JP2568092Y2 - Fermented material storage - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for fermented products such as miso.

[0002]

2. Description of the Related Art Fermented products such as miso always emit carbon dioxide during the ripening process. Therefore, in the container for storing fermented products, it is necessary to release carbon dioxide accumulated in the container to the outside. Further, in fermentation of the fermented product, if oxygen is present, the surface of the fermented product is oxidized to lower its commercial value. Therefore, it is necessary that the fermented product container has a structure in which oxygen in the air does not enter the container.

[0003] For this reason, for example, a container such as raw miso that is subdivided for retail sale is usually made of an aluminum sealed container to prevent intrusion of oxygen from the outside of the container, and inside the container. A container provided with an on-off valve for releasing carbon dioxide at an arbitrary position of the container is used so that the accumulated carbon dioxide can be appropriately released to the outside. However, such a container has a complicated structure provided with the above-mentioned on-off valve, and cannot be easily manufactured, and the operation of discharging the carbon dioxide accumulated in the container by operating the on-off valve is troublesome. Further, since the open / close valve is opened / closed after the inside of the container reaches a certain internal pressure, there is a problem that the container expands until the opening / closing operation is performed.

On the other hand, Japanese Patent Application Laid-Open No. S59-216562 discloses a container made of a porous material that allows the passage of carbon dioxide as such a container for storing miso. Here, JP-A-59-216562 does not specifically describe the air permeability of a porous material used as a material of the storage container. However, the porous material specifically used in the publication is a single-layer resin sheet in which holes having a diameter of about 0.6 μm are formed. Is generally in a good state of about 50 to 2,000 seconds / 100 cc. Therefore, when the porous sheet having such good air permeability is used as a material for the storage container of the miso as described above, although carbon dioxide generated from the miso is released to the outside of the container, similarly, air is released from outside the container. Oxygen in the medium invades, and as described above, the surface of the miso is oxidized to form a dark or white film.

[0005] From the above background, carbon dioxide generated by fermentation can be released to the outside of the vessel without providing a special structure such as an on-off valve, while oxygen outside the vessel is prevented from penetrating into the inside. The development of a storage container was desired.

[0006]

Means for Solving the Problems The present inventors have intensively studied in view of the above problems. As a result, the present inventors have found that the above problem can be solved by using a porous sheet having a specific air permeability as a material of a container for fermentation products, and have come to propose the present invention.

That is, the present invention has a permeability of 30,000-
It is a fermented product container made of a porous sheet of 100,000 seconds / 100 cc.

[0008] In the present invention, the sheet used as the material of the fermented product storage container has an air permeability of 30,000 to 10
0000 sec / 100cc, preferably 40,000-
It can be used without any limitation as long as it is a porous sheet at 90,000 seconds / 100 cc. By using a porous sheet with such air permeability, the container storing the fermented product can continuously remove the carbon dioxide produced from the fermented product outside the container while maintaining an appropriate pressure inside the container to prevent the invasion of outside air. Is discharged to Here, when the air permeability of this porous sheet is smaller than 30,000 seconds / 100 cc,
Oxygen penetrates into the inside of the container from outside the container, and the surface of the miso is oxidized to form a dark or white film. On the other hand, when the air permeability of the porous sheet is larger than 100,000 sec / 100 cc, the carbon dioxide generated in the container by fermentation is not sufficiently released to the outside of the container. Problems such as rupture of the vessel occur. Such a porous sheet has a moisture permeability of 50 to 250 g / m ^2.
-It is preferable that the thickness is 100 to 500 µm at 24 hours.

In the present invention, the porous sheet having air permeability is formed by laminating a perforated sheet on a microporous sheet comprising a polyolefin and an inorganic filler dispersed in the polyolefin and molecularly oriented by stretching. Then, it is preferable to use a composite sheet adjusted to the above air permeability.
FIG. 3 illustrates a cross-sectional view of such a composite sheet. In FIG. 3, reference numeral 4 denotes a microporous sheet comprising a polyolefin and an inorganic filler dispersed in the polyolefin and molecularly oriented by stretching, and a perforated sheet 5 is laminated on one surface of the microporous sheet. Te

Here, the polyolefin is not particularly limited, and a known one can be used. Preferably, α-olefin homopolymer such as polyethylene, polypropylene, polybutene-1 or polymethylpentene;
Copolymers of olefins with other copolymerizable monomers and mixtures thereof can be mentioned. Above all, in view of the suitability of the fermented product container of the present invention, a homopolymer of ethylene, a copolymer of ethylene and another copolymerizable monomer, and a mixture thereof are preferable. In the present invention, it is a copolymer of ethylene and another α-olefin, having a density of 0.85 to 0.95 g / cm ² and a melt index of 0.5 to 10 g / 10 minutes, preferably 0.1 to 10 g / 10 minutes.
A linear low-density polyethylene of 5 to 3.5 g / 10 min is particularly preferably used because it is easy to form holes uniformly in the sheet and has excellent extrudability and stretchability. In addition, a small amount of low-density polyethylene, high-density polyethylene, or a copolymer of these polyethylenes and a polar monomer can be added. In addition, a small amount of a pigment, a stabilizer and the like can be added to the above-mentioned polyolefin.

Known inorganic fillers can be used without any limitation. For example, Periodic Table IIA
Oxides, hydroxides, carbonates or sulfates of one kind of metal selected from the group consisting of Group IIIA, Group IIIA, Group IVA and Group IVB. When these inorganic fillers are specifically exemplified, the metal of Group IIA of the periodic table is an alkaline earth metal such as calcium, magnesium and barium, and the metal of Group IIIA is
Preferred are metals such as boron and aluminum, and the group IVA metal is silicon, and the preferred group IVB metal is a metal such as titanium, zirconium and hafnium. Oxides, hydroxides, carbonates or sulfates of these metals can be used without particular limitation. Specific examples of particularly preferably used inorganic fillers include oxides such as calcium oxide, magnesium oxide, barium oxide, aluminum oxide, boron oxide, silicon oxide, titanium oxide, and zirconium oxide; calcium carbonate, magnesium carbonate , Barium carbonate and other carbonates; magnesium hydroxide,
Hydroxides such as calcium hydroxide and aluminum hydroxide;
And sulfates such as calcium sulfate, barium sulfate, and aluminum sulfate. In addition, when the container of the present invention is used particularly for storing fermented foods such as raw miso, the porous sheet used as the material of the container is a standard that regulates a synthetic resin-made packaging container. If polypropylene is used as the polyolefin, the porous sheet must pass Ministry of Health and Welfare Notification No. 20. In this case, it is preferable to use aluminum oxide, silicon oxide, titanium oxide, barium sulfate, or the like as the inorganic filler.

Although the particle size of the above-mentioned inorganic filler is not particularly limited, the average particle size of the inorganic filler is 0.1 to 0.1 in consideration of the fineness of the holes formed in the sheet and the dispersibility in the sheet.
It is preferably 5 μm, and the maximum particle diameter is preferably 20 μm or less.

The mixing ratio of the polyolefin and the inorganic filler is not particularly limited, but it is easy to adjust the air permeability of the sheet desired by the present invention by laminating a perforated sheet described later, or Considering the dispersibility of the inorganic filler in the sheet, etc.
% By weight, and 40 to 70% by weight of the inorganic filler. The mixing of the polyolefin and the inorganic filler is performed by a known method, for example, using a Henschel mixer. Next, as a method for forming a sheet, generally, an inflation molding method or an extrusion molding method using a T-die is preferably used.

The thus obtained sheet comprising the polyolefin and the inorganic filler dispersed in the polyolefin is then subjected to molecular orientation by stretching in at least one direction, and the sheet between the polyolefin and the inorganic filler is formed. To form pores to form a microporous film.
Here, the stretching is performed in at least a uniaxial direction by a tenter stretching machine, an air inflation stretching machine, a mandrel stretching machine, or the like. In the case of performing biaxial stretching, a biaxial stretching method of sequentially performing biaxial stretching in the vertical and horizontal directions or simultaneously performing biaxial stretching in the vertical and horizontal directions is employed. The stretching conditions are generally carried out at a stretching temperature of not lower than room temperature and a melting point of the polyolefin, and the stretching ratio is 1.5 to 3.0 times in the longitudinal direction and 1.2 to 2.5 times in the transverse direction. However, it is suitable for obtaining excellent strength characteristics. In addition,
In some cases, the inorganic filler contained in the sheet, after the above stretching, to make the pores formed in the sheet larger by extracting with an extractant such as water or an aqueous acid solution that does not substantially deteriorate the polyolefin. Can also. In this case, the inorganic filler to be mixed must be soluble in water or an aqueous acid solution or other extractant solution.

The microporous sheet obtained as described above usually has an air permeability of about 50 to 2,000 seconds / 100 cc. Such a microporous sheet usually has a moisture permeability of 3,000 to 6,000 g / m ² · 24 hr and a maximum pore diameter of 5 μm or less.

Next, in the perforated sheet to be laminated on such a microporous sheet, holes are formed at an opening ratio such that the air permeability of the obtained composite sheet is in the range of 30,000 to 100,000 seconds / 100 cc. There is no particular limitation as long as it is formed. The aperture ratio of such a sheet is appropriately determined according to the air permeability of the laminated microporous sheet. Generally, the air permeability of the laminated microporous sheet is 50 to 50 as described above.
When in the range of 2,000 seconds / 100 cc, this aperture ratio is usually adopted from the range of 0.2 to 10%. The diameter of the holes formed in the sheet is not particularly limited, but is preferably 50 to 2000 μm.

The material of the perforated sheet is not particularly limited, but polyolefins such as polyethylene and polypropylene, ethylene-vinyl acetate copolymer,
Polyvinyl alcohol, polyethylene terephthalate,
Examples thereof include polyamide, polyvinyl chloride, and mixtures thereof. In particular, when the porous sheet having the above specific air permeability is used as a sealing sheet for the outlet of the fermented product in the fermented product storage container, ethylene-ethylene is used because of the good peelability of the sealed sheet from the container body. It is preferable to use a vinyl acetate copolymer. As a method for laminating such a perforated sheet on the microporous sheet, a method of thermocompression bonding the two or a method of sticking them through an adhesive is used without any limitation.

As shown in FIG. 4, a porous sheet, such as the above-mentioned composite sheet, which is a material of the container of the present invention, as far as the air permeability does not deviate from the above-mentioned specific value, as shown in FIG. Paper such as paper may be laminated.

The container of the present invention can be employed without any limitation as a container for various fermented products. Here, the fermented product is not particularly limited as long as it is an object in which fermentation, that is, a phenomenon in which organic substances are decomposed by microorganisms under anaerobic conditions to generate carbon dioxide has occurred. It is preferably used as a container for fermented products in the aging process of fermented foods such as miso, soy sauce, and dairy products, and more preferably, as a container for raw miso that is subdivided for retail sale. In the present invention, the porous sheet having the specific air permeability is not necessarily used as a material of the entire container, but may be used as a material of a part of the container. In particular, it is preferably used as a cover for closing the upper opening of the container in which the fermented product is stored, for example, as the sheet 2 for closing the miso take-out opening of the raw miso container 1 for retailing as shown in FIG. In such a case, such a porous sheet is preferably used as a member occupying at least 10% or more of the outer surface of the container. FIG. 2 is a view showing another embodiment of the fermented product container of the present invention, in which the whole raw miso 3 is packaged with a porous sheet 2.

[0020]

[Effect of the Invention] According to the fermented product storage device of the present invention, the carbon dioxide produced from the fermented product is sequentially discharged to the outside while being kept at an appropriate internal pressure for preventing the invasion of outside air. . Therefore, for example, when storing the fermented miso as a fermented product, the container does not expand due to the accumulation of carbon dioxide, and the surface of the miso in the container is oxidized by the invasion of oxygen, and the surface of the container is oxidized. There is no darkening.

[0021]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

In the present invention, the air permeability and the moisture permeability of the sheet were measured by the following methods.

1) Air permeability: Measured according to JIS-P-8177 (Gurley method) 2) Moisture permeability: JIS-Z-0 at 40 ° C. and 90% relative humidity
Measured in accordance with G.208 (g / m ² · 24 hr) Example 1 Air permeability 100 sec / 100 cc, moisture permeability 4800 g / m ²
・ Microporous sheet (24 sheets, NF sheet S-14 manufactured by Tokuyama Soda Co., Ltd.)
0 "), a perforated sheet of an ethylene-vinyl acetate copolymer in which pores having a pore diameter of 400 μm are formed so as to have an opening ratio of 0.5% (“ Hirodine 757, manufactured by Hirodyne Co., Ltd.)
3T film "was laminated by thermocompression bonding. The air permeability of this porous sheet is 60,000 seconds / 100 cc.
, The moisture permeability was 90 g / m ² · 24 hr, and the thickness was 170 μm. Next, the capacity is 940cm
^{In step 3} , 750 g of the raw miso, which is in the process of ripening, is placed in a polyethylene terephthalate container having an outer surface area of 580 cm ² and an upper opening area of 135 cm ² , and the porous sheet is attached to the upper opening. The opening surface was closed.
After storage at 25 ° C. for 30 days, the raw miso container was observed, and no expansion or the like due to an increase in the internal pressure in the container was observed. When the miso inside the container was taken out, no abnormality such as darkening was observed on the surface of the miso.

Example 2 The procedure of Example 1 was repeated, except that the aperture ratio of the holes formed in the perforated sheet of ethylene-vinyl acetate copolymer was 0.3% and 1.0%. Te, air permeability of 80,000 seconds / 100cc, moisture permeability of 70g / m ² · ²
4 hr porous sheet and air permeability 50,000 sec / 1
A porous sheet having 00 cc and a moisture permeability of 120 g / m ² · 24 hr was produced.

Next, a preservation test of the raw miso was carried out using each of the porous sheets in the same manner as in Example 1. When any of the porous sheets was used, the expansion of the storage container and the stored miso were performed. No surface alteration was observed.

COMPARATIVE EXAMPLE 1 The procedure of Example 1 was repeated, except that the aperture ratio of the holes formed in the perforated sheet of ethylene-vinyl acetate copolymer was changed to 3.5%. 2,000 seconds /
A porous sheet having 100 cc and a moisture permeability of 350 g / m ² · 24 hr was produced.

Next, a preservation test of raw miso was carried out using this porous sheet in the same manner as in Example 1. After storage for 30 days, no expansion of the storage container was observed, but the storage was performed. Darkening of the surface occurred in the miso.

COMPARATIVE EXAMPLE 2 The procedure of Example 1 was repeated, except that the opening ratio of the holes formed in the perforated sheet of the ethylene-vinyl acetate copolymer was changed to 0.1%. A porous sheet of 2,000 seconds / 100 cc and a moisture permeability of 40 g / m ² · 24 hr was produced.

Next, a preservation test of raw miso was carried out using this porous sheet in the same manner as in Example 1. After storing for 30 days, the porous sheet stuck on the upper opening surface of the storage container became It was swollen due to the internal pressure of the container.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which raw miso is stored in a fermented product storage container which is a typical embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which raw miso is stored in a fermented product storage container according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view of a typical embodiment of a porous sheet constituting the fermented product container of the present invention.

FIG. 4 is a sectional view of another embodiment of the porous sheet constituting the fermented product container of the present invention.

[Explanation of symbols]

 1: container 2: porous sheet 3: raw miso 4: microporous sheet 5: perforated sheet 6: hole 7: paper

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-216562 (JP, A) JP-A-4-229253 (JP, A) JP-A-4-73136 (JP, A) JP-A-57-216 191057 (JP, A) Fully open Showa 61-80288 (JP, U) Fully open Showa 62-95589 (JP, U) Fully open Showa 63-17091 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A fermented product container comprising a porous sheet having an air permeability of 30,000 to 100,000 seconds / 100 cc.