JPH0825257B2 - Food packaging sheet - Google Patents

Description

TECHNICAL FIELD The present invention relates to a food packaging sheet which is effective for keeping the freshness of fresh food products and storing and storing salt dried products.

(Prior art and its problems) Conventionally, it is said that the maturity of fruits and vegetables is promoted when ethylene gas acts, and an example of using activated carbon as a freshness-retaining material for such fruits and vegetables (see Japanese Patent Publication No. 55-50451), zeolite and Otani. A low molecular gas adsorption oxidation catalyst material obtained by pulverizing, using a porous material such as stone, as a base material, adding a trace amount of metal oxide, kneading and sintering, and performing oxygen treatment using electromagnetic waves or ozone. However, it is still not sufficient in terms of activity and activity retention period, although an example of using (see JP-A-61-93835) has been reported.

(Object of the Invention) Therefore, an object of the present invention is to provide a sheet for food packaging which is effective not only for fruits and vegetables but also for a wide variety of food products including fresh fish and salt dried products, which is effective for keeping freshness and storage.

(Structure of the Invention) The present invention is specified as a soft porous ancient marine corrosive material excavated from a foundation called Geological Journal Volume 59 No. 693 (issued in June 1953) called Tanagura Fault Fracture Zone on the southwestern margin of Abukuma. The soil quality is a substance that is effective for storage and preservation of freshness of fresh foods and salt dry matter, and it is uniformly supported on the surface of various sheet materials sold as general packaging materials, which is used to package fruits and vegetables and fresh fish. Then, while fruits and vegetables were prevented from overheating, it was completed by discovering that in fresh fish, the progress of putrefaction stopped and the freshness preservation function was extremely excellent. This is because the fine powder of the soft porous ancient marine corrosive material forming the super-porous pores is uniformly supported on the sheet-shaped support surface of synthetic resin or natural substance. "

The soft porous ancient marine corrosive used in the present invention has a chemical composition and physical properties as shown in Table 1 below, comprehensively contains various trace components, and is a conventional product shown in Table 2 61-93835), the physical properties are different from those of Otani stone, zeolite stone, and activated carbon shown in Table 3, and the average pore radius is slightly large, and the surface pH is in the neutral range of 7.4. , Those mainly composed of Otani stone etc. in the acidic range of pH 6 or less, zeolite stone and activated carbon in the alkaline range of pH 9 or more are clearly distinguished, and the oxidizing oxides and reducing oxides of inorganic metal oxides are It is characterized by being mixed well. Such a dry powder of a soft porous ancient marine corrosive material is available as Minekton and Minekton S (trade name, manufactured by Arai Bussan).

Therefore, the soft porous ancient marine corrosive material according to the present invention not only has the ability to adsorb ethylene gas like Oya stone, zeolite stone and activated carbon, but also has a long adsorption activity period as shown below, and fresh food. Good results are shown for the preservation of products. Its function will be explained based on the function diagram of the low-density polyethylene film shown in Fig. 1. When the fruits and vegetables are directly packaged in such a film to maintain the freshness by the simple CA effect, the gas permeability and the moisture permeability are improved. It has the effect of preventing fogging and dew condensation. The low-density polyethylene film containing the dry powder of the soft porous ancient marine corrosive substance is planned to be sold by the present applicant under the trade name "Minelap" and is available.

 Hereinafter, the present invention will be described in detail based on specific examples.

(Production example of soft porous ancient marine corrosive dry powder) The soft porous ancient marine corrosive should be prepared as follows.

At the mining site, it is crushed by a rock crusher, the particle size is adjusted by an air sorter to ensure quality, and then it is naturally dried. The dry powder has a size of 60 mesh and a diameter of 250μ of about 0.173 mm. Take a small amount of such dry powder on a slide glass, suspend it in a small amount of water, cover with a cover glass,
When the micrograph was taken, it was as shown in FIG.

Further, this is dried and sterilized by projection with far infrared rays at 100 ° C. for 48 hours. Furthermore, since ultrafine powder is required for the production of polysheet, ultrafine powder is again used to remove foreign substances and make uniform. Grain size is adjusted. The powder after ultra-fine pulverization is 325 mesh and the diameter of 44μ is 0.028mm. A small amount of this dry powder was placed on a slide glass, suspended in a small amount of water, covered with a cover glass, and a micrograph was taken, which was as shown in FIG.

(Example of manufacturing packaging sheet) The above-mentioned soft porous ancient marine corrosives are distributed evenly on the surface of a sheet-like carrier to form a packaging sheet, and fresh food is packaged and used to maintain freshness. It is suitable. As the sheet-shaped carrier, a synthetic resin, for example, a sheet-shaped material produced by stretching an olefin polymer material such as polyethylene or polypropylene used as a packaging film into a film or synthetic or natural paper, for example, wrapping paper is used. Is good. Alternatively, various packaging materials can be formed by mixing with foam material such as Styrofoam.

In order to uniformly disperse the substance of the present invention on the surface of a sheet carrier, the above-mentioned Minexton or Minexton S may be mixed into a synthetic resin sheet material or paper pulp to form a sheet by a conventional method, or a coating agent may be formed on the surface of the sheet material. You may manufacture it by mixing with and forming a film.

In the polyethylene sheet, when the amount of the soft and porous ancient marine corrosives with respect to polyethylene is 10% by weight, preferably 7% by weight or more, it is difficult to form the sheet.

On the other hand, if it is less than 0.5% by weight, the adsorption performance of ethylene gas is deteriorated and the freshness-maintaining effect is not sufficient.

Therefore, when using a synthetic resin as a sheet carrier,
The amount of soft porous ancient marine corrosives is 0.5-10% by weight,
It is preferably 1 to 7% by weight.

When paper is used as a sheet-like carrier, the function as a wrapping paper is not impaired by mixing soft porous ancient marine corrosives in an amount of 10% by weight or more, but 15 is required for uniform surface dispersion to maintain adsorption performance. Up to wt% is suitable.

(Example of freshness retention test of fruits and vegetables) Spinach, strawberry, tomato, tangerine "early life" is used, and the production method is unknown, but a general polyethylene sheet (hereinafter referred to as a general poly sheet), which is commercially available as a packaging sheet, is also available. Although the production method is unknown, it is commercially available as a packaging sheet. Oyaishi shown in Table 2, a polyethylene sheet containing a pore chamber material containing silicic acid anhydride as a main component such as zeolite and cristobalite (trade name Ainaka, Manufactured by Thermo Co., Ltd. in Tokyo, Japan) (hereinafter referred to as "conventional product"), and synthetic resin sheet material containing 1% by weight of Minexton S.
The low-density polyethylene sheet according to the present invention (trade name Minerap manufactured by Arai Bussan Co., Ltd.) (hereinafter referred to as the present invention product) mixed and formed into a sheet by a conventional method was sealed and packaged, and the freshness retention performance was tested. The results are shown in Table 4 below.

(1) In the case of general polysheets, most of the spinach is in a rotten state, whereas in the case of the product of the present invention, it is slightly abraded, but there is almost no change.

(2) With regard to strawberries, in the case of general polysheet, aging progressed and most of them became rotten, whereas the product of the present invention kept its original state.

(3) Blue tomato was used, but in the case of the conventional product, it ripened red on the 5th day, and after that ripening proceeded too much, and red juice came out. The tomato turned red, but the condition was retained.

(4) Using blue "early" tangerine, sealed, at room temperature
As a result of testing for 11 days, general polysheets were matured and turned yellow. Further, even in the conventional product, yellowing started to progress from the sag portion, but in the product of the present invention, the yellowing occurred only in a small portion around the sag.

(Example of freshness preservation test of fresh fish) Thawed tuna fillets were hermetically packaged with a polyethylene sheet containing 1% by weight of Minecton S (trade name: Minewrap) and a general polyethylene sheet, and stored in a cool case provided at a sushi restaurant counter. The surface color change of the tuna fillet packaged with the general polyethylene sheet was observed after 7 days, whereas the surface color change was not observed with the tuna fillet packaged with the sheet of the present invention.

(Example of Storage Test of Salt Dried Material) Semi-raw sardines were sealed and packaged in a polyethylene sheet (trade name: Minewrap) containing 1% by weight of Minecton S and a general polyethylene sheet, and left at room temperature. Molds on the surface of the tuna fillets packaged with the general polyethylene sheet had mold on the surface after 7 days, whereas molds on the surface of the hermetically sealed sheet of the present invention showed no mold.

Analysis method (Ibaraki Pollution Control Association) (1) Items (1) to (3) above 1. Specific surface area measurement (BET-SA) Device: QUANTA CHROME QUANTA SORB OS-8 Measurement conditions: DET-1 point Method, flow method, TCD detection Pretreatment: N under 250 ℃ × 15min 2. Mercury injection method Pore distribution measurement (PD) device: Carlo Elbe 2200 type (2) Water content-sediment survey method and its explanation-1984 1.2. 3 (3) Loss on ignition-Investigation method of bottom sediment and its explanation-1984 1.2.4 (4) Items (6) to (16) -High-frequency inductively coupled plasma optical emission spectrometry (Effect of the invention) As is clear from the above description, according to the present invention, it has an ethylene gas adsorption performance similar to activated carbon, zeolite stone and Otani stone, and shows the freshness retaining effect of fruits and vegetables, but Otani stone and zeolite stone. Comparing the physical properties with activated carbon, the average pore radius is slightly larger, and the surface pH is 7.4, which is in the neutral range.
Unlike Otani stone in the acidic region of H6 or less, and zeolite stone and activated carbon in the alkaline region of pH 9 or more, the surface pH is 7.
It is in the neutral range of 4 and the oxidizing and reducing oxides of inorganic metal oxides are well mixed, resulting in a long retention period of activity and also preservation of freshness of not only fruits and vegetables but also fresh fish. Since it is suitable for the effect, its utility value as a packaging sheet for perishable foods is immeasurable.

[Brief description of drawings]

FIG. 1 is a functional explanatory diagram of a packaging sheet according to the present invention, and FIG.
FIG. 3 and FIG. 3 are views showing a dry powder of a soft porous ancient marine corrosive material to be mixed in the sheet of the present invention, and FIG. 4, FIG. 5 and FIG. 6 are each a soft porous ancient used in the present invention. It is a graph which shows the result of the POROSITY DETERMINATION of marine corrosive.

Claims (3)

[Claims] 1. A soft porous ancient marine corrosive fine powder forming superporous pores having ethylene gas adsorption performance is uniformly supported on the surface of a synthetic resin or natural material sheet-shaped carrier. Food packaging sheet. 2. The food packaging sheet according to claim 1, wherein the sheet-shaped carrier is a synthetic resin film, synthetic paper or natural paper. 3. The sheet carrier is a synthetic resin, and the soft porous ancient marine corrosive material is 0.5 to 10% by weight based on the synthetic resin.
The food packaging sheet according to the above item 1, wherein the food packaging sheet is formed by mixing the above to form a packaging sheet thickness.