JPH08175571A - Packaging material for fermented soybeans - Google Patents

Abstract

PURPOSE: To obtain a packaging material suitable for the fermentation, reservation, and transportation of fermented soybeans, by providing a specified packaging material which can adjust both air- and humidity-permiabilities. CONSTITUTION: A paper layer 1 with 30-200g/m<2> is applied with a synthetic emulsion-painted layer 2 to adjust the humidity-permeability while keeping the air-permeability. The characteristics of the packing material itself for fermented soybeans are set at 50sec./100cc to 1000sec./100cc in the air- permeability stipulated in JIS-P8117 and at 500-3000g/m<2> .24h in the humidity- permeability stipulated in JIS-Z0208. In this way, the packing material is appropriate for the fermentation of the packed fermented soybeans and prevents them from drying due to evaporation of water and further increases the preservability. The plastic films 3 with holes are stuck to each other through a synthetic emulsion-painted layer 2 to increase the waterproofing property while keeping the air-permeability and humidity-permeability. When the porous plastic films 3 are made to be heat-sealing layers, the productibity of the bag body is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a natto packaging material excellent in air permeability, moisture permeability, water resistance and the like and suitable for natto packaging.

[0002]

2. Description of the Related Art Conventionally, as a natto packaging material, a material mainly made of plastic such as expanded polystyrene sheet has been used. As shown in the sectional front view of FIG. 3, a thermoformed container 11 made of expanded polystyrene sheet, and a container made of a thin plastic film such as an inner lid 13 and an outer lid 13 are suitable for fermenting, storing, and distributing natto. Widely used as a packaging container form.

[0003]

Since the conventional natto packaging materials described above are mainly composed of plastics, it is costly to dispose of wastes after use, and the foamed sheets are bulky, resulting in storage efficiency and transportation. There is a problem of inefficiency.

Further, since the supply of oxygen and evaporation of water necessary for fermentation are mainly performed from the upper surface of the container, there is a problem that fermentation failure easily occurs at the bottom of the container and that natto becomes soft at the bottom of the container.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a natto packaging material in which the material itself can be adjusted in both air permeability and moisture permeability and can be used as a bag body as it is. A natto packaging material obtained by adhering a perforated plastic film to at least one surface of a paper layer having a paper thickness of 30 g / m2 to 200 g / m2 through a synthetic resin emulsion coating layer, according to JIS-P8117. Air permeability is 5
0 sec / 100 cc to 1000 sec / 100 cc, JIS-
Water vapor permeability of Z0208 is 500g / m2 ・ 24hr ～ 30
The present invention relates to a natto packaging material having a characteristic of 00 g / m 2 · 24 hr, which will be described below with reference to the accompanying drawings.

FIG. 1 is an enlarged partial sectional view showing an example of the natto packaging material of the present invention, and FIG. 2 is a sectional front view showing an example of a natto packaging body with a bag using the natto packaging material of the present invention. FIG. 3 is a sectional front view showing an example of a conventional natto package.

In the present invention, as shown in FIGS. 1 and 2, the paper thickness is 3
A natto packaging material obtained by adhering a perforated plastic film 3 to at least one surface of a paper layer 1 of 0 g / m2 to 200 g / m2 via a synthetic resin emulsion coating layer 2, and having a gas permeability of JIS-P8117. 50 seconds / 100 cc
~ 1000 seconds / 100cc, JIS-Z0208 moisture permeability is 500g / m2-24hr-3000g / m2-2
It is a natto packaging material having a characteristic of 4 hours.

The function of the present invention is that the paper thickness is 30 g / m 2 -2.
Synthetic resin emulsion layer 2 on 00g / m2 paper layer 1
By adjusting the moisture permeability while ensuring the air permeability, the characteristics of this natto packaging material itself are specified in JIS-P811.
Air permeability of 7 is 50 seconds / 100 cc to 1000 seconds / 100
cc, JIS-Z0208 moisture permeability is 500g / m2 ・
24 hours to 3000 g / m 2 · 24 hours is suitable for the fermenting action of natto to be packaged, and exhibits the action of improving the shelf life by preventing the drying of natto by evaporation of water.

By adhering the perforated plastic film 3 through the synthetic resin emulsion coating layer 2, water resistance is improved while maintaining air permeability and moisture permeability,
Further, the perforated plastic film 3 is used as a heat seal layer to facilitate the production of the bag.

The paper in the present invention includes strength, rigidity,
From the perspective of air permeability, moisture permeability, heat retention, or not bulky, ordinary kraft paper as specified by JIS standard,
Those having a thickness of about 30 g / m @ 2 to 200 g / m @ 2 can be used. Further, waterproof paper, Japanese paper, interleaving paper, etc. can also be used.

The function of this paper is to secure an appropriate air permeability, absorb excess water to prevent alteration of the contents, and to maintain a certain degree of heat retention due to the voids between the fibers. It plays the role of preventing condensation on the inner surface due to temperature changes.

When the thickness is 30 g / m 2 or less, the heat retaining property is not sufficient, and when the synthetic resin emulsion coating layer 2 is formed, it penetrates the paper layer and wraps around to the back surface. There is a problem that it is difficult to adjust the temperament and moisture permeability.

On the other hand, when the thickness is 200 g / m 2 or more, there is a problem that the heat-sealing takes time due to the heat insulating effect and the rigidity is increased, so that the bag manufacturing efficiency is lowered.

In the present invention, the synthetic resin emulsion coating layer 2 is obtained by applying synthetic resin emulsion onto the surface of the paper layer 1.
It is impregnated and cured, and its function is to strengthen the surface of the paper layer 1 while ensuring the air permeability without forming a completely continuous film by soaking into the surface of the paper layer 1 to some extent. In addition, the water resistance is significantly improved compared to paper alone.

The synthetic resin emulsion used in the present invention means an ethylene-vinyl acetate copolymer resin, an ethylene acrylic acid copolymer resin, a mixture of an acrylic resin and a styrene resin, or a polyvinylidene chloride resin suspended in water. Emulsion is used.

Paraffin may be added to these synthetic resin emulsions to improve the characteristics such as slipperiness and moisture permeability, or titanium may be added to improve the air permeability.

Further, since the synthetic resin emulsion is impregnated and hardened in the paper layer 1 and the state thereof is unlikely to change due to heating, there is no fear of impairing the air permeability when the perforated plastics 3 is thermocompression-bonded, and the thermocompression bonding is performed. Since it does not require an adhesive because it is possible, it is not contaminated by residual solvent, and it has water resistance that it is difficult for water to permeate.

As the perforated plastic film 3 used in the present invention, one or more small holes 31 having a diameter of 0.05 mm to 1.0 mm are formed per cm 2 in the plastic film 3 made of polyethylene, polypropylene, polyvinyl chloride, polyamide or the like. What was done is used suitably. Small hole 3
If the diameter of 1 is 0.05 mm or more, the small holes 31 are less likely to be blocked during bonding, and if it is 1.0 mm or less, the stickiness of natto may get in or the natto may be caught, making it difficult to remove.

If the total area of the small holes 31 is divided by the total area including the small holes 31 of the plastic film 3 and the opening ratio (%) multiplied by 100 is 0.01% or more, fermenting of natto is performed. A suitable air permeability is obtained, and when it is 10% or less, the strength retention effect when wet with water is remarkably excellent, and it contributes to the function of suppressing water evaporation and preventing the drying of natto.

The thickness of the plastic film 3 is preferably 10 μm or more from the viewpoint of sealing property and 100 μm or less because the small holes 31 are easily formed.

The characteristics of the natto packaging material of the present invention are described in J
Air permeability of IS-P8117 is 50 seconds / 100cc-10
00 seconds / 100 cc, JIS-Z0208 moisture permeability is 5
00g / m2 ・ 24hr ~ 3000g / m2 ・ 24hr
Is required to be kept. Air permeability is 1000 seconds /
If it is less than 100 cc, there is a drawback that the air suitable for fermentation of the packed natto is not replenished and the ammonia odor of natto is not sufficiently discharged and remains.

When the air permeability exceeds 50 seconds / 100 cc,
Water may be evaporated too much and natto may be excessively dried.

If the water vapor permeability is less than 500 g / m 2 · 24 hr, water vapor will condense and the natto will become watery.

If the water vapor permeability exceeds 3000 g / m 2 · 24 hr, the water content of natto may evaporate to the outside and dry, or the water content of natto may migrate to the paper layer 1 and weaken the strength.

In order to produce the natto packaging material of the present invention, the surface of the paper layer 1 is coated with synthetic resin emulsion by a general coating device used for surface treatment of paper,
Impregnated and cured by hot air drying to form Layer 2.

Then, the perforated plastic film 3 is superposed on this layer 2 and bonded by heating and pressure bonding to obtain the natto packaging material of the present invention.

In order to produce a natto package using the natto packaging material of the present invention, for example, an automatic bag making and filling device is used to stack the plastic films 3 and heat seal the three sides to form a bag. Steamed soybeans produced and inoculated with Bacillus natto may be filled, and the opening may be heat-sealed to close it, and if necessary, heated to a temperature suitable for fermentation. Of course, it is also suitable as a material for packaging fermented natto.

The natto packaging material of the present invention may be used on one side of the bag body and the other side may be made transparent by using a transparent plastic film. A bag body has an advantage that it does not occupy a lot of space, but can be used as a cup-shaped container or as a lid material.

[0029]

EXAMPLE 100 g / m @ 2 of double-coated kraft paper was used as the paper layer 1, ethylene-vinyl acetate copolymer emulsion having a water content of 25% by weight was used as the synthetic resin emulsion, and perforated plastic film 3 having a thickness of 30 .mu.m. Polyethylene film with small holes 31 with a diameter of 0.2 mm2
25 pieces per cm 2 and an aperture ratio of 1.57% were used.

The above-mentioned paper layer 1 was coated with ethylene-vinyl acetate copolymer emulsion so that the weight after drying was 10 g / m 2, impregnated, and cured by hot air drying to form a synthetic resin emulsion coating layer 2. After the formation, the perforated plastic film 3 was heated and pressed to obtain a natto packaging material.

When the synthetic resin emulsion coating layer 2 was formed and the air permeability and moisture permeability were measured from the synthetic resin emulsion coating layer 2 side, the air permeability specified in JIS-P8117 was 38 seconds / JIS-K7129 at 100 cc
The water vapor transmission rate specified by the -B method was too large to be measured.

Next, the perforated plastic film 3
Regarding the natto packaging material obtained by heat-pressing, the air permeability and moisture permeability from the perforated plastic film 3 side were measured, and the air permeability specified in JIS-P8117 was 38.
The water vapor transmission rate was 2 seconds / 100 cc, and the water vapor transmission rate defined by JIS-K7129-B method was 1760 g / m 2 · 24 hr.

Using this natto packaging material, the perforated plastic films 3 are butted against each other as an inner surface to form a three-sided seal bag having a seal width of 7 mm and an inner size of 100 mm × 100 mm, and having air permeability as shown in FIG. Container (A)
And

On the other hand, in a conventional polystyrene paper molding tray, the inner size is 95 mm in length, 95 mm in width, and 3 in height.
A tray container (B) as shown in FIG. 3 in which an inner lid 13 made of polyethylene film and an outer lid 12 made of paper were combined with 0 mm was prepared.

As a natto material, 3 very small soybeans from the United States
After washing Kg and immersing it in water with a water temperature of 15 ° C for 16 hours, wash it lightly and steam it for 45 minutes at a pressure of 1.5 Kg / cm2,
A steamed soybean inoculated by spraying natto bacteria diluted with sterile water was prepared.

The steamed soybeans were filled in the air-permeable container (A) and the tray container (B) in an amount of 50 g each, and the openings were closed, and then the temperature was 37 ° C. and the humidity was 90% RH in a constant temperature chamber. After keeping under conditions for 16 hours, temperature 5
Table 1 shows the results of the taste test conducted after holding for 32 hours under conditions of ° C and humidity of 60% RH.

The taste test method is as follows. As a panelist to perform the test, 36 people from Kanto Koshinetsu and Kumamoto Prefecture, 3 people from other areas, and a total of 39 people.

In the taste test, 50 g of natto in the air-permeable container (A) and the tray container (B) were blinded.
Was mixed with 4 cc of soy sauce and 0.5 g of Japanese mustard so that the panelists could stir it over rice.

As an evaluation method, the following 4 items are evaluated by 5 points, and "deliciousness" 5: delicious, 4: somewhat delicious, 3:
Normal, 2: Not so good, 1: Not good "stickiness" 5: Good, 4: Good, 3: Normal,
2: Slightly good, 1: Good "hardness" 5: Hard, 4: Slightly hard, 3: Normal,
2: Soft, 1: Soft "fragrance" 5: Good, 4: Good, 3: Normal, 2:
Slightly bad, 1: We evaluated it as bad, and also gave one point to each panelist's favorite person as a liking point and evaluated the sum.

[0040]

[Table 1] As shown in Table 1, natto, which was packaged and fermented in the breathable container (A) made of the natto packaging material of the present invention, had a strong stickiness of 3.18 and a proper hardness of 3.02. On the other hand, the conventional natto in the tray container (B) has a relatively low stickiness of 2.85 and a relatively soft hardness of 2.80, and 21 tastes from the breathable container (A). The result was that it was preferred by more than 18 people in the tray container (B).

This is because the breathable container (A) allows air to pass through as a whole, so that the fermentation of the whole natto proceeds evenly and the stickiness spreads throughout. It seems to have an appropriate hardness due to divergence.

[0042]

The present invention has a paper thickness of 30 g / m @ 2 to 200 g.
A natto packaging material obtained by adhering a perforated plastic film to at least one side of a paper layer of / m2 through a synthetic resin emulsion coating layer, and having an air permeability of JIS-P8117 of 50 seconds / 100 cc to 1000 cc. Sec / 100cc,
Water vapor permeability of JIS-Z0208 is 500g / m2 ・ 24h
Since it is a natto packaging material having the characteristics of r to 3000 g / m 2 · 24 hr, it is suitable as a material for manufacturing a bag body because it is easy to dispose of waste because it is mainly composed of a paper layer and does not become bulky. It has characteristics of both air permeability and moisture permeability that are ideal for packaging natto, and by adjusting the paper layer, the material of synthetic resin emulsion, the number of applications or the opening rate of perforated plastic film, etc. Both the air permeability and the moisture permeability can be easily realized, and the bag body made of the present packaging material having excellent water resistance has an effect that seasoning liquid can be seasoned in the bag body without exuding the seasoning liquid.

[Brief description of drawings]

FIG. 1 is an enlarged partial sectional view showing an example of a natto packaging material of the present invention.

FIG. 2 is a sectional front view showing an example of a natto package with a bag using the natto packaging material of the present invention.

FIG. 3 is a sectional front view showing an example of a conventional natto package.

[Explanation of symbols]

 1 Paper layer 2 Synthetic resin emulsion coating layer 3 Perforated plastic film

Claims (1)

[Claims] 1. A natto packaging material comprising a perforated plastic film adhered to at least one surface of a paper layer having a paper thickness of 30 g / m @ 2 to 200 g / m @ 2 through a synthetic resin emulsion coating layer according to JIS -The air permeability of P8117 is 5
0 sec / 100 cc to 1000 sec / 100 cc, JIS-
Water vapor permeability of Z0208 is 500g / m2 ・ 24hr ～ 30
Natto packaging material with the characteristics of 00g / m 2 · 24 hr.