Oxygen concentration in the bag immediately after filling with nitrogen gas (%) V: Amount of nitrogen gas filled (cc) t: Time elapsed since gas filling (hr)

[0058] Measurement of the average pore size (μm) of the through-holes Using a microscope (Keyence VH-6300), the area of ​​five holes on the inner surface of the packaging bag was measured. Assuming that the holes were perfectly round, the diameter was calculated from the area of ​​the holes, and the average diameter was calculated.

[0059] Measurement of the opening area (Sout) of the through-holes on the outer surface of the packaging bag and the opening area (Sin) of the through-holes on the inner surface of the packaging bag: Using a microscope (Keyence Corporation, VH-6300), the opening area of ​​the through-holes in the packaging bag (20°C) was measured on both the inner and outer surface sides.

[0060] The inner surface area of ​​the packaging bag per 100g of fruit or vegetable (cm 2 ) calculation Packaging bag size (inner dimensions) (cm 2 The calculation was made by dividing twice the value of the total amount of fruit and vegetables (g) by 100.

[0061] <Evaluation> Each of the packages containing fruits and vegetables obtained above was stored at 10°C for 5 days. After that, the cut cabbage was removed from the package and comprehensively evaluated by several expert panelists for "presence or absence of discoloration," "quality of texture," and "quality of flavor."

[0062] Freshness retention period - 1: Remove the contents from two samples (packages) and measure the general viable bacteria count using 3M Petrifilm (AC plate). The average general viable bacteria count is 10 6 The number of days until the gas concentration reached or exceeded the limit was measured. Multiple samples were prepared and measurements were taken once a day. Since the gas concentration in the packaged body of the sample after measurement changed significantly, the sample was not used for subsequent measurements, and a different sample was used to repeat the measurement process the next day. Freshness retention period - 2: The contents were taken out from two samples (packages), and the number of E. coli bacteria was measured using 3M Petrifilm (CC plate). The average number of E. coli bacteria was 10 2 The number of days until the gas concentration reached or exceeded the limit was measured. Multiple samples were prepared and measurements were taken once a day. Since the gas concentration in the packaged body of the sample after measurement changed significantly, the sample was not used for subsequent measurements, and a different sample was used to repeat the measurement process the next day.

[0063] [Table 1]

Claims

1. A package containing fruits and vegetables, in which fruits and vegetables are packaged in a packaging bag made of a synthetic resin film, The rate of change in oxygen concentration in the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment)×100] (%) is 0.5% or more and 400% or less, Oxygen permeability at 23°C and 60% RH is 2 cc / m ２ ・Day・ATM or more, 50000cc / m ２ - Packaging containing fruits and vegetables that is below day-atm. Treatment: The package is stored under conditions of 20°C and 50% RH for 3 days.

2. Water vapor permeability at 40°C is 2 g / m ２ ・Over 400g / m ２ The package containing fruits and vegetables according to claim 1, wherein the shelf life is 10 days or less.

3. The inner area of ​​the packaging bag per 100 g of the fruit or vegetable is 100 cm ２ More than 5000cm ２ The fruit and vegetable package according to claim 1 or 2, wherein:

4. The package containing fruit or vegetable according to claim 1 , wherein the packaging bag has a through-hole.

5. The number of the through holes relative to the inner area of ​​the packaging body is 1 / m ２ More than 1500 pieces / m ２ The package containing fruits and vegetables according to claim 4, wherein:

6. The fruit and vegetable package according to claim 4 or 5, wherein the through holes have an average pore size of 30 μm or more and 1100 μm or less.

7. The fruit and vegetable package according to claim 1 , wherein the synthetic resin film has a thickness of 15 μm or more and 150 μm or less.

8. A package containing fresh produce described in any one of claims 4 to 7, wherein, for the through holes, when the hole area on the outer surface of the fresh produce freshness-keeping packaging bag is Sout and the hole area on the inner surface of the fresh produce freshness-keeping packaging bag is Sin, Sout / Sin > 1.

1.

9. A method for preserving the freshness of fruits and vegetables by packaging the fruits and vegetables in a packaging bag made of a synthetic resin film, The rate of change in oxygen concentration in the package before and after the following treatment [(oxygen concentration after treatment) / (oxygen concentration before treatment)×100] (%) is 0.5% or more and 400% or less, Oxygen transmission rate (cc / m) at 23°C and 60% RH ２ A method for preserving the freshness of fruits and vegetables, which comprises packaging the fruits and vegetables so that the freshness factor (day / atm) is 2 or more and 50,000 or less. Treatment: The package is stored under conditions of 20°C and 90% RH for 3 days.

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