JP2714701B2 - Edible film - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an edible film having excellent blocking resistance and good heat sealability.

(Prior art) In general, instant noodles, powdered soup of cup noodles, seasoning oils, dried vegetables, etc. are used in various packaging materials such as aluminum-polyethylene laminates, cellophane-polyethylene laminates and various plastic films to maintain quality and form. It is enclosed.

In addition, in the case of cup noodles, ingredients such as dried vegetables may be contained without packaging.

However, if powdered soup, seasoning oil, dried vegetables, etc. are contained in a packaged state, it is necessary not only to break the packaging and take out the contents at the time of cooking, but it is not only complicated, but also In the case of a liquid, there is a problem that it is easy to spill when breaking the package.

In addition, in the case of non-packaged products, not only is the problem that the fragrance is easily released and quality maintenance becomes difficult, but also there is a problem in maintaining the form. There was a problem that the presence of the ingredients could not be confirmed when the lid was migrated downward and the cup noodle was opened.

As a method of solving such a problem, if the contents are wrapped in an edible film, the contents and the form can be maintained during transportation and storage, so that the quality and form can be maintained. In some cases, it is not necessary to break the package if hot water is used as it is during cooking, so there is a need for packaging with such a material.

Such materials must have sufficient film strength to prevent the contents from spilling when the package is broken during handling, and must be heat-sealable from the viewpoint of packaging workability. Although there is a demand, conventionally known edible films containing a water-soluble polysaccharide or a water-soluble protein as a main component are excellent in edibility and oxygen barrier properties, but have insufficient heat sealing properties and ordinary heat. Under the sealing conditions, heat sealing is not possible, or even if heat sealing is possible, the heat sealing strength is insufficient, and if the heat sealing conditions are strict, the film will shrink or break. was there.

A method of uniformly mixing and kneading amylose, an alkali metal salt of casein and a low-molecular-weight plasticizer to form a film in order to improve the heat sealing property of the edible film (see JP-A-51-112533), collagen A method of immersing the film in a mixture of gelatin or glue and a plasticizer or applying the mixture (see JP-A-52-11280), a method of laminating a polysaccharide with gum arabic, pullulan, starch or gelatin (particularly, Japanese Unexamined Patent Publication No. Sho 60-76336) and a method of incorporating a solid fat into an edible film (JP-A-63-59855).
And the like) have been proposed.

(Problems to be Solved by the Invention) However, those obtained by uniformly mixing and kneading amylose, an alkali metal salt of casein and a low molecular weight plasticizer, those obtained by laminating a polysaccharide with gum arabic, pullulan or starch,
All of the edible films containing solid fat do not yet have sufficient heat-sealing properties, and those obtained by laminating a collagen film or a polysaccharide with gelatin significantly improve the heat-sealing strength. There is a problem that the blocking property between the films is remarkably manifested due to the presence of, and the handling of the film becomes difficult.

Thus, the present inventors have previously proposed a method of solving these problems by laminating a layer mainly composed of a water-soluble polysaccharide and a layer mainly composed of an alkali metal salt of casein, thereby achieving excellent heat sealing properties. Found that an edible film having excellent blocking resistance can be obtained, and proposed such a film (Japanese Patent Application No. 1-132356). However, the alkali metal salt of casein has a characteristic milk-like odor. It has been found that there is a problem that the decay rate of the aqueous solution of the alkali metal point of casein is high.

(Means for Solving the Problems) In view of such a situation, the present inventors have provided a performance as a packaging material, have a good heat sealing property, and have an excellent odorless blocking resistance. As a result of intensive studies on the edible film, the present invention has been achieved.

That is, the gist of the present invention is an edible film in which a layer mainly composed of soy protein or soy protein and gelatin is formed on at least one surface of a film mainly composed of a water-soluble polysaccharide.

Examples of the water-soluble polysaccharide used in the present invention include alginic acid and salts thereof, furceleran, carrageenan,
Agar, pectin, tamarind gum, xanthan gum, guar gum, cod gum, locust bean gum, arabinogalactan, gum arabic, pullulan, chitosan, starch, dextrin, edible water-soluble cellulose derivatives and mixtures of two or more of these Although it is possible, from the viewpoint of film forming properties, film physical properties, etc., those containing at least one selected from alginic acid and salts thereof, furceleran, carrageenan, and agar are preferable, and those containing carrageenan as a main component, that is, constituent polysaccharides More preferably, 50% or more of the carrageenan is composed of carrageenan.

Further, the film containing a water-soluble polysaccharide as a main component preferably contains a polyhydric alcohol in order to give flexibility to the film. Examples of such a polyhydric alcohol include ethylene glycol, propylene glycol, glycerin and Examples include oligosaccharides such as sorbitol, mannitol, maltitol, xylitol, reduced starch saccharified sugar alcohol, glucose, fructose, galactose, xylose sugar monosaccharide, saccharose, maltose, lactose and other disaccharides, and starch degradation products. . The content of this polyhydric alcohol is 0.1 part per 1 part by weight of the water-soluble polysaccharide.
It is preferably from 2 to 1 part by weight. In addition, a water-soluble protein, an edible dye, and the like may be added to the film containing the water-soluble polysaccharide as a main component as long as the amount is smaller than that of the polysaccharide.

In the edible film of the present invention, a layer containing soy protein or soy protein and gelatin as main components is formed on at least one surface of the film.

Even those containing only soybean protein as the main component or those containing soybean protein and gelatin as the main components give films excellent in heat sealability and blocking resistance,
Comparing the two, the former has a feature of being more excellent in blocking resistance, and the latter has a feature of being more excellent in heat sealability. In the latter case, if the ratio of gelatin to the total amount of soybean protein and gelatin is 80% by weight or less, blocking resistance can be greatly improved as compared with the case of 100% gelatin, and Although it depends on the request, it is possible to impart a level of blocking resistance that does not cause a problem in practical use. The proportion of this gelatin is preferably at most 70%, more preferably at most 60% by weight.

The soybean protein used in the present invention is a protein obtained by separating and concentrating these contained proteins from soybean seeds or defatted products thereof to increase the protein content, and generally accounts for the whole protein derived from the main raw material. Preferably, the proportion is higher than 50% by weight, but the protein content is not limited to a specific value.

As the soybean protein used in the present invention, a commercially available soybean-derived powder protein can be used.

When gelatin is also used in the present invention, any grade of gelatin can be used as long as it is edible, and generally commercially available powdered gelatin can be suitably used.

The soybean protein or a layer containing soybean protein and gelatin as main components may also contain additives such as food coloring.

The layer containing soybean protein or soybean protein and gelatin as main components imparts heat sealing property and anti-blocking property. Absent. Also, this layer may be formed on both sides of the film, but when used for heat sealing with an automatic heat sealer, it should be formed on only one side from the viewpoint of heat sealing workability. Is preferred.

Although the thickness of the film of the present invention is not particularly limited, it is preferably 10 to 100 μm for the purpose of packaging, and the layer mainly containing soybean protein or soybean protein and gelatin is mainly heated. Considering that the purpose is to impart sealing properties and anti-blocking properties, the thickness is preferably 0.1 to 10 μm, and even if the thickness is further increased, there is no added benefit of increasing the thickness.

The edible film of the present invention preferably has a water content of 25% or less.

With the above configuration, an odorless edible film having excellent strength properties, dissolving in hot water, having heat sealing properties, and having excellent blocking resistance is obtained.

The film of the present invention is preferably a water-soluble polysaccharide in water containing polyhydric alcohol, the concentration of the polysaccharide is 20% by weight or less,
More preferably, it is dissolved so as to be 10% by weight or less, a film is formed from this aqueous solution, and then dried so that the water content is 25% or less, preferably 20% by weight or less. In dissolving the polysaccharide in water or an aqueous solution of polyhydric alcohol, it is preferable to heat the mixture to 70 ° C. or higher to promote the dissolution. After defoaming the solution thus obtained, it is cast on a support such as a drum, a steel belt, a glass fabric impregnated with polytetrafluoroethylene, various plastic films or sheets so as to have a predetermined thickness, and electric heating and hot air from the support side are applied. Alternatively, a film containing a polysaccharide as a main component is obtained by drying by infrared radiation or the like.

The formation of a layer containing soybean protein as a main component can be obtained by applying an aqueous soybean protein solution or a solution obtained by further dissolving gelatin to the thus obtained film, or by immersing this film in this solution and then drying. Alternatively, a film may be prepared from an aqueous solution containing soybean protein or further gelatin, and this may be laminated with a film containing a polysaccharide as a main component and adhered with water, an edible adhesive or heat.

(Examples) Hereinafter, the present invention will be described in more detail using examples.

In the following, “parts” means “parts by weight” unless otherwise specified.

 In addition, each evaluation was measured at room temperature as follows.

Heat seal strength: Fuji Impulse Policyr 210E
Heat sealing is performed with the mold and scales 1 to 6, and JIS Z0238
It measured according to.

Blocking property: 1.5 cm width 10c from a film in which a layer containing soybean protein as a main component is formed on at least one entire surface
Cut out two m-length samples and overlap them so that the layers mainly composed of soy protein are in contact with each other. Half of the area (1.5 cm wide, 5 cm long) from one side of the laminated film
So as to prevent blocking Nde inserted the paper, while 20 ° C. The overlapping film was pressurized with 70 g / cm ² 65
After leaving for 24 ± 1 hour in an atmosphere of% RH, the sample was taken out, peeled off at a tensile speed of 5 cm / min, and the 180 ° peel strength at 1.5 cm width was measured.

Smell sensory test: A sample of 10cm x 10cm was cut out from the film, and five panelists smelled the smell of each sample.
The sample which did not feel the smell at all was ranked as 0 and ranked as follows.

0-1 Odorless (described as "none" in Table 1) 2-3 Slight odor (described as "fine" in Table 1) 4-5 Odor present (described as "present" in Table 1) Example 1, Comparative Example 1 7 parts of potassium potassium carrageenan was dispersed in a mixture of 4 parts of glycerin and 100 parts of water, heated to 85 ° C. and stirred for 60 minutes to dissolve carrageenan. The solution thus obtained was degassed under reduced pressure while maintaining the temperature at 85 ° C., then cast on a stainless steel flat plate and dried with hot air to obtain a film having a water content of 15% and a thickness of 48 μm. The weight ratio of polysaccharide to polyhydric alcohol was 7: 4. Next, a 5.0% aqueous solution of soybean protein (Fujipro R, manufactured by Fuji Oil Co., Ltd.) was applied to the entire surface of the film (only one surface), and dried with hot air again to obtain a 15% moisture, 49 μm thick film. A film with excellent properties was obtained. Table 1 shows the measurement results of the heat seal strength and the blocking property of this film, and the results of the sensory test for odor.

For comparison, the physical properties of the film before the application of the aqueous soybean protein solution were measured in the same manner (Comparative Example 1). The results are also shown in Table 1.

Example 2 2.5% of soybean protein (Fujipro R) and gelatin (S-4,
After applying a 2.5% mixed aqueous solution of Nitta Gelatin Co., Ltd.
The film was dried again with hot air to obtain a film having a moisture content of 15% and a thickness of 49 μm and having excellent strength characteristics. This film was used to evaluate in the same manner as in Example 1. Table 1 shows the results.

Example 3, Comparative Example 2 3 parts of copper potassium carrageenan and 1 part of purified locust bean gum are dispersed in a mixture of 2 parts of glycerin, 1 part of sorbitol and 100 parts of water, and the mixture is heated to 85 ° C. and stirred and dissolved for 60 minutes. did. A film having a moisture content of 15% and a thickness of 47 μm was obtained in the same manner as in Example 1 except that this solution was used. After applying a soybean protein aqueous solution having a concentration of 3.0% to one surface of the film, the film was dried again with hot air to obtain a film excellent in strength characteristics having a water content of 15% and a thickness of 47.6 μm. The physical properties of this film were evaluated in the same manner as in Example 1. For comparison, the film before the application of the aqueous soybean protein solution (Comparative Example 2) was also evaluated. Table 1 shows the results.

Comparative Examples 3 to 7 Each of the films prepared in Example 1 before application of the soybean protein aqueous solution had a 5% concentration of gelatin (Comparative Example 3), pullulan (Comparative Example 4), gum arabic (Comparative Example 5), and corn starch (Comparative Example). 6) and sodium caseinate (Comparative Example 7)
Was applied and then dried with hot air, and the physical properties of the obtained film were evaluated in the same manner as in Example 1. The result is
It is shown in the table.

(Effects of the Invention) The film of the present invention is edible, has heat-sealing properties and anti-blocking properties, and has the strength characteristics required for bags for enclosing ingredients such as ramen and seasonings, so that it can be used for various instants. It is useful as a food packaging material.

Claims (1)

(57) [Claims] An edible film comprising a film containing a water-soluble polysaccharide as a main component and a layer mainly containing a soy protein or a soy protein and gelatin formed on at least one surface of the film.