FI90224C - Method and apparatus for packing products that absorb carbon dioxide, in particular delicate foods - Google Patents

Description

1 90224

Method and apparatus for packaging carbon dioxide-absorbing products, in particular perishable food products - Forfarande och anordning for packning av products with absorberar koldioxid, isynnerhet omtåliga matvaror

The present invention relates to a method and apparatus for packaging a product capable of absorbing carbon dioxide in a flexible, product-enclosing package, the method comprising placing said product and a predetermined amount of carbon dioxide in a solid phase in said solid-containing package.

It is known that in order to improve the preservation of perishable foodstuffs which can absorb carbon dioxide, in particular meat products, these products are packaged by suitable devices which, before the product is sealed, change or completely change the also carbon dioxide (see e.g. US-A-2,955,045).

Said gradual absorption of carbon dioxide also causes a reduction in carbon dioxide in the space surrounding the product, thus creating a void in the package, which is disadvantaged by the collapse of the package if it is made of easily deformable material, as is usually the case for packages containing synthetic material.

In the case of products which can absorb; : large amounts of carbon dioxide, the compression of the package can cause the products in it to be crushed, deformed and, in some cases, liquid to be compressed, which makes the appearance of the product very unpleasant; . ·. si.

In view of the fact that these packaging methods:. primarily for food products, there is a strong problem in the field of void formation in the package, followed by a change in shape, as the package often constitutes a means of selling the product.

The absorption of carbon dioxide by the product further changes the gas ratios, reducing the carbon dioxide in the atmosphere in the package and limiting the possible shelf life of the product.

A change in the shape of the packaging may, in addition to the problems it causes to the appearance of the product, make consumer information, such as the expiry date of the product or other information normally printed directly on the package or on the sheets glued or placed inside the package, completely or partially illegible.

It is an object of the present invention to solve the above-mentioned problems by providing a method for packaging easily carbon-absorbent products, in particular perishable food products, which avoids or at least significantly reduces the change in shape of the package caused by the vacuum created after packaging.

Within the scope of the above object, it is an object of the invention to provide a method which easily improves the shelf life of carbon dioxide absorbing products and maintains the integrity of the product during packaging.

Another object of the invention is to provide a method which does not contaminate the product with substances which endanger health.

This object, as well as the other objects set out below, are achieved by a method for packaging carbon dioxide-absorbing products, in particular perishable food products, as defined in claim 1, as well as by a device, the characteristics of which appear from claim 11.

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The features and advantages of the invention will become apparent from the description of the method according to a preferred but not exclusive embodiment of the invention, which is illustrated by the non-limiting example of the accompanying drawings. In the drawings: * Figures 1-5 illustrate in order the different steps of the packaging method according to the invention; and Fig. 6 is a schematic side view of a packaging device for the automatic execution of the method according to the invention.

With particular reference to Figures 1-5, the method of the invention comprises a first step of placing product 1 or more products in a known package 2 made of, for example, a synthetic material (Figure 1) and a second step of introducing a predetermined amount of solid phase carbon dioxide into package 2. (Figure 2).

The package 2 is then sealed, for example by heat sealing, gluing or other known sealing method, in order to isolate the interior of the package from the ambient atmosphere.

The introduction of the carbon dioxide in the solid phase into the package 2 can, of course, precede or follow the insertion of the product 1 into it, or it can be simultaneous.

The amount of carbon dioxide fed to the package 2 is determined in advance according to how much the product can be absorbed after packaging, also taking into account the mechanical durability of the package 2 and the final product, for example by avoiding collapse of the package 2 for several days.

The amount of solid phase carbon dioxide fed to the package 2 can simply be determined based on absorption studies of the various products, as it has been found that most carbon dioxide absorbing products absorb up to 4,90224 of the potentially absorbable carbon dioxide within one hour, reaching equilibrium.

The carbon dioxide in the solid phase is introduced into the package 2 in the form of carbon dioxide ice cubes or tablets 3 of a predetermined weight so that they meet the absorption requirements of the product as described above.

Alternatively, the carbon dioxide in the solid phase can be introduced into the package 2 in the form of fine flakes of carbonic acid ("carbonated snow").

The interior of the package 2 can preferably be "purged" before sealing with a jet of an inert gas, for example nitrogen, which at least partially replaces the air inside the package 2.

The air in the package 2 can be completely replaced, if required, by a regulated atmosphere comprising, for example, a gas mixture containing mainly carbon dioxide and nitrogen, the package being sealed in a suitable chamber 4 of the resulting atmosphere, as in "

After sealing, the solid phase carbon dioxide placed in the package 2 sublimates slowly, pressurizing the interior of the package, while the product begins to absorb the carbon dioxide in the gas phase, gradually reducing the overpressure formed in the package 2 (Figure 4). A few hours after packaging, the pressure inside the package 2 equalizes and the package 2 takes on a shape that remains substantially unchanged for several days after packaging (Figure 5). For example, if the amount of CO2 in the solid phase placed in package 2, possibly replacing the atmosphere in package 2 with the amount of carbon dioxide introduced in the gas phase (if replacement has been arranged), is slightly greater than the amount of carbon required to balance the product. A gas mixture containing 2 carbon dioxide for up to several days after packaging, so that compression is also avoided with packages with very low xecan resistance or without their own shape, such as soft bags.

It should be noted that with the method according to the invention, unless complete replacement of the atmosphere inside the package 2 is required, both the step of introducing solid phase carbon into the package and the subsequent sealing of the package 2 in each case can take place by modification caused by sublimation of carbon dioxide in the solid phase.

Although the method according to the invention can also be carried out in a simple manner by successive manual operations, due to its simplicity, a device, generally indicated by reference numeral 10 in Fig. 6, can be used, said device comprising a known packaging system in which a conveyor element 11 is placed. , which are intended to contain the products 1. Said conveyor element 11 can move along a path which passes in order past the station 5 where the products 1 are placed in the packages 12 and past the closing station 13 where the packages 12 are closed by known devices. According to the invention, in the direction of travel of the conveyor element, a dosing device 14 is arranged before the closing station 13. a finely divided amount of carbonated ice on the product in the package, which is currently located below said nozzles.

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According to another embodiment, which has not been illustrated for the sake of simplicity, the dispensing device may also consist of a means for dispensing carbonated ice tablets, the tablets being placed in packages 12, such as a fine flaked carbonic acid.

The sealing station 13 can simply handle a known device which closes the open side of the packages 12, for example by heat-sealing them with the synthetic material 15 of the sheet.

If the atmosphere in the package 12 needs to be replaced, the sealing station 13 can be located inside the charged atmosphere chamber 16, which in a known manner contains a gas mixture, for example a mixture of carbon dioxide and nitrogen, as in known compressed atmosphere packaging devices.

If complete replacement of the atmosphere in the packages 12 is not required, partial replacement of the atmosphere in the packages 12 can be achieved by arranging an inert gas, e.g. for shower packs 12.

In practice, it has been found that the method according to the invention perfectly achieves the intended object, because due to the feeding of carbon dioxide in the solid phase, the amount of carbon dioxide absorbed by the product is compensated after packaging, and the the original shape of the packaging.

Another advantage, given the simple implementation of the method according to the invention, is that it can be used both in manual packaging methods and in automated packaging methods.

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Although the method according to the invention is intended in particular for the packaging and preservation of perishable food products, it can in any case also be used successfully for any other products which are sensitive to carbon dioxide and which have similar problems with packaging and product integrity. after.

The following is an example of how the invention can be applied to the application: a chicken weighing 700 g is placed in a silo with a volume of 2200 cm 3; - a compressed dry ice tablet with a density of 1 kg / dm3 and a weight of 0.8 g is also placed in a silo; - the atmosphere in the silo is replaced by a gas mixture comprising 50% carbon dioxide and 50% nitrogen at atmospheric pressure; and - the silo is closed.

After 12 to 16 hours, the pressure in the silo is equal to the pressure in the surrounding air, and the atmosphere in the silo comprises 50% carbon dioxide and 50% nitrogen.

The product, which is kept at a temperature of +1 ... + 3 ° C, remains unchanged for about 40-50 days.

The method thus formed can be modified and altered in many different ways, all of which fall within the scope of the inventive idea. In addition, all details can be replaced by technically equivalent elements.

Claims (15)

A method of packaging a product capable of absorbing carbon dioxide in a flexible, product-enclosing package, the method comprising placing said product (1) and a predetermined amount of solid phase carbon dioxide (3) in said package (s), enclosing that method further comprises enclosing said product and said solid phase carbon dioxide in said package, allowing said solid phase carbon dioxide to sublimate and at least partially be absorbed by said food product, and not enclosing said product in a package; in a compressed state. Process according to claim 1, characterized in that said carbon dioxide in the solid phase is a carbonic acid residue. Process according to claim 1, characterized in that said carbon dioxide in the solid phase is a carbonic acid residue in the form of fine flakes. Process according to Claim 1, characterized in that the process is carried out in a normal atmosphere. A method according to claim 1, characterized in that said package defines an interior space which is purged with a jet of inert gas before closing said package. Method according to Claim 1, characterized in that the package is sealed in a chamber (4) having a controlled atmosphere. 9 90224 A method according to claim 6, characterized in that said controlled atmosphere consists of a gas having at least one part of carbon dioxide a in the gas phase. A method according to claim 1, characterized in that said predetermined amount of carbon dioxide in the solid phase is selected according to the extent to which said product can absorb carbon dioxide. A method according to claim 1, characterized in that said package enclosing the product inside is closed in a chamber part having a controlled atmosphere, and in that said predetermined amount of carbon dioxide in the solid phase corresponds to the amount which said product is absorbed by said packaging the equilibrium state of said package is achieved in a package containing said product and the original gas mixture as introduced in the chamber having a controlled atmosphere during the sealing step. Method according to any one of the preceding claims, characterized in that said food product is a meat product. An apparatus (10) for packaging carbon dioxide-absorbing products, for carrying out a method according to any one of the preceding claims 1 to 10, which apparatus comprises a conveyor element (11) for packages receiving the products (1) to be packaged, said conveyor element being movable along a path passing sequentially past the station (5) where the products are placed in the packages and past the closing station (13) where said package is closed, characterized in that in the direction of movement of said conveyor element (11) before the closing station (13) comprises a dispensing device (14) for dispensing a predetermined amount of solid phase carbon dioxide into said packages. 10 90224 Device according to claim 11, characterized in that said closing station (13) is arranged in a chamber (16) containing a gas or gas mixtures, at least some of which are carbon dioxide. Device according to claim 11, characterized in that said dispensing device (14) comprises nozzles for dispensing carbon dioxide ice (carbon snow) formed into fine flakes. Device according to claim 11, characterized in that said dispensing device (14) comprises a device for dispensing tablets in carbonic acid. 15. A device according to any one of the preceding claims, further characterized in that the conveyor and working element (11) in the running direction of the before-mentioned phase hii1idioksidin kiinteåsså the metering device (14) is jårjestetty inert gas distribution system (17) of said packaging ent-side rinsing. η 90224