JPH03258260A - High pressure sterilization - Google Patents

Abstract

PURPOSE:To make it possible to sterilize a content filled in a package without being accompanied with deterioration of a metal deposition layer of the package by a method wherein the package is provided with a laminated base having an outer layer film, a metal deposition layer and a heat-sealable film provided so as to coat the metal deposition layer and pressing is performed at a specified temp. CONSTITUTION:A bag pouch 1 is formed by facing a pair of laminated bases 2 and heat-sealing the periphery. The laminated base 2 has a structure laminating an outer layer film 3, a metal deposition layer 4 and a heat-sealable film 5 in this order. As the outer layer 5, a polyamide film such as a nylon 6 film is used. As the metal deposition layer 4, aluminum is made into a film on the base plastic film 3 by means of vapor deposition. As the heat-sealable film 5, a polyolefin film such as polyethylene film is used. In addition, as the high pressure sterilization condition, the temp. of a pressurizing medium is 80 deg.C or lower. As it is unnecessary to heat the package at a high temp. like this, steam permeability and oxygen permeability of the outer layer film and heat-sealable film constituting the package are kept under a good condition free from a possibility that the metal-deposited layer formed between films is oxidized and deteriorated.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a high-pressure sterilization method, and in particular to a method for sterilizing the contents filled in a package without deteriorating the metal-deposited layer of the package. Regarding high-pressure sterilization methods that can be used.

[Conventional technology]

BACKGROUND ART Foods, beverages, pharmaceuticals, etc. have traditionally been distributed in various packages, but from the viewpoint of hygiene and preservation, they have been required to be sterilized. In order to sterilize the contents filled and held in a package, there is a method of filling the sterilized package with contents that have been sterilized in advance.

However, in addition to sterilizing the contents and packaging, this method also
It is necessary to maintain the manufacturing equipment and the manufacturing environment in a constant sterile state, resulting in a problem of high manufacturing costs. For this reason, a method has been developed to sterilize a sealed package by heating and pressurizing it as it is. In recent years, the production of retort pouches, etc., which are made completely sterile by putting cooked food, etc. into a bag and sealing it and sterilizing it by heat and pressure in a retort (pressurized steam oven) has increased significantly. There is. The package used in such a sterilization method needs to have barrier properties against gas and water. For packaging bodies that require light-shielding properties as well as barrier properties, a laminated substrate is usually constructed in which, for example, an aluminum foil as a barrier layer is sandwiched between a polyester film as an outer layer film and a polyethylene film as a heat-sealable film. It is used.

[Problem to be solved by the invention]

However, packaging bodies using aluminum foil have a problem in that manufacturing costs are high.

On the other hand, focusing on the fact that an aluminum vapor-deposited layer of a predetermined thickness can provide barrier properties equivalent to aluminum foil,
It has been attempted to reduce manufacturing costs by forming an aluminum vapor deposited layer instead of aluminum foil. However, during pressure heat sterilization in a retort, the package was heated to a high temperature (1
20℃) Because it is exposed to pressurized conditions (several kgl/alf), the water vapor permeability and oxygen permeability of heat-sealable films such as polyethylene films increase and the aluminum layer is oxidized, resulting in whitening phenomenon and a decrease in barrier properties. There was a problem that this occurred.

The present invention was devised in view of the above circumstances, and aims to provide a high-pressure sterilization method that can sterilize the contents filled in a package without deteriorating the metal vapor deposited layer of the package. purpose.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention has been developed by pressurizing a package having barrier properties against gas and water, which is hermetically filled with contents, through a pressurizing medium in a pressurizing device, thereby separating the contents and the package. In the high-pressure sterilization method for sterilizing, the package includes a laminated substrate having an outer film, a metal vapor deposition layer, and a heat sealable film provided to cover the metal vapor deposition layer, and the pressurization is 80° C. or less. It is designed to be carried out at a temperature of

[Effect]

When the sealed package filled with contents is pressurized in a pressurized medium, high pressure is applied to the contents through the package, effectively sterilizing the contents and the package. is 8
Since the temperature is set at 0°C or lower, there is almost no change in the water vapor permeability and oxygen permeability of both the outer layer film and the heat sealable film, and therefore the metal vapor deposited layer formed between the films is The contents are sterilized without being oxidized and deteriorated.

〔Example〕

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

FIG. 1 is a perspective view of a bag pouch, which is a package used in the present invention. In FIG. 1, a bag pouch 1 is formed by placing a pair of laminated substrates 2 facing each other and heat sealing their peripheries. FIG. 2 is a diagram showing the cross-sectional structure of the above-described laminated substrate 2, and the laminated substrate 2 has a structure in which an outer film 3, a metal vapor deposited layer 4, and a heat-sealable film 5 are laminated thereon.

The bag pouch 1 is formed by heat-sealing the heat-sealable films 5 of a set of laminated substrates 2 so as to face each other.

As the outer layer film 3, polyamide films such as nylon 6 films, polyethylene terephthalate films (PET), polycarbonate films (PC), etc., which have excellent heat resistance, transparency, toughness, etc., can be used. Further, as the outer layer film 3, in addition to using each of the above-mentioned films alone, a laminated film having a heat-sealable film such as a polyethylene film as the outermost layer can also be used. The thickness of the outer layer film 3 can be determined as appropriate depending on the shape of the package, the type of contents, the method of use, etc., and is usually about 9 to 60 μm.

The metal vapor deposition layer 4 is usually formed by forming aluminum onto the base plastic film 3 by a known vapor deposition method. The thickness of this metal vapor deposited layer 4 is 200 to 800, preferably 300 to 70, considering gas barrier properties.
Approximately 0 people.

The heat sealable film 5 has heat sealability, strength,
Polyolefin films such as polyethylene film (PE) and polypropylene film (PP) can be used from the viewpoint of oil resistance and the like. The thickness of such a heat-sealable film 5 is about 10 to 100 μm. Lamination of the heat-sealable film 5 and the outer layer film 3 via the metal vapor deposited layer 4 can be performed by a known lamination method such as a dry lamination method.

The above-mentioned bag pouch 1 is formed by sealing the three sides and filling the contents, and then sealing the opening.

The contents to which the present invention can be applied include various beverages, foods, medicines, soy sauce, sauces containing solids, seasonings such as sauces, seasonings, and dressings, cosmetics, seasoning fruit juices such as yuzu, kabosu, and sudachi. etc.

In the present invention, various known high-pressure sterilization devices such as a device using a reciprocating pump can be used. Further, the pressurizing medium can be appropriately selected from among water, silicone oil, etc. depending on the type of contents, the method of using the package, etc.

In addition, the high pressure sterilization conditions in the present invention include a pressure of 1000
kgfla! or more, preferably 3000 to 5000
kgI/cd, and the temperature of the pressurizing medium is 80°C or less, preferably about 0°C to 60°C.

As described above, in the present invention, there is no need to heat the package to a high temperature, so the water vapor permeability and oxygen permeability of the outer layer film and the heat-sealable film constituting the package are maintained in a good state, and the The contents can be sterilized without the formed metal vapor deposition layer being oxidized and deteriorating. Furthermore, the quality of the contents does not deteriorate, and the texture and nutrients do not deteriorate.

Further, the pressurization time is preferably about 3 seconds to 60 minutes, and the pressure may be applied continuously or intermittently within this time. When pressurizing intermittently, the time for one pressurization is preferably about 3 seconds to 30 minutes, the time for one depressurization is preferably about 2 seconds to 10 minutes, and the pressure during depressurization is 1000 k
It is preferable that it is less than gl/al. By applying pressure intermittently in this way, even higher sterilization effects can be obtained.

Experimental Example After putting soup containing solids into the bag pouch shown in Figure 1 and sealing it, 3000 kg1/c was placed in still water at 60°C.
ffl, high-pressure sterilization was performed for 20 minutes.

Here, as the outer layer film, a laminated film in which a PE film (20 μm) and a PET film (12 μm) were laminated was used. Aluminum is vacuum-deposited on the PET film surface of this outer layer film to a thickness of 500 mm,
A bag was formed using a laminated substrate in which a 50 μm PE film was laminated as a heat-sealable film on this aluminum vapor-deposited layer. After high-pressure sterilization, the bag was left in an environment of 5℃ for 2 weeks, and after bathing in hot water for 5 minutes, the condition of the bag pouch was observed, but no leakage, destruction, or whitening of the aluminum vapor deposition layer was observed. I opened the package and examined the contents, but
No deterioration of the soup occurred.

〔Effect of the invention〕

As detailed above, according to the present invention, there is no need to heat the package to a high temperature, so the water vapor permeability and oxygen permeability of the outer layer film and the heat-sealable film constituting the package can be maintained in good conditions. , the contents can be sterilized without the metal vapor deposited layer formed between the films being oxidized and deteriorated, and the contents do not deteriorate in quality or deteriorate in texture or nutrients. It is played.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a bag pouch, which is a packaging body used in the present invention, and FIG. 2 is a sectional view of a laminated substrate used in the bag pouch of FIG. 1. DESCRIPTION OF SYMBOLS 1... Bag pouch, 2... Laminated base, 3... Outer layer film, 4... Metal vapor deposition layer, 5... Heat-sealable film.

Claims (1)

[Scope of Claims] 1. High pressure for sterilizing the contents and the package by pressurizing the package with gas and water barrier properties in a pressurizing device via a pressurizing medium. In the sterilization method, the package includes a laminated base having an outer film, a metallized layer, and a heat-sealable film provided to cover the metallized layer, and the pressurization is performed at a temperature of 80° C. or lower. A high-pressure sterilization method characterized by 2. Claim 1, wherein the pressurized medium is water.
High pressure sterilization method as described.