DE60120763T2 - HEATABLE FOOD PACKAGE WITH VENTILATOR - Google Patents

Abstract

Device (1) for the packaging and preparation of food, (20), provided with a dish-shaped container (4), which is provided at the topside with a take out opening, closed by at least two layers of film (8,10) which are placed above each other, whereby at least the bottom film is provided with perforations (18), whereby means are provided to allow for the escape of vapour during use between the bottom film and a film placed above it.

Description

The invention relates to a device for packaging and preparing food. Such a device is out EP 0971649 known.

These known device, in particular for use in a microwave oven is suitable, has a plastic container on the top Side with one with the container welded Foil is closed. The film has a part which, as Valve acts. When heating food in the container a vapor pressure develops in the container through which the pressure in the tank above atmospheric pressure increases. Therefore, the temperature in the container slightly rises above 100 ° C, thereby Food can be prepared very quickly, taking all desired Properties of the food are preserved. The valve will adjusted so that steam at a desired Pressure through the valve can escape, causing excessive temperatures and pressures be prevented.

These Known device offers the advantage of having food easily in this can be packed and transported, keeping the food fresh remains protected against external influences and it also prevents moisture from escaping from the container can. Furthermore, the food can be quickly cooked in this be obtained, for example, aroma, structure, vitamins, etc. stay while too high pressures be prevented. The disadvantage of this device, however in that a relatively expensive valve must be provided.

Further is the attachment of such a valve (a single or multiple Valves per device) complex and time consuming, especially there very carefully must happen. If the fastening is carried out inaccurately, Steam may escape along the valve or may open the valve or loosen the foil, whereupon the device with all associated risks can no longer function properly.

One Another disadvantage of this known device is that the valve can be clogged with food, whereupon no Steam or at least only a limited amount of steam escape can. Another disadvantage is that the device after heating up fairly quickly by the user otherwise the device will be compressed due to pressure differences. When opening consists of the container the danger that the user with the still existing hot steam comes into contact.

In EP 0 661 219 there is described a sheeted film for sealing food containers, the sheeted film having two layers of film bonded together over a large part of the surface and, in use, closing the removal opening of the container prior to closure of the container. Venting channels are provided between the film layers, wherein vent holes are formed in the film edge in the form of tearing valves.

In EP 0 967 160 there is described a substantially similar sheeted film having at least two layers of film bonded together over most of the surface and passing over the removal opening of a container.

It has been proposed to provide a device at the instead of a valve, a sealed with a sticker opening in the Foil is formed.

This The sticker should be removed by the user before heating. The disadvantage of this is that no rapid pressure build-up in the device and the user first manipulates the device before use got to.

Of the Invention is based on the object, a device of the above to create the type described in which occur in known devices Disadvantages are eliminated while the advantages are retained. An inventive device is characterized by the features of claim 1.

A inventive device offers the advantage that the film layers attached in a simple manner can be wherein in use a desired overpressure automatically arise in the packaging and maintained can, for example, a pressure between 1.0 and 4.0 bar and preferably between 1.3 and 1.9 bar, due to the device, the allows the escape of steam.

steam can only escape when a certain higher vapor pressure is reached. Since no valves are required, those described above are Disadvantages eliminated. The slides can be slightly off a roll supplied and be tailored, with also different container sizes easy way considered can be. Furthermore, in this way always a suitable combination of Foils and containers chosen depending, for example, on packaging and preparation Food. Preparation in this context means at least preparing for including the consumption Heat.

at An advantageous embodiment is a device according to the invention characterized by the features of claim 3.

That at least one film, in particular the upper film, gas-tight and liquid-tight accomplished The advantage is that pressure is relatively fast between the lower and said gas-tight and liquid-tight film can build, further including a rapid pressure build up to the desired Level in the container is reached.

at an alternative embodiment are provided several perforated films, in which of the leading away from the lower location Direction the or each over the film disposed on the lower layer has perforations with a total passage area, which is smaller than that of the lower foil.

at A particularly advantageous embodiment is a device according to the invention characterized by the features of claim 5.

at such a device can be located between the two films Escape steam, since the second film at least partially dissolves when the Pressure between the slides exceeds a certain elevated preselected pressure. Such a device is particularly easy to produce, with a automatic action immediately takes place and permissible overpressures easy way by selecting the compounds mentioned adjustable are.

at an alternative embodiment For example, the foil or every other foil is implemented such that when crossing of a certain pressure, to relieve the overpressure to enable.

The Use of a closed gas-tight and liquid-tight film over the perforated lower film in the device according to the invention provides the Advantage that in the closed state prevents moisture through the perforations to the outside outlet, wherein further an air-tight closure can be realized can. This implies that before or during packaging, for example also a modified atmosphere in the container can be created, for example, for preserving packaged Food. The gas in such an atmosphere can only escape if the films separate or at least partially separate each other.

Preferably For example, the perforations in the bottom foil are relatively small and, for example round with a diameter between 50 and 5000 microns, preferably between 100 and 750 μm, or as openings with a different shape but with a similar surface. A Dimension between 200 and 500 μm is particularly suitable. This is a favorable flow resistance for steam achieved, with such perforations relatively accurate to produce are.

at a device according to the invention the lower film is preferably made of a thermally stable laminate, in particular a laminate of polyester and polypropylene. The bottom slide or each over The film arranged on the lower film is thus preferably one Heat-sealing plastic foil, especially polyester, which is removable. It can also vary depending on the application other film materials formed from one or more layers are, chosen be, and the choice is for a professional obviously.

The The invention further relates to a method for producing a device for packaging and food preparation, by the characteristics of claim 14 is characterized.

One such method offers the advantage that a package especially fast and easy to produce, packaged in the food, can be transported and prepared. In such a process can before connecting to the container different superimposed films, for example as a laminate supplied be, wherein the films are also supplied separately can. The slides can for example, fed from a roll and before or during the Positioning can be cut directly. This way you can a very big one Freedom in the design can be achieved, with packaging easy with different sizes can be produced.

The Invention further relates to a process for preparing food, which is characterized by the features of claim 18.

One such method is advantageous in that packaged foods directly into an oven, in particular a microwave oven or steam cooker, can be placed in which the food can be heated and spread quickly, without that its quality is negatively influenced. On the contrary, in the method according to the invention the quality the food on particularly favorable Received manner. In particular, it prevents the packaged Food, for example, dries up or its structure, its Color, its aroma or the like. loses, or at least that these qualities up undesirable Be influenced. Furthermore, in this way the vitamins receive.

In the following claims are de more detailed advantageous embodiments of a device or a method according to the invention shown.

To the better understanding The invention are exemplary embodiments the apparatus and the method according to the invention in the drawing shown. Show it:

1 a schematic exploded perspective view of a packaging device according to the invention;

2 a cross-sectional side view of a 1 shown packaging in the closed state;

3A -C heating food in three successive steps in a package according to the invention;

4 a schematic cross-sectional side view of an alternative embodiment of a package according to the invention;

5 a schematic view of a detail of an edge of a foiled container; and

6 a corner of an alternative embodiment of a packaging device according to the invention.

1 shows schematically an exploded perspective view of a packaging device according to the invention 1 ,

This packaging device 1 has a bowl-shaped container 4 on, which is made for example of hot-melt plastic, as is known in practice and is suitable for use in a magnetron or steam oven. This cupped container 4 has a removal opening on the upper side 2 on, by a flat outwardly protruding edge 6 is surrounded. This packaging device 1 also has a first lower foil 8th and a second top sheet 10 on. Lower means in this context that of the removal opening 2 nearest sheet, upper sheet means the sheet or each sheet on the side of the lower sheet 8th that the removal opening 2 turned away. In the illustrated embodiment, the two films 8th . 10 a surface area that is approximately the upper side of the container 4 corresponds to how they from the longitudinal edge 6 is determined. The slides 8th . 10 are made of a material that is made by heat sealing with the longitudinal edge 6 can be connected. The lower film is preferably made of a thermally stable hot-melt laminate, the upper film 10 is made of a hot glue plastic, preferably a peelable hot glue plastic. 5 shows the slides 8th . 10 over the longitudinal edge 6 , The bottom foil 8th is for example one of a first layer 14 of polypropylene having a thickness, for example, between 60 and 120 μm and in particular 90 μm and a second layer applied thereon 12 made of polyester with a thickness, for example, between 10 and 15 .mu.m, in particular 12 .mu.m, formed laminate. The top sheet 10 is example, made of polyester with a thickness of about 25 microns, preferably made of 20 microns thick peelable hot melt polyester. The materials and dimensions referred to here are given by way of example only and must not be construed as limiting the scope of the invention.

According to 1 shows the bottom foil 8th a pattern of perturbation 16 In the illustrated embodiment, these are a number of perforations 18 with mainly circular cross sections. These perforations have, for example, a diameter between 50 μm and 5000 μm, in particular between 200 and 500 μm, so that drops of water or at least steam can flow through them if there is sufficient pressure in the container 4 is present, as will be explained in more detail.

When used will be a lot of food 20 in the cup-shaped container 4 placed, such as in 2 shown, after which the first lower film 8th by means of first sealing devices 22 around the entire longitudinal edge 6 is fastened around. The first sealing devices 22 are shown here schematically in the form of hatching. It should be noted that any desired suitable sealing method for bonding the first bottom foil 8th with the longitudinal edge 6 or at least with the container 4 can be applied. At the in 2 the embodiment shown is the second film 10 by means of second sealing means 24 with the bottom foil 8th which, in the illustrated embodiment, directly over the first sealing means 22 and the longitudinal edge 6 are arranged. The first sealing devices 22 and the second sealing means 24 are chosen such that the lower film 8th relatively close to the longitudinal edge 6 connected is. These from the first sealers 22 formed compound is stronger than the connection between the lower film 8th and the second film 10 that of the second sealing devices 24 is formed. The purpose for this will be explained later in this document. It should be noted that in the drawing, the thicknesses of the films 8th . 10 the first and two sealing devices 22 . 24 and the cup-shaped container 4 not shown in relation to each other.

If the food 20 such in the packaging device 1 is packed as in 2 shown, it can be transported and stored in the device, the packaging 1 with the food 20 in the closed state in a microwave (magnetron) or steam cooker or the like. can be placed. If the respective oven is switched on afterwards, the food can 20 are prepared using the method according to the invention, as based on 3A -C is explained in more detail. Preparation in this context means at least preparing for consumption, including heating.

3A schematically shows the packaging according to the invention 1 in a relatively cold state. In the interior of the cup-shaped container 4 There is a relatively low temperature T ₀ (for example, room temperature or lower) and a relatively low pressure P ₀ , for example, outside the container 4 prevailing atmospheric pressure P _{A is} comparable. Optionally, a protective gas in the interior of the container 4 be provided to obtain a modified atmosphere. In some cases, this is the food 20 protected by this even better.

When the oven is on, the food becomes 20 heated, taking in the food 20 existing moisture and optionally added moisture is heated and evaporated. This increases the pressure in the container 4 to a relatively high pressure P ₁ , whereby the temperature also rises to a relatively high temperature T ₁ . As a result of the pressure increase, steam will pass through the openings 18 forced, as by the arrows 25 displayed. This steam flows between the lower foil 8th and the top sheet 10 , however, is covered by the second sealing devices 24 prevented from escaping. Thus, the pressure between the lower film increases 8th and the top sheet 10 to a relatively high pressure P ₂ , whereby the temperature also rises slightly to a temperature T ₂ . When the pressure P ₂ exceeds an upper limit, at least a part of the second sealing means breaks 24 on, like in 3C shown, resulting in between the bottom film 8th and the top sheet 10 can flow befindlicher vapor into the environment, so that a pressure equalization takes place at approximately atmospheric pressure P _A. The space in the container 4 under the bottom film 8th expands thereby, wherein a pressure equalization takes place on a pressure P ₃ , which is the maximum pressure, and the temperature rises to a relatively high temperature T ₃ . The temperature T ₃ is for example higher than 100 ° C at the relatively high vapor pressure P ₃ . That means the food 20 is heated relatively quickly, whereby the quality of the food is maintained and the food in particular does not dry out and thus becomes inedible and / or structural, color or taste changes, further for example, the vitamins are retained in a particularly suitable manner. Since the second seal is automatically or at least partially broken when the pressure P ₂ between the film layers 8th . 10 rises, a setpoint is automatically set, for example, the amount of heating, the amount of vapor generated, the internal volume of the container 4 under the bottom film 8th and the total passage area of the passage openings 18 in the lower slide 8th is dependent.

4 shows an alternative embodiment of a device according to the invention 1 in which both the bottom film 8th as well as the upper foil 10 by means of first sealing devices 22 or second sealing devices 24 directly with the longitudinal edge 6 are connected. This has the advantage that a particularly good connection between the second film 10 and the rest of the container 4 is obtained, even if the upper layer of the lower film 8th is not or only insufficiently heat-sealable or else does not allow a suitably trained relatively weak connection.

In a further alternative embodiment, which is in 6 Shown are the top sheet 10 and the bottom foil 8th connected directly to each other, creating the bottom film 8th directly with the longitudinal edge 6 connected is. A line of weakness 26 is in the upper slide 10 trained, which is initially closed. If this packaging 4 with the food 20 placed in an oven and heated, steam flows to the in 3A and B between the first and second foils 8th . 10 , the volume between the films increases and a pressure P ₂ develops. The tear line 26 Tears open when the limit pressure P _{2 is} exceeded, and steam can escape into the environment. In this embodiment, the lower film 8th and the top sheet 10 stay connected to each other and when opening the packaging device 1 demolished and disposed of together.

In the illustrated embodiment, a substantially rectangular container 4 used. However, it is preferable to use a container having, for example, a round or oval shape in which a more uniform heating can be achieved, and moreover a more uniform distribution of heat and vapor pressure can be achieved.

In the present specification, from a cup-shaped container, since this is known in practice. Such a cup-shaped container is produced, for example, by vacuum forming, injection molding or similar techniques, for example of plastic or of plastic-laminated cardboard. In the illustrated embodiments, a container made of a material is used which can be sealed using known sealing methods, in particular heat sealing methods. Such materials used for this purpose are known in the art.

The invention is in no way limited to the embodiments shown in the description and the drawings. Numerous variations are possible within the scope of the invention, which is defined in the claims. Thus, the perforations 16 . 18 be formed in other ways, for example in the form of a regular or irregular matrix of openings 18 , The number and size of the perforations can, depending on the product to be heated, surfaces, contents of the container and the like. be chosen in a simple way. Such a choice is immediately obvious to a person skilled in the art. It is also possible to use more than two films, for example two perforated films arranged one above the other, optionally covered by a closed film, wherein preferably the perforations of the middle film form an overall passage area which is smaller than that of the perforations of the lower film, or at least have a flow resistance which is higher than that of the lower film. In this way, pressure can build up gradually. Further, a container may be used, which is divided into different chambers, wherein at least the lower film is also connected to a partition wall of the various chambers. In particular, the perforations in the lower film may be different for each chamber to achieve different pressures and / or temperatures in these chambers. Any suitable material may be used in a packaging device according to the invention. One or more foils may also be connected to the container in a manner other than by means of the heat-sealing technique, for example using a suitable adhesive technique, welding technology or the like. The top sheet may also be implemented such that it ruptures when a certain or desired maximum pressure is exceeded to allow vapor to escape.

Several perforated film layers are in an alternative non-gas tight Embodiment of Device according to the invention provided, wherein in the direction away from the lower film direction the film or any slide over the former is arranged, has perforations with a total passage area, which is smaller than the lower foil.

These perforations in the above-arranged film are, for example, round and have a diameter between 10 and 1000 μm, preferably between 20 and 100 μm and in particular between 40 and 60 μm. These perforations are formed with a density of, for example, 10 to 1000 perforations per m ² .

The object of this alternative embodiment is to extend the shelf life of the food products packaged in the device, especially those of vegetable materials. Such an arrangement of perforated film layers makes it possible to regulate the O ₂ and CO ₂ levels during transport and storage.

These and numerous comparable variations are considered in scope contemplated by the invention defined in the claims is.

Claims (19)

Contraption ( 1 ) for the packaging and preparation of foodstuffs ( 20 ) with a bowl-shaped container ( 4 ), which is provided at the top with a removal opening which is closed by at least two film layers, which are arranged one above the other, wherein at least the lower film ( 8th ) with perforations ( 18 ), whereby means are provided by which vapor is allowed to penetrate between the lower film during use ( 8th ) and a film arranged above it ( 10 ) escapes, characterized in that the lower film ( 8th ) and the film arranged above it ( 10 ) with each other and / or with the container ( 4 ) by seals ( 22 . 24 ) only at the peripheral edge ( 6 ) of the removal opening ( 2 ) of the container ( 4 ), wherein the at least two foil layers ( 8th . 10 ) substantially over the entire surface area of the removal opening ( 2 ) of the container ( 4 ) are separated so that when, during use, the pressure between the two films ( 8th . 10 ) exceeds an upper limit, at least a part of the seal which connects the upper film to the edge is broken and / or the upper film ( 10 ) is torn, so that the vapor between the films ( 8th . 10 ) escapes. Device according to claim 1, wherein the films ( 8th . 10 ), which consist of at least two layers with a longitudinal edge of the container ( 4 ) are sealed. Apparatus according to claim 1 or 2, wherein at least a film is gas-tight and liquid-tight. Device according to one of the preceding claims, wherein at least one film ( 10 ) above the bottom film ( 8th ), perforations ( 18 ) having a total passage area smaller than the total passage area of the perforations in the lower film ( 8th ). Device according to one of the preceding claims, wherein the lower foil ( 8th ) with the container ( 4 ) and the film or a second film ( 10 ) with the lower foil ( 8th ) is preferably connected along its longitudinal edge, wherein the connection between the lower film ( 8th ) and the container ( 4 ) is stronger than the bond between the lower foil ( 8th ) and the second film ( 10 ) in order to form the means by which an escape of said vapor is made possible, and one and the other are designed such that during a pressure build-up in the container ( 4 ) Gas through the perforations ( 18 ) in the lower foil ( 8th ) and between the lower foil ( 8th ) and the second film ( 10 ) and the connection between the second film ( 10 ) and the lower foil ( 8th ) will at least partially tear off, the connection between the container ( 4 ) and the lower foil ( 8th ) preserved. Device according to one of claims 1-5, wherein the lower foil ( 8th ) with the container ( 4 ) and the film or a second film ( 10 ) with the lower foil ( 8th ) is preferably connected along its longitudinal edge, wherein the connection between the lower film ( 8th ) and the container ( 4 ), the connection between the bottom foil ( 8th ) and the second film ( 10 ) and the film layers are selected such that gas during a pressure build-up in the container ( 4 ) through the perforations ( 18 ) in the lower foil ( 8th ) between the lower foil ( 8th ) and the second form ( 10 ) and the connection between the second film ( 10 ) and the lower foil ( 8th ) at least partially tears off and / or an opening in the second film ( 10 ) is formed in order to form the means by which an escape of the mentioned vapor is made possible for a release of the pressure between the foils, whereby the connection between the container ( 4 ) and the lower foil ( 8th ) remains intact. Device according to one of the preceding claims, wherein the perforations ( 18 ) in the lower foil ( 8th ) have a diameter between 50 microns and 5000 microns, preferably between 100 and 750 microns, in particular between 200 and 500 microns. Device according to one of the preceding claims, wherein the lower foil ( 8th ) is constructed of a thermally stable laminate, in particular a laminate of polyester and polypropylene. Device according to one of the preceding claims, wherein the film or any film ( 8th ), which is attached to the lower, a peelable hot-melt adhesive film, preferably a hot-melt plastic film, in particular a polyester. Device according to one of claims 1-9, wherein a plurality of only perforated foil layers ( 8th . 10 ), wherein at least one film ( 10 ) above the bottom film ( 8th ), perforations ( 18 ) having a total passage area smaller than the total passage area of the perforations in the lower sheet. Device according to one of claims 1-10, wherein a plurality of only perforated foil layers ( 8th . 10 ), wherein at least one film ( 10 ) above the bottom film ( 8th ), perforations having a diameter between 10 and 1000 microns, preferably between 20 and 100 microns and in particular a diameter between 40 and 60 microns contains. Device according to one of claims 1-11, wherein a plurality of only perforated foil layers ( 8th . 10 ), wherein at least one film ( 10 ) above the bottom film ( 8th ), perforations with a density of 10 to 1000 perforations per m ² . Device according to one of claims 1-12, wherein a container is used which is subdivided into different compartments, whereby at least the lower foil ( 8th ) is also attached to a partition wall of the various departments. Method for producing a device for packaging and preparing food, wherein a container ( 4 ) with a food portion ( 20 ), after which the container ( 4 ) mainly by at least two superimposed two films ( 8th . 10 ), which on the container ( 4 ) are sealed, gas-tight and liquid-tight, being used as the lower film ( 8th ) a film ( 8th ) with perforations ( 18 ) is used, through which gas, at least steam from the container ( 4 ), between the films during use ( 8th . 10 ) can flow, in such a way that it comes to a pressure build-up between the films, characterized in that at least two films ( 8th . 10 ) arranged one above the other and on the container ( 4 ) only at the peripheral edge ( 6 ) of the removal opening ( 2 ) of the container ( 4 ), wherein the at least two foil layers ( 8th . 10 ) substantially over the entire surface area of the removal opening ( 2 ) of the container ( 4 ) are spaced apart such that, when in use, the pressure between the two films ( 8th . 10 ) exceeds an upper limit, at least a portion of the seal which joins the upper sheet to the edge breaks and / or tears the top sheet so that the vapor escapes between the foils. A method according to claim 14, wherein as the film or as a second film ( 10 ) at the top of the lower slide ( 8th ) is arranged, a gas-tight and liquid-tight film is used. A method according to claim 14 or 15, wherein the film layers ( 8th . 10 ) on the container ( 4 ) and / or attached to each other, in particular sealed, wherein the lower film ( 8th ) with the container ( 4 ) that this connection is stronger than the connection between the film or any film ( 10 ) and the lower foil ( 8th ) and / or the container ( 4 ), and one and the other are formed such that the second film ( 10 ) in use due to pressure build-up between the foils ( 8th . 10 ) dissolves or at least partially dissolves, without the lower film ( 8th ) releases from the container. A method of manufacturing a device for packaging and preparing food according to any one of claims 14-16, wherein a container ( 4 ), which is subdivided into different compartments, whereby at least the lower foil ( 8th ) is also attached to a partition wall of the various departments. Process for preparing food, whereby the food is placed in a container ( 4 ), the container with at least one perforated bottom film ( 8th ) and a second, on top of her slide ( 10 ), the lower film ( 8th ) and the second film ( 10 ) on the container only at the peripheral edge ( 6 ) of the removal opening ( 2 ) of the container ( 4 ), wherein the at least two foil layers ( 8th . 10 ) substantially over the entire surface area of the removal opening ( 2 ) of the container ( 4 ), after which the container ( 4 ) is placed in a closed state in a stove, preferably a microwave oven or a steam oven, after which the food is heated so that in the container steam is evolved, wherein the steam flows at least partially between the perforated film and the second film and causes a higher pressure between the films, wherein the second film at least partially dissolves and / or tears near the peripheral edge, so that the built-up pressure is released while the lower film remains attached to the container and the pressure in the container at least slightly is kept above the atmospheric pressure. Process for the preparation of food, whereby the food is placed in a container ( 4 ) according to claim 18 and a container ( 4 ), which is subdivided into different compartments, whereby at least the lower foil ( 8th ) is also attached to a partition wall of the various departments.