JP2634526B2 - Package containing fruits and vegetables - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging bag for keeping fruits and vegetables fresh by maintaining respiration under an appropriate oxygen atmosphere even after the fruits and vegetables are packaged in a packaging bag of polymer film. It is about. More specifically, while maintaining an oxygen atmosphere that prevents anaerobic respiration in the low oxygen state caused by the respiratory action of fruits and vegetables, furthermore, suppresses deterioration in quality caused by oxidation by oxygen, and packs water vapor generated by respiratory action. The present invention relates to a packaging bag which is taken out of a bag and maintains conditions for preventing soft rot caused by water droplets.

[0002]

2. Description of the Related Art Fruits and vegetables maintain their respiratory action even after being harvested. For this reason, it is necessary to prevent deterioration of the quality of fruits and vegetables during storage and distribution after harvest and until eating.
In addition, as the production form of fruits and vegetables, intensive cultivation by factories,
Distribution to consumer areas, sales at supermarkets, etc. are taking the same distribution form as industrial products, and various distribution channels are taken from production to sales, so pack packaging is used to protect fruits and vegetables (products). It is becoming necessary. Under these circumstances, the fruits and vegetables currently on the market are simply distributed and sold in packaging bags made of unstretched polypropylene or the like. These packaging bags used for fruits and vegetables are non-porous, and most of them are sealed or deaerated. For this reason, the fruits and vegetables are exposed to an anaerobic atmosphere after being packaged, and are forced to undergo anaerobic respiration.The sugars in the fruits and vegetables are digested by this anaerobic respiration, and alcohol and When the bag was opened due to generation of aldehyde and the like, most of the odors were off-flavor.

[0003] Further, regarding plant materials such as general vegetables,
As a method for supplying oxygen and maintaining freshness, a method using a perforated film has been proposed (JP-A-62-148247).
And Japanese Patent Application Laid-Open No. 63-119647), these films have an opening area ratio of 2 × 10 ^-2 to 2 × 10%.
The oxygen in the bag is almost the same as the atmospheric state even when wrapped with these films, which is the same as the open state. With these open packagings, the amount of oxygen in the air is equivalent to the amount of oxygen in the air. There is a problem that the respiratory action becomes active and the fruits and vegetables grow further, and furthermore, there is a problem that the vegetables are easily withered due to evaporation of water. Therefore, a packaging material or a packaging method that retains the original taste of fruits and vegetables and can be served on a table while keeping it fresh has not yet been discovered.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to form a desirable oxygen concentration atmosphere for maintaining the freshness of fruits and vegetables for a long period of time, and to supply products which do not generate off-flavors, do not brown, and do not wilter. It is a result of intensive research, providing the minimum amount of oxygen necessary for the survival of fruits and vegetables, keeping the fruits and vegetables in a hibernating state, so as to suppress browning and growth, which are disorders of high oxygen content, and Another object of the present invention is to provide a package containing fruits and vegetables for supplying fresh fruits and vegetables by preventing soft rot caused by water vapor (water droplets) generated by breathing of fruits and vegetables.

[0005]

According to the present invention, there is provided a package containing fruits and vegetables comprising a polymer film in which fruits and vegetables are sealed, wherein the package comprises (A) a perforated polymer film and (B) a non-porous polymer film. (A),
(B) at least one of the film characteristics has a water vapor transmission rate measured at 25 ° C. and a relative humidity of 75% of 50 to 800 gm ⁻² d ^{−1 based} on the effective surface area of the package;
It is preferably from 50 to 500 gm ^-2 d ^-1 , wherein (A)
Is 3 × 1 with respect to the effective surface area of the package.
That is 0 ^-6 ~7 × 10 ^-4% related to vegetables and fruits containing packaging material, characterized. The fruits and vegetables are vegetables, legumes,
It includes mushrooms, fruits, flowers and fresh flowers. The present invention will be described more specifically. As a first aspect,
The porous polymer film (A) has substantially no water vapor permeability, and the nonporous polymer film (B)
C. and a relative humidity of 75%, the water vapor transmission rate is 50 to 800 gm based on the effective surface area of the package.
^The package containing fruits and vegetables according to claim ^1, which has ^-2 d ^-1 , preferably 50 to 500 gm ^-2 d ^-1 . In a second embodiment, the porous polymer film (A) and the nonporous polymer film (B) are both
The water vapor transmission rate measured under the conditions of 5 ° C. and 75% relative humidity is 50 to 800 g based on the effective surface area of the package.
The fruit and vegetable-containing package according to claim ^1, which has m ^-2 d ^-1 , preferably 50 to 500 gm ^-2 d ^-1 . According to a third aspect, the porous polymer film of (A) has a water vapor transmission rate measured at 25 ° C. and a relative humidity of 75%, which is 50 to 800 gm ^{− based} on the effective surface area of the package. ² d ^-1 , preferably 50 to 500 g
The fruit-and-vegetable package according to claim ^1, which has m ^-2 d ^-1 and wherein the nonporous polymer film (B) has substantially no water vapor permeability. . The most typical packaging bag used in the present invention is a bag using the film (A) on one side and a film using the film (B) on the other side. The present invention also includes a mode in which fruits and vegetables are put in a commonly used tray in the packaging bag used in the present invention. In particular, when used in such a form, it is preferable that the packaging bag portion corresponding to the upper side of the tray is the film (B) described above and is a heat-shrinkable film because the finish of the package is good. Even if the bag appears close to the tray, there is a distribution point between the top and bottom of the tray that is much larger than the opening area, so this does not usually cause a problem, but if there is a possibility that it may occur May be provided with one to four notches in the peripheral portion of the tray.

[0006] The porous polymer film used in the present invention may be any film as long as it can be used for packaging of fruits and vegetables, but it is generally possible to use polypropylene, polyethylene, polyvinyl chloride, or the like. Saponified ethylene-vinyl acetate copolymer (trade name: EVAL)
And the like, but other than these, such as films of polyamide, polyester, polycarbonate and the like, and further may be composite films of these, and further, those having a sealant layer provided on the surface of these films may be used. There is no problem even if the film is antifogged. These films may be stretched or unstretched. The thickness of these films is usually 20 to 40 μm. further,
These films may be transparent or opaque, and there is no problem even if the film is printed on the surface.

The opening area ratio of the packaging bag using the perforated polymer film of the present invention is determined by the amount of fruits and vegetables to be packed, and the opening area ratio is 3 × 10 ^{-6 to} 7 × 10 ^-4.
%. The reason for this is to maintain the amount of oxygen and carbon dioxide in the packaging bag under conditions suitable for maintaining the freshness of the fruits and vegetables. According to the experimental results of the present inventors, the oxygen concentration was 3% or more and 15% or less. Desirably, the opening area ratio for satisfying these conditions is 3 × 10 ^{−6 to} 7 × 1.
It is in the range of ^0-4 %. If the open area ratio is 3 × 10 ⁻⁶ % or less, the fruits and vegetables become anoxic during the distribution process due to the respiratory action after packaging, and start anaerobic respiration, generating an unpleasant odor. On the other hand, if the open area ratio is 7 × 10 ⁻⁴ % or more, the amount of oxygen in the packaging bag becomes too large, and under the influence of this oxygen, wounds caused in the production, packaging or distribution process of the fruits and vegetables However, oxygen causes a browning phenomenon, and since the amount of oxygen is large, the respiratory action of the fruits and vegetables is activated, and there is a problem that the fruits and vegetables grow more than necessary. Accordingly, the aperture area ratio of the perforated film used as a packaging bag for fruits and vegetables is 3 × 10 ^{−6 to} 7 × 10 ^−4.
%, Preferably 4 × 10 ⁻⁶ to 8
× 10 ^-5 %, particularly preferably 6 × 10 ^{-6 to} 5 × 10 ^-5
% Is more effective.

The average diameter of the pores in the perforated polymer film is desirably as small as possible, generally about 20 to 150 μm, preferably 30 to 100 μm. It is desirable that the pore size be as small as possible.
If it is less than μm, the productivity of the perforated polymer film decreases.
If the average pore size is 150 μm or more, the number of holes required to obtain an appropriate ratio of the open area decreases, and the quality accuracy of maintaining the freshness becomes uneasy. The shape of the hole may be any shape such as a circle, a square or a triangle, and any shape may be used as long as the average diameter in the major axis direction is 150 μm or less. More desirable.

The number of holes per bag of the perforated polymer film used in the packaging bag containing fruits and vegetables is calculated from the ratio of the open area and the average hole diameter. Holes may be blocked due to adhesion of contents or external conditions such as the attachment of a price list. To ensure freshness, a plurality of holes are preferable, and more than 5 holes per bag, It is desirable that the degree of influence per hole be 20% or less. Also, as a packaging bag for fruits and vegetables,
Bags in the form of a three-sided seal bag, four-sided seal bag or gusset bag can be used without any problem.Furthermore, trays, cups and the like are filled with fruits and vegetables, and these are packed in a packaging bag. Good.

Examples of the water vapor permeable polymer of the present invention include regenerated cellulose, acetyl cellulose, homopolymers of polyolefins, copolymers with vinyl acetate or methyl acrylate, polyesters and polyamides. The films may be further laminated and / or include one or more layers, such as a heat seal layer. These films may be stretched or unstretched. If it is desired to reduce the permeability to water vapor, it is generally preferred to coat the film. Suitable materials for this purpose are known in the art.
In this way, a water vapor transmission rate of 50 to 800 gm ^-2 d ^-1 can be achieved. In the present invention, the film having substantially no water vapor permeability has a water vapor permeability (thickness of 30 μm).
m) means 50 gm ^-2 d ^-1 or less, such as polyvinylidene chloride, rubber hydrochloride, polyethylene, polypropylene, polyvinyl chloride and the like. It should be noted that a perforated film having only the perforations in the present invention cannot achieve the target water vapor transmission rate by only the perforations.
In order to allow water vapor to permeate only through the holes, the open area ratio must be as large as 0.1 to 3.0%. However, with such a hole area ratio, it is impossible to control the gas such as oxygen gas, and the oxygen gas becomes substantially free.

In order to maintain the freshness of vegetables and the like, it is a matter of course that temperature control in the distribution process and at stores is an important point, and the respiration of fruits and vegetables naturally depends on these temperatures. The respiratory volume increases as it becomes, but the present invention assumes that these temperatures are 5 to 15 ° C.

[0012]

EXAMPLES Example 1 A film having a thickness of 35 μm and an inner size of 200 mm × 240.
A mm square seal bag, the film on one surface thereof opened 95 pieces of holes of flat <br/> Hitoshiana径30 [mu] m, the effective surface area of the bag
On the other hand, the opening area ratio was set to 7.0 × 10 ⁻⁵ %.
The other side of the film was made of stretched polypropylene and had no pores. A stretched nylon film having a water vapor transmission rate of about 100 gm ⁻² d ⁻¹ was used , and a bag was formed by part coat adhesion . This bag is filled with 250 g of sprouts that have been washed and drained (the effective surface area in the bag is 200 × 240 × 2 = 96,000 m)
m Ru ² der), stored at 10 ° C., the freshness of the 3 days and 5 days after the observed odor occurrence, browning and greening situation. As a result, good results were obtained in each case. Gas concentration in the packaging bag in <br/> is, O ₂ after 3 days 11% CO ₂ 7%,
After 5 days, O ₂ was 7% and CO ₂ was 12%.

Example 2 A film having a thickness of 35 μm and an inner size of 200 mm × 230.
A mm square seal bag, the film on one surface thereof opened nine is 60μm pores flat <br/> Hitoshiana径, the effective surface area of the bag
On the other hand, the opening area ratio was adjusted to 2.8 × 10 ⁻⁵ %.
Stretched polypropylene film (with heat seal layer on inner surface)
Consists has one), the other surface of the film is ethylene vinyl acetate copolymer of the water vapor transmission rate 150 gm ^-2 d ^-1 saponification
Object film was used. This bag, a green soybeans and 200g filled, and stored at a temperature 5 ° C., to observe its freshness odor occurrence after 3 days and 7 days, and brown Henjo situation. As a result, good results were obtained in each case. The gas concentration in the packaging bag is 12% O ₂ after 3 days, 5% CO ₂ , and O ₂ after 7 days.
Was 12% and CO ₂ was 5%.

Example 3 A film having a thickness of 25 μm and an inner size of 150 mm × 200
A mm square seal bag, a film of one surface consists playback cellulose water <br/> vapor transmission rate 200 gm ^-2 d ^-1, the other surface of the film is opened 55 holes of flat Hitoshiana径80 [mu] m, The open area ratio to the effective surface area of the bag is 4.6 × 1
With full <br/> Irumu consisting oriented polypropylene which was set to be 0 ^-4%, and bag-making part-coat adhesion. 100 g of mushrooms were put in a tray made of paper in this bag, sealed and packaged, and stored at 5 ° C. Three days and five days later, freshness was observed for odor generation, browning and water wetness. As a result, good results were obtained in each case. Packaging
O ₂ gas concentration after 3 days in the bag is 16% CO ₂ 4%
After 5 days, O ₂ was 17% and CO ₂ was 3%.

Example 4 A film having a thickness of 25 μm and an inner size of 150 mm × 200
A mm square seal bag, the film on one surface thereof with a stretched polyamide film of water <br/> vapor transmission rate 150 gm ^-2 d ^-1, the other surface of the film flat Hitoshiana径is 50μm pores 5
Open two pieces , and the ratio of the open area to the effective surface area of the bag is 1.
Using a stretched polypropylene film ^{adjusted to} 7 × 10 ⁻⁴ %, a bag was formed by part coat adhesion . 100 g of shimeji mushrooms were placed in a tray of expanded polystyrene, sealed and packed at 5 ° C., and odor generation, browning and water-wetting were observed after 3 and 5 days. As a result, good results were obtained in each case. The gas concentration in the packaging bag was 15% for O ₂ after 3 days, 5% for CO ₂ , and 12% for O ₂ after 5 days.
% And CO ₂ were 9%.

Comparative Example 1 A non-porous packaging bag made of unstretched polypropylene having an inner size of 200 mm × 240 mm and a thickness of 20 μm was filled with 250 g of the same sprouts as used in Example 1, and the same as in Example 1. Similarly, freshness after 3 days and 5 days was examined. As a result, after 3 days, a bad smell was generated. Gas concentration in the packaging bag is 3
O ₂ 0% after day, CO ₂ is 21%, O ₂ after 5 days 0
% And CO ₂ were 25%.

[0017] "Comparative Example 2" a packaging bag of a similar size as in Example 1, using a 35μm cast polypropylene having a thickness, aperture area ratio 7.4 ×
Using a packaging bag in which 90 holes having an average pore diameter of 100 μm were formed so as to be 10 ⁻⁴ %, 250 g of the same sprouts as those used in Example 1 were filled, and freshness after 3 days and 5 days as in Example 1 was measured. Examined. As a result, no bad odor was generated, but after 3 days, browning and greening had occurred. Packaging
O ₂ gas concentration after 3 days in the bag is 18% CO ₂ 2%
After 5 days, O ₂ was 15% and CO ₂ was 4%.

Comparative Example 3 200 g of green soybean used in Example 2 was filled in a non-porous packaging bag made of polyethylene having an inner size of 200 mm × 230 mm and a thickness of 50 μm, and stored at a temperature of 5 ° C. The freshness after 3 days and 7 days was examined in the same manner as in Example 2. As a result, after 3 days, a bad smell was generated. 0% gas concentration in the packaging bag is O ₂ after 3 days, CO ₂ is 21%, O ₂ 0% after 7 days,
CO ₂ was 28%.

[0019] "Comparative Example 4" a packaging bag of a similar size as in Example 2, using a stretched polypropylene film of 35μm thickness, the apertures area ratio
Using a packaging bag in which 60 holes having an average pore size of 60 μm were opened so that the density became 1.8 × 10 ⁻⁴ %, 200 g of green soybeans similar to those used in Example 2 were filled and stored at a temperature of 5 ° C. As in 2, the freshness after 3 days and 7 days was examined. As a result, browning of the epidermis was progressing. The gas concentration in the packaging bag was 19% O ₂ after 3 days, 1% CO ₂ , 20% O ₂ after 7 days,
CO ₂ was 1%.

Comparative Example 5 A non-porous packaging bag made of a stretched polypropylene film having an inner size of 150 mm × 200 mm, a thickness of 25 μm, and a water vapor transmission rate of 6 gm ⁻² d ^{−1 was} prepared in the same manner as in Example 3. 100 g of mushrooms were put in a paper tray, sealed and packaged, stored at 5 ° C. in the same manner as in Example 3, and the freshness after 3 days and 5 days was examined. As a result, after 3 days, odor and water wetting had occurred. O ₂ 0% after the gas concentration in the packaging bag 3 days,
CO ₂ is 23%, O ₂ 0% after 5 days, CO ₂ was 38%.

Comparative Example 6 A packaging bag having the same size as that of Example 4 and a thickness of 25 μm
m, using the stretched polyamide film of the water vapor transmission rate 150 gm ^-2 d ^-1, five opened packaging bag a mean pore diameter of 50μm pores to open hole area ratio is 1.6 × 10 ^-5% using, 100 g of the same shimeji used in Example 4 was placed in a tray of expanded polystyrene, sealed and packaged, stored at 5 ° C. in the same manner as in Example 4, and the freshness after 3 days and 5 days was examined. As a result, after 3 days, a bad smell was generated. After 3 days, the gas concentration in the packaging bag was 3% for O ₂ , 17% for CO ₂ ,
After ₂ days, O ₂ was 0% and CO ₂ was 25%.

<< Comparative Example 7 >> The same thickness as in Example 3 with a thickness of 25 μm and a water vapor transmission rate of 200 g
using regenerated cellulose m ^-2 d ^-1, aperture area ratio 4.
Two pores having an average pore diameter of 120 μm were set to 3 × 10 ⁻³ %.
Using a packaging bag opened by 30 pieces, 100 g of the same mushroom as used in Example 3 was put in a paper tray, sealed and packaged, and stored at 5 ° C. as in Example 3, and the freshness after 3 days and 5 days was examined. Was. As a result, browning had progressed after 3 days. The gas concentration inside the packaging bag is 20% O ₂ after 3 days,
CO ₂ is 0%, O ₂ 20% after 5 days, CO ₂ was 0%.

[0023]

Industrial Applicability The package of the present invention prevents odors generated by anaerobic respiration of fruits and vegetables, and also prevents sugar digestion due to anaerobic respiration, while preventing browning, growth and ripening due to excessive oxygen. It can be stored for a long time while keeping the freshness. In particular, keeping fresh fruits and vegetables, such as mushrooms, flowers, beans, etc., with strong breathing, removes moisture and oxygen gas,
It is necessary to balance the control of carbon dioxide gas, and the present invention has been fully satisfied. The perforated film requires one more opening step than the non-perforated film, so the cost increases and the rejection rate due to the additional step increases. In the present invention, by replacing a part of the perforated film with a non-perforated film, the amount of the perforated film used can be reduced without lowering the function as a packaging bag.

Claims (7)

(57) [Claims] 1. A package containing fruits and vegetables comprising a polymer film in which fruits and vegetables are sealed, wherein the package comprises (A) a perforated polymer film and (B) a non-porous polymer film. ) And (B) have a film permeability of 50 to 800 gm ^-2 d ^{-1 based} on the effective surface area of the package, as measured at 25 ° C and 75% relative humidity. The open area ratio of (A) is 3 × 10 ^{−6 to} 7 × with respect to the effective surface area of the package.
A package containing fruits and vegetables, which is 10 ^-4 %. 2. The porous polymer film of (A) has substantially no water vapor permeability, and the non-porous polymer film of (B) was measured at 25 ° C. and 75% relative humidity. The water vapor transmission rate is 50 based on the effective surface area of the package.
The packaged product containing fruits and vegetables according to claim ^1, which has a weight of from -800 gm ^-2 d ^-1 . 3. The water vapor transmission rate of both the porous polymer film (A) and the non-porous polymer film (B) measured at 25 ° C. and a relative humidity of 75% is equal to that of the package. 2. The package containing fruits and vegetables according to claim ^1, which has 50 to 800 gm ^-2 d ^{-1 based} on the effective surface area. 4. The porous polymer film of (A), wherein
The water vapor transmission rate measured under the conditions of 5 ° C. and 75% relative humidity is 50 to 800 g based on the effective surface area of the package.
The packaged product with fruits and vegetables according to claim ^1, which has m ^- 2d- ¹ and wherein the non-porous polymer film (B) has substantially no water vapor permeability. 5. The package containing fruits and vegetables according to claim 1, wherein the perforated polymer film (A) has pores having an average pore diameter of 20 to 150 μm. 6. The package with fruits and vegetables according to claim 1, wherein a plurality of said holes are provided. 7. The package containing fruits and vegetables according to claim 1, wherein the polymer film (B) is heat-shrinkable.