JPH07102857B2 - Food storage method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a food tray in which food such as meat can be placed, and a food storage method using the food tray.

(Prior art and its problems) Currently, foods such as meat and fish are put in thin-walled food trays and displayed in supermarkets for trade, and these food trays are formed by injection molding. And, the unevenness is also formed on the outer side, and the appearance is poor,
The value of the food to be put inside has been reduced, and the appearance of a food tray with a higher quality is desired.

In order to give a high-class feeling, the food tray may have a large thickness, but if it is formed in this way, it becomes expensive, and when the food tray is disposed of, it is exposed to high temperatures when burning. There is a problem that it will be emitted and damage the combustion furnace etc., and if it is buried in the soil, there will be a problem that pollution will occur further. However, if the food trays are made of wood, the use of wood for disposable food trays will cause further problems in the present time when the heavy use of wood has developed into an international problem. Become.

(Means for Solving the Problem) The present invention, a thick outer film made of a foam of a photodegradable or microbially decomposable resin, and an ultrathin inner film excellent in gas barrier property are polymerized and stamped. Put food such as meat in a box-shaped food tray with an open top that has a concave and convex surface formed by crossing grooves on the inside and a smooth surface on the outside by a molding method, and the top surface is a gas barrier. With a water-soluble resin film, a gas such as nitrogen, carbon dioxide, oxygen, etc. is enclosed in the food tray, and a large number of partitioned bag-shaped spaces containing water-absorbent resin and wasabi are enclosed in the food tray. It is to enclose the frozen regenerator that has.

(Function) The food tray has a double layer of an outer film and an inner film, and since the outer film is thick, the entire food tray has a thick and high-grade shape, and the outer surface is a smooth surface.
The wooden box-like appearance can be enhanced, and an uneven surface is formed on the inner side. By using this uneven surface, cold air or the like can be circulated around the food put inside. In addition, since the inside is an extremely thin film and has excellent gas barrier properties, it is possible to improve the storage stability by enclosing food products and the like inside and sealing them. In addition, most of the food trays are outer films when they are disposed of, and the outer films are photodegradable or microbially degradable, so if they are buried in the soil, they will be decomposed well to prevent pollution. It never happens.

Also, by putting food such as meat in the food tray, covering it with a gas barrier film and sealing it, and enclosing a gas such as nitrogen, carbon dioxide, oxygen, etc. inside, the inside of the meat is prevented from being oxidized by this gas filling. The effect of preventing discoloration and the like can be obtained, and the function of maintaining freshness can be improved.

Also, by enclosing the regenerator in the food tray, the cold air generated from the regenerator circulates well through the uneven surface inside the food tray to keep it cool in the food tray, and the meat inside. Can maintain good freshness.

(Example) Hereinafter, the Example of this invention is described based on drawing.

FIG. 1 is a perspective configuration view of a food tray of the present invention. The food tray 1 is formed in a box shape with a bottom whose upper part is opened, and an inner surface of the food tray 1 has grooves 2 crossing in the vertical and horizontal directions. Are formed, and the groove 2 makes the inner surface uneven. The outer peripheral surface is formed as a plate-like smooth surface.

As shown in the enlarged sectional view of FIG. 2, this food tray 1 is composed of a double film layer, and is formed by superposing an extremely thin inner film 1b on the inner side of the outer film 1a.

The outer film 1a is a photodegradable or microbial degradable resin film, for example, polyvinyl alcohol (PVA),
It is formed of biodegradable plastics such as polyethylene glycol, polyester, polyurethane, polyamino acid, etc., and is a biodegradable copolymer of aliphatic polyester and polyamide, and copolymer of aliphatic polyester and aromatic polyester. It may be formed of a polymer or the like. Further, it may be formed from a water-soluble polymer of a polysaccharide such as a plant-based, microbial-based or semi-synthetic cellulose derivative, guar derivative, alginic acid derivative, starch derivative and the like.

Further, the inner film 1b is formed of a resin film having excellent gas barrier properties, for example, a film composed of acrylonitrile as a main component, a graft copolymer of methyl acrylate and butadiene is used,
In addition, a film having a gas barrier property, such as a polyvinyl alcohol, an ethylene / vinyl alcohol copolymer, a saponified ethylene / vinyl acetate copolymer, an amorphous nylon, a biaxially stretched nylon, or the like can be used.

The inner film 1b is extremely thin compared to the thickness of the outer film 1a, and the outer film 1a is formed thick so as to give a high-class feeling, and in order to further increase the thickness, the outer film 1a is formed. The above-mentioned biodegradable resin can be used as a foam, and the wall thickness can be further increased. For example, a halogenated hydrocarbon, butane, pentane or the like can be used as a foaming agent.

The food tray 1 is co-extruded by a combination of a known field block method and a multi-manifold method, whereby the outer film 1a and the inner film 1b are extruded as a single film from the extruder as a double layer, In the extruded state, the inner film 1b is compression-molded from the upper surface of the inner film 1b by a press mold by a stamping molding method, and the depth of the concave-convex groove 2 is appropriately adjusted by adjusting the compression pressure during the stamping molding. Formed.

As described above, the food tray 1 of the present invention comprises a double layer of an extremely thick outer film 1a and an extremely thin inner film 1b, the outer surface of the outer film 1a is formed into a smooth surface, and the groove 2 is formed inside. Therefore, when the food tray 1 is viewed from the outside, a sense of quality like a thick, smooth wooden box is generated, and the quality of the food to be put inside can be improved.
Also, since most of it is the outer film 1a, when it is disposed of, it is biodegradable and can be satisfactorily decomposed in the soil, etc. by burying it in the soil, etc., causing the conventional pollution. And the processing is easy.

In addition, the food tray 1 formed in this way is used to
As shown in the side cross-sectional view of the figure, for example, meat 4 can be put in the inside thereof, and the film 3 can be attached to the upper opening of the food tray 1 by heat sealing or the like to seal the inside of the food tray 1. As the sealing film 3, it is possible to use a film having an excellent gas barrier property similar to the inner film 1b described above. When the film 3 is sealed, nitrogen gas, carbon dioxide gas, oxygen gas, etc. can be sealed in the food tray 1.

For example, when the meat 4 is put in the food tray 1, oxygen and carbon dioxide gas are used as the gas to be filled, and the ratio of carbon dioxide gas of 20 to 70 to oxygen 80 can be filled. The discoloration of the meat 4 can be effectively prevented. or,
When putting fish in the inside, carbon dioxide gas is used for fatty fish.
It is possible to fill the gas with the ratio of nitrogen gas 40 to 60, and to fill the gas with the ratio of nitrogen gas 30 to 40 carbon dioxide in other fish. Further, when ham and sausage are put inside, carbon dioxide gas of 20 to 70 can be filled with nitrogen gas 80 to enhance the bacteriostatic effect and prevent discoloration. In addition, the gas to be filled can be variously changed and used according to the food to be put in the food tray 1. For example, nitrogen gas is put in the case of shavings, carbon dioxide gas is put in the case of sandwiches and bento, and cheese is added. ， Kirimochi, Anatto, Castella,
In the case of Baumkuchen and white rice, the bacteriostatic effect can be enhanced by filling carbon dioxide gas. or,
Green tea, coffee, cocoa, powdered juice, seaweed wakame,
Dried shiitake mushrooms, freeze-dried products, oil confectionery, bean confectionery, peanuts,
When edible oil, tofu, fried oil, donut, konjac refined powder, natto, etc. are put inside, nitrogen gas is mainly filled to improve discoloration and antioxidant effect.

In addition, the food tray 1 is filled with various gases in this manner to maintain freshness, and the food tray 1 is provided with a fourth gas.
A cool storage sheet 5 as shown in the figure is put in, and the inside of the food tray 1 can be kept cool by the cool air emitted from the cool storage sheet 5 to further improve the freshness retention function. Inner film 1b with excellent gas barrier properties
Since the above-mentioned gas and cold air do not escape to the outside, a good freshness retention function can be achieved, and the cool air and gas pass through the vertical and horizontal grooves 2 formed on the inner surface. Circulates and diffuses satisfactorily in the inside, and cold air and gas wrap the entire circumference of the food such as meat 4 contained therein, so that better freshness can be maintained, and the food can be stored for a long time. Such food tray 1 can also be used for cold storage transportation of foods produced and collected in foreign countries into Japan, and the foods inside can be kept fresh during transportation.

The details of the cold storage sheet 5 are shown in FIGS. 4 and 5.

In the figure, the packaging sheet 5 is formed by partitioning a large number of bag-shaped spaces 5a into grooves 5b in the vertical and horizontal directions to form a single sheet, which is shown in the sectional view of FIG. As described above, the water-permeable sheets S ₁ and S ₂ forming the front surface portion and the back surface portion are attached to each other at regular intervals to form the groove portion 5b,
A bag-shaped space 5a having a considerable space is formed between the grooves 5b, 5b, and a considerable amount of granular water-absorbent resin 6 is enclosed in the bag-shaped space 5a. The one shown in FIG. 5 is constructed by further adhering the waterproof sheet 7 to the surface of the water permeable sheet S ₁ on one side. The water permeable sheets S ₁ and S ₂ are made of a sheet material that allows water and air to pass through, and examples of such sheet material include fibrous materials such as paper, non-woven fabric, woven fabric, knitted fabric, and cotton. A sheet etc. are mentioned.
The waterproof sheet 7 is made of a water-impermeable sheet material, and is made of a plastic sheet such as polyethylene, polypropylene or polyvinyl chloride. or,
Aluminum foil may be used instead of the plastic sheet. Also, the water-absorbent resin 6 enclosed in the bag-shaped space 5a
Are, for example, starch-acrylonitrile graft polymer hydrolysates, cellulose-copolymers of cross-linking agents, such as hydrolysates of acrylolithyl graft polymers, such as cross-linked polyacrylamide and its hydrolysates. , Cross-linked sulfonated polyethylene, cross-linked poplar, JP
52-14689 and JP-A-52-27455, saponified vinyl ester-unsaturated carboxylic acid copolymer, crosslinked polyacrylic acid salt and acrylic acid-acrylic acid ester copolymer, crosslinked Examples thereof include isobutylene-maleic anhydride copolymer, crosslinked polyethylene oxide and the like. Further, a polymer having self-crosslinking property, for example, self-crosslinking polyacrylic acid, a resin described in JP-B-54-30710, or a polymer having at least a hydroxyl group and a carboxylate group in the molecule, for example, JP-B-54- The resin described in 37994 may be used. A water-absorbing resin obtained by polymerizing starch or cellulose with a water-soluble monomer and / or a monomer that becomes water-soluble by hydrolysis and a cross-linking agent as essential components and performing hydrolysis if necessary. May be. The above water-absorbent resin may be of one type, or two or more types may be used, and the water-absorbing performance is preferably about 20 to 2000 g / g. Further, regarding the shape of the water-absorbent resin 2, There is no particular limitation, and any shape such as powder, particles, flakes, and fibers may be used.

In addition, powder wasabi is enclosed together with the water absorbent resin 6 in the bag-shaped space 5a. This powdered wasabi is a blend of horseradish and western mustard, for example.
In contrast, a blend of 1 mustard or 1 horseradish and 9 mustard must be blended. In addition, instead of western wasabi, wasabi can be used, and instead of western mustard, Japanese mustard can be used.

In addition to these powdered horseradish and mustard powder, a vitamin C agent may be further mixed in the bag-shaped space 5a. That is, this vitamin C agent is a powder or crystal of L-ascorbic acid, sodium L-ascorbate, L-ascorbic acid with a glycerin fatty acid ester film, sodium L-ascorbate with a glycerin fatty acid ester film, and the like. The C agent is preferably one whose surface is coated with a film material such as ethyl cellulose or silicon. Further, in addition to coating, the vitamin C agent may be dissolved in ethyl alcohol and absorbed into a porous material such as silica gel, siloid, or alumina to be granulated.

When using the packaging sheet 5 configured in this way, the packaging sheet 5 is immersed in tap water or pure water in advance to allow water to permeate into the bag-shaped space 5a from the side of the water permeable sheet to Water is absorbed by the water absorbent resin 6. The water-absorbent resin 6 becomes a spherical shape that expands as it absorbs water. In this state, remove the packaging sheet 5 from the water and
If you leave it for about a minute, the free water and the adhered water will be cut off. In this state, put the packaging sheet 5 in the freezer,
Freeze instantly below ℃.

The completely frozen product can be taken out from the freezer and put in the food tray 1 for transportation. As described above, since it is instantly frozen at −30 ° C. or lower, the activation of sinigrin in the powdered wasabi in the bag-shaped space 5a is in a continuous state, and cold air from the water absorbent resin 6 is transported during transportation. The water absorbent resin 6 is gradually emitted to exert a cold storage effect and can keep meat or the like cool. As the temperature gradually rises, water is evaporated from the water-absorbent resin 6. The generated water acts on the sinigrin in the powdered wasabi to hydrolyze the sinigrin, and this hydrolysis causes the allyl which is a entanglement component to be removed. Oil (also called allyl isothiocyanate or allyl isocyanate) is generated, and this allyl mustard oil exhibits antibacterial properties. Traditionally, this allyl mustard oil is cholera bacterium, typhoid bacterium, Escherichia coli, streptococcus pneumoniae, diphtheria bacterium. , Antibacterial properties against Mycobacterium tuberculosis, etc. have been confirmed, and it has been confirmed that it inhibits the glycolytic action and respiration of Anisakis larvae and is effective in the prevention of anixosis, etc. It can be suppressed well and the effect of maintaining freshness can be enhanced.

When the temperature rises further, the aforementioned vitamin C agent gradually flows out from the porous inorganic material and acts on the powdered wasabi,
It acts on myrosinase, which is a hydrolase in the powdered wasabi, and the SH group of myrosinase protein is reduced by the vitamin C agent, and this myrosinase is activated. By the activation of myrosinase, myrosinase strongly acts on sinigrin, The hydrolysis of sinigrin is promoted, and as described above, the allyl mustard oil is satisfactorily produced from the sinigrin, and the allyl mustard oil firmly prevents the generation of bacteria and the like.

Thus, the freshness is maintained by the cold air emitted from the water-absorbent resin 6 at the first stage during transportation, and the freshness-retaining function is gradually maintained by the antibacterial action of the allyl mustard oil emitted from the powdered wasabi. it can. Moreover, since the above-mentioned powdered wasabi and vitamin C are completely harmless to the human body, they are highly safe and exhibit extremely safe antibacterial activity against foods.

If the food tray 1 is formed of foamed P / P (foamed with calcium carbonate) or crystallized polyester and is given heat resistance, the food 4 is placed in the food tray 1. Put the cold storage sheet 5 on top of it
It is possible to heat the food tray 1 placed in a placing state, wrapped with the film 3 in the microwave oven at home, etc., as it is in the microwave oven while keeping the food 4 sealed in the microwave oven. During the heating, the moisture in the cold storage sheet 5 is released into the food tray 1, and when the food is heated in the microwave oven, there is a problem that the food becomes dehydrated and hardened. By the water supplied from 5, the food is steamed in the food tray 1 to be in a more suitable water state, so that the food can be cooked satisfactorily.

(Effects of the Invention) The present invention is a stamping mold forming method in which a thick outer film made of a foam of a photodegradable or microbial degradable resin is polymerized with an extremely thin inner film excellent in gas barrier property. Put the food such as meat in the bottomed box-shaped food tray that has an open surface on the inside and a smooth surface on the outside and a smooth surface on the outside, and use the gas barrier resin film on the top surface. Frozen cold storage that covers and encloses gas such as nitrogen, carbon dioxide, oxygen, etc. in the food tray, and has a large number of compartmented bag-shaped spaces enclosing water-absorbent resin and wasabi in the food tray By encapsulating the agent, it is possible to form a thick food tray with a thick outer film, and since the outer film is biodegradable, it can be disposed of satisfactorily without causing pollution. Na I can. In addition, when a food product or the like is put inside and is used for transportation, the inner film exerts a gas barrier property, and the food product inside can be satisfactorily kept cool without letting the gas and cold air inside escape to the outside. Further, since the uneven surface is formed on the inner side, the uneven surface allows the gas and the cold air to circulate evenly in the inside, and the meat and the like in the inside can be satisfactorily kept fresh. Also, by putting food such as meat in the food tray and covering the upper surface with the gas barrier resin film, and enclosing gas such as nitrogen, carbon dioxide, oxygen in the food tray, nitrogen gas, carbon dioxide, oxygen, etc. The above gas exerts a bacteriostatic effect, a discoloration preventing effect, and the like, and the food inside can be excellently kept fresh. Further, by enclosing the frozen regenerator in the food tray, cold air is gradually emitted from the water-absorbent resin during transportation, so that meat and the like can be kept cool. Also, as the temperature gradually rises, water evaporation from the water-absorbent resin occurs, but this generated water acts on sinigrin in the powdered wasabi, the sinigrin is hydrolyzed, and the allyl mustard oil that is a entanglement component by hydrolysis. (Ally referred to as allyl isothiocyanate or allyl isocyanate) is generated, and it is possible to satisfactorily suppress the generation of bacteria and mold, and to enhance the freshness-retaining effect.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a perspective view of a food tray, FIG. 2 is an enlarged view of a partial cross-section of FIG. 1, and FIG. 3 shows a case where meat is put inside. Side view of the state of use, No. 4
The figure is a block diagram of the cold storage sheet, and FIG. 5 is an enlarged cross-sectional view of the cold storage sheet of FIG. 1 ... Food tray, 1a ... Outer film 1b ... Inner film, 2 ... Groove 3 ... Film, 4 ... Meat (food) 5 ... Cold storage sheet

Claims (1)

[Claims] 1. A thick outer film made of a foam of a photodegradable or microbial decomposable resin and an extremely thin inner film excellent in gas barrier property are polymerized and crossed inside by a stamping molding method. In the uneven surface by the groove like a groove, put food such as meat in a bottomed box-shaped food tray having an open top formed by forming an outer smooth surface, and cover the upper surface with a gas barrier resin film, Nitrogen in the food tray,
A food characterized by enclosing a gas such as carbon dioxide gas and oxygen, and enclosing a frozen regenerator having a large number of compartmented bag-shaped spaces enclosing a water-absorbent resin and powder wasabi in a food tray. Preservation method.