EP0284137B1

EP0284137B1 - Package

Info

Publication number: EP0284137B1
Application number: EP19880200454
Authority: EP
Inventors: Pieter Jacobus Rienks; Jan Van Der Veen
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 1987-03-17
Filing date: 1988-03-09
Publication date: 1992-08-12
Anticipated expiration: 2008-03-09
Also published as: ATE79354T1; GR3006201T3; EP0284137A1; DE3873571D1; ES2035238T3; DE3873571T2

Abstract

Package comprising a container (1), at least partly open at its upper side, on which an edible material (4) is placed that extends above the container, and a cover (5) which is attached to and seals the container, characterized in that the cover is made mainly of a not self-sustaining material, and the dimensions of the cover are such that it can be released therefrom without deforming the edible material, while the attachment of the cover to the container remains intact. Preferably, a plate is used as container.

Description

The invention relates to a package comprising a container, at least partly open at its upper side, on which is placed an edible material that extends partly above the container, and a cover attached to and sealing the container.
For packaging edible materials, use is often made of a container and a cover fitting on it.
One of these already known packages is concerned with a container on which an edible material has been placed that extends partly above the container, the container being sealed with a rigid lid formed such that it does not come into contact with the edible material. However, in comparison with the use of a not self-sustaining cover, the use of such a lid entails a considerable increase in costs.
A second already known package comprises a container on which an edible material is placed which, however, does not extend above the container, and a not self-sustaining cover for the container. Such packages have the disadvantage that, particularly when a shallow dish or a plate is used as container, the choice of edible materials that can be packaged is limited. Common edible materials such as potatoes, meat and poultry are often too large to be packaged in such a package.
A third already known package comprises a container on which an edible material is placed extending above the container and a not self-sustaining cover for the container which is tightly stretched over the edible material. This package has the disadvantage that the material packaged therein is often deformed during packaging. Upon heating of materials in the package, the covering material often adheres to the edible material. This can lead to local burning and can also adversely affect the appearance of the product. Such packages are, for instance, described in US H 896,016 and US 3,245,338.
The invention aims at overcoming the above-mentioned disadvantages; in particular the invention aims at providing a package comprising a not self-sustaining cover, in which vapour is developed during heating, so that, as a result thereof, the pressure inside the package increases somewhat, causing the cover to be released from the edible material.
It has now been found that the above-mentioned disadvantages can be avoided by using a package according to the invention which comprises a container, at least partly open at its upper side, on which is placed an edible material that extends above the container, and a cover which is attached to and seals to the container, which cover is made at least mainly of a not self-sustaining material, characterized in that the surface of the cover situated within the seal to the container is larger than the surface of an imaginary foil stretched tightly from the said seal over the container and the edible material, so that above the edible material, the cover is spaced from the edible material or is draped in a slack condition over the edible material, whereby there is space between at least some of the edible material and the overlying cover, and the cover can be released from any contact with the edible material while the attachment of the cover to the container remains intact.
A process according to the invention is defined in the independent claim 9.
In this way, either the cover does not come into contact with the edible material, or it is lying only loosely on the product to be packaged, so that the contact between the cover and the edible material can be broken without deformation of the edible material or damage to the package occurring. Releasing the cover from the edible material can, for instance, take place during warming up, the cover being released from the product because of the formation of vapour.
The surface of the cover situated within the sealing edge is larger than the surface of an imaginary foil stretched tightly from the sealing edge over the container and the edible material. Here, by sealing edge is understood the boundary by which the interior of the package is separated from the rest of the surrounding area. By the tightly stretched, imaginary foil is understood a very flexible foil which, without folds, is stretched tightly over the container and its contents without deformations of the contents occurring.
Preferably, care is also taken here that, in those parts of the cover that are situated above the edible material extending above the cover, no stresses are set up.
For this, it is preferred that the dimensions of the cover are chosen such that the cover does not leave too much space open between the edible material and the cover. As a result thereof, dehydration of the edible material during storage and warming up is avoided, while movement of the edible material is also reduced to a minimum. Preferably, the dimensions of the cover are chosen such that the ratio between the surface of the cover situated within the sealing edge and the surface of an imaginary foil tightly stretched from the sealing edge is smaller than 1.5:1, more preferably smaller than 1.2:1. With such dimensions, the cover is often large enough for no deformation of, or damage to, the edible material to be caused, while also there is not too much play between cover and edible material, as a result of which dehydration and mixing of different components of the edible material can be prevented to a large extent. The amount of covering material can also be reduced by this.
As container, various containers commonly employed in food industry can be used, such as pans, boxes, dishes, glass pots etc. If the package is intended to be heated before the edible material is consumed, the container and the cover will be manufactured from a material that is resistant to heat and/or microwave radiation. The use of polyethylene terephthalate (PET) is particularly advantageous as packaging material.
The upper side of the container should at least be partly open. Here, by upper side of the container is understood that side which, during normal use of the container when the edible material is placed on it, is at the top. Naturally, after sealing of the container with the aid of a cover, the container can possibly change position. If, however, a direction or an orientation is indicated in this application, reference is made here to the prevailing orientation of the package during the positioning of the edible material.
A particularly advantageous embodiment of a package according to the invention comprises a plate as container. By plate is understood here an object provided with a substantially flat bottom and a somewhat raised edge part, which is used for consuming meals from. This term encompasses, inter alia, flat, deep, round, square and compartmented plates. The use of a plate as container in a package according to the invention has the advantage that, after removal of the cover, the meal is ready for consumption in an attractive form.
Preferably, the container is provided with an edge to which the cover can be attached. Preferably, here a container is used having an at least partly flat edge, by which is understood an edge which is provided with a completely, or substantially completely, horizontal edge part close to the whole circumferential edge of the container. Such an at least partly flat edge has the advantage that the cover can be attached in a simple manner to the flat part. Particularly suitable is the use of a container, the edge part of which is provided with a flat, embossed edge. Here, by a flat, embossed edge is understood a continuous, flat, strip-shaped, raised or lowered face situated close to the circumferential edge of the container. The cover can be attached to this flat, embossed edge in a simple manner, the attachment also being such that, optionally after heating, the cover can be removed without auxiliary means. Such a detachable attachment is very handy in practice.
Particularly useful is a package according to the invention which comprises frozen, edible material, for instance a deep-frozen meal. Such meals will often be placed on the container in non-frozen state. In this non-frozen state, the components of the meal are relatively vulnerable. After sealing of the container with the aid of the cover, the meal is frozen, as a result of which the vulnerability decreases somewhat. In this manner, it is possible to prevent the edible material from being damaged after packaging by external influences, for instance during transport and storage.
Other uses of a package according to the invention relate, for instance, to the packaging of meals which are placed on the container in cooled form and are thereafter stored under chilled conditions. It is also possible to put edible materials in frozen state on the container, whereafter the package is stored in frozen state.
Preferably, the cover is manufactured from a not self-sustaining foil material, such as aluminium foil, plastic foil, PET foil and the like. If the package is intended to be heated, it is preferred that a heat-resistant foil be used. Such materials are cheap and easy to handle. Use of an at least partly transparent foil has the further advantage that the edible material can be seen by the consumer without the package having to be opened. This also has the advantage that such a packaging material readily allows the passage of heat radiation, as a result of which the heating time can remain limited. Particularly advantageous is a package according to the invention in which the cover is attached to the edge or the flat part of the edge of the container. With this the amount of material used in the cover is reduced to a minimum. In order to increase the self life of the edible material in the package and to avoid entry of ambient soil, it is preferred that the cover be attached to the container in such a manner that the interior of the package is sealed. Such sealing can, for instance, be achieved by gluing the cover to the container. Particularly advantageous is the attachment of the cover to the container by means of heat-sealing. The attachment of the cover to the container is preferably detachable so that, possibly after heating, the cover can be removed without using any auxiliary means.
As cover, for example, a thermally pre-formed covering material can be used, and it is also possible to bring the covering material into the desired form by pleating. Preferably, a flat piece of foil is used as material for the covering, which is attached in pleated form to the container. This embodiment has the great advantage that the starting material is cheap and no expensive equipment is necessary for giving the covering material the desired form before it is placed on the container. Preferably, before being attached to the container, the cover is pre-formed by pleating a flat piece of foil into dome-shape.
The attachment to the container in pleated form will, in principle, adequately seal the container, so that entry of contamination from the environment is prevented. During possible warming up, the cover will be released from the product because of vapour formation. Preferably, the pleated cover is attached to the container such that fine channels are formed between container and cover. An advantage of this is that, during warming up, any excess vapour can escape through these fine channels without the attachment of the foil to the container being broken.
The invention is further illustrated by the figures, in which

Fig. 1A: shows a cross-section of a preferred embodiment of a package according to the invention;
Fig. 1B: shows, for comparison, the container of Fig. 1A provided with a foil tightly stretched from the sealing edge;
Fig. 2A: shows a cross-section of a second embodiment of a package according to the invention, and
Fig. 2B: shows, for comparison, the container of Fig. 2A provided with a foil tightly stretched from the sealing edge.

Fig. 1A gives a cross-section of a preferred embodiment of a package according to the invention comprising a round plate 1, provided with a raised edge part 2 and a flat edge 3, which is provided with an embossed edge 7, which is, for instance, 4 mm wide and 1 mm high. An edible material is placed on the plate in the form of a frozen meal 4, the meal partly extending above the plate. The plate is sealed by a piece of foil 5, which is detachably attached in pleated form (not visible) to the embossed edge 7 by means of heat sealing, as a result of which a sealing edge 6 is formed.
The dimensions of the covering foil are such that it can be released from the meal without deforming said meal, while the attachment of the covering foil to the container remains intact. This release takes place automatically during warming up, during which the cover is released from the product by vapour formation.
Fig. 1B shows a cross-section of the plate of Fig. 1A. The board is sealed by a foil 8b, which is stretched tightly from the sealing edge 6b over the plate and the meal placed thereon. The ratio between the surface of the covering foil 5 situated within the sealing edge in Fig. 1A and the surface of the tightly stretched foil situated within this edge in Fig. 1B is 1.1:1.
Fig. 2 shows a cross-section of a second embodiment of a package according to the invention comprising a round plate 11, provided with a raised edge part 12 and a flat edge 13. An edible material is placed on the plate in the form of a meal 14, the meal extending partly above the plate. The plate is sealed by a round piece of foil 15, which is attached in pleated form (not visible) by means of gluing to the lower part of the edge, as a result of which a sealing edge 16 and a gluing edge 17 are formed. The dimensions of the piece of foil are such that it can be released therefrom without deforming the meal, while the attachment of the foil to the plate remains intact.
Fig. 2B shows, for comparison, a cross-section of the plate of Fig. 2A, comprising a round plate 11b, on which a meal 14b placed. The plate is sealed by a foil 18b, which is tightly stretched from the sealing edge 16b over the plate and the meal placed thereon. The ratio between the surface of the covering foil situated within the sealing edge in Fig. 2A and the surface of the tightly stretched foil situated within this sealing edge in Fig. 2B is 1.14:1.

Claims

A package comprising a container (1,11), at least partly open at its upper side, on which is placed an edible material (4,14) that extends above the container, and a cover (5,15) which is attached to and seals to the container, which cover is made at least mainly of a not self-sustaining material, characterized in that the surface of the cover situated within the seal (6,16) to the container is larger than the surface of an imaginary foil stretched tightly from the said seal over the container and the edible material, so that above the edible material, the cover is spaced from the edible material or is draped in a slack condition over the edible material, whereby there is space between at least some of the edible material and the overlying cover, and the cover can be released from any contact with the edible material while the attachment of the cover to the container remains intact.
Package according to claim 1 wherein the surface area of the cover situated within the said seal (6,16) does not exceed 1.5 times the surface area of a said imaginary foil stretched tightly from the said seal.
Package according to claim 1 or claim 2 wherein the container is a plate.
Package according to any one of claims 1 to 3 wherein the edible material is frozen or chilled.
Package according to any one of claims 1 to 4 wherein the cover is made of a flat piece of sheet material which is attached to the container in pleated form.
Package according to claim 5 wherein the pleated cover is attached to the container such that fine channels are formed between the container and the cover.
Package according to any one of claims 1 to 6 wherein the cover is attached to the container by heat-sealing.
Package according to any one of claims 1 to 7 wherein the container and the cover are made of heat-resistant and/or microwave-resistant material.
Process for packaging an edible material, in which an edible material (4,14) is placed on a container (1,11) which is at least partly open at its upper side, the edible material extending partly above the container, whereafter the container is sealed by the attachment of a cover (5,15) to the container, which cover is made at least mainly of a not self-sustaining material, characterized in that the surface of the cover situated within the seal (6,16) to the container is larger than the surface of an imaginary foil stretched tightly from the said seal over the container and the edible material, so that, above the edible material, the cover is spaced from the edible material or is draped in a slack condition over the edible material, whereby there is space between at least some of the edible material and the overlying cover, and the cover can be released from any contact with the edible material while the attachment of the cover to the container remains intact.
Process according to claim 9 wherein the cover, before it is attached to the container, is pre-formed by pleating a flat piece of sheet material into dome-shape.
Process according to claim 9 or claim 10 wherein the edible material is placed on the container in a non-frozen state and the edible material is frozen after packaging.
Process according to claim 9 or claim 10 wherein an at least partly frozen, edible material is placed on the container, in an at least partly frozen state.