JPH07232769A - Wrapping material and wrapper for use in microwave heating - Google Patents

Abstract

PURPOSE:To heat food with the result that a proper amount of water vapor remains on the food side and prevent the loss of food taste and appearance, by a method in which a wrapping material used for wrapping water-containing food which is heated in a microwave is made of water-vapor permeable cellophane paper formed in a tube or bag, and part of the tube or bag is provided with an oil-absorbing sheet. CONSTITUTION:A wrapping material is made by sticking together two layers of water- vapor permeable cellophane paper at one side and at rear end to form a bag 1 or by sticking them together only at one side to form a tube 2. Food 3 is put into the bag 1, its opening is loosely squeezed, and its part is tightly bound with a clip 4. Increased internal pressure is caused to escape by forming the bag after making a tiny hole in the cellophane paper in advance or by providing a weakly-stuck part when forming the bag. Therefore, by the use of the water-vapor permeable cellophane paper together with an oil-absorbing sheet, oil which builds up together with moisture when food containing much fat is heated is absorbed by the oil-absorbing sheet and separated from the food, and excellently it makes the food tasty and pleasant to the tongue, compared to the case of heating the food in wrap or heating it directly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a range heating packaging material for coating a hydrous food when it is heated by a microwave oven, a gas oven, an electric oven, etc., and a package covered with the oven heating packaging material.

[0002]

2. Description of the Related Art When a water-containing food is heated in a microwave oven, if it is heated without wrapping it, water is excessively dissipated and the food becomes dry and hard, which often impairs the taste. Also, evaporation of oil occurs along with steam,
The inside of the stove becomes contaminated and causes an offensive odor.

Therefore, conventionally, when a water-containing food is heated in a microwave oven or the like, it is generally performed by covering the food with vinylidene chloride wrap or polyethylene wrap and then heating.

[0004]

However, although these wraps are airtightly adhered to the container, since the wraps themselves do not have air permeability and moisture permeability, the wraps expand and greatly bulge into balloons when heated. Is filled with high temperature steam and becomes like steaming food, and excessive steam drops on the food on the contrary, making the surface watery or transferring to food and sucking water into grilled fish, fried food etc. There are many problems in appearance and taste. Further, if left as it is after heating, water vapor condenses and becomes a depressurized state, and the wrap presses the food, and the food is crushed and the appearance is significantly impaired.

In order to improve this drawback, a polyolefin film having pores, a laminated film of polyolefin film / paper, and the like have been proposed. Although a perforated film can release excess water vapor,
It is difficult to control the water content and it is impossible to prevent the dew condensation phenomenon. In addition, a laminated film of polyolefin / paper is inconvenient to use because the hygroscopic force of the paper is not so large that it is likely to be in an over-humidified state, and because it is opaque, the inside cannot be seen.

Further, since the wraps currently used are not biodegradable, it is necessary to incinerate them when they become waste, but since they generate a large amount of heat and produce toxic gas,
It is a cause of pollution problems.

Further, apart from the above problems, in foods such as grilled fish and fried foods with a high amount of fat, the oil flows out together with the water when heated, and the separated oil adheres to the package,
It has a drawback that it adheres to the surface of food in a bleeding state and spoils the taste.

The present invention has been made in view of the above problems, and an object thereof is to heat a water-containing food in a microwave oven by leaving an appropriate amount of steam on the food side and heating it. It is an object of the present invention to provide a packaging material for microwave oven heating that is not likely to be caused, and a package using the packaging material.

Another object of the present invention is to heat a water-containing food having a large amount of fat in a microwave oven while leaving an appropriate amount of water vapor on the food side, and at the same time, to separate the oil content leaked from the food by heating. An object of the present invention is to provide a food packaging material for microwave ovens.

[0010]

[Means for Solving the Problems] When heating water-containing foods in a microwave oven, various materials were examined based on the recognition that good foods can be obtained by leaving a proper amount of water. As a result, water-permeable cellophane paper was used. It was found that a good heated food having a proper water content can be obtained when a strong food is packaged and heated in a microwave oven, and the present invention was completed based on this.

That is, according to the present invention, the packaging material for wrapping the water-containing food when heating it in a microwave oven is formed of tubular or bag-shaped moisture-permeable cellophane paper.

Further, in the present invention, the packaging material for wrapping the water-containing food when heating the food in a microwave oven is formed of a tubular or bag-shaped moisture permeable cellophane paper, and at least the tubular or bag-shaped. The oil-absorbent sheet was placed in part.

When the food is heated to a high temperature, in order to quickly release a large amount of water vapor generated to the outside, the moisture-permeable cellophane paper is provided with pores having a diameter of 30 to 300 μm and an opening ratio of 0.
It is preferable to form the distribution at 5% or less.

The oil-absorbent sheet may be a bottom plate of a packaging material, and at least the upper surface opening or the whole of the bottom plate may be covered with the moisture permeable cellophane paper to form a bag-like structure.

Further, the oil-absorbent sheet is weighed from 30 to 30.
90 g / m ² , and its bulk density is 0.03 to 0.
It is desirable to be composed mainly of ³ g / m ³ of cellulose fibers.

Further, the cellulose fibers are made of Kapok fibers, and the Kapok fibers are contained in an amount of 20-80.
It is desirable to contain it by weight%.

In the package of the present invention, moisture-permeable cellophane is closely adhered to a container containing a water-containing food heated in a microwave oven, and the cellophane paper has a diameter of 30 to 300 μm.
, And the container is further covered with an airtight film.

The range mentioned in the present invention includes a microwave oven, a gas oven, a gas oven, an electric oven and the like.

[0019]

[Function] Moisture-permeable cellophane paper has high moisture-permeability and is most suitable as a cover when heating water-containing food in a microwave oven. Permeates part of the water vapor generated during heating, maintains an appropriate amount of water vapor inside, and absorbs condensed water even when cooled, so there is no phenomenon of dew condensation water returning to the food surface, leaving an appropriate amount of water. Heated food becomes possible.

Since cellophane paper is made of cellulose, it has the same heat resistance as paper, is transparent, and is biodegradable.
Even if it burns as waste after use, it has a low calorific value and does not generate toxic gas, so it is an extremely environmentally friendly material.

When the oil-absorbent sheet is arranged on a part or all of the inner surface of the tubular or bag-like shape, the oil content generated along with the water content when the food containing a large amount of fat is heated is absorbed by the oil-absorbent sheet. Are adsorbed on and separated from food.

When the oil-absorbent sheet is used as the bottom plate, the entire food placing portion can be utilized as the oil-absorbing portion.

When the oil-absorbent sheet is made of cellulosic fiber, it is inexpensive and has excellent moldability, and the calorific value when it is incinerated is low together with the cellophane paper, and no harmful gas is generated.

When the cellulose fiber is composed of Kapok fiber, the oil absorption performance can be further improved due to its high oil absorption property.

[0025]

EXAMPLE In the packaging material of the present invention, a moisture permeable cellophane paper is used as shown in FIG.
To form the bag body 1 by laminating one side portion and the rear edge portion as shown in FIG. 2, or to form the cylindrical body 2 by laminating only one side portion as shown in FIG. There is. The reason why the bag or the cylinder is formed in this way is that the moisture-permeable cellophane paper does not have self-adhesiveness.

The moisture-permeable cellophane paper suitable for the present invention is PT
-300, PT-350, PT-400, PT-500
Etc. moisture permeability 4000 g / m ² . 24Hr (at 20 ℃, RH
65%) and the like can be widely used. As a usage method, for example, as shown in FIG. 3, it is easy to put the food 3 in the bag-shaped 1 and squeeze the opening loosely and bind the portion tightly with a scissors 4 such as clothespins. . In this case, when the internal pressure becomes high due to steam generated by rapid heating, the pressure is released to the outside through a slight gap in the binding portion.

On the other hand, if the airtightness of the binding portion is high, the cellophane paper does not stretch, so that steam is generated and the bag is broken due to the pressurized state. Therefore, looking at the safety during use, make a bag after making fine holes in the cellophane paper beforehand, or make a weak part (or an unbonded part) in the bonding part when making a bag, It is preferable to release the increased internal pressure. The technique of perforating cellophane paper can be easily achieved by passing the cellophane paper through a roll and a rubber roll on which thin needles are planted. If the pore size is less than 30 μm, the internal pressure cannot be effectively released to the outside, and if the pore size exceeds 300 μm, the water vapor cannot be held uniformly and the water vapor can be distributed in the system, which is not desirable.

Further, as a measure for preventing the bag from breaking, it is possible to intentionally form a portion having a weak adhesive strength in a part of the bonding portion at the time of manufacturing the bag body or the cylindrical body. By making the application of the adhesive non-uniform, it is possible to easily create a weak adhesive strength portion or a non-adhesive portion. In this case, the weak adhesive strength portion or the non-adhesive portion has a ratio of 5 to that of the laminating portion. % Or less is suitable. There is no practical problem if the adhesive strength of the bonded portion is about 1/4 or less of the tensile strength of cellophane paper (PT-300 4 kg / 15 mm).

Starch-based adhesives, polyurethane-based adhesives, and vinyl acetate-based adhesives are suitable as the adhesive to which the cellophane paper is attached. As a method for applying the adhesives, a general method such as a gravure roll method can be used.

As the bag shape, a flat bag (envelope type) or a gusset bag can be used. A flat bag is suitable for containing thin ones, and a gusset bag is suitable for thick ones.

Further, in the package of the present invention, as shown in FIG. 4, the water-containing food is contained in a container 5 made of synthetic resin having excellent heat resistance. A moisture permeable cellophane 6 is coated so as to cover the food without contacting it, and the lower portion of the cellophane is airtightly adhered to the upper edge of the container. The cellophane is provided with pores having a diameter of 10 to 50 μm. The container is then hermetically covered with the airtight film 7.

This package is sold in a state of being hermetically sealed with an airtight film 7, and prevents moisture and the like from entering the inside through the moisture permeable cellophane during transportation or storage of the package. There is. When a person who purchases this packaging bag heats it, all he / she needs to do is remove the airtight film and place the container in the microwave oven. This makes it possible to heat the water-containing food inside while keeping an appropriate amount of water, which is extremely convenient in use.

The present invention will be described below with reference to specific experimental examples.

Experimental Example 1 A cooked rice, B fried chicken, C eel grilled, D horse mackerel grilled,
90 g to 100 g of each is packed in a cellophane paper gazette bag (PT-300 80 mm x 250 mm x 40 mm), vinylidene chloride wrap (saran wrap), and no packaging in a microwave oven (National NE-4000).
It was heated for a minute and evaluated. The results are shown in Table 1.

[0035]

[Table 1] Experimental Example 2 A water-permeable cellophane paper (PT-500) was perforated with 250 μm pores at an opening ratio of 0.3% to form a flat bag of 150 mm × 250 mm, and 450 g of potatoes cut in half were put therein.
4 in a gas range (NAS GR-60) heated to 0 ° C
Heated for 5 minutes. The same heating was compared to what was done without packaging. The results are shown in Table 2.

[0036]

[Table 2] The above results indicate that cellophane paper bags are effective for heating food by a gas stove.

Experimental Example 3 A water-permeable cellophane paper (PT-400) having 100 μm diameter pores perforated with an opening ratio of 0.1%, and 100 mm ×
A bag of 150 mm was prepared, 1 potato croquette was put therein, the mouth of the bag was closed with cellophane tape, and it was heated for 5 minutes with an electric oven toaster (National NT-Y1). Naked croquettes were heated under the same conditions and compared.

The cellophane paper in the bag was uniformly heated without burning. In the case of the naked one, scorching was observed on the surface on the heater side, and oil was found to adhere in the oven toaster, and the smell of oil was full.

Next, a microwave oven packaging material according to a second embodiment of the present invention will be described with reference to FIGS.

In the packaging material of this embodiment, an oil absorbing sheet is used in combination with the moisture permeable cellophane paper 1. That is, in the example shown in FIG. 5A, the upper surface center of the moisture-permeable cellophane paper 1 is overlapped and adhered to form a tubular shape, and the oil-absorbent sheet 8 is attached along the inner bottom surface in the longitudinal direction. There is. In the example shown in FIG. 5 (b), the one end opening of the cylindrical body is folded back at a predetermined folding margin 9 and adhered via an adhesive to form a flat back type bag body.

Depending on the size of the food to be stored, as shown in FIG. 6 (a), the oil-absorbing sheet 8 is attached to the inner bottom surface to form a tube-shaped moisture permeable cellophane paper at the center of both sides. It may be a gusset tube provided with an inward fold line 10 in it, or alternatively, as shown in FIG. 6B, one end 11 of the tube body of FIG.

FIG. 7 shows another example. In this example, both ends of the moisture-permeable cellophane paper 1 are bonded to the lower surfaces of both sides of the oil absorbent sheet 8 to form a tubular food packaging material.

In the example of FIG. 8, the oil absorbing sheet 8 is formed wider than that of the above example, and both end edges of the moisture permeable cellophane paper 1 are adhered to the upper surfaces of both sides of the oil absorbing sheet to form a cylindrical food packaging material. Is forming.

In the example of FIG. 9, a food storage tray 8a having flanges on both sides is formed from an oil absorbing sheet, and both end edges of the moisture permeable cellophane paper 1 are adhered to the lower surface of the flange to form a cylindrical food packaging material. Is formed.

The moisture-permeable cellophane paper used in this embodiment is the same as that in the first embodiment. As the oil-absorbent sheet 8, a bulky, many-capillary material such as Japanese paper, pulp nonwoven fabric, or cotton fabric is suitable. In particular, it is a tissue paper, a paper towel, a pulp nonwoven fabric, etc. of paper making method (wet or dry type) in which only natural cellulose is entangled with a small amount of binder, and weighs 30 to 90 g / cm ² , and has a bulk density of 0.3.
The amount of up to 0.03 g / cm ³ is preferable in terms of the oil absorption amount, its holding power, and appropriate air permeability.

Further, from the viewpoint of oil absorption capacity, the Kapok fiber currently under development is most suitable. Since this Kapok fiber is rough and stiff, it is difficult to make paper by itself,
A non-woven fabric can be formed by adding synthetic fibers. In this case, if the Kapok fiber content is less than 20% by weight, the characteristic of oil absorption cannot be exhibited, and if it exceeds 80% by weight, the production thereof is difficult.

Adhesion between the moisture-permeable cellophane 1 and the oil-absorbent sheet 8 is performed by using a starch-based adhesive, a synthetic rubber-based adhesive, a vinyl acetate emulsion-based adhesive, a chlorinated polypropylene-based adhesive or the like in a clavier roll coating, hot melt, part coat or the like. Available in the method.

In any of the above examples, in use, the hydrated food for heating the range is placed on the oil-absorbing sheet 8 in the cylinder or bag, and the openings of these cylinders or bags are lightly closed to remove the range. Put inside and heat. In this case, the surface on which the food is placed becomes the oil-absorbing surface as it is, and the oil that has exuded from the food when the food is heated is absorbed by the oil-absorbing sheet 8 at the bottom and separated from the food.

How to close the opening of this cylinder or bag is either taped, lightly tied with a rubber band or a string, or a commercially available plastic jig (CLIP-it, Daicel Craft Patic, Kureha). It may be closed by using Chemical Industry Co., Ltd. or the like.

Next, the present invention will be described with reference to specific experimental examples.

Preliminary Test 1 Prior to the production of the packaging material, the relationship between the composition of the cellulose fibers constituting the oil-absorbent sheet and the physical properties was measured, and the results shown in Table 3 below were obtained.

[0052]

[Table 3] However, *: Measured according to JIS L3204 * 2: Measured according to JIS L1086 * 3: Measured according to Japanese Pharmacopoeia * 4: Oil absorption = Oil absorption ratio x Weighing ratio Oil absorption = Weight increase / Sample weight From the above test results, it was confirmed that all of them were satisfactory in terms of oil absorption except for sample C, which had a significantly low oil absorption.

Preliminary Test 2 When the relationship between the content of Kapok fiber and the oil absorption in the mixed nonwoven fabric of the mixture of Kapok fiber and polyester fiber was examined, the results shown in FIG. 10 were obtained. A 10 cm square nonwoven fabric of 30 to 40 g / m ² was used as a sample, and a mixed edible oil of rapeseed oil / soybean oil / corn oil was used as an oil to be impregnated.

The measuring method is as follows. Immerse the above materials in mixed edible oil for 5 minutes at room temperature (25 ° C) After removing the oil, pinch it with a paper towel / newspaper to absorb excess oil and remove it as weight increase / sample own weight. Calculate the oil absorption ratio.

Experimental Example 4 Cellophane bag, cellophane bag / kapok fiber non-woven fabric of the present invention, and mackerel salt-baked in three packaging forms of deep plate wrap,
When the potato croquettes were heated in a microwave oven and taken out for comparison, the results shown in Table 4 below were obtained.

[0056]

[Table 4] However, * 1: 100 x 200 x 50 mm, mouth ... plastic clip stop * 2: 100 x 200 x 50 mm cellophane, bottom sample 3 of Table 3 is attached * 3: 150 mm diameter deep plate, Saran wrap.

The above results indicate that the packaging material of the present invention is effective, and in addition to the effect of the moisture permeable cellophane, the surplus oil content is effectively removed by the oil absorbing sheet.

Experimental Example 5 Polyethylene laminated on one side of a softwood pulp nonwoven fabric (Sample B in Table 3) was cut into 10 × 30 cm, and cellophane (PT300) 20 × 30 cm was adhered to the pulp side with starch paste. The envelope with gazette was molded, water was added to the nonwoven fabric of the envelope by spraying, then Chinese meat man was put in the envelope, and both ends were taped and heated in a microwave oven.

As a result, the surface of the meat meat taken out was not fitted, and it was confirmed that the whole was moist and uniform and had a good taste and texture as compared with the conventional wrap heating.

[0060]

As described above, when the water-containing food is heated in a microwave oven as in the present invention, the packaging material for wrapping the food is formed by a tubular or bag-shaped moisture-permeable cellophane paper. Can heat while leaving an appropriate amount of steam on the food side, so that the taste and appearance of the food are not impaired.

When the oil-absorbent sheet is used together with the moisture-permeable cellophane paper, in addition to the effect obtained by using the moisture-permeable cellophane paper, when a food containing a large amount of fat is heated, the oil content generated together with the moisture absorbs oil. Since it is adsorbed on the sheet and separated from the food, it has an advantage that the taste and texture are better than those of conventional wrap heating or direct heating, and the appearance can be impaired and contamination in the range can be prevented.

Since cellophane is made of cellulose as a raw material, it has the same heat resistance as paper, is transparent and biodegradable, and has a low calorific value when burned as waste after use.
Since it does not generate toxic gas, it is a very environmentally friendly material.

The moisture-permeable cellophane paper has a diameter of 30 to 3
When the pores of 00 μm are formed in a distributed manner with an opening ratio of 0.5% or less, a bonding portion is provided on the tubular or bag-shaped moisture permeable cellophane paper, and the bonding portion has a length of 5%. When the adhesive strength of the following parts is set to 1 kg / 15 mm or less, even if the bag-shaped or tubular opening is airtightly closed, a suitable amount of water vapor inside the bag or the tubular body when heated by the range On the other hand, the bag does not break due to a rapid increase in internal pressure during heating.

When the oil-absorbent sheet is used as the bottom plate, the entire food placing portion can be utilized as the oil-absorbing portion, which is suitable for food heating packaging.

Furthermore, when the oil-absorbent sheet is made of cellulose fiber, it is inexpensive and rich in moldability, and the calorific value when it is incinerated is low together with the above cellophane paper, and no harmful gas is generated. Is also beneficial.

When the cellulosic fiber is composed of Kapok fiber, its high oil absorbing property can further improve the oil absorbing performance, which is effective in the case of actively removing oil.

Furthermore, in the microwave oven heating heating package of the present invention, a container containing water-containing food to be heated in a microwave oven is closely adhered to and covered with cellophane, and the cellophane paper is perforated with pores having a diameter of 30 to 300 μm. Since it is installed and the container is covered with an airtight film, there is no risk of moisture entering the inside through the moisture permeable cellophane during transport or storage of the package, and it is airtight when used. By removing the film and installing the container in a microwave oven, the water-containing food inside can be heated while maintaining an appropriate water content, which is extremely convenient for use.

[Brief description of drawings]

FIG. 1 is a perspective view showing a bag-shaped packaging material according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a tubular packaging material according to a modification of the first embodiment of the present invention.

FIG. 3 is a perspective view showing a state in which a hydrous food is packaged in the bag-shaped packaging material of FIG.

FIG. 4 is a cross-sectional view showing an example of the package of the present invention.

FIG. 5 is a perspective view showing a cylinder body and a bag body according to a second embodiment of the present invention with a part thereof broken away.

FIG. 6 is a partially cutaway perspective view showing a cylindrical body and a bag body of a modified example of the second embodiment.

FIG. 7 is a perspective view showing a cylindrical body according to another modification of the second embodiment with a part thereof broken away.

FIG. 8 is a partially cutaway perspective view showing a cylindrical body according to another modification of the second embodiment.

FIG. 9 is a partially cutaway perspective view showing a cylindrical body according to another modification of the second embodiment.

FIG. 10 is a graph showing the relationship between the content of Kapok fiber and the oil absorption.

[Explanation of symbols]

 1 bag 2 cylinder 3 food 4 picking tool 5 container 6 moisture permeable cellophane 7 airtight film 8 oil absorption sheet

Claims (8)

[Claims] 1. A packaging material for heating a microwave oven, characterized in that a packaging material for wrapping a water-containing food in a microwave oven is formed of a tubular or bag-shaped moisture-permeable cellophane paper. 2. A wrapping material for wrapping a water-containing food when heated in a microwave oven is formed of a tubular or bag-shaped moisture-permeable cellophane paper, and at least a part of the tube or bag is formed. A food packaging material for a range heating, characterized in that an oil absorbing sheet is arranged. 3. The moisture-permeable cellophane paper has a diameter of 30 to 300.
The packaging material for a range heating according to claim 1 or 2, characterized in that the pores of µm are formed in a distributed manner with an opening ratio of 0.5% or less. 4. The tubular or bag-shaped moisture permeable cellophane paper is provided with a bonding portion, and the bonding strength of the bonding portion having a length of 5% or less is 1 kg / 15 mm or less. The packaging material for a range heating according to claim 1 or 2. 5. The oil-absorbent sheet is a bottom plate of a packaging material,
The food packaging material for a range heating according to claim 2, wherein at least an upper surface opening or the whole of the bottom plate is covered with the moisture permeable cellophane paper. 6. The oil absorbing sheet has a weight of 30 to 90.
g / m ² and its bulk density is 0.03 to 0.3 g
6. The food packaging material for range heating according to claim 2 or 5, which is mainly composed of cellulose fibers of / m ³ . 7. The food packaging material for range heating according to claim 6, wherein the cellulosic fibers are made of Kapok fibers, and the Kapock fibers are contained in an amount of 20 to 80% by weight based on the total amount. 8. A container containing a water-containing food to be heated in a microwave oven is closely adhered to and covered with cellophane, and the cellophane paper is provided with pores having a diameter of 30 to 300 μm. A microwave oven packaging body characterized by being covered with.