JP2849586B2 - Synthetic resin film for maintaining freshness of fruits and vegetables and method for maintaining freshness - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fruit and vegetable freshness retaining material and a freshness retaining method, and more particularly to a synthetic resin film containing hinokitiol and the like, and a packaging material for keeping fruit and vegetable freshness using the same. And a method for maintaining freshness.

In the present specification, fruits and vegetables are fruits and fruits (hereinafter simply referred to as fruits) after harvesting, fruits and vegetables such as vegetables, and fruits and vegetables such as root vegetables, beans, potatoes, cereals and the like, which have been subjected to processing such as peeling, Alternatively, it is a herbaceous product obtained by subjecting a fruit or vegetable to a processing such as cutting or subdividing, such as cut vegetables, or a vegetable or a fruit subjected to a slight drying or dehydration operation, or the like.

[Conventional technology]

Many fruits and vegetables continue to ripen after harvest,
Causes various changes, such as changes in the aroma and color of the fruit and softening of the pulp. Among these, fruits and vegetables, depending on their type, do not wait for ripening and can be harvested when they are quite immature if they have grown to a certain stage. Some can be served as food.

The ripening phenomenon of such fruits and vegetables after harvest is called ripening, and this phenomenon is used to transport fruits and vegetables.
Storage and the like are performed, and generally, the purpose of utilization is achieved by preventing or promoting the ripening action as necessary. Conventional techniques for preventing the ripening effect of fruits and vegetables and extending the transport and storage period include the phenomenon of increased respiratory action (climacteric and
A method for adsorbing ethylene causing rise is known (for example, JP-A-56-88752).

Further, as conventional techniques for preventing corrosion due to the growth of microorganisms (for example, mold) after harvesting, fruits and vegetables are washed with saline or chlorine water, fruits and vegetables are prepared with alcohol preparations, and antibacterial substances are synthesized with synthetic resin films and nonwoven fabrics. It has been proposed to store the product coated on the surface together in a cardboard box or a bag made of synthetic resin, or to spray a bactericide directly into a mist.

In addition, the growth of microorganisms is suppressed, and a safe substance is adsorbed on an appropriate article, for example, various packaging materials and adhesives, and is brought into contact with the food surface, or the food is coated or coated with such packaging material. A method of transporting is proposed, and it is disclosed that hinokitiol, hinokitiol salts and clathrates thereof give good results as the substance (for example, JP-A-61-108359).

[Problems to be solved by the invention]

As described above, in order to maintain the freshness of fruits and vegetables, studies have been made on adsorption of ethylene and moisture and prevention of corrosion. However, in such a conventional technique, there are complicated operations such as providing a post-harvest washing step and putting fruits and vegetables in a cardboard box or a synthetic resin bag together with an alcohol preparation or the like. In addition, surface-coated products have a large loss of antibacterial substances and cannot control the sustained-release property freely.Moreover, due to the washing process and the formulation used, there are problems with the quality deterioration and safety of fruits and vegetables. In addition, it was difficult to maintain the freshness of fruits, vegetables and the like during storage and transportation.

Therefore, the present inventors, by suppressing the increase in the respiratory action of fruits and vegetables, while sufficiently preventing the ripening action, to significantly improve the effect of suppressing the growth of microorganisms, extending the storage period, Furthermore, a packaging material capable of minimizing post-harvest pretreatment steps, eliminating the complexity of packaging work, and improving the commercial value of fruits and vegetables, a synthetic resin film as the material, and We worked diligently to develop a preservation method.

[Means for solving the problem and its operation]

As a result, they have found that a synthetic resin film containing hinokitiol or the like can achieve the above object. The present invention has been completed based on such findings.

That is, the present invention contains one or more compounds of hinokitiol, a salt thereof, and a cyclodextrin inclusion compound containing them, and a carbon dioxide / oxygen permeability ratio is 2 to 2.
It is intended to provide a synthetic resin film for maintaining freshness of fruits and vegetables, characterized in that it is 10 and a method for maintaining freshness of fruits and vegetables, characterized by packaging or coating fruits and vegetables using this synthetic resin film.

As described above, the synthetic resin film of the present invention contains one or more of hinokitiol, a salt thereof, and a cyclodextrin inclusion compound containing the same.
The content of these compounds is the film 1 m ² per 0.1 to 2000
mg (in terms of hinokitiol), preferably 20-300 mg. When the content is less than 0.1 mg / m ² , the antibacterial effect is not sufficiently exhibited. However, even if the content exceeds 2000 mg / m ² , no improvement in the effect corresponding to the content is observed.

As a material for producing the synthetic resin film of the present invention,
Although various polymers or copolymers can be used, olefin polymers are particularly preferable. Here, examples of olefin polymers include homopolymers of α-olefins having 12 or less carbon atoms, such as ethylene, propylene, 1-butene, 1-hexene, and 3-methyl-1-pentene; -Random or block copolymers of olefins,
Or an olefin as a main component, and vinyl acetate, acrylic acid, methacrylic acid, alkyl acrylate,
There is a copolymer with an alkyl methacrylate or the like.
Specifically, for example, high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-propylene rubber, ethylene-butene-1 rubber, ethylene-propylene-1-butene random Copolymer, ethylene-propylene block copolymer, ethylene-propylene-1
-Butene block copolymer, ethylene-vinyl acetate copolymer, propylene-1-butene random copolymer, ethylene-acrylic acid copolymer, and metal salt of ethylene-methacrylic acid copolymer. You may have these individually or in mixture of 2 or more types.

In addition, a styrene polymer, 1,2-polybutadiene, or the like may be used in addition to the olefin polymer described above.

In order to produce the synthetic resin film of the present invention, one or more compounds (hinokitiols) of hinokitiol, salts of hinokitiol and cyclodextrin inclusion compounds containing these are blended to form the olefin polymer as described above. What is necessary is just to shape into a film. The hinokitiols may be blended in the monomer mixture before the production of the olefin polymer, or may be blended after the production of the polymer and before the film formation. The film can be formed by any conventionally known method, for example, by extrusion molding such as inflation molding or T-die molding.

In the present invention, the hinokitiols are
Usually, in addition to hinokitiol itself, its salts (including complex salts, double salts, etc.) or cyclodextrin clathrate compounds containing hinokitiol or its salts are mentioned.

The synthetic resin film of the present invention is preferably composed of the olefin polymer as described above, and the carbon dioxide (CO ₂ ) / oxygen gas (O ₂ ) permeability ratio of the film is in the range of 2 to 10. It is preferably, and more preferably 3 to 7. CO ₂ /
When the O ₂ ratio is less than 2, when the fruits and vegetables are packaged in a film, the CO ₂ concentration inside the packaging becomes high, and the fruits and vegetables have difficulty breathing.

Such a transmittance ratio can be adjusted by appropriately selecting the film thickness. The film thickness depends on the type of synthetic resin used, but is generally 5 to 200 μm,
Preferably, the thickness is 12 to 120 μm.

The melt flow rate of the synthetic resin used in the present invention (MF
R, JIS-K7210) are not particularly limited, but for example, MFR values
It is preferably about 0.1 to 10 g / 10 minutes.

Hinokitiol, its salts, and cyclodextrin inclusion compounds containing them suppress the generation and growth of microorganisms, so that synthetic resin films containing them are effective in maintaining the freshness of fruits and vegetables. In addition, although the mechanism of the freshness maintaining action of this film has not yet been completely elucidated, one of the causes is a sustained release effect. In other words, in the case where hinokitiols are coated on the film surface, hinokitiol is present on the film surface, so that volatilization proceeds during storage and work, and blooming phenomenon easily occurs, which is affected by the environment inside the packaging. It is difficult to control the sustained release of hinokitiol, and it is difficult to change it depending on the purpose of use. However, in the present invention, hinokitiols are dispersed in the film,
Sustained release control is possible by changing the resin or the resin composition according to the purpose of use.

The synthetic resin film for maintaining freshness of fruits and vegetables of the present invention is effective for maintaining freshness of fruits and vegetables as described above.

The synthetic resin film for maintaining freshness of fruits and vegetables of the present invention can be applied to fruits and vegetables in various forms, and there is no particular limitation on the form of use. For example, it can be used as a sheet or bag, or as a cardboard box lining. For example, when used in the form of a bag, the bottom of a tubular film is sealed, fruits and vegetables are packed in a bag sealed on three sides of a sheet-like film, or fruits and vegetables are put in a bag with a back seal and bottom seal. Thus, the freshness of the fruits and vegetables can be maintained for a long time by sealing the entrance. Here, “seal” means a heat seal (for example,
Heat seal in a broad sense including impulse seal, high frequency seal, ultrasonic seal, etc.), adhesion (meaning in a broad sense including sticking by a method of bonding using components other than film or hot melt) , A method of sticking with a tape, a method of stopping with a rubber, and the like. Any method may be used as long as the film can be joined in a state of little air leakage or no air leakage.

If fruits and vegetables are packaged using the synthetic resin film for maintaining fruits and vegetables freshness of the present invention, the freshness of fruits and vegetables can be maintained for a long period of time.

When using the synthetic resin film for keeping freshness of the present invention,
In the case where ethylene is generated from the fruits and vegetables or the amount of water generated is large, the freshness maintaining effect of the fruits and vegetables is further improved by using a conventionally known ethylene absorbent or water absorbent.

〔Example〕

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Example 1 A linear low-density polyethylene L-LDPE containing 0.5% by weight of hinokitiol (density 0.924 g / cm ³ ; measured by JIS-K7112; MFR = 0.8 / 10 minutes; JIS-K7210); Use), using an extruder with a diameter of 50 mm, extrusion temperature 190
270mm, thickness 15μ under the condition of ℃, take-off speed 35m / min
m of an inflation film was formed. The hinokitiol content was measured by measuring the volatilization rate of hinokitiol and the amount thereof by a weight reduction method by sampling 1 m ² of the above film.
The measurement conditions were a temperature of 23 ° C. and a humidity of 60%. As a result, 3
It was observed volatilization of the film 1m ² per 34.5mg after day.

Next, after heat-sealing one of the films,
The pieces were cut to a length of 0 mm, 1 kg of cherry was added, and a storage test was performed at room temperature. As a result, even after the elapse of 7 days, there was no generation of mold, decayed fruit, and browning of the pattern, and there was no atrophy on the fruit surface, the fruit was fresh, the appearance was good, and the commercial value was sufficient.

Example 2 A film was prepared in the same manner as in Example except that hinokitiol was contained in an amount of 1.0% by weight. The volatilization of hinokitiol was 69.0 mg / m ^{2 of} film.

As a result of preservation in the same manner as in Example 1, seven days have passed. However, no generation of mold, no rotting fruit, no browning of the pattern, no fruit surface atrophy, freshness, good appearance, and commercial value. It was enough.

Example 3 Freshly harvested broccoli (60 strains) were divided into 5 groups of 12 strains each, and the 12 strains were placed in a film produced in the same manner as in Example 1, the mouth was folded and packed in a large cardboard box.

Comparative Example 1 A storage test was performed under the same conditions as in Example 1 using a bag manufactured under the same conditions as in Example 1 except that hinokitiol was not contained. As a result of storage, after 7 days, the occurrence of mold was observed. 65% of the whole was fresh without any atrophy on the fruit surface, good in appearance, and sufficient in commercial value, but 10% of rotten fruits and 25% of pattern browning
Also reached.

Comparative Example 2 1 kg of cherry was put in a cardboard box and stored. As a result, after 2 days, the atrophy of the fruit surface was 10%, but no rotten fruit was seen yet, and the pattern browning was 10%. Was. 3
On the day, the occurrence of mold was observed, and after 7 days, the occurrence of mold was observed in almost the entire area. The rotting fruit was 30% and the pattern browning was 80%, indicating no commercial value.

Comparative Example 3 1 kg of cherry was put in a cardboard box, and hinokitiol 5
After spraying 20 ml of a 00 ppm aqueous solution in the form of a mist, storage was performed. After 2 days, no mold had developed and no decayed fruit had yet been seen, but the pattern browning was 10% and the fruit surface had begun to shrink. After 7 days, no mold had yet appeared and no spoilage had occurred, but the pattern browning was 100% and had no commercial value.

Comparative Example 4 12 strains of broccoli were packed in a large cardboard box, closed with a gum tape and subjected to a storage test.

Comparative Example 5 Twelve strains of broccoli were placed in a high-pressure polyethylene bag having a thickness of 0.03 mm, the mouth was folded, and packed in a cardboard box in the same manner as in Comparative Example 4 to perform a storage test.

Comparative Example 6 Twelve strains of broccoli were put into a film produced in the same manner as in Comparative Example 1, the mouth was folded, and the same as in Comparative Example 4, packed in a cardboard box and subjected to a storage test.

Comparative Example 7 After packing 12 broccoli strains in a cardboard box, SRH-1
00 (a film containing 100 mg / m ² of hinokitiol in 0.15 mm thick rayon paper) was placed on broccoli, and a cardboard box was sealed with a gum tape to perform a storage test.

The thickness, gas permeability and permeability ratio of the films of Examples 1 and 2 were measured. The results are shown in Table 1.

Further, Example 3 and Comparative Examples 4 to 7 were subjected to vacuum pre-cooling to lower the product temperature to 10 ° C, and then stored at room temperature (20 to 23 ° C). Observations were made daily and checked for mold, odor and yellowing. The results are shown in Table 2.

As is clear from the results of the storage tests of cherry and broccoli in each of the above examples, the results of the examples of the present invention exhibited a higher freshness retaining effect than the results of the comparative examples.

〔The invention's effect〕

INDUSTRIAL APPLICABILITY The synthetic resin film for maintaining freshness of fruits and vegetables of the present invention has an appropriate carbon dioxide / oxygen gas permeability ratio and thus has an action of suppressing the respiration of fruits and vegetables, and contains hinokitiol uniformly dispersed in the film, so that it is released gradually. And its microbial growth inhibitory action lasts for a long time.

In addition, the synthetic resin film for maintaining freshness of fruits and vegetables of the present invention sufficiently prevents the ripening effect by suppressing the increase in respiratory action of fruits and vegetables, dramatically improves the effect of suppressing the growth of microorganisms, and shortens the storage period. It can be extended to minimize post-harvest pre-treatment steps, simplify packaging and increase the commercial value of fruits and vegetables.

Therefore, the present invention is expected to be widely used as an effective technique for maintaining the freshness of fruits and vegetables.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C08L 101: 00 (72) Inventor Ritsutaro Fukasawa 4-19-10 Shozuzawa, Itabashi-ku, Tokyo Seiwakasei Co., Ltd. (56) Reference Document JP-A 1-245058 (JP, A) JP-A 2-196863 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08K 5/00-13/08 B65D 65 / 38-65/46 B65D 85 / 34,85 / 50

Claims (4)

(57) [Claims] 1. Freshness retention of fruits and vegetables, characterized by containing one or more compounds of hinokitiol, salts thereof and cyclodextrin inclusion compounds containing them, and having a carbon dioxide / oxygen permeability ratio of 2 to 10. For synthetic resin film. 2. A hinokitiol, synthetic resin film of claim 1 wherein one or more compounds of its salts and cyclodextrin inclusion compounds containing them, the film 1 m ² per 0.1 to 2000 mg (hinokitiol equivalent) containing. 3. The synthetic resin film according to claim 1, wherein the synthetic resin is an olefin polymer. 4. A method for preserving freshness of fruits and vegetables, comprising packaging or covering fruits and vegetables using the synthetic resin film according to claim 1.