JPH0662182B2 - Gas absorbent package - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a gas absorbent package mainly enclosed in an aseptically packaged food container, and in particular, to rupture a bag when heated with a food in a microwave oven. The present invention relates to a gas absorbent package.

[Conventional technology]

Traditionally, packaging materials with excellent oxygen gas barrier properties have been used to prevent oxidative deterioration of foods, and in order to reduce the oxygen gas content in the packaging, there has been a method of replacing the packaging gas with nitrogen or carbon dioxide. However, this method requires expensive gas replacement equipment and replacement gas. Therefore, for the contents other than liquid, such as miso, cooked rice, rice cake, buckwheat, ham, jelly and other dried products, as a method of easily removing oxygen in the package than the gas displacement packaging method, an oxygen absorbent It is known how to use. In other words, a packaging material with high oxygen gas permeability such as paper or polyethylene, which is made by packaging metallic iron or ascorbic acid with activated carbon, is used to introduce an oxygen absorber called oxygen absorber into the food packaging container and seal it. The amount of internal oxygen gas is reduced. These oxygen scavengers easily react with oxygen at room temperature to form a stable substance, which can reduce the amount of oxygen gas in the package. The rate of reduction of oxygen gas is determined by the amount of oxygen gas permeation through the food packaging material and the type and amount of oxygen absorber introduced, but generally it reaches a percentage of several percentages within 6 hours to 3 days after inclusion of the oxygen absorber. Is designed to be.

Recently, unlike the retort sterilization technology, aseptic packaging technology that can provide high quality foods without applying excessive heat to the foods has been actively performed, and aseptic packaged processed foods are now on the market. This is generally a tray-shaped container is used rather than a pouch type,
Instead of warming with hot water and eating, many things are heated in the microwave in the container and put on the table as they are. Even in this aseptic packaging, the oxygen gas in the packaging deteriorates the food,
The amount of oxygen gas in the package is being reduced by the oxygen absorbent. By the way, since the above-mentioned oxygen absorbent is heated by microwave irradiation, if the food is cooked in a food container in a microwave oven while being enclosed with the food, the bag of the oxygen absorbent is broken due to thermal expansion and the oxygen absorbent is broken. Are mixed in the food. In order to avoid this, conventionally, the food container is made permeable to oxygen gas, which is covered with an oxygen gas impermeable bag, and an oxygen absorbent is enclosed therein.

[Problems to be solved by the invention]

The oxygen absorbent package is not very effective unless it is placed in a container that directly packages food. An object of the present invention is to provide an oxygen absorbent package that does not break even when irradiated with microwaves in a microwave oven, and is packaged by enclosing it in a food container that is cooked in a microwave oven. It is possible to provide a packaged food that can be cooked in a microwave oven and that effectively reduces oxygen gas.

Another object of the present invention is to provide an oxygen absorbent package which does not require high cost packaging such as double packaging.

[Means for solving problems]

The bag for enclosing the gas absorbent is made of a laminate of a dielectric sheet (including non-woven fabric) and a metal sheet, and the metal sheet has a hole with a maximum linear distance of 30 mm (a hole with a maximum linear distance of 30 mm). The minimum line width (the minimum distance between holes and one side or the distance between holes) is 2 mm, and at least one is provided.
The gas absorbent package thus made does not break when it is affixed to the lid of a food container, packaged with food and cooked in the microwave with the food.

[Action]

The metal sheet, which is a conductor, reflects microwaves. The reflecting action has an effect that even if a hole having a maximum linear distance of 30 mm is provided in the metal sheet, it is sufficient to reduce the heating of the gas absorbent by microwaves and the gas permeability is improved. If the minimum line width is 2 mm, the metal sheet itself will not be excessively heated by the microwave. Therefore, if the gas absorbent is packed in a bag made of a laminate of such a metal sheet and a gas permeable dielectric sheet, even if oxygen gas or the like passes through and is cooked in a microwave oven, the bag should be broken by heating. It is possible to obtain a gas absorbent package that does not have

Below, a commercially available oxygen absorber package is put in an outer bag of a laminated body containing a metal aluminum foil (hereinafter referred to as a laminated body), which is enclosed in a 220 cc polypropylene tray together with water and heated in a microwave oven to absorb oxygen. The results of measuring the temperature of the agent when various holes are provided in the metal aluminum foil are shown.

The temperature of the oxygen absorbent was measured by the device shown in FIG.

The oxygen absorber used is called Ageless S under the trade name and is for iron-based, self-reactive, and high-moisture products. The microwave oven used is National Microwave NEN-200 (2.45).
GHz, output 400 W). The measured data are shown in Table 1.

As shown in Table 1, when the laminate was covered with a metal aluminum foil laminate having holes with a diameter of 30 mm or less, the oxygen absorbent did not expand by heating for 1 minute in a microwave oven.

Next, the test results for gas barrier properties are shown. When using a metal foil having an excellent gas barrier property as a packaging material, it is considered that the size of the holes in the metal foil affects the time required to remove oxygen in the packaging. It is considered that when the pore size is large and a large number are opened, the oxygen permeation amount is sufficiently large, but when the pore size is small and the number is small, the oxygen permeation amount is considerably small.

There is no total pressure difference between the inside and the outside of the through-hole regarding the size and the oxygen gas permeability of the through-hole that is opened in the aluminum foil.
The measured values when the oxygen gas partial pressure is 2 atm are shown in Table 2.

The measured values when there is a total pressure difference between inside and outside are shown in Table 3.

Only one hole with a diameter of 200μ opens 55.
Oxygen gas of 2cc passes and even a hole with a diameter of 25μ is 3.7cc
Oxygen gas passes through. When the total pressure on the outside of the hole is higher than that on the inside, a larger amount of oxygen gas passes as shown in Table 3 because a gas flow is added. From this, it is clear that the performance of the oxygen absorbent is not deteriorated by using a dielectric sheet having a large gas permeability such as a non-woven fabric and a metal foil having through holes.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

Example 1 As shown in FIG. 1, the oxygen gas absorbent 1 (product name Ageless S) was packaged as follows. Thickness 9μ Diameter D = 1,5,13,19,2 on commercial aluminum foil 2
A large number of 5 and 30 mm holes 5 were opened, and a commercially available product of 12μ biaxially oriented polyethylene terephthalate (BOPET) 3 was used on one surface using urethane adhesive and a commercially available product was used on the other surface.
0μ polyethylene (PE) film 4 is attached and BOP
A laminate of ET / perforated AI / PE was prepared. A 65 × 70 mm square flat bag was prepared using this laminate, and about 10 g of the gas absorbent 1 was filled and sealed, and the oxygen gas absorbent package 6 was formed.
It was created. As shown in FIG. 2, as a plastic container, polypropylene / EVAL (trade name) / polypropylene laminated tray 7 (size: 100 × 140)
mm, depth 25 mm, internal volume: 200 g), using a lid 8
Used a polypropylene / Eval / polypropylene laminated film. (Hereinafter, the tray and the lid are referred to as a food container.) As shown in FIG. 2, the food container was filled with about 150 g of cooked rice 9 and hermetically sealed with a lid 8 to which the oxygen gas absorbent package 6 was attached. A commercially available microwave oven (National microwave oven NEN-200 manufactured by Matsushita Electric,
2.45 GHz, output 500 W. The heating was performed using a microwave oven). As a result, cooked rice was heated to an optimum temperature for use in food without breaking the oxygen gas absorbent package of aluminum foil with holes of each size.

Comparative Example 1 Cooked rice was heated under the same conditions as in Example except that the diameter of the holes in the aluminum foil was 35 mm. As a result, the oxygen gas absorbent package was heated and inflated in about 60 seconds in the microwave oven to rupture the bag, and the oxygen gas absorbent was mixed in the cooked rice.

Example 2 The packaging of the oxygen gas absorbent was performed as follows. Thickness 9μ Commercially available metal aluminum foil is provided with a large number of holes each having a regular triangle of 16 mm on one side, a square, and a regular hexagon of 8 mm on each side, and a commercially available 40 μ polyethylene (PE) film is bonded to one side using urethane adhesive. , Irregular perforated AI / PE
A laminated body of Using this laminated body, a PE × 65 mm × 70 mm square flat bag is prepared, and about 10 g of a commercially available iron-based oxygen gas absorbent (product name Ageless S) is filled and sealed to create an oxygen gas absorbent package. did.

About 150 g of cooked rice is filled in a food container, and the oxygen gas absorbent package is hermetically sealed with a lid attached inside. A gas vent hole was opened in a part of the lid, and the lid was heated in a microwave oven. As a result, all of the oxygen gas absorbent packages were heated to the optimum temperature to be used for food without breaking the bag by microwave treatment.

Example 3 A packaged product of oxygen gas absorbent is a commercially available iron-based oxygen absorbent (size: 65 × 70 mm amount of oxygen gas absorbent: about 10 g, packaging form: three-sided flat bag, packaging material: paper / polyethylene laminated film, product Name Ageless F) is used, and as an outer bag, a commercially available aluminum foil with a thickness of 9μ is opened with holes of 13 mm in diameter (18 holes on both sides) and 30 mm (8 holes on both sides), and a urethane adhesive is used. 40 on one side
Adhesion of μ polyethylene (PE) film and opening
A laminated body of PE was prepared, and a bag with the PE inside was used. The package of the oxygen gas absorbent was attached to the inside of the lid of the food container, about 150 g of cooked rice was filled in the food container, and the lid was hermetically sealed. As a result of storing these samples at room temperature for 30 days, all the samples were in a state of being sufficiently edible without any change such as generation of mold.

Comparative Example 2 A test was carried out under the same conditions as in Example 3 except that the metal aluminum foil of the outer bag was not provided with holes. Mold was generated in cooked rice as a result of storing the sample at room temperature.

Comparative Example 3 The packaging of the oxygen gas absorbent was performed as follows. Commercially available 12μ biaxially oriented polyethylene terephthalate (BOPE
T) A urethane adhesive is used for the film,
Bonding 0μ polyethylene (PE) film, BOPE
A laminate of T / PE was created. Using this laminate, 6
A 5 × 75 mm square flat bag was prepared, and about 10 g of a commercially available iron-based oxygen gas absorbent (product name Ageless S) was filled and sealed to prepare an oxygen gas absorbent package. This oxygen gas absorbent package was attached to the inside of the lid of the food container, the food container was filled with about 150 g of cooked rice, and the lid was hermetically sealed. When a gas vent was opened in a part of the lid and heated in a microwave oven, the package of the oxygen gas absorbent expanded and broke in about 40 seconds in the microwave oven, and the oxygen gas absorbent was mixed in the cooked rice. .

Comparative Example 4 The oxygen gas absorbent is a commercially available package (size: 65 × 70 m
m, amount of oxygen gas absorbent: about 10 g, packaging form: three-sided flat bag, packaging material: paper / polyethylene laminated film, trade name Ageless S), and the same test as in Comparative Example 3 was performed. As a result, the package of the oxygen gas absorbent was heated and expanded in about 45 seconds in the microwave oven, the bag was broken, and the oxygen gas absorbent was mixed in the cooked rice.

Example 4 The packaging of the oxygen gas absorbent was performed as follows. Thickness 20
A hole with a diameter of 30 mm is opened in a commercially available iron foil of μ so that the minimum line width (hole and one side or the minimum distance between holes) is 2.0 mm and 2.5 mm, respectively, and one side is coated with urethane adhesive. A commercially available 12μ biaxial polyethylene terephthalate (BOPET) film is bonded to the other surface, and a commercially available 40μ polyethylene (PE) film is adhered to the other surface.
A laminate of OPET / perforated AI / PE was prepared. A 65 x 70 mm square flat bag is made using this laminate, and about 10 g of a commercially available iron-based oxygen gas absorbent (trade name Ageless S) is used.
After filling and sealing, a package of oxygen gas absorbent was prepared. This package of oxygen gas absorbent is adhered to the inside of the lid of the food container, the food container is filled with about 150 g of cooked rice, and the lid is hermetically sealed, and then a gas vent hole is opened in a part of the lid and heated in a microwave oven. did.

As a result, cooked rice was heated to the optimum temperature for serving without breaking the package of the oxygen gas absorbent.

Comparative Example 5 A test was conducted in the same manner as in Example except that the minimum line width (the minimum distance between holes and one side or the minimum distance between holes) was 1.5 mm. As a result, the portion with the smallest line width generated heat and the oxygen gas absorbent package was broken.

Although the examples describe the oxygen gas absorbent,
It is obvious that the same can be applied to an absorbent such as ethylene gas which deteriorates the preservability of food.

〔The invention's effect〕

As described above, the gas absorbent package according to the present invention does not rupture by heating even when subjected to microwave treatment, so that it can be directly enclosed in the package of food to be microwave-cooked, so that the gas absorption effect can be obtained. Can be increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a gas absorbent package according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a state in which the gas absorbent package according to an embodiment of the present invention is enclosed in a food container. FIG. 3 is a diagram showing an outline of an apparatus for measuring a temperature rise of an oxygen absorbent in a food container due to heating in a microwave oven. 1 ... Oxygen gas absorbent, 2 ... Metal aluminum foil.

Claims (1)

[Claims] 1. A package comprising a laminate of a metal sheet enclosing a gas absorbent and a gas permeable dielectric sheet, wherein the metal sheet has a hole having a maximum linear distance of 30 mm and a minimum line. A gas absorbent package packaged in a hermetically sealed food container, characterized in that one or more having a width of 2 mm is provided.