JP6439275B2 - Fruit and vegetable freshness-maintaining packaging bag, package containing fruits and vegetables using the same, and method for maintaining freshness of fruits and vegetables - Google Patents

Description

  The present invention relates to a fruit and vegetable freshness-keeping packaging bag, a fruit and vegetable package using the same, and a fruit and vegetable freshness keeping method.

The fruits and vegetables continue to breathe after harvesting. Therefore, the deterioration of the harvested fruits and vegetables is more likely to progress as breathing is more active. The respiration of fruits and vegetables is suppressed in a low oxygen and high carbon dioxide environment that is moderate to the atmosphere. When fruits and vegetables are stored under such conditions, deterioration and ripening of the fruits and vegetables are suppressed.
In recent years, methods for maintaining the freshness of fruits and vegetables have been used as packaging methods for fruits and vegetables. This is a technique called MA (Modified Atmosphere) packaging, which is more suitable than the atmosphere suitable for storage of fruits and vegetables by adjusting the balance between the breathing rate of the fruits and vegetables packed by the packaging material and the gas transmission rate of the packaging materials. Achieving moderate low oxygen and high carbon dioxide conditions. However, in the case of MA packaging, even when fruits and vegetables are packaged using a film made of a material such as polypropylene or polyethylene, the amount of permeation of gas such as oxygen may still be insufficient. In such a case, due to the lack of oxygen in the package, it is necessary to take measures against the problem that fruits and vegetables breathe abnormally and promote deterioration (Patent Documents 1 and 2, etc.).

  In order to solve these problems, Patent Documents 1 and 2 propose a method using a perforated film as a method for controlling the respiration rate of fruits and vegetables and maintaining freshness.

In patent document 1, the opening area ratio of the film in a packaging bag containing green soybeans is 1.1 × 10 ⁻⁴ to 1 × 10 ⁻³ %, and the bag inner area per 100 g of green soybeans is 200 to 600 cm ^2. Is described as good.

In Patent Document 2, the opening area ratio of the film in the packaging bag with green soybeans is 1 × 10 ⁻⁶ to 1 × 10 ⁻⁴ %, and the bag inner area per 100 g of green soybeans is preferably ²⁰⁰ to 600 cm ^2. It is described.

JP 2006-204194 A JP 7-184538 A

  When fruits and vegetables are packaged using the films described in Patent Documents 1 and 2, molds may occur in the packaged fruits and vegetables. In addition, as a technique used for preserving fruits and vegetables, there has been a technique for maintaining the freshness of fruits and vegetables, but a technique for suppressing mold generation has not been reported so far.

  In addition, when fruits and vegetables are packaged using the films described in Patent Documents 1 and 2, maintaining the freshness of the packaging bag in the process from packaging the fruits and vegetables to the market depending on the temperature conditions during storage. There was also a variation in performance. Specifically, when a packaging bag is designed so that an optimum MA atmosphere can be constructed at 5 ° C., the freshness of fruits and vegetables may not be sufficiently maintained at a temperature of about room temperature (25 ° C.). On the other hand, when a packaging bag is designed so that an optimal MA atmosphere can be constructed at room temperature (25 ° C.), the freshness of fruits and vegetables may not be sufficiently maintained under a low temperature condition of about 5 ° C.

  Therefore, the present invention provides a freshness-keeping packaging bag for fruits and vegetables that can suppress the occurrence of mold in the preserved fruits and vegetables while keeping the freshness of the fruits and vegetables and can cope with changes in the preservation conditions of the fruits and vegetables.

  The present inventors diligently studied each of the causes of molds in MA-wrapped fruits and vegetables and the causes of variations in the freshness retention performance of the packaging bags. As a result, with respect to the porous synthetic resin film, if the dimensional stability of the porous synthetic resin film is improved under room temperature (25 ° C.) conditions, generation of mold can be suppressed and We obtained the knowledge that a fruit and vegetable freshness-keeping packaging bag that can respond to changes can be realized. Specifically, for the perforated synthetic resin film, it has been found that a measure of the dimensional stability of the perforated synthetic resin film measured under specific conditions at room temperature (25 ° C.) is effective as such a design guideline. The present invention has been reached.

According to the present invention,
A fruit and vegetable freshness-keeping packaging bag composed of a perforated synthetic resin film,
The porous synthetic resin film is provided with one or more through holes,
The through-hole is a fruit and vegetable freshness-keeping packaging bag that satisfies the following conditions, and is the maximum of the perforated synthetic resin film in an area within 10 mm from the outer periphery of the through-hole on the outer surface of the fruit and vegetable freshness-holding packaging bag. When the thickness is Tmax and the minimum thickness is Tmin, a fruit and vegetable freshness-maintaining package in which the ratio of the maximum thickness to the minimum thickness Tmax / Tmin is 1.05 or more and 8.00 or less.
Conditions: Cut out the test piece of the perforated synthetic resin film into a rectangular shape of 20 cm × 25 cm so as to include one through hole, and place it at the center of the short side of the test piece under room temperature (25 ° C.) condition. at the time of applying a load of 9N 60 minutes, the opening area of the through hole before loading the pre-yn heavy S _0, the opening area of the through hole after preloading the yn heavy was S ₁ At this time, the dimensional stability calculated by the following formula (1) is 6.0% or more and 9.0% or less.
Formula: Dimensional stability ratio [%] = {(S1 / S0) -1} × 100 (1)

  Moreover, according to this invention, the package containing fruits and vegetables formed by sealing fruits and vegetables with the said fruits and vegetables freshness maintenance packaging bag is provided.

  Moreover, according to this invention, the fruit and vegetables freshness maintenance method which packages fruits and vegetables using the said fruit and vegetables freshness maintenance packaging bag is provided.

  ADVANTAGE OF THE INVENTION This invention can provide the fruit and vegetables freshness maintenance packaging bag which can suppress generation | occurrence | production of mold | fungi in the preserved fruit and vegetables, and can respond to the change of the preservation conditions of fruit and vegetables, maintaining the freshness of fruit and vegetables.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

The fruit and vegetable freshness-keeping packaging bag in the present embodiment is composed of a perforated synthetic resin film provided with one or more through holes. And this porous synthetic resin film has the through-hole which satisfy | fills the following conditions. By doing this, while maintaining the freshness of the fruits and vegetables, it is possible to suppress the occurrence of mold in the preserved fruits and vegetables, and to provide a freshness and vegetable packaging bag that can cope with changes in the preservation conditions of the fruits and vegetables.
Conditions: Cut out the test piece of the perforated synthetic resin film into a rectangular shape of 20 cm × 25 cm so as to include one through hole, and place it at the center of the short side of the test piece under room temperature (25 ° C.) condition. When the opening area of the through hole before loading the load on the test piece when the load of 9N is applied for 60 minutes is S0, and the opening area of the through hole after load loading on the test piece is S1, the following formula The dimensional stability calculated in (1) is 6.0% or more and 9.0% or less.
Formula: Dimensional stability ratio [%] = {(S1 / S0) -1} × 100 (1)

First, the principle of mold generation in fruits and vegetables will be described.
It is known that mold generated in fruits and vegetables grows on the principle described below. First, mold spores adhere to the surface of the fruits and vegetables. Thereafter, mold spores adhering to the surface of the fruits and vegetables germinate and grow to form colonies. The formed colonies grow with time and become large enough to be confirmed with the naked eye. In this way, mold is generated on the surface of the fruits and vegetables.

Next, conditions for easy growth of mold will be described.
In order for mold to grow, it is premised that the conditions of the growth environment such as temperature, humidity, oxygen content and pH are met. In general, mold growth is said to be slower at lower temperatures and lower humidity, and faster at higher temperatures and humidity. However, even if mold spores adhere to the surface of the fruits and vegetables, molds may not be generated if the growth conditions are not met.

  When fruits and vegetables are stored using a conventional freshness-maintaining packaging bag, the cause of mold on the surface of the fruits and vegetables is not necessarily clear, but the freshness-maintaining packaging bag contains the respiration of the fruits and vegetables stored in the freshness-maintaining packaging bag. This is considered to be because the conditions such as temperature, humidity, oxygen amount and pH were easily changed to conditions suitable for mold generation. In addition, as described above in the section of the problem to be solved by the invention, a technique for suppressing the generation of mold has not been reported so far.

  Also, when fruits and vegetables are stored using conventional freshness-keeping packaging bags, the freshness-holding performance of the packaging bags in the process from packaging of fruits and vegetables to distribution to the market varies depending on the temperature conditions during storage. Sometimes it happens. As described above, when the freshness holding performance of the packaging bag has a variation, it is considered that the product value of the fruits and vegetables distributed in the market also varies. The cause of this is not necessarily clear, but it is considered that the through-hole provided in the conventional packaging bag has adopted a configuration whose shape tends to change due to the weight of the fruits and vegetables to be stored.

  In fact, when considering the storage of fruits and vegetables in the freshness-keeping packaging bags that are produced and distributing them to the market, the temperature changes due to changes in weather, seasonal changes, etc., even in the same region / location. Considering that the temperature varies depending on the region / location where fruits and vegetables are distributed even in the season, the freshness of fruits and vegetables that can always maintain a constant freshness-retaining performance regardless of the temperature conditions during storage (for example, 0 ° C to 40 ° C) It was necessary to realize a holding packaging bag. That is, it has been necessary to realize a fruit and vegetable freshness-keeping packaging bag that can cope with changes in the storage conditions of fruits and vegetables.

  Therefore, in the fruit and vegetable freshness-keeping packaging bag according to the present embodiment, the dimensional stability rate calculated from the opening area of the through hole measured under the above-mentioned specific conditions for the porous synthetic resin film is 6.0% or more and 9.0% or less. The structure which becomes is adopted. By doing this, it is not always clear why the fruit and vegetables freshness-keeping packaging bag that can suppress the occurrence of mold and can cope with changes in the storage conditions of fruits and vegetables is not clear, but the shape of the through hole provided in the packaging bag is stable. This is considered to be because the sex is sufficiently controlled. Specifically, the fruit and vegetable freshness-holding packaging bag according to the present embodiment employs a specific configuration in which the shape stability of the through hole is enhanced as described above, so while maintaining the freshness of the fruit and vegetables, It is considered that molds can be prevented from being generated in the preserved fruits and vegetables, and the change in the preservation conditions of the fruits and vegetables can be sufficiently coped with.

  In addition, in the conventional freshness-keeping packaging bags, there have been techniques that focus on the technology for controlling the shape of the through holes and the materials for forming the packaging bags in order to preserve the freshness of fruits and vegetables. However, no technology has been reported so far that focuses on controlling the shape stability of the through-holes in order to reduce the influence of the weight of the fruits and vegetables on the shape of the through-holes.

In this embodiment, the dimensional stability factor calculated from the opening area of the through hole measured under the specific conditions described above is 6.0% or more, and preferably 6.1% or more. By doing so, the freshness of fruits and vegetables can be stably maintained for a longer period even when the temperature condition changes.
In addition, while maintaining the freshness of fruits and vegetables as in this embodiment, it is possible to suppress the occurrence of mold in the preserved fruits and vegetables, and to realize a freshness-keeping packaging bag that can cope with changes in the preservation conditions of fruits and vegetables, It is considered to be particularly important to control the lower limit value of the dimensional stability factor described above. In this regard, the inventors of the present application have intensively studied the influence of the value of the dimensional stability calculated for the through-hole drilled in the packaging bag on the freshness-maintaining function of the freshness-maintaining packaging bag. As a result, the freshness-maintaining packaging bag has It has been found that the freshness maintaining function may not be sufficiently developed even if the value of the dimensional stability factor calculated from the value of the opening area measured under the specific conditions is slightly changed. The “slight change” described above means that the value of the dimensional stability factor changes in units of 0.1%. Moreover, the influence which the value of a dimensional stability factor has on the freshness-keeping function of the freshness-keeping packaging bag will be specifically described by showing experimental results in examples described later.

  Moreover, in this embodiment, the dimensional stability factor calculated from the opening area of the through-hole measured on the specific conditions mentioned above is 9.0% or less, Preferably, it is 8.5% or less. By carrying out like this, the mold prevention performance of the said packaging bag can be strengthened further.

Next, the holes provided in the perforated synthetic resin film will be described. A through hole may be provided in the fruit and vegetable freshness-keeping packaging bag according to the present embodiment.
The planar shape of the through hole on the outer surface of the fruit and vegetable freshness holding packaging bag and the planar shape of the through hole on the inner surface of the fruit and vegetable freshness holding packaging bag are not particularly limited, but are, for example, circular, polygonal, and slit shapes There is. Moreover, the notch provided in the film may be sufficient as the through-hole which concerns on this embodiment. Here, the “circular shape” is not limited to a true circle, and may be substantially circular. In addition to the circular shape, an elliptical shape, a semicircular shape, and a crescent shape may be used. The “polygon” may be a shape surrounded by three or more line segments such as a triangle, a quadrangle, and a pentagon.

  Moreover, in the said fruit and vegetable freshness maintenance packaging bag, it is preferable that the planar shape of the through-hole in an outer surface and the planar shape of the through-hole in an inner surface are substantially the same shape.

  Moreover, when it is set as a slit-shaped through-hole, it is necessary to be able to adjust the balance between the respiration rate of fruits and vegetables and the gas transmission rate of the packaging material. In addition, a circular through hole is desirable from the viewpoint of opening work or the like. By doing so, even when the use conditions change, the variation in the degree of freshness deterioration of the fruits and vegetables can be further suppressed.

  The average hole diameter (diameter) of the through holes is preferably 20 μm or more and 2000 μm or less, and more preferably 30 μm or more and 800 μm or less. When the average hole diameter of the through holes is within the above range, variation in the degree of deterioration of the fruits and vegetables can be further suppressed even when the use conditions are changed. In addition, when the average hole diameter of a through-hole is 20 micrometers or more, the outstanding fruit and vegetables freshness holding packaging bag can be obtained from a viewpoint of productivity of a perforated synthetic resin film. When the average hole diameter of the through holes is 2000 μm or less, the number of holes necessary to obtain an appropriate opening area ratio can be maintained, so that an excellent fruit and vegetable freshness holding packaging bag can be obtained from the viewpoint of quality accuracy of freshness holding. it can.

  Further, when the through hole has a slit shape, there is no problem if the diameter in the major axis direction is, for example, 2000 μm or less. In addition, the calculation method of the opening area of an irregularly shaped hole can be obtained by, for example, calculating the area by dividing the shape into several shapes that are easy to calculate, and then calculating the total of each area.

  Moreover, the hole provided in the perforated synthetic resin film is good also as a structure which a liquid can ooze out. At this time, even if the hole is apparently blocked, it is sufficient that a liquid such as water oozes out. Further, for example, the pore diameter may be controlled so that water hardly oozes out at normal pressure and oozes out and released only during vacuum precooling.

  When the through-hole provided in the perforated synthetic resin film is a cut, the shape of the cut provided in the film is not particularly limited. The notch may be a single straight line or may be a combination of a plurality of straight lines, or a shape in which a straight crack has developed from the end of the hole, such as an ellipse or a circle. Shapes with curved parts such as letter shape, U shape, semi-circle, wave shape, V shape, L shape, H shape, T shape, W shape, U shape, x mark, etc. A shape having corners may be used. The shape of the notch is not limited to that shown here. For example, the shape provided with the main hole part and the elongate opening part extended to the outer side of the said main hole part from the peripheral part of the said main hole part may be sufficient. In addition, you may use the shape of a notch in combination of multiple types.

  Here, the planar shape of the through hole according to the present embodiment is a shape provided with a main hole and a long opening extending outside the main hole starting from the peripheral edge of the main hole. It is preferable. By doing so, the anti-mold performance of the packaging bag can be further improved. The reason for this is not necessarily clear, but it is thought that by controlling the shape of the through-hole, the environment in the freshness-keeping packaging bag becomes a condition that is not suitable for mold growth.

  Hereinafter, for the packaging bag according to the present embodiment, the planar shape of the through hole includes the main hole portion and a long opening extending outside the main hole portion from the peripheral edge portion of the main hole portion. The case will be described in detail by taking the case of the shape as an example.

  Although the planar shape of the main hole part which concerns on this embodiment is not specifically limited, For example, there exist shapes, such as circular, a polygon, and a slit. Here, the “circular shape” is not limited to a true circle, and may be substantially circular. In addition to the circular shape, an elliptical shape, a semicircular shape, and a crescent shape may be used. The “polygon” may be a shape surrounded by three or more line segments such as a triangle, a quadrangle, and a pentagon. The planar shape of the main hole portion is preferably a circular shape from the viewpoint of opening work or the like. By doing so, even when the use conditions change, the variation in the degree of freshness deterioration of the fruits and vegetables can be further suppressed.

  Moreover, it is preferable that the average hole diameter (diameter) of a main hole part is 20 micrometers or more and 2000 micrometers or less, respectively, More preferably, they are 30 micrometers or more and 800 micrometers or less. When the average hole diameter of the main hole is within the above range, deterioration of fruits and vegetables can be more effectively suppressed even when the use conditions are changed. In addition, when the average hole diameter of a main hole part is 20 micrometers or more, the outstanding fruit and vegetables freshness maintenance packaging bag can be obtained from a viewpoint of productivity of a perforated synthetic resin film. When the average hole diameter of the main hole portion is 2000 μm or less, the number of holes necessary to obtain an appropriate opening area ratio can be maintained, so that an excellent fruit and vegetable freshness-keeping packaging bag can be obtained from the viewpoint of quality accuracy of freshness keeping. Can do.

Next, the long opening of the through hole will be described.
In the through-hole provided in the fruit and vegetable freshness-keeping packaging bag according to the present embodiment, one or more elongated openings are provided. The planar shape of the elongated opening is not particularly limited. The planar shape of the elongated opening may be a single straight line or may be a combination of a plurality of straight lines, and a straight crack has developed from the end of the hole, such as an ellipse or a circle. It may be a shape, a shape having a curved portion such as an S shape, a U shape, a semicircle, a wave shape, a V shape, an L shape, an H shape, a T shape, a W shape, It may be a U shape or a shape having a corner such as a cross. The planar shape of the elongated opening is not limited to that shown here. A plurality of types of planar shapes of the elongated openings may be used in combination.

  Moreover, the size (length) of the long opening of the through hole according to the present embodiment is not particularly limited, but is preferably 160 μm or more and 25000 μm or less, and more preferably 250 μm or more and 3000 μm or less. By doing so, the anti-mold performance of the packaging bag can be further enhanced. In the present embodiment, the size (length) of the long opening of the through hole is the total length from the peripheral edge (outer periphery) of the main hole to the tip of the long opening. Refers to the value. In particular, the length from the peripheral edge portion (outer periphery) of the main hole portion to the distal end portion of the elongated opening portion in the present embodiment refers to the total length of the length along the notch shape. For example, when two straight long openings are provided, the size (length) of the long openings is equal to the length of the two long openings. It is the total value. Moreover, when it is set as the elongate opening part of the shape where the some straight line connected, the magnitude | size (length) of an elongate opening part becomes a total value of the length of all the straight lines.

  In the present embodiment, the maximum thickness of the perforated synthetic resin film is Tmax and the minimum thickness in a region within 10 mm from the outer periphery of the through hole on the outer surface of the fruit and vegetable freshness holding packaging bag (hereinafter also referred to as “hole peripheral region”). Is Tmin, the ratio Tmax / Tmin between the maximum thickness and the minimum thickness of the porous synthetic resin film is preferably 1.05 or more, more preferably 1.50 or more. By doing so, even when the temperature changes, the size of the through hole is stabilized, so that deterioration or decay of fruits and vegetables can be more stably suppressed. The ratio Tmax / Tmin between the maximum thickness and the minimum thickness of the perforated synthetic resin film in the peripheral region of the hole on the outer surface of the fruit and vegetable freshness holding packaging bag is 8.00 or less, and preferably 6.00 or less. By doing so, even when the temperature changes, the size of the through hole is stabilized, so that deterioration or decay of fruits and vegetables can be further stably suppressed over time. Here, the region (hole peripheral region) within 10 mm from the outer periphery of the through hole on the outer surface of the fruit and vegetable freshness holding packaging bag is drawn from the center point of the through hole so as to pass through the peripheral portion (outer periphery) of the through hole. On the straight line, it refers to the range from the intersection of the straight line and the peripheral edge of the through hole to a location 10 mm away from the center point of the through hole.

  In the present embodiment, the maximum thickness Tmax of the perforated synthetic resin film in the region around the hole on the outer surface of the fruit and vegetable freshness holding packaging bag is appropriately selected according to the type of fruit and vegetable. The maximum thickness Tmax of the perforated synthetic resin film is, for example, 16 μm or more and 400 μm or less, and preferably 20 μm or more and 300 μm or less.

  Further, the minimum thickness Tmin of the perforated synthetic resin film in the region around the hole on the outer surface of the fruit and vegetable freshness holding packaging bag is appropriately selected according to the type of fruit and vegetable. The minimum thickness Tmin of the perforated synthetic resin film is, for example, 15 μm or more and 60 μm or less, and preferably 20 μm or more and 50 μm or less.

In this embodiment, the oxygen permeation amount at 35 ° C. and 90% RH of the perforated synthetic resin film constituting the freshness-keeping packaging bag for fruits and vegetables is 100000 mL / 100 g · m ² · day · atm or more, preferably 200000 mL / 100 g. · M ² · day · atm or more, more preferably 300000 mL / 100 g · m ² · day · atm or more. By doing this, while maintaining the freshness of the fruits and vegetables, it is possible to provide products (fruits and vegetables) that have a good appearance. Moreover, the oxygen permeation | transmission amount in 35 degreeC and 90% RH of the porous synthetic resin film which comprises a fruit and vegetables freshness preservation packaging bag is 800000 mL / 100g * m < ² > * day * atm or less, Preferably it is 700000mL / 100g * m < ² >. • Day · atm or less, more preferably 600000 mL / 100 g · m ² · day · atm or less. By doing so, it is possible to suppress the fading of the preserved fruits and vegetables while maintaining the freshness of the fruits and vegetables.

Next, the water vapor permeability of the holes will be described.
The water vapor transmission rate at 40 ° C. and 90% RH of the porous synthetic resin film is, for example, 4 g / m ² · day or more from the viewpoint of further improving the freshness maintaining effect of fruits and vegetables at a high temperature, and 20 g / m ² · It is preferably day or more. Moreover, there is no restriction | limiting in particular in the upper limit of the water-vapor-permeation rate in 40 degreeC and 90% RH, but it is 400 g / m < ² > * day or less, for example from a viewpoint of preventing withering.

Next, the manufacturing method of the fruit and vegetables freshness maintenance packaging bag in this embodiment is demonstrated.
In order to obtain the fruit and vegetable freshness-keeping packaging bag according to the present embodiment, it is necessary to provide a hole having a predetermined shape at a predetermined position of the film or the film processed into a bag shape. However, it is difficult to obtain a fruit and vegetable freshness-maintaining packaging bag having a dimensional stability factor according to the present embodiment that satisfies the above-described specific conditions by the conventional method for producing a perforated film described in the background section.

Specifically, the fruit and vegetable freshness-keeping packaging bag of the present embodiment includes, for example, various factors relating to the following three conditions (for example, the type of perforated synthetic resin film, the type of means used for perforation, and the model number of the device used) Can be manufactured for the first time by appropriately adjusting the shape and the like. Thus, in order to obtain a fruit and vegetable freshness holding packaging bag that can suppress the occurrence of mold in the preserved fruit and vegetables while maintaining the freshness of the fruit and vegetables according to the present embodiment, and can cope with changes in the preservation conditions of the fruit and vegetables. For example, it is particularly important to highly control various factors related to the following three conditions.
(1) Selection of material (resin material, stretchability, etc.) for forming a porous synthetic resin film (2) Drilling conditions and method for through holes (3) Thickness of the porous synthetic resin film

  Hereinafter, the example of the various factors which concern on the manufacturing method of the fruit and vegetables freshness-keeping packaging bag which concerns on this embodiment is demonstrated. However, the manufacturing method of the fruit-and-fruit freshness holding packaging bag of this embodiment is not limited to the following examples. Moreover, an example of the manufacturing method of the fruit-and-fruit freshness holding packaging bag of this embodiment is later mentioned concretely in an Example.

First, the raw material which forms a perforated synthetic resin film is demonstrated.
The synthetic resin constituting the porous synthetic resin film is not particularly limited as long as it can be used for packaging fruits and vegetables. For example, various polyethylenes and ethylene copolymers, polypropylene, polyvinyl chloride, polystyrene, acrylic resins And polyester resins such as polyethylene terephthalate and polylactic acid, and polyamide resins such as 6 nylon. These may be homopolymers, may be two or more types of copolymers, and may be a blend containing two or more types of these homopolymers and copolymers.
More specifically, the various polyethylenes and ethylene copolymers include high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, metallocene-linear low density polyethylene, ethylene-vinyl acetate copolymer, Copolymers such as ethylene-acrylic acid copolymer, ethylene-propylene copolymer, and ethylene-α-olefin copolymer, ionomers, and the like may be mentioned, or a blend of two or more of these with other resins may be used.

  Furthermore, a film obtained by molding the synthetic resin exemplified above may be used as a single layer film, or may be used in the form of a multilayer film having two or more layers.

  The method for forming the film is not particularly limited, and methods such as extrusion, inflation, and calendering are used. When the film is formed, additives such as an antifogging agent may be kneaded as necessary, or two or more kinds of resins may be blended. Further, the film may be stretched or annealed. These films may be provided with a sealant layer, or may be a film coated to give some function. Further, these films may be transparent, opaque, or printed.

  In particular, it is preferable to use an anti-fogging stretched polypropylene film, a low-density polyethylene film, a linear low-density polyethylene film, or a metallocene-catalyzed polyethylene as a synthetic resin film from the viewpoints of cost and physical properties.

  In addition, when the contents to be packed in the freshness-keeping packaging bag for fruits and vegetables are heavy, polyethylene is dry-laminated and extruded into films such as unstretched polypropylene, stretched polypropylene, unstretched nylon, stretched nylon and stretched polyester as synthetic resin films. You may use what was made into the multilayer film by lamination and coextrusion.

Next, the thickness of the perforated synthetic resin film will be described.
The thickness of the film used for the fruit and vegetable freshness-keeping packaging bag in the present embodiment may be, for example, 15 μm or more and 400 μm or less. If the film is too thin, the strength may be insufficient. On the other hand, if the film is too thick, the production cost increases, so the practicality decreases. Furthermore, these films may be transparent or opaque, and there is no problem even if the surface is printed.

Next, a method for drilling through holes will be described.
The through-hole according to the present embodiment employs a shape having, for example, a main hole and a long opening extending outside the main hole from the peripheral edge of the main hole. For the through hole having such a planar shape, it is necessary to form a long opening using some means after forming the main hole.

  Processing of the main hole portion of the through hole is not particularly limited, but may be a processing method using a laser or a needle processing method including hot needle processing. However, in order to obtain the through hole according to the present embodiment, it is necessary to appropriately control the shape of the support base on which the film that is the object to be drilled is mounted, the insertion angle of the laser and the needle, and the like.

  The long opening of the through hole must be processed in a way that the shape of the long opening that can be obtained cannot be predicted in advance, such as the method of tearing from the peripheral edge of the main hole with both ends of the film. There is no particular limitation. Examples of the processing method for the long opening include a method of cutting with a sharp blade such as a cutter, a method of punching with a die that can cut a desired shape, and a method of laser processing. Moreover, the timing which processes a long opening part is not specifically limited. You may carry out at the time of manufacture of a film, the time of bag making, or after bag making.

  However, in the through hole according to the present embodiment, as described above, after forming at least the main hole portion, it is necessary to create a long opening using some means that can predict the shape to be obtained in advance. .

  By doing so, it is possible to obtain a perforated synthetic resin film in which each factor such as the shape of the hole, the opening area of the hole, the position of the hole, and the hole diameter is highly controlled, and the freshness of the fruits and vegetables according to this embodiment is maintained. However, it is possible to obtain for the first time a packaging bag for maintaining the freshness of fruits and vegetables that can suppress the occurrence of mold in the preserved fruits and vegetables and can cope with changes in the storage conditions of the fruits and vegetables. In addition, regarding the selection of various factors such as the selection of film material and the perforation method and conditions when producing the fruit and vegetable freshness-keeping packaging bag in the present embodiment, in the examples described later, more detailed than the conventional manufacturing method Explained.

Moreover, the total opening area per bag of the fruit and vegetables freshness preservation packaging bag obtained by the manufacturing method in this embodiment is about 1 × 10 ⁻⁵ mm to ² mm ² per 100 g of the contents in the bag at 40 ° C. .

  In the fruit and vegetable freshness preservation packaging bag according to the present embodiment, fruits and vegetables are packaged, and more specifically, fruits and vegetables washed in the process from harvesting to packaging are packaged.

  Fruits and vegetables generally contain a lot of moisture, and they often condense in the package due to transpiration by respiration, and storage using the fruit and vegetable freshness-keeping packaging bag in this embodiment is suitable. Specific examples of fruits and vegetables include: mackerel, spinach, komatsuna, mizuna, beech, asparagus, cucumber sinus, lettuce, thyme, parsley, italian parsley, rosemary, oregano, lemon balm, chives, lavender, salad barnet, ramsyear, rocket , Dandy lion, nastatum, basil, arugula, watercress, morroheiya, celery, kale, leek, cabbage, cabbage, sardine, saladna, sanchu, fuki, nabana, chinsai, honey bee, seri, me cabbage, broccoli, cauliflower, ginger, radish, Carrot, burdock, radish, turnip, sweet potato, potato, yam, yam, taro, ginenjo, yamatomo, bell pepper, paprika, shishito, cucumber, eggplant, tomato Door, mini tomatoes, pumpkin, bitter gourd, okra, sweet corn, green soybean, peas, green beans, broad beans, Kinkinokorui, and the like. It is also effective for fruits such as citrus, apples, pears, grapes, blueberries, strawberries, strawberries, and cut flowers. These are also effective in a cut state, so-called cut vegetables and cut fruits.

  In this embodiment, since the fruits and vegetables washed with water or the fruits and vegetables wet with rain or dew can be packaged without draining, workability is improved. It is also possible to quickly evaporate all or part of the moisture of the fruits or vegetables, for example, to keep the fruits or vegetables cool to keep them fresh or to reduce the moisture to remove the effects of moisture on the fruits as soon as possible. . In such a case, the fruit and vegetables may be sealed in a fruit and vegetables freshness-keeping packaging bag according to the present embodiment, and vacuum precooled.

The package in the present embodiment is formed by sealing fruits and vegetables with the fruit and vegetable freshness-keeping packaging bag in the present embodiment.
Moreover, the freshness maintenance method in this embodiment includes the process of packaging fruits and vegetables using the freshness-keeping packaging bag for fruits and vegetables in this embodiment. It is necessary to seal the fruit and vegetables after they are packaged in the fruit and vegetable freshness preservation packaging bag.
Although it does not specifically limit as a sealing method, The method of using a heat seal, an adhesive tape, a rubber band, a string etc., methods, such as paste pasting and a zipper, are mentioned.

The area inside the packaging bag of the fruit and vegetable freshness-keeping packaging bag can be set according to the shape, size, density, and the like of the fruit and vegetable to be packaged. Then, the packaging body area of vegetables and fruits fresh-keeping packaging bag per fresh produce 100g is, for example 100 cm ² or more 5000 cm ² or less, preferably 200 cm ² or more 3000 cm ² or less.

  Further, from the viewpoint of more stably suppressing the progress of deterioration of fruits and vegetables, the oxygen concentration in the package containing fruits and vegetables is, for example, 0.1% or more and less than 19% in a state before opening the package, Is 1% or more and 17% or less.

  Further, from the viewpoint of maintaining the freshness of the fruits and vegetables more stably, the weight reduction rate of the whole package with fruits and vegetables is 0.05% by weight or more and less than 1% by weight, preferably 0.08% by weight. More than 0.9% by weight.

As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.
Hereinafter, examples of the reference form will be added.
1. A fruit and vegetable freshness-keeping packaging bag composed of a perforated synthetic resin film,
The porous synthetic resin film is provided with one or more through holes,
The said through-hole is a fruit and vegetables freshness maintenance packaging bag which satisfy | fills the following conditions.
Conditions: Cut out the test piece of the perforated synthetic resin film into a rectangular shape of 20 cm × 25 cm so as to include one through hole, and place it at the center of the short side of the test piece under room temperature (25 ° C.) condition. When an opening area of the through hole before load loading in the test piece when applying a load of 9 N for 60 minutes is S ₀ , and an opening area of the through hole after load loading in the test piece is S ₁ , The dimensional stability factor calculated by the following formula (1) is 6.0% or more and 9.0% or less.
Formula: Dimensional stability ratio [%] = {(S ₁ / S ₀ ) −1} × 100 (1)
2. The planar shape of the through hole includes a main hole and an elongated opening extending from the peripheral edge of the main hole to the outside of the main hole. The fruit and vegetable freshness-keeping packaging bag described in 1.
3. When the maximum thickness of the perforated synthetic resin film in the region within 10 mm from the outer periphery of the through hole is Tmax and the minimum thickness is Tmin on the outer surface of the freshness-keeping packaging bag for fruits and vegetables, the maximum thickness and the minimum thickness The ratio Tmax / Tmin is 1.05 or more and 8.00 or less. Or 2. The fruit and vegetable freshness-keeping packaging bag described in 1.
4). 2. The maximum thickness Tmax of the porous synthetic resin film is 16 μm or more and 400 μm or less. The fruit and vegetable freshness-keeping packaging bag described in 1.
5). 2. The minimum thickness Tmin of the porous synthetic resin film is 15 μm or more and 60 μm or less. Or 4. The fruit and vegetable freshness-keeping packaging bag described in 1.
6). 1. The oxygen permeation amount of the porous synthetic resin film at 35 ° C. and 90% RH is 100000 mL / 100 g · m ² · day · atm to 800,000 mL / 100 g · m ² · day · atm. To 5. The fruit and vegetable freshness-keeping packaging bag according to any one of the above.
7). 1. The water vapor permeability at 40 ° C. and 90% RH of the porous synthetic resin film is 4 g / m ² · day to 400 g / m ² · day. To 6. The fruit and vegetable freshness-keeping packaging bag according to any one of the above.
8). 1. To 7. A package containing fruits and vegetables formed by sealing the fruits and vegetables with the freshness-keeping packaging bag for fruits and vegetables according to any one of the above.
9. Of the vegetables and fruits containing packaging material, the packaging body area of the vegetables and fruits fresh-keeping packaging bag per the fresh produce 100g is 100 cm ² or more 5000 cm ² or less, 8. Packaging with fruits and vegetables as described in 1.
10. 7. The oxygen concentration in the package containing fruits and vegetables is 0.1% or more and less than 19% before opening the package containing fruits and vegetables. Or 9. Packaging with fruits and vegetables as described in 1.
11. 7. The weight reduction rate of the whole package with fruits and vegetables is 0.05% by weight or more and less than 1% by weight per day; To 10. A package containing fruits and vegetables according to any one of the above.
12 1. To 7. The fruit and vegetables freshness maintenance method which packages fruits and vegetables using the fruit and vegetables freshness maintenance packaging bag as described in any one of these.

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

Example 1
An anti-fogging biaxially oriented polypropylene film (hereinafter also referred to as “anti-fogging OPP”) (manufactured by Gunze Co., Ltd., trade name: Sylphan MV2, thickness 40 μm, bag size 140 mm × 180 mm) Nine holes (main holes) having a diameter of 180 μm (average diameter of main holes) and an opening area of 0.026 mm ² at 40 ° C. were provided. The total opening area of the main hole at 40 ° C. was 0.24 mm ² .

In this example, perforation was performed by the following method.
First, in order to produce the main hole portion of the through hole, a needle having a conical tip shape was prepared and attached to a perforating apparatus. The maximum diameter of this needle is 800 μm, and the height of the conical part is 4500 μm. Next, the film was mounted on the perforating apparatus so as not to cause wrinkles.
Next, by inserting a needle into the film, the side wall of the main hole portion of the through hole is a taper that spreads from the inside to the outside of the fruit and vegetable freshness holding packaging bag in the thickness direction of the perforated synthetic resin film. Perforation was performed so as to obtain a shape. By doing so, the side wall of the through hole provided in the fruit and vegetables freshness holding packaging bag was formed in a taper shape so as to gradually expand from the inner surface to the outer surface of the fruit and vegetable freshness holding packaging bag. In addition, the needle piercing speed with respect to the film was 0.5 m / s, and the drawing speed was 1.5 m / s. The planar shape on the outer surface of the main hole portion of the through hole and the planar shape on the inner surface were both circular and substantially the same shape.

  Next, in order to produce the cut end of the through hole, a sharp blade was prepared. At this time, the film having the main hole portion is still mounted in the punching device. Then, starting from the peripheral edge of the main hole portion of the through hole, the film is cut with a prepared blade so as to extend to the outside of the main hole portion, so that a long linear shape is obtained. An opening (length: 1200 μm) was produced. In addition, the elongate opening part was produced by the method mentioned above in all the through-holes. In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained.

(Example 2)
At the bottom of a bag of anti-fogging OPP (Toyobo Co., Ltd., trade name: Pyrene film-FG: P5562, thickness 25 μm, bag size 160 mm × 190 mm), diameter of 600 μm (average of main hole part) at 25 ° C. at 10 mm intervals 4 holes (main hole portions) having an opening area of 0.287 mm ² at 40 ° C. were provided. The total opening area of the main hole portion at 40 ° C. was 1.15 mm ² . In addition, perforation was performed using the same method as in Example 1 except that the needle insertion speed into the film was 1.0 m / s and the drawing speed was 1.0 m / s. . In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained.

Example 3
At the bottom of a bag of anti-fogging OPP (Toyobo Co., Ltd., trade name: Pyrene Film-FG: P5562, thickness 25 μm, bag size 160 mm × 190 mm), diameter 530 μm (average of main hole part) at 25 ° C. at 10 mm intervals 4 holes (main hole portions) having an opening area of 0.224 mm ² at 40 ° C. were provided. The total opening area of the main hole portion at 40 ° C. was 0.90 mm ² . In addition, perforation was performed using the same method as in Example 1 except that the needle insertion speed into the film was 1.0 m / s and the drawing speed was 1.0 m / s. . In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained.

(Example 4)
At the bottom of a bag of anti-fogging OPP (Toyobo Co., Ltd., trade name: Pyrene film-FG: P5562, thickness 25 μm, bag size 160 mm × 190 mm) at a distance of 10 mm at a diameter of 400 μm (average of main holes) 5 holes (main hole portions) having an opening area of 0.129 mm ² at 40 ° C. were provided. The total opening area of the main hole portion at 40 ° C. was 0.64 mm ² . In addition, perforation was performed using the same method as in Example 1 except that the needle insertion speed into the film was 1.0 m / s and the drawing speed was 1.0 m / s. . In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained.

(Example 5)
At the bottom of a bag of anti-fogging OPP (Toyobo Co., Ltd., trade name: Pyrene film-FG: P5562, thickness 25 μm, bag size 160 mm × 190 mm), diameter of 600 μm (average of main hole part) at 25 ° C. at 10 mm intervals 10 holes (main hole portions) having an opening area of 0.051 mm ² at 40 ° C. were provided. The total opening area of the main hole portion at 40 ° C. was 0.51 mm ² . In addition, perforation was performed using the same method as in Example 1 except that the needle insertion speed into the film was 1.0 m / s and the drawing speed was 1.0 m / s. . In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained.

(Example 6)
A fruit and vegetables freshness-keeping packaging bag was obtained in the same manner as in Example 1, except that two linear openings having a long shape were produced in all the through holes. Note that the length of the long opening was 1200 μm. In addition, the total value of the length of the long opening produced in the fruit and vegetable freshness-keeping packaging bag of Example 6 was 2400 μm.

(Comparative Example 1)
At the bottom of a bag of anti-fogging OPP (Toyobo Co., Ltd., trade name: Pyrene film-FG: P5562, thickness 25 μm, bag size 160 mm × 190 mm), diameter 6000 μm (average of the main hole portion) at 25 ° C. a diameter), and the opening area at 40 ° C. was provided four holes of 27.79mm ^2. The total opening area at 40 ° C. was 111.17 mm ² . For punching, punching was performed. In this way, a packaging bag for maintaining freshness of fruits and vegetables was obtained. In addition, the through-hole provided in the fruit and vegetables freshness holding packaging bag of the comparative example 1 is a thing which does not produce the elongate opening part.

(Comparative Example 2)
A fruit and vegetables freshness-keeping packaging bag was obtained in the same manner as in Example 1 except that the long opening was not produced.

(Comparative Example 3)
After producing the main hole, the fruit and vegetables freshness-maintaining packaging is the same as in Example 1 except that the film has both ends of the film and is torn from the peripheral edge of the main hole to produce a long opening. I got a bag.

  About the obtained fruit and vegetables freshness maintenance packaging bag, the measurement and evaluation shown below were performed.

In addition, for each measurement and evaluation, a packaging body in which green beans were packaged as described below was used.
20 packs of packaged bodies in which 180 g of green beans in a state of being washed with water were put in an average of 180 g each in Examples 1 to 6 and Comparative Examples 1 to 3 were sealed with a heat sealer. The packed package was packed in a cardboard box so that the bottom of the bag faces downward. In addition, the area in the package of the package containing shrimp was as follows. The packaging body area per 100 g of green beans of Examples 1 and 6 and Comparative Examples 2 and 3 was 280 cm ² , and the packaging body area per 100 g of green beans of Examples 2 to 5 and Comparative Example 1 was 337 cm ² .

  The package was stored at 5 ° C. for 5 days, and then stored at 40 ° C. for 2 days, and quality changes such as the appearance and smell of green soybeans were followed. In addition, it was observed with a microscope whether or not mold spores were attached to the surface of the green beans after being stored for 7 days under the above conditions.

(Example 7)
20 packs of broccoli containing 20 pieces of broccoli in a state of freshness and fruit freshness holding packaging bags of Example 1 were put in an average of 180 g each and sealed with a heat sealer. In addition, the packaging body area per 100 g of the broccoli was 280 cm ² . The broccoli-containing package was also stored for 5 days at 5 ° C. and then stored for 2 days at 40 ° C., and changes in quality such as the appearance and smell of broccoli were followed. In addition, the broccoli after storage for 7 days under the above conditions was observed with a microscope to determine whether mold spores were attached to the surface.

(Example 8)
20 grams of green beans that have been washed with water are placed in an average of 180 g each in the freshness-keeping packaging bag of Example 1 and sealed with a heat sealer to produce 20 packs. Packed to face. The package was stored at 5 ° C. for 7 days, and quality changes such as the appearance and smell of green soybeans were followed. In addition, it was observed with a microscope whether or not mold spores were attached to the surface of the green beans after being stored for 7 days under the above conditions.

Example 9
20 grams of green beans that have been washed with water are placed in an average of 180 g each in the freshness-keeping packaging bag of Example 1 and sealed with a heat sealer to produce 20 packs. Packed to face. The package was stored at 5 ° C. for 5 days and then stored at 25 ° C. for 2 days, and quality changes such as the appearance and odor of green soybeans were followed. In addition, it was observed with a microscope whether or not mold spores were attached to the surface of the green beans after being stored for 7 days under the above conditions.

(Evaluation item)
Dimensional stability: The dimensional stability was calculated using a perforated synthetic resin film used to produce a fresh fruit and vegetable packaging bag. Specifically, first, a test piece of the perforated synthetic resin film was cut into a rectangular shape of 20 cm × 25 cm so as to include one through hole. And the load of 4.9N was given to the center of the short side of the cut-out test piece for 60 minutes on room temperature (25 degreeC) conditions. About the through-hole which exists in this test piece, the opening area (S0) before load loading and the opening area (S1) after load loading were measured. Next, from the value of the obtained opening area (S0 and S1), the value calculated by the following formula (1) was defined as the dimensional stability factor. The unit is%.
Formula: Dimensional stability ratio [%] = {(S1 / S0) -1} × 100 (1)

Oxygen transmission amount: The oxygen transmission amount of the resin film at 35 ° C. and 90% RH was measured by the method described in (1) to (5) below. The unit was mL / 100 g · m ² · day · atm.
(1) Preparation of bag A packaging bag for maintaining freshness of fruits and vegetables was prepared using a film for measuring oxygen permeation. At this time, the bag was sealed with heat seal so that oxygen would not leak out from other than the through-holes of the film. The size of the bag to be measured was such that the inner surface area of the bag was 0.06 m ² or more. All the following operations were performed in the atmosphere.
(2) Entrapment of nitrogen gas After sealing the bag with heat sealing or the like, the bag was deaerated using an aspirator or the like. Deaeration was performed until both sides of the bag were stuck. Next, this bag was filled with nitrogen gas (purity 99.9% or more) using a white hard syringe. The amount of gas injected was determined by using the scale of the syringe barrel as much as possible without depending on the bag size, but in the range where the film was not tensioned. In addition, deaeration and nitrogen gas injection were performed by inserting an injection needle into a bag. When piercing the needle, a double-sided tape was attached to the film, and an adhesive tape made of polypropylene film (hereinafter referred to as “PP tape”) was attached thereon. Further, after removing the needle, the needle hole was immediately closed with PP tape. The tape affixed to the bag was made to fit within an area of 4.5 cm ² or less. In the case of a microporous film, care was taken not to block the micropores.
(3) Initial oxygen concentration measurement The initial oxygen concentration (C ₀ ) in the bag immediately after nitrogen gas filling (t = ₀ ) was measured. The gas in the bag was sampled, and the initial oxygen concentration (C ₀ ) in the bag was determined by gas chromatography (TCD). _C0 is 0.2% or less, and when it exceeds this, work is performed again. The sampling gas for measuring the oxygen concentration was 10 cc or less. When injecting into gas chromatography, about 1 cc of sampling gas was injected.
(4) Storage of bag The bag whose initial oxygen concentration was measured is stored at 23 ° C. and 60% RH (constant temperature and humidity chamber). At this time, it left still so that an object might not be put on a bag and the wind of the fan of a constant temperature and humidity chamber might hit directly.
(5) Measurement of oxygen concentration in the bag and calculation of oxygen permeation during storage The oxygen concentration in the bag is within the range of 1% or more and 7% or less immediately after filling with nitrogen gas and after 3 hours or more after filling. In total, three or more points were measured. Since it is necessary to establish a proportional relationship (correlation coefficient of 0.98 or more) between the elapsed time t (hr) and the oxygen concentration (C _t ) in the bag, a retest was performed when the correlation coefficient did not hold.
If the oxygen permeation amount of the film is too large and the oxygen concentration in the bag increases too quickly and this condition cannot be cleared, a part of the film is the same material with a known oxygen permeation amount and a smaller size than the film. A bag was made by laminating the film and the same process. At this time, the surface area of the bag was determined by subtracting the oxygen permeation amount of the known film portion from the obtained oxygen permeation amount, excluding the portion pasted with another known film. The oxygen permeation amount was calculated by the following calculation formula (2) using the value with the longer elapsed time.
F = 1.143 × (C _t −C ₀ ) × V / t / s (2)
However,
F: Oxygen permeation amount (mL / 100 g · m ² · day · atm)
C _t : oxygen concentration in bag (%) after t time after filling with nitrogen gas
C ₀ : oxygen concentration in bag immediately after filling with nitrogen gas (%)
V: Amount of nitrogen gas charged (cc)
t: Elapsed time from gas filling (hr)
s: surface area of the bag (m ² )

Maximum thickness Tmax and minimum thickness Tmin of film in hole peripheral region: The film thickness in the hole peripheral region was measured according to JIS K7130. Specifically, the thickness of the film at multiple points arbitrarily selected in the hole peripheral region was measured according to JIS K7130. And among the several measurement results regarding the thickness of the obtained film, the maximum value was set to Tmax and the minimum value was set to Tmin. The unit was μm. Here, the hole peripheral area refers to an area within 10 mm from the outer periphery of the through hole on the outer surface of the fruit and vegetable freshness-keeping packaging bag, and a straight line passing through the peripheral portion (outer periphery) of the through hole from the center point of the through hole. When drawn, it refers to the range from the intersection of the straight line and the peripheral edge of the through hole to a location 10 mm away from the center point of the through hole on the straight line.

Water vapor transmission rate: The water vapor transmission rate at 40 ° C. and 90% RH was measured according to JIS K7129: 2008. The unit was g / m ² · day.

Oxygen concentration: The oxygen concentration in the package at 40 ° C. and 5 ° C. was measured using a gas chromatograph (GC323, GC323) after sampling the air in the package before opening the package. The unit is%.

Weight reduction rate: The weight reduction rate at 40 ° C. and 5 ° C. was measured by the following procedure. First, about the weight of the bag which packed 100 g of green soybeans, the weight (W0) on the first test day and the weight (W7) on the seventh day after the start of the test were measured with an electronic balance. Next, from the weight of the obtained bag, a value calculated by the following calculation formula (3) was defined as a weight reduction rate. The unit was weight%.
Weight reduction rate = (W0−W7) / W0 × 100 (3)

  The evaluation results regarding the above evaluation items are shown in Table 1 and Table 2 below.

  Each of the packaging bodies of Examples 1 to 6, 8 and 9 was stored at 5 ° C for 5 days and then stored at 5 ° C, 25 ° C or 40 ° C for 2 days, and the quality changes such as the appearance and smell of green soybeans were traced. As a result, all were in good condition for a total of 7 days (packaging bodies of Examples 1 to 6, 8 and 9). On the other hand, the green beans preserved using the fruit and vegetable freshness-keeping packaging bags of Comparative Examples 1 to 3 were deflated and were not sweet.

  The package of Example 7 is obtained by packaging broccoli instead of green beans in the fruit and vegetable freshness-keeping packaging bag of Example 1. The package containing broccoli of Example 7 was also stored at 5 ° C. for 5 days, then stored at 40 ° C. for 2 days, and the changes in quality such as the appearance and smell of broccoli were traced. In addition, a good condition was maintained for a total of 7 days.

  After the packaging bodies of Examples 1 to 9 were stored under the above conditions for 7 days, mold spores adhering to the surface of green soybean or broccoli were observed with a microscope, and no mold spores were germinated. On the other hand, a plurality of mold colonies adhered to the green soybeans stored using the fruit and vegetable freshness-keeping packaging bags of Comparative Examples 1 to 3, although not visible to the naked eye.

  In addition, the elongated opening provided in the fruit and vegetable freshness-keeping packaging bag of Comparative Example 3 was prepared using a technique of tearing starting from the peripheral edge of the main hole with both ends of the film. The length from the periphery of the part was very long. As a result, in the same method as in Comparative Example 3, a bag that could withstand commercial production could not be obtained.

Claims (11)

A fruit and vegetable freshness-keeping packaging bag composed of a perforated synthetic resin film,
The porous synthetic resin film is provided with one or more through holes,
The through-hole is a fruit and vegetable freshness-keeping packaging that satisfies the following conditions, and the maximum thickness of the perforated synthetic resin film in an area within 10 mm from the outer periphery of the through-hole on the outer surface of the fruit and vegetable freshness-holding packaging bag And Tmax, and the minimum thickness is Tmin, the ratio of the maximum thickness to the minimum thickness Tmax / Tmin is 1.05 or more and 8.00 or less .
Conditions: Cut out the test piece of the perforated synthetic resin film into a rectangular shape of 20 cm × 25 cm so as to include one through hole, and place it at the center of the short side of the test piece under room temperature (25 ° C.) condition. at the time of applying a load of 9N 60 minutes, the opening area of the through hole before loading the pre-yn heavy S _0, the opening area of the through hole after preloading the yn heavy was S ₁ At this time, the dimensional stability calculated by the following formula (1) is 6.0% or more and 9.0% or less.
Formula: Dimensional stability ratio [%] = {(S ₁ / S ₀ ) −1} × 100 (1)   2. The fruit and vegetables according to claim 1, wherein the planar shape of the through-hole includes a main hole and a long opening extending from the peripheral edge of the main hole to the outside of the main hole. A freshness-keeping packaging bag. The fruit and vegetables freshness-keeping packaging bag according to claim 1 or 2 , wherein the maximum thickness Tmax of the perforated synthetic resin film is 16 µm or more and 400 µm or less. The fruit and vegetables freshness-keeping packaging bag according to any one of claims 1 to 3 , wherein the minimum thickness Tmin of the porous synthetic resin film is 15 µm or more and 60 µm or less. 35 ° C. of the perforated synthetic resin film, the oxygen permeation amount in 90% RH is, any ^{100000mL / 100g · m 2 · day} · atm or more ^{800000mL / 100g · m 2 · day} · atm or less claims 1 to 4 The fruit and vegetable freshness-keeping packaging bag according to claim 1. The fruit and vegetables according to any one of claims 1 to 5 , wherein the perforated synthetic resin film has a water vapor permeability at 40 ° C and 90% RH of 4 g / m ² · day to 400 g / m ² · day. A freshness-keeping packaging bag. A package containing fruits and vegetables formed by sealing fruits and vegetables with the freshness-keeping packaging bag for fruits and vegetables according to any one of claims 1 to 6 . Of the vegetables and fruits containing packaging material, the packaging body area of the vegetables and fruits fresh-keeping packaging bag per the fresh produce 100g is 100 cm ² or more 5000 cm ² or less, vegetables and fruits containing packaging body according to claim 7. The package containing fruits and vegetables according to claim 7 or 8 , wherein the oxygen concentration in the package containing fruits and vegetables is 0.1% or more and less than 19% before the package containing fruits and vegetables is opened. The package containing fruits and vegetables according to any one of claims 7 to 9 , wherein a weight reduction rate of the entire package including fruits and vegetables is 0.05% by weight or more and less than 1% by weight per day. A method for maintaining the freshness of fruits and vegetables by packaging fruits and vegetables using the packaging bag for maintaining freshness of fruits and vegetables according to any one of claims 1 to 6 .