JP2000279085A - Freshness-keeping agent for vegetable and fruit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a freshness-keeping agent for keeping the freshness of vegetables and fruits under transportation or preservation over a long period. SOLUTION: This freshness-keeping agent is obtained by laminating a moisture-absorbing and releasing layer obtained by attaching a moisture- absorbing and releasing agent to a substrate selected from nonwoven fabric, woven fabric, paper, porous body, net-like material, film and sheet to integrate them, and holding a metabolic gas regulator, and an air-permeable buffer layer selected from a flexible or semi-rigid porous body and a fibrous material laminate. The moisture-absorbing and releasing agent is a water-absorbing resin, moisture-absorbing and releasing inorganic particles or a mixture of the water- absorbing resin and the moisture-absorbing and releasing inorganic particles, and the metabolic gas regulator is a generation inhibitor or remover of ethylene gas or aldehyde gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a freshness preserving material for preserving freshness of fruits and vegetables.

[0002]

2. Description of the Related Art Consumers need to obtain perishable fruits and vegetables such as peaches and melons as fresh as possible.
Keeping vegetables and fruits fresh for a long period of time due to the need to maintain the shape and freshness during transportation due to separation and remoteness of production and consumption areas, as well as requests to extend the storage period at stores and consumers Technology is required. The biggest causes of loss of freshness of fruits and vegetables are the loss of water caused by poor environmental humidity and rot due to excessive moisture, and especially in the case of fruits, metabolic gas generated from fruits, especially maturation by ethylene gas and aldehyde gas, Acceleration of aging. Therefore, the biggest problem of keeping freshness is to maintain the humidity of the environment of fruits and vegetables in an appropriate range for a long time and to regulate the metabolic gas generated by fruits and vegetables (suppression of metabolic gas generation, decomposition and adsorption of generated gas). . In addition, damage due to vibration and compression during transportation significantly reduces the value of the fruits and vegetables. Therefore, simultaneously preventing such damage is also a performance required for a freshness maintaining sheet material.

[0003] As a means for responding to this problem, a method of maintaining an appropriate humidity by using a highly water-absorbing material or a humidity control material has been used. In addition, metabolic gas decomposers and adsorbents are used to adsorb or decompose ethylene gas emitted by fruits and vegetables. Japanese Patent Application Laid-Open No. 3-65135 discloses a sheet material for keeping freshness, and the sheet material is coated on one side with a water-permeable film on one side and the other with a water-permeable film or water-impermeable film. By heat sealing, it is used as a freshness-preserving sheet material to be stored in a closed space together with fruits and vegetables. This sheet material for keeping freshness has a freshness keeping agent having a function of adsorbing generated gas, a water-absorbing polymer, and a humidity control agent coexisting with a water-permeable sheet material such as a nonwoven fabric. However, this sheet is used in a storage space for fruits and vegetables in order to control the preservation environment of the fruits and vegetables. If the sheet is stored in a moisture absorbing state in contact with the fruits and vegetables, the moisture causes rot instead. In addition, it does not have a function to protect fruits and vegetables from vibration and pressure applied during transportation.

[0004]

SUMMARY OF THE INVENTION The present invention relates to the production of perishable fruits and vegetables such as fruits, vegetables and flowers, especially peaches and melons.
Provided is a freshness maintaining material for maintaining freshness during transportation and storage for a long period of time.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a method comprising forming a base material selected from a nonwoven fabric, a woven fabric, a paper, a porous material, a net-like material, a film, and a sheet with a moisture absorbing / releasing agent attached to the base material; The present invention relates to a freshness retaining material for fruits and vegetables, which is formed by laminating a moisture absorbing / releasing layer holding a gas regulator and a breathable buffer layer selected from a soft or semi-hard porous body or a fibrous material laminate. More specifically, the present invention relates to a freshness preserving material in which the moisture absorbing / releasing agent is a highly water-absorbing resin, a moisture absorbing / releasing inorganic particle, or a mixture of a highly water absorbing resin and a moisture absorbing / releasing inorganic particle. More specifically, the present invention relates to the above-mentioned freshness retaining material, wherein the metabolic gas regulator is an ethylene gas or aldehyde gas generation inhibitor or a remover. Furthermore, the present invention relates to the above-mentioned freshness retaining material, wherein a waterproof layer is further laminated on the outside of the substrate.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The freshness retaining material of the present invention is characterized by a moisture absorbing / releasing layer in which a moisture absorbing / releasing agent is integrally attached to a substrate and a metabolic gas regulator is retained, and a breathable buffering material. The following effects can be obtained when the fruits and vegetables are held on the freshness holding material, or are packaged with the freshness holding material and stored or transported because of the configuration in which the layers are stacked.
In other words, the action of the metabolic gas regulator suppresses the generation of metabolic gas such as ethylene gas and aldehyde gas, or removes the metabolic gas, thereby suppressing the ripening and aging of the fruits and vegetables, and at the same time as the air-permeable buffer material layer. The combination of the moisture release layers keeps the fruits and vegetables under appropriate humidity conditions without directly contacting the excess moisture. Furthermore, since the fruits and vegetables are stored in contact with the air-permeable buffer material layer, the fruits and vegetables can be prevented from growing, and have an action of protecting the fruits and vegetables from external force such as vibration and compression.

[0007] The air-permeable cushioning material layer is in direct contact with the fruits and vegetables, and can be made of a material that not only allows good permeation of air and humidity but also protects the fruits and vegetables placed thereon from external force by a buffering action. Specifically, the air-permeable cushioning material layer is selected from a soft or semi-hard porous material or a fibrous material laminate. Of course, a multilayer laminate selected from these may be used. Preferably, it is a flexible porous body. Specific examples include open-cell synthetic resin foams such as flexible polyurethane foams and polyethylene foams.

The moisture absorbing / releasing layer absorbs or releases moisture in the environment, preferably moisture and moisture, and retains the moisture absorbing / releasing agent capable of stably maintaining the humidity and moisture conditions of the environment. And a metabolic gas regulator contained in one or both of them. As a material that can be used for the base material, a nonwoven fabric, a woven fabric, paper, a porous body, a net, a film, a sheet, and the like are preferable. Particularly preferred are a nonwoven fabric and a porous body. In another embodiment, a waterproof film or sheet laminated on a nonwoven fabric or a porous body together with a waterproof film or sheet is used as a base material, and the waterproof film or the like is used on the outside, that is, on the opposite side of the air-permeable cushioning material layer. It is possible to prevent undesired drying of the moisture in the moisture-releasing layer and prevent contamination by moisture contained in the moisture-releasing layer. Specific examples of the moisture absorbing / releasing agent include a material containing a highly water-absorbing resin or moisture-releasing / absorbing inorganic particles, or both as main components.

The water-absorbent resin is a water-soluble resin partially crosslinked to make it water-insoluble, and is a starch-sodium acrylate graft polymer, a hydrolyzate of a starch-acrylonitrile graft polymer, a partially crosslinked starch-polystyrene. (Meth) Acrylic acid copolymer, partially cross-linked starch-polymethyl methacrylate hydrolyzate and starch-such as their salts-graft polymerization system, or methyl methacrylate-vinyl acetate copolymer hydrolyzate A typical example is a crosslinked synthetic resin type. However, as long as the water absorption is 1.5 times or more, and preferably 2 times or more, its own weight, the resin is not limited to the above, and any superabsorbent resin can be used. Many superabsorbent resins are commercially available, and these commercially available products can be used in the present invention. Examples of commercially available products include “Sunwet” (manufactured by Sanyo Chemical Industries),
Examples include “AQUALIC” (manufactured by Nippon Shokubai Chemical Co., Ltd.) and “Acogel” (manufactured by Mitsui Cytec).

Examples of the hygroscopic inorganic particles that can be used as the hygroscopic layer include silica gel and zeolite. The adhesion of the powdery superabsorbent resin or the hygroscopic inorganic fine particles to the substrate can be performed, for example, by the following method: 1) Adhering to the substrate together with the binder in a state of being dispersed in the binder resin. 2) A binder resin is applied to a substrate and sprayed from above before drying the resin. 3) Sprayed together with a low melting point resin powder such as an olefin resin and heat-treated.

As can be understood from the above description, in the manufacturing process, the moisture absorbing / releasing agent is first adhered to the substrate to form a moisture absorbing / releasing layer, and then the moisture absorbing / releasing layer is laminated with the air-permeable buffer layer. It is preferable that the moisture absorbing / releasing agent be finally laminated between the air-permeable cushioning material layer and the base material, or if it exists in a state of being fixed to the base material, the state in the intermediate step. Is not limited.

[0012] The moisture absorbing / releasing agent may be entirely or partially deposited on the substrate. When emphasis is placed on moisture absorption and water retention, it is preferable to attach the entire surface,
When importance is placed on the air permeability, it is preferable to partially adhere. Examples of the form of the partial attachment include a dot shape, a band shape, and a lattice shape. The size of the dots and the width in the case of a grid or a band are not particularly limited, but it is preferable that the dots be uniform at any part in terms of uniformity. The attachment in the form of dots can be performed by a rotary screen, a flat screen, a transfer method, or the like.

The freshness retaining material of the present invention is used in such a manner that fruits and vegetables come into contact with the air-permeable buffer layer of the freshness retaining material as described later. Waterproof film or sheet is not laminated on the outside of the base material to prevent moisture held in the layer from wetting other packaging materials that come into contact with the base material through the base material and to speed drying of the moisture absorbing and releasing material. In the case of a holding material, it is desirable to further wrap the outside with a waterproof material.

The freshness preserving material of the present invention is used for suppressing or eliminating the generation of ethylene gas or aldehyde gas, which is a metabolic gas emitted by fruits and vegetables, in order to prevent undesired rapid maturation and aging of the fruits and vegetables during storage and transportation. Use a metabolic gas regulator together. The metabolic gas regulator can be held in either or both of the gas-permeable buffer layer and the moisture absorbing / releasing layer, but is preferably retained in the moisture absorbing / releasing layer.
Examples of the metabolic gas regulator include hinokitiol, hiba oil, potassium permanganate adsorbed on natural zeolite, activated carbon and the like reacted with bromate,
Porous activated carbon alone or the like can be used. Particularly preferred ones have an action of suppressing the generation of metabolic gas, such as hinokitiol and hiba oil. Metabolic gas regulators can also be used in sustained release form encapsulated as microcapsules.

The freshness retaining material of the present invention can retain one or more agents such as an antibacterial agent and a fungicide in combination. As a result, the environment of the fruits and vegetables can be maintained more favorably, and the freshness can be maintained for a longer period. These agents can be retained in the moisture absorbing and releasing layer or the breathable cushioning layer or both.

In order to maintain the freshness of fruits and vegetables or transport them over long distances using the freshness retaining material of the present invention, it is only necessary to package the fruits and vegetables on the breathable cushioning layer. When the fruits and vegetables are stored or transported in such a state, the moisture absorbing and releasing layer absorbs the excess moisture generated by the fruits and vegetables, and the fruits and vegetables do not come into direct contact with the absorbing and releasing layer in the water absorbing state, so that the excess moisture is not absorbed. Contact is prevented and the humidity condition is kept constant.
In addition, the metabolic gas regulator suppresses the generation of metabolite gas such as ethylene gas and aldehyde gas from the fruits and vegetables, or adsorbs or decomposes and removes the generated gas, so that the excessive ripening of the fruits and vegetables can be suppressed. Furthermore, the fruits and vegetables can be protected from damage due to external vibration, compression and the like by the breathable cushioning material layer holding the fruits and vegetables.

[0017]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples.
This will be described more specifically. Example 1 Polyester nonwoven fabric as a substrate (basis weight 20 g /
hinokitiol 5 g / m ² , heat-sealed product)
m ^2, and a superabsorbent resin (a resin obtained by adding a polyethylene glycol diglycidyl ether as a cross-linking agent to an acrylate resin) is applied on one side of the resin to an amount of 15 g / m ^2.
Then, a moisture-absorbing / desorbing layer was formed by adhering in a dot shape (a dot having a diameter of 1 mm and a density of 117 points per square inch) by a rotary screen. The thus obtained moisture absorbing / releasing layer and a breathable cushioning layer made of a flexible polyurethane foam (apparent density: 14 kg / cm ³ ; thickness: 2 mm) are laminated in such a manner that a highly water-absorbing resin is sandwiched inside, thereby forming a frame. By lamination, a freshness retaining material for fruits and vegetables was produced.

Example 2 Highly water-absorbing resin (acrylic acid) obtained by mixing sustained-release microcapsules of hinokitiol (encapsulating material: polyurethane, particle size: 1 to 10 μm) with the same polyester nonwoven fabric substrate used in Example 1 Resin obtained by adding polyethylene glycol diglycidyl ether as a crosslinking agent to salt resin)
20 g / m ² (including 5 g of microcapsules)
/ M ²⁾ and allowed to adhere to the entire fiber surface so as, this more flexible polyurethane foam on the coating layer (apparent density 14kg / cm ^3, similar to a thickness of 2 mm) breathable cushioning layer as in Example 1 To obtain a freshness retaining material for fruits and vegetables.

Example 3 Acrylic resin "Nippol L" containing 15% by weight of ethylene gas adsorbent "Morshibon" (trade name, manufactured by Takeda Pharmaceutical Co., Ltd.) on the surface of the same polyester nonwoven fabric substrate as used in Example 1 × 851c '; (trade name by Nippon Zeon Co., Ltd.) "Morushibon". the coating is 5 g / m ^2, further polyethylene glycol diglycidyl as a crosslinking agent to the superabsorbent resin (acrylate resin in this one-sided 15 g / resin)
m ² by a rotary screen to form dots (dots having a diameter of 1 mm per square inch).
(A density of 17 points) to form a moisture absorbing / releasing layer.
The thus obtained moisture absorbing / releasing layer and a breathable cushioning layer made of a flexible polyurethane foam (apparent density: 14 kg / cm ³ , thickness: 2 mm) are laminated in such a manner that a highly water-absorbing resin is sandwiched inside, and a frame is formed. By lamination, a freshness retaining material for fruits and vegetables was produced.

[Fruit Transport Test] A transport test of ripe peaches was carried out using the freshness retaining material for fruits and vegetables prepared in Examples 1 to 3. The transport test method is as follows. Ripe peach: Shimizu white peach with no green at the bottom of the fruit, and usually has a shelf life of about 2 days. Transportation mode: Using a cardboard box for 4 kg, fruits are wrapped in Japanese paper and covered with a mesh-shaped fruit cap made of expanded polystyrene in a single layer. Wood was arranged. Transport temperature: ambient temperature (28 ° C) Transport distance and duration: Okayama ⇒ Osaka round trip (2 days) Okayama ⇒ Kyoto round trip (3 days) Okayama ⇒ Tokyo round trip (4 days). For comparison, the materials of Comparative Examples 1 and 2 were used instead of the freshness retaining materials of Examples 1 to 3.

Comparative Example 1 The flexible polyurethane foam used in Example 1 as a breathable cushioning layer was used alone.

Comparative Example 2 A highly water-absorbent resin (trade name “AQUALIC CA”; manufactured by Nippon Shokubai Chemical Co., Ltd.) was dispersed in an amount of 15 g / m ² between two pulp sheets (having a basis weight of 30 g / m ² ). The laminate was held, and a polyethylene sheet was sandwiched between pulp sheets at the peripheral edge and heat-sealed to produce a laminated sheet.

Table 1 shows the state of fruit deterioration caused by transportation.

[Table 1]

[0024]

By using the freshness retaining material of the present invention, fruits and vegetables can be stored and transported for a long period of time while maintaining freshness.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jun Konaka 2-4-1, Kutaro-cho, Chuo-ku, Osaka-shi, Osaka Kurashiki Spinning Co., Ltd. Osaka head office F-term (reference) 2B100 AA01 BA07 BA08 BD02 BD16 HA19 HA20 4B069 HA11 KA05 KA08 KB07 KC07 KC09 KC30 KD04 KD07

Claims (7)

[Claims] 1. A base material selected from a non-woven fabric, a woven fabric, a paper, a porous body, a net-like material, a film, and a sheet, wherein a moisture absorbing / releasing agent is attached and integrated, and a metabolic gas regulator is held. A freshness maintaining material for fruits and vegetables, comprising a moisture absorbing / releasing layer and a breathable cushioning material layer selected from a soft or semi-hard porous material or a fibrous material laminate. 2. The freshness retaining material according to claim 1, wherein the moisture absorbing / releasing agent is entirely or partially adhered on the substrate. 3. The freshness retaining material according to claim 2, wherein the partial adhesion is in a dot shape, a band shape, or a lattice shape. 4. The freshness preserving material according to claim 1, wherein the moisture absorbing / releasing agent is a superabsorbent resin, a moisture absorbing / releasing inorganic particle, or a mixture of the superabsorbent resin and the moisture absorbing / releasing inorganic particle. 5. The freshness preserving material according to claim 4, wherein the hygroscopic inorganic particles are selected from silica gel and zeolite. 6. The metabolic gas regulator is an ethylene gas or aldehyde gas production inhibitor or a remover.
The material for maintaining freshness described in 1. 7. The freshness retaining material according to claim 1, wherein a waterproof layer is further laminated on the outside of the substrate.