GB2368331A

GB2368331A - Heatable packaging for a food product

Info

Publication number: GB2368331A
Application number: GB0125847A
Authority: GB
Inventors: Martin Daniels
Original assignee: W K Thomas & Co Ltd
Current assignee: W K Thomas & Co Ltd
Priority date: 2000-10-28
Filing date: 2001-10-29
Publication date: 2002-05-01
Anticipated expiration: 2021-10-29
Also published as: GB0026401D0; GB2368331B; GB0125847D0

Abstract

Heatable packaging for a food product comprises an outer packaging layer 14 and an inner packaging layer 15 with a space therebetween. The space contains a liquid or solid 17 which when heated is vapourised, with the inner packaging layer 15 being arranged to allow the vapour produced to pass through and thus heat the food products 10,11,12. The inner and outer packaging layers 14,15 are preferably formed by a double-skinned foil and both are preferably thermally conductive, the inner packaging layer 15 may also be perforated. The liquid 17 contained in the space is preferably at least partly stock. The packaging is preferably sealed by a semi-permeable sealing layer 18 or a clip- on, non-sealed lid.

Description

PACKAGING FOR FOOD PRODUCT This invention relates to packaging for food products and also to a food product so packaged. The invention has particular application to packaged meals which are served on-board by airlines.

When pre-cooked, pre-packaged airline meals are re-heated prior to serving, the re-heating is normally carried out in an electric oven. In this case the heat often tends to'dry out'the food product as it is transmitted directly from the (heated) packaging to the food. In places where the food directly contacts the hot packaging it often burns. Another disadvantage of such re-heating is that due to the break down in starches contained in sauces forming part of the food product meal, due to the heat, such sauces fail to keep moist the protein of the meal by not adhering thereto.

An object of the invention is to overcome or at least minimise at least some of the disadvantages mentioned above.

According to the present invention there is provided packaging for a food product, the packaging comprising an outer packaging layer and an inner packaging layer defining a space therebetween, and liquid or solid being freely provided in said space, the inner packaging layer being arranged to allow said liquid or solid in vaporised form to pass therethrough, in use, to heat said food product.

Preferably there is liquid between the inner and outer packaging layers, and conveniently said liquid is at least partly water, for example stock. Desirably the liquid is between a double-skinned foil which constitutes said outer and inner packaging layers. Said inner, second skin is advantageously perforated to allow passage of steam (vaporised stock) therethrough when the trapped liquid is heated, by the application of heat to the packaging, in use. The outer, first skin is conveniently thermally conducting.

The invention also relates to a packaged meal in the form of a food product packaged in said packaging. Advantageously a sealing layer is applied over the food product to seal it in the packaging. Preferably said sealing layer is a semi-permeable film which is sealed to one or both of the outer and inner packaging layers. Alternatively instead of a sealing layer, a (punctured) clipon lid may be provided.

The packaged meal preferably includes at least one sauce which adheres to a protein containing portion of the food product during the re-heating of the packaged meal, in use, so that said portion cooks (is re-heated) therein. The sauce contains unique active starches which prevent the sauce breaking down under said re-heating and thus not adhering to said portion of the meal.

The invention will now be described, by way of example, with reference to the accompanying drawing, the single figure of which is a schematic, interior side view of a food product packaged in packaging of the invention.

In the drawing, there is shown a packaged ready-to-heat meal in which three different types of food product 10,11 and 12 respectively are sealed in packaging denoted generally at 13.

The packaging is in the general form of a tray, which is preferably oval, with, in the embodiment illustrated, an upwardly, outwardly sloping side.

The packaging tray is formed by a double-skinned foil construction. Whilst it is not essential that the same material is used for both skins, it is important that the outer skin 14 is a good thermal conductor, as will be described hereinafter, and it is preferred that the inner skin is also a thermal conductor.

Preferably the material used is a metal foil, e. g. aluminium.

As seen in the drawing, an inner skin 15 of the double-skinned tray construction is spaced from the outer skin, the two skins being joined together solely at the upper peripheral edge of the tray, where, as shown, the two skins can be formed together as a lip 16.

Freely provided in the space formed between the inner and outer skins is water 17, preferably in the form of food stock or the like. At least the base part of the inner skin 15, but not of the outer skin 14, is perforated, as shown, so that, as will be explained, when the meal is heated or re-heated, steam/vaporised stock can pass through the perforations in the skin 15 to heat the food products 10,11 and 12.

During production of the packaged meal, the water/stock is freely provided in the space between the inner and outer skins, and once the required food product has been placed within the tray, this is preferably sealed by a semipermeable lid or cover 18 across the open top of the tray, with the respective edges of the film being sealed at the respective lips 16 around the top edges of the tray. The cover 18 could be in the form of a film or a foil. In one arrangement the cover 18 is a foil which has a number of spaced peripheral portions turned down over the lip 16 to secure the cover 18 in place.

Moreover the foil has a number of slits or other openings therein to provide said semi-permeability. Alternatively, instead of a sealing cover, a clip-on lid, preferably punctured, is provided. This could be of aluminium. Sealing is not required in this case as the packaged meal would be kept frozen before use.

Accordingly, when the packaged meal shown in the drawing is placed in a steam oven, or otherwise heated, other than in a microwave oven, for which the packaged meal is not intended, the heat will be conducted by the outer skin 14 to the liquid in the space between the inner and outer skins. As a result of this heating, the liquid will vaporise and the vaporised water/stock will pass through the perforations in the inner skin 15 into the interior of the tray where the food products 10,11 and 12 are disposed, thereby gently heating same. By the use of steam/vaporised stock there is created an 'atmosphere'within the tray which prevents the food products from drying out in the fierce heat of the (non-microwave) oven. With presently known 'ready meals'where no such'atmosphere'is provided around the food product being re-heated, the food products often dry out in the (nonmicrowave) oven, and burning of the product can occur where it contacts the directly heated hot container. The double-skinned foil arrangement of the tray described protects the food products from such damaging heating.

It will be appreciated that any suitable liquid can be utilised to provide the gentle'atmosphere'around the food product as it is being heated or re heated, and it may in fact be possible to use instead a solid rather than a liquid, a solid, when heated, passing either directly to a vapour, or passing through the intermediate stage of a liquid. A combination of liquid and solid may also be possible. The semi-permeable nature of the film which seals the product in the tray, and the alternative punctured clip-on lid, are each advantageous in allowing the vapour to escape, thereby ensuring that it flows freely through the whole of the interior of the tray thereby fully re-heating all of the food products. However in other embodiments, other forms of sealing film or lid could be used and these may not be permeable. One alternative may be that when the product has been heated or re-heated sufficiently, the seal is destroyed by the film separating from the tray thereby to allow escape of the hot vapour immediately before the package is removed from the oven.

One or more sauces is provided as part of the packaged meal, i. e. on at least one of the food products, it being intended that this mixes with protein of the food product (s) of the meal so that as the cooking/re-heating proceeds the protein containing food product is'cooked', i. e. (re-heated), in the sauce.

The or each sauce contains at least one unique active starch which ensures or ensure that each sauce adheres to the protein containing food product during the re-heating, in contrast to known arrangements where the sauce breaks down, such that, in the present arrangement, such a known sauce could run down through the perforations in the inner skin 15. It is preferred that the packaged meal of the invention incorporates such a sauce or sauces, so as to ensure product quality and that the functionality of the package totally delivers. The starches of the sauces hold water of the sauces until cooking begins, and then release it at the correct rate as the temperature rises.

The present application relates both to the packaging tray itself and also to a packaged meal incorporating a food product within the tray together with the sealing film in place. Such a packaged meal is particularly suitable for catering on airlines.

Claims

CLAIMS 1. Packaging for a food product, the packaging comprising an outer packaging layer and an inner packaging layer defining a space therebetween, and liquid or solid being freely provided in said space, the inner packaging layer being arranged to allow said liquid or solid in vaporised form to pass therethrough, in use, to heat the food product.
2. Packaging as claimed in Claim 1, wherein the inner and outer packaging layers are defined by a double-skinned foil.
3. Packaging as claimed in Claim 1 or Claim 2, wherein said inner packaging layer is perforated to allow said vaporised liquid or solid to pass therethrough, in use.
4. Packaging as claimed in any one of Claims 1 to 3, wherein the outer packaging layer is thermally conductive.
5. Packaging as claimed in any one of Claims 1 to 4, wherein the inner packaging layer is thermally conductive.
6. Packaging as claimed in Claim 2, in the form of a tray defined by the two skins of said double-skinned foil, which are joined together solely at an upper peripheral edge of said tray.
7. Packaging as claimed in Claim 6, wherein the joining together of the two skins defines a lip.
8. Packaging as claimed in any of the preceding claims, wherein liquid is freely provided in said space.
9. Packaging as claimed in Claim 8, wherein said liquid is at least partly stock.
10. A packaged meal comprising an outer packaging layer and an inner packaging layer defining a space therebetween, liquid or solid being freely provided in said space, the inner packaging layer being arranged to allow said liquid or solid in vaporised form to pass therethrough, in use, and a food product in the interior of the inner packaging layer, such that, in use, said vaporised liquid or solid passing through the inner packaging layer heats the food product.
11. A packaged meal as claimed in Claim 10, comprising on said food product at least one sauce containing at least one starch which during said heating of the food product, in use, adheres to protein thereof.
12. A packaged meal as claimed in Claim 11, wherein the or each sauce contains water which is released therefrom, in use, as heating of the food product proceeds.
13. A packaged meal as claimed in any one of Claims 10 to 12, comprising a sealing layer to seal the food product in the interior of said inner packaging layer.
14. A packaged meal as claimed in Claim 13, wherein the sealing layer is semi-permeable to allow said vaporised liquid or solid to escape, in use, from said interior of the inner packaging layer.
15. A packaged meal as claimed in any one of Claims 10 to 12, comprising a clip-on, non-sealed lid.
16. Packaging for a food product substantially as hereinbefore described, with reference to, and as shown in the accompanying drawing.
17. A packaged meal substantially as hereinbefore described, with reference to, and as shown in the accompanying drawing.