JPS6328572B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for keeping red meat fresh. For example, fresh red fish, particularly tuna and bonito, are bright red in color when fresh, but as they lose their freshness, they turn brown and lose their commercial value. As described above, fresh fish can generally only be stored for 2 to 3 days even if it is refrigerated, and it has been impossible to store it for a longer period of time. For this reason, when selling fresh fish, retailers purchased the fish frozen from the market, thawed it, and sold it in the amount they wanted to sell that day. For this reason, it is difficult to improve the distribution system, and pre-packaging is either impossible or limited to areas where it can be delivered within a few hours. Also, unsold items that day cannot be sold as products the next day. Fresh fish, especially tuna, usually takes on a bright red color in the air. This is mainly because myoglobin, a pigment in meat, comes into contact with oxygen and becomes oxymyoglobin. Over time, the iron contained in myoglobin oxidizes to produce metmyoglobin, which takes on a brown color. On the other hand, when oxidation of the porphyrin ring in the structure of myoglobin occurs, the flesh becomes green in color. In order to preserve the redness of fresh fish and raw meat, there has traditionally been a method of packaging raw meat in a high oxygen concentration atmosphere, such as 70% oxygen concentration and 30% carbon dioxide gas concentration. Unfortunately, this method was not widely used because of the high gas barrier properties required of the packaging material, and the need for large-scale equipment and workability. However, by lowering the oxygen concentration to about 15%, for example, which is slightly lower than the oxygen concentration in the air, which has not been considered in the past as a method of preserving the redness of fresh fish meat, etc., the period until browning occurs can be extended. It has been found. However, in this case, if you create this atmosphere immediately after cutting the meat, myoglobin will not change sufficiently to oxymyoglobin, so
Since the color does not turn bright, it is necessary to leave it for a certain period of time before packaging. In addition, meat such as fresh fish and meat has the problem of leakage of drips (gravy juice). This is because when the temperature of fresh fish, raw meat, etc. is above the freezing point, the water released from the protein tissue comes out, including soluble components. May occur in large quantities due to changes or mechanical forces. Normally, these drips have a very visible appearance, so when fresh fish is used, polypropylene non-woven fabric is placed underneath to absorb them, but sometimes they cannot be absorbed sufficiently. The present invention is a method for preserving the freshness of meat that eliminates these conventional drawbacks by placing a laminated material that absorbs meat drippings between the meat and a drug that absorbs oxygen or generates carbon dioxide gas at the same time as it absorbs oxygen. death,
This is a method for preserving the freshness of meat such as fresh fish, whale meat, and livestock meat, which is characterized by packaging these with packaging material that has a certain oxygen permeability and maintaining the oxygen concentration within the packaging within a range of 5 to 15%. . Further, the present invention is a method for maintaining the freshness of meat, which prevents the transfer of the drug to the meat by providing a laminated material between the drug and the meat. Here, the laminated material 1 provided between the drug and meat used in the present invention is a porous material 2 as shown in FIG.
The resin layer 3 and the liquid-impermeable material 4 are composed of a water-insoluble and water-absorbing resin powder obtained by partially crosslinking a water-soluble resin or a mixture of the resin powder and a porous inorganic powder. An adhesive layer 5 is provided partially within the layer 3. The water-absorbing resin of the resin layer 3 having water-absorbing properties is
A single resin that absorbs water and water-containing solvents, increases volume, and holds it in a gel or solid state, or a mixture of this resin and a porous inorganic powder that absorbs and holds liquid in micropores without changing volume. Consisting of Specifically, water-soluble resins are partially cross-linked to make them water-insoluble, such as starch-sodium acrylate graft polymers, starch-acrylonitrile graft polymer hydrolysates, and partially cross-linked starch-poly(meth). Starch-graft polymers such as acrylic acid copolymers, partially crosslinked starch-polymethyl methacrylate hydrolysates, and salts of the above substances, or hydrolysates of methyl methacrylate-vinyl acetate copolymers. Examples include crosslinked synthetic resins represented by. Further, the porous inorganic powder to be mixed is an inorganic powder having a special shape such as pores or petals, such as zeolite, pearlite calcium silicate, etc. The porous material 2 is a porous fibrous sheet such as paper, nonwoven fabric, or cloth, or a polymer film having pores provided on its entire surface. The liquid-impermeable material 4 is made of a plastic film that is impermeable to liquids and has a relatively high oxygen permeability, such as polyethylene film or polypropylene film. Next, the drugs used in the present invention are ferrous salt-based or ascorbic acid-based drugs, and an example of their composition is shown below. (Composition 1) FeSO ₄・7H ₂ O 30 parts by weight Ca (OH) ₂ 3 〃 NaHCO ₃ 5-15 〃 Na ₂ SO ₃・7H ₂ O 5-15 〃 Activated carbon 1-10 〃 (Composition 2) FeSO ₄・7H ₂ O 30 parts by weight Ca(OH) ₂ 3 〃 CaCO ₃ 5-15 〃 Na ₂ SO ₃・7H ₂ O 5-15 〃 Activated carbon 1-10 〃 (Composition 3) FeSO ₄・7H ₂ O 5-15 by weight Part Ca(OH) ₂ 1-5 〃 NaHCO ₃ 30 〃 Na ₂ CO ₃・10H ₂ O 10-30 〃 Sodium L-ascorbate 30 〃 Activated carbon 1-10 〃 CaCl ₂ 1-5 〃 (Composition 4) FeSO ₄・7H ₂ O 30 parts by weight Ca(OH) ₂ 15 〃 CaSO ₃・1/2H ₂ O 15 〃 Activated carbon 2 〃 Among these, it is better to use a chemical that generates carbon dioxide gas in the present invention because it will reduce the amount of oxygen in the package. This decrease reduces the pressure inside the package, which is preferable because it prevents the package from being deformed and at the same time provides a bacteriostatic effect due to carbon dioxide gas. When this drug is actually used, it is sealed in a packaging material with appropriate air permeability, such as a packaging material made by pasting paper and perforated polyethylene film. Packaging materials used in the present invention include polyvinyl chloride stretch film, polyvinylidene chloride/polyvinyl chloride copolymer stretch film, and those with an oxygen permeability of 3000 to 30000 c.c./m ² / atm / 24 hrs. , stretch packaging using polyethylene stretch film, polyethylene/vinyl acetate copolymer stretch film, sealing in polyethylene, polypropylene, or ethylene/vinyl acetate copolymer film bags, or even wrapping in trays. It is possible to package the package using a polyethylene, polypropylene, or vinyl acetate copolymer film as the lid material. A packaging method using the drug and laminated material as described above is shown in FIGS. 2, 3, and 4. FIG. 2 shows an example in which meat 6 and the drug 8 are placed in a tray 7 via a laminated material 1 and then stretch-wrapped with a packaging material 9 having the above-mentioned oxygen permeability. After housing meat 6, medicine 8, and laminated material 1 in the same manner as in FIG. 2, the opening is hermetically sealed with the packaging material 9. As shown in FIG. 4, after storing the meat 6, medicine 8, and laminated material 1 in the tray 7 in the same way as in FIG.
The entire tray 7 is packaged in a bag shape using the packaging material 9 described above. In this way, in the present invention, the drip-absorbing layer of the laminated material that absorbs drips generated from meat is a water-insoluble and water-absorbent resin powder made by partially crosslinking a water-soluble resin alone, or a porous material containing the resin powder and the drip-absorbing layer. Since the resin is made of a mixture with inorganic powder, it not only can completely absorb the drips generated from meat, but also prevents the migration of the components of oxygen-removing and deoxygenating carbon dioxide gas-generating agents to liquid-impermeable materials. By blocking the meat with a layer, it is possible to maintain good meat color without worrying about food hygiene. Furthermore, by lowering the oxygen concentration or increasing the carbon dioxide concentration at the same time, the proliferation of microorganisms is suppressed and spoilage is inhibited, and since drips are completely absorbed, microbial migration does not occur, which also prevents spoilage. is suppressed. As described above, the method of the present invention has an excellent effect on preserving the redness of meat such as fresh fish, is inexpensive and simple, suppresses the proliferation of microorganisms, etc., and has no hygienic problems and is extremely useful in industry. It is something. Next, examples of the present invention will be described. Example 1 The composition of the agent used to absorb oxygen and generate carbon dioxide gas is as follows. Drug 1: 6.2g of the drug of composition 4 Drug 2: 3.6g of the drug of composition 3 Each of the above drugs was given an air permeability of 400 to 500 seconds/100 c.c.
Filled and sealed in a bag made of Japanese paper and polyethylene film with holes. Place the bag filled with this drug on a styrofoam tray (size 50 x
170×40mm) and laminated material (size 45×170
mm) The non-ventilated material side was placed between the tuna sashimi and the drug. This laminated material consists of unsized processed base paper (60 g/m ² )/resin layer/biaxially oriented polypropylene film (20 μm). The entire contained tray was covered with polyvinyl chloride stretch foam 20μ (oxygen permeability 10000c.c./m ² .
24hrs・ATM, carbon dioxide gas permeability ^40000c.c./m2・
Stretch wrapped for 24hrs/ATM). This is 5
Stored at ~10°C and observed changes in flesh color. For comparison, a sample was prepared that was packaged in the same manner, but without the drug-filled bag. The tuna was obtained frozen from the market and used immediately after thawing (product temperature -3 to 0°C). The results are shown in Table 1.

[Table] Invention 1: Method using drug 1 Invention 2: Method using drug 2 Γ Red was graded in stages, with 5 being bright red and 1 being whitish and brownish. The concentrations of oxygen and carbon dioxide in the package at this time are shown in Table 2. (Units%)

[Table] As shown above, tuna that could only be stored for 1 to 2 days at most in the control group using the conventional packaging method, but with the method of the present invention, it can be stored for 4 to 4 days under the same storage temperature conditions.
It is now possible to store it for up to 5 days. Example 2 In the same manner as in Example 1, 200 g of beef was sliced from block meat and immediately packaged. After being stored at 5 to 10°C for 2 days, the package was left at room temperature (23 to 27°C) to observe any change in meat color. Observed. Further, in the same manner as in Example 1, for comparison purposes, a bag filled with the drug was not inserted, but the bag was packaged in the same manner, and used as a control. The results are shown in Table 3.

[Table] Table 4 shows the oxygen and carbon dioxide concentrations in the packaging at this time.
It is as follows. Oxygen concentration and carbon dioxide concentration in packaging (unit: %)

[Table] Invention 3: Method using drug 1 Invention 4: Drug 2 As described above, by packaging according to the method of the present invention, the meat retains a good color even after being refrigerated for 2 days, and the meat that was previously sliced If we don't sell out within the day,
Although the product value has fallen, this makes it possible to sell the product the next day, which has an extremely large effect on business. In this way, compared to conventional packaging methods, the present invention makes it possible to preserve lean meat for an extremely long period of time, and does not require any special equipment or work; Using a laminated material that can completely absorb carbon dioxide-generating agents and drips from meat, it is easy to package meat with a packaging material that has a certain oxygen permeability, making it easy to produce high-quality lean meat. It is an extremely excellent method for keeping meat fresh for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a laminated material used in the method of the present invention, and FIGS. 2, 3, and 4 are explanatory diagrams showing an example of packaging of the present invention.

Claims (1)

[Scope of Claims] 1. A water-insoluble and water-absorbing resin powder alone or partially cross-linked with a porous material or a water-soluble resin between a drug that absorbs oxygen or simultaneously generates carbon dioxide gas and meat; A resin layer made of a mixture of the resin powder and porous inorganic powder and a laminated material made of a liquid-impermeable material are placed, and these are packaged with a packaging material having a certain oxygen permeability, and the oxygen concentration inside the package is determined. A method for preserving the freshness of meat, characterized by maintaining the freshness of meat in a range of 5 to 15%. 2 The oxygen permeability of the packaging material is 3000 to 30000 c.c./
^2. The method for maintaining the freshness of meat according to claim 1, which is 24 hours/m2/atm.