JPS6019982B2 - Manufacturing method of soybean protein coating film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a soybean protein coating film using a synthetic resin film as a base material and particularly suitable for packaging processed meat foods such as ham, sausage, kamaboko, and similar products thereof.

Generally, when manufacturing processed meat foods using synthetic resin films, the adhesion between the synthetic resin film and the food surface (so-called "
The problem is that J.'s performance is poor.

These food materials have a relatively high moisture content and are subjected to heat treatment after packaging, so if the adhesion is poor, a so-called "hydrolysis" phenomenon occurs in which water is released between the film and the food surface. It is generally accepted that syneresis not only impairs the appearance and freshness of the product, but also causes spoilage, and is undesirable from a sanitary standpoint. Therefore, when packaging processed meat foods using synthetic resin film, mechanical treatments such as corona discharge treatment, chemical treatment, or sandblasting are applied to improve the adhesion between the film surface and the food material. This improves syneresis and prevents syneresis. However, even these treatments cannot completely prevent syneresis, and it is especially difficult to deal with changes in adhesion caused by changes in the composition of processed meat foods, and even products manufactured under optimal conditions often suffer from syneresis. phenomenon was observed. Under these circumstances, attempts have been made to coat cellophane substrates with edible substances that have relatively stable adhesion to food materials in order to improve the adhesion as a whole.

For example, special public floor 36-1 & 481, Mochiseki Sho 52-66, 6
60 and the fin face Sho 51-80, 25 developed by the present inventors.
5 (Special Publication No. 59-2107) and Hakama Akisho 52-1 Matsu,
255 (Samurai Seki Sho 54-55752) etc.
When cellophane is used as a base material, unlike the case of synthetic resin film, it has excellent adhesion to edible substances, and it provides adhesion that can resist swelling of the base material mainly due to absorption of moisture from food materials after packaging. In this case, the occurrence of water separation can be prevented and the objective can be achieved relatively easily. However, in the case of cellophane, it does not show thermal shrinkage even if food materials are heat-treated after packaging; on the contrary, cellophane exhibits bidirectional expansion by absorbing moisture in the food materials, and also has high water permeability, so it cannot be used alone. Because of this, it is difficult to use in processed meat foods, and in many cases double packaging is used in which the outer layer is further wrapped with a heat-shrinkable synthetic resin film. In view of this situation, the present inventor has previously attempted to develop a film with strong adhesion by forming unevenness made of inorganic fine powder on the surface of a packaging film, as shown in Tokubuta 12,816. Successful.

As a result of further research, the inventor of the present invention found that, contrary to the general belief that sufficient adhesion cannot be obtained even if hydrophilic edible substances such as proteins and polysaccharides are applied to a synthetic resin film with a hydrophobic surface, It was discovered that by applying a coating agent containing heat-coagulable soybean protein to a synthetic resin film whose surface has been activated to a certain degree, a material suitable as a packaging material for such processed meat foods can be obtained. Ta. That is, at least 40% by solid weight of soybean protein and other proteins and/or proteins are added to a synthetic resin film that is substantially active against soybean protein.
Alternatively, a soybean protein coating film obtained by applying an aqueous dispersion containing polysaccharides and adding polyhydric alcohol as a plasticizer to form a film containing soybean protein on a synthetic resin film can be used for processed meat foods. It is used as packaging material.

There is no occurrence of syneresis at all in the products in which processed meat foods are packaged and heat-treated using such a soybean protein coating film obtained by the present invention, and when the synthetic resin film is removed from the product, there is no resistance to peeling. I can feel the resistance.
When carrying out the present invention by further activating the synthetic film as described below, when the synthetic resin film is peeled off from the product, the soybean protein film is not peeled off from the synthetic resin film, but is peeled off in the form of peeling off the product surface. The synthetic resin film and the soybean protein-containing film adhere firmly to the extent that The main purpose of the soybean protein coating film of the present invention is as a packaging material for processed meat foods, which has an excellent effect of preventing syneresis especially when heat-treated after packaging. Of course, this film can also be used for packaging foods other than processed meat foods, and is effective when the purpose is to avoid direct contact between food and the synthetic resin film. The synthetic resin film used in the present invention is not limited in type as long as it is suitable for food hygiene and can be processed to become substantially active against soybean protein, but it can be used for packaging processed meat foods. If you only want to
Generally, a film is required to have excellent heat shrinkability and also excellent gas impermeability (gas barrier properties).

For example, vinyl chloride/vinylidene chloride copolymer films (product name: Saran, etc.), composite films of polyamide and polyethylene (product name: Ponyl), films produced by hydrolyzing ethylene vinyl acetate copolymer (product name: Burl film), etc. are suitable as synthetic resin films for packaging processed meat foods.In the present invention, such various films are treated to become substantially active against soybean protein.The activity is imparted by corona discharge. treatment, flame treatment, chemical treatment with potassium permanganate or potassium dichromate, mechanical treatment such as sandblasting or buffing, or a combination thereof.These treatments can improve the wettability index of the surface of the synthetic resin film. (JISK6768-1
971. (same below) to 3 groups e/skin or higher. In particular, in the case of the present invention, which is mainly intended as a packaging material for processed meat foods, a heat-shrinkable film is usually used, and after the food material is packaged, it is subjected to heat treatment accompanied by heat shrinkage.
Synthetic resin films and soybean protein-containing films, which have different heat shrinkability, tend to peel off. It is necessary to provide adhesion to a degree that can completely resist this peeling tendency, and in this case, it is particularly preferable that the wetting index is 4 or more. Wetness index 42
When using a synthetic resin film that has been treated to be more than dyne/skin, the adhesion between the film and the soybean protein-containing film is further improved, and when the synthetic resin film is peeled off from the product, the soybean protein-containing film is removed from the synthetic resin film. It is peeled off together with the film.

This improves adhesion and eliminates any contact between the synthetic resin film and the portion to be eaten, which may be preferred from a sanitary standpoint. In the present invention, an aqueous dispersion containing soybean protein is applied to a synthetic resin film that has been subjected to an activation treatment. Combined with sugars (hereinafter referred to as proteins)
It is obtained by further adding polyhydric alcohol as a plasticizer.

It is necessary to contain at least 40% of soybean protein based on the weight of soybean proteins; if it is less than 40%, the gelation of the coating film will be inhibited, the strength of the soybean protein-containing film will be reduced, and the moisture content in the food material will be reduced. This is undesirable since the film may become viscous when used as a processed meat food. The soybean protein used in the present invention is preferably isolated soybean protein with a soybean protein purity of 60% or more, and may be in the form of a liquid, paste, or dry powder. These soybean proteins may be used alone or in combination with proteins such as casein, collagen, egg white, and gelatin, and/or various starches or edible cellulose derivatives. These proteins are used to prepare an aqueous dispersion, and the aqueous dispersion is adjusted in consideration of viscosity conditions that affect operability.

In other words, it is preferable to have a pH in the range of 6 to 10, which is suitable for the dispersibility of soybean protein, and a viscosity of 10 to 500 poise (20qOB type viscometer). By using a dispersion, the viscosity is limited.
If the viscosity is less than 10 poise, the continuity of the coating film may be disturbed, and if it is more than 500 poise, the workability of the coating process will be significantly reduced, which is not preferred. As the plasticizer, edible polyhydric alcohols such as glycerin, sorbitol, mannitol, and propylene glycol are preferred. These may be used alone or in combination at a rate of 1% per weight of protein.
It is preferable to add 0 to 40%. If it is less than 10%, it is difficult to impart sufficient flexibility to the coating film, and if it is more than 40%, the coating film becomes sticky, which is not preferable.

Furthermore, it is possible to add edible dyes, flavors, and seasonings to the aqueous dispersion of the present invention depending on the purpose. In particular, when used for packaging processed meat foods, the addition of edible dyes may be required. many.

The aqueous dispersion thus prepared is applied to a synthetic resin film by coating, spraying or dipping.

The coating is dried and applied to a thickness of about 1 to 100 µm. When the number of ridges exceeds 100, the bending resistance of the coating film increases and the adhesion between the synthetic resin film and the coating film tends to be lost due to bending effects caused by various handling, which is not preferable.

The applied coating is then dried. The drying temperature is desirably at a level that avoids a high degree of heat denaturation of soybean protein, and when a heat-shrinkable synthetic resin film is used, it is desirably a temperature that does not cause heat shrinkage. Therefore, when used as a packaging material for processed meat foods, it is best to dry at around 60 oz, but even for synthetic resin films with little heat shrinkage, a temperature of 80 q or lower is usually appropriate. The film obtained as described above is usually formed into a tube shape with the coating film on the inside.

The formed film is filled with raw materials for processed meat foods such as ham, sausage or kamaboko, and after being filled, both ends are streaked and heat treated to a temperature of about 8 pi. Due to this heat treatment, syneresis occurs between the food material and the film in conventional packaging materials, but with the film of the present invention, there is no syneresis at all.
It also achieved good results in a storage test in which it was stored in a 500°C refrigerator for one month. The present invention will be explained in more detail below with reference to Examples.

Example 1 A vinyl chloride vinylidene chloride copolymer film (product name: Saran,
(manufactured by Asahi Dow Co., Ltd.) was continuously fed at a rate of 30 minutes. On the other hand, the acid pillow curd from soy milk obtained by extracting defatted soybeans is
A soybean protein-containing aqueous dispersion is prepared, which is adjusted to H7 and consists of 26 parts of heat-denatured soybean protein, 7 parts of glycerin, and 167 parts of water. The obtained aqueous dispersion was spread on the film for about 10 minutes.
The soybean protein coated film was coated to the final thickness and then completely dried through a drying process of 6000 ml of hot air. The soy protein-containing film that adheres to the film after drying is 1.6
It was thick. Using the obtained soybean protein coating film, high frequency welding was performed with the soybean protein-containing film on the inside to create a cylinder with a diameter of 3 mm/side.

On the other hand, the above cylinder was filled with sausage paste obtained by grinding 1.7 k9 of pork, 30 k of salt, 60 k of starch and 300 k of ice, and the two ends were tied to a length of about 3 mm. , 8
Heat treated at 0x0 for 5 minutes.

When the appearance was observed after cooling, no syneresis was observed between the Saran film and the surface of the contents, and when the Saran film was peeled off, it was peeled off with strong resistance while the soybean protein-containing film remained on the film side. It was done. Example 2
Wetting index 4 Kohada e/Gaga corona discharge machining thickness 20
A French 2-mall stretched polypropylene film was pasted on a glass plate, and 25 parts of soy protein powder "Fuji Pro R" (manufactured by Fuji Oil Co., Ltd.), 5 parts of corn starch, and 5 parts of corn starch were added.

A soybean protein-containing aqueous dispersion consisting of 6 parts of pyrene glycol and 164 parts of water was adjusted to pH 9 and coated on the polypropylene film to a thickness of 30 mm. After coating, it was dried for 1 minute in a hot air dryer at 60 oo, and then the polyprene film was peeled off from the glass plate to obtain a soybean protein coated film. The thickness of the soybean protein-containing film of this film is 5.5
It was Buddha. The sausage raw material prepared in the same manner as in Example 1 was packaged with the coated side of the film inside, and the five powders were treated with boiling water at 80 qo. When the appearance of the obtained sausage was observed, no syneresis was observed, and no syneresis occurred even after storage at 500°C for 30 days.

When the outer skin (polypropylene film) of the sausage was peeled off after being stored for 30 days, it was peeled off with a strong sense of resistance, and the soybean protein-containing film was peeled off together with the outer skin.

Example 3 Soybean protein with a pH of 8 was isolated using acid pillow curd from soymilk obtained by extracting defatted soybeans, consisting of 21 parts of soybean protein, 5 parts of casein, 7 parts of glycerin, 5 parts of food coloring red No. 3, and 162 parts of water. An aqueous dispersion is obtained.

This liquid was coated on a polyethylene film having a thickness of 40A, which had been subjected to corona discharge machining on a yne/arc with a wetting index of 4, in the same manner as in Example 1, and sausages were prepared on the same machine. When the appearance of the obtained sausage was observed, no syneresis was observed, and when the outer skin (polyethylene film) was peeled off, it peeled off with some resistance, but the soybean protein-containing film separated from the outer skin and adhered to the surface of the sausage. was. The sausage was surrounded by a red gel-like film and had a shiny surface. Example 4 Example 2 was prepared by corona discharge machining using an unstretched polyethylene film with a wettability index of 3/3 and a thickness of 30 μm.
A soybean protein coated film was obtained in the same manner as above.

This film had resistance to bending operations in a dry state, and the soybean protein-containing film did not fall off in five repeated 360 degree bending tests. On the other hand, 1 piece of walleye cod,
After molding, a kamaboko raw material paste obtained by mixing and grinding 800 min of starch, 45 min of salt, and 500 min of water is packaged with the film surface facing inside.

After packaging, the mixture was left at 30°C for 1 hour, and then treated with 85°C boiling water for 20 minutes to obtain kamaboko. The resulting fish cake was slightly less firm than the sausage of Example 2, but no syneresis was observed.

Claims (1)

[Scope of Claims] 1 A synthetic resin film having substantial activity against soybean protein is blended with at least 40% by solid weight of soybean protein and other proteins and/or polysaccharides (hereinafter referred to as proteins). ) and further coated with an aqueous dispersion containing polyhydric alcohol as a plasticizer to form a film containing soy protein on the surface of the synthetic resin film, which is suitable for packaging processed meat foods. Method for producing protein coating film. 2. The method according to claim 1, wherein the other protein is casein, collagen, egg white and/or gelatin. 3. The method according to claim 1, wherein the polysaccharide is a starch and/or a cellulose derivative. 4 Add polyhydric alcohol to 10 to 40% of the weight of protein.
% of the method according to claim 1. 5. The method according to claim 1, wherein the polyhydric alcohol is glycerin, sorbitol, mannite and/or propylene glycol. 6. The method according to claim 1, wherein the aqueous dispersion has a viscosity of 10 to 500 poise. 7. The method according to claim 1, wherein the synthetic resin film has heat shrinkability. 8 The coating surface of the synthetic resin film has a wettability index of 38 dyn.
The method according to claim 1, which has an activity of e/cm or more. 9. The method according to claim 1, wherein the soybean protein coating film is coated so that the coating film has an average thickness of 1 to 100 μm.