EP1231160A1 - Package for the preservation and cooking or reheating of food products - Google Patents

Abstract

Package consists of a tray with an impermeable base (11) and a false bottom (1) with perforations (2), covering a humidifying or moisturizing pad (15) soaked in water and an optional treatment product. The tray is sealed with a thermoplastic film layer. The perforations are distributed evenly over the whole surface of (1), each lying in the center of a depression (6) made on both sides of it.

Description

The present invention relates to a packaging for preservation and / or cooking or reheating food.

In particular, the present invention relates to packaging for the preservation and / or cooking or reheating food products that require moist conditions either for their conservation and / or possibly for their cooking or reheating.

Many food products such as some fresh or pre-cooked vegetables, fresh meat or seafood products, or certain cooked dishes, are sold in a tray of suitable plastic material on which the food product is housed, the whole being wrapped in a thermoplastic film, welded to the tray which gives airtight packaging. In some cases the packaging also contains instructions for cooking or reheating the product.

It has recently been found that in the case where the product to be preserved is a fresh product, its better conservation to avoid the risk of accelerated dehydration is found when the product is maintained under desirable hygrometry conditions and only in the event that the product is a product to be cooked or reheated by passing the packaging through a microwave, it is very advantageous to cook it or reheat it with saturated steam because in this case the consistency and organoleptic qualities of the product as well as the vitamins which are contained are not altered.

For example we already know on the market packaging called Concept Hydrapack ™ and Concept Thermipack ™, which are based on this idea. In these food products are housed in a hermetically sealed package enclosed comprising a tray with an impermeable bottom and a false bottom provided with perforations, placed above and away from the bottom, a saturator or humidifier pad soaked with water, with or without the addition of a treatment agent, being placed between said bottom and said false bottom, the tray being closed by a thermoplastic film welded on the edge of the tray or welded on itself generally below the tray in a way hermetic.

In the case of packaging of products to be cooked or reheated, the packaging, either the tray as well as the saturator pad and the external film are produced with thermoplastic materials which are transparent to microwaves and heat resistant given off by microwave ovens when in use.

Today the tray used in these applications is a tray with a bottom waterproof and a false bottom arranged above and at a distance from the bottom, where the false bottom presents perforations which have been studied and perfected to allow the flow and the concentration of exudates in the bottom of the tray itself. Examples of trays commonly used in these new applications are those described for example in European patent applications published under the numbers EP-A-701,995 and EP-A-732,275.

We have now found that much more favorable results can be obtained if the false bottom is perforated in a special way because we can thus obtain a better distribution of the steam which emerges from the saturator buffer in the packaging, in especially when the packaging is going to go in the microwave.

In particular, we have found that when using packaging as described more high, we can obtain a very good distribution of the vapor which emerges from the buffer saturator, if a perforated false bottom is used where the perforations are distributed regularly on its surface and cover the entire surface, and each of them is at the center of a depression created symmetrically on the two surfaces (towards the product and towards the bottom of the tray and the tampon), this depression having the shape of a small bowl, round or even oblong, flattened.

• la figure 1 représente une vue de dessus d'un faux-fond selon la presente invention;
• la figure 2 représente une vue en coupe transversale, suivant l'axe de coupe AA de la figure 1, du faux-fond;
• la figure 3 représente une vue en coupe transversale d'une barquette dans laquelle un faux-fond selon l'invention doit être logé; et
• la figure 4 représente une vue en coupe transversale d'une barquette contenant le faux-fond selon la presente invention.

The invention will be better understood on reading the description which follows, referring to the appended drawings relating to nonlimiting examples but only explanatory embodiments where

• Figure 1 shows a top view of a false bottom according to the present invention;
• 2 shows a cross-sectional view, along the cutting axis AA of Figure 1, of the false bottom;
• Figure 3 shows a cross-sectional view of a tray in which a false bottom according to the invention must be housed; and
• Figure 4 shows a cross-sectional view of a tray containing the false bottom according to the present invention.

Figure 1 illustrates a top view of an embodiment of a false bottom according the invention.

The shape and dimensions of the false bottom 1 are dictated by the shape and the dimensions of the tray in which the false bottom is to be housed. Figure 3 illustrates a conventional tray 10. In general the tray 10 has a rectangular shape with the rounded corners, this tray having a bottom 11 and a side wall 12 surrounding the bottom 11. The side wall 12 is generally inclined towards the bottom 11 of the tray, as in the Figure 3, but it can also be perpendicular to the bottom 11. The side wall 12 of the tray is generally surmounted by a collar 13 whose free surface is coplanar with bottom of the tray. This collar is in particular used in certain cases to weld it the thermoplastic film used as a sealing film. The dimensions of trays are standard dimensions such as 14 cm x 23 cm, 16 cm x 25 cm, etc. The dimensions of the tray used as false bottom will therefore be chosen so that position the perforated tray in the tray at the distance from the bottom chosen.

The false bottom has a multiplicity of perforations 2 distributed regularly over its surface which preferably cover the entire surface.

In one embodiment, these perforations are aligned so as to form rows 4 parallel to each other and parallel to the lateral edges of the tray 1. The perforations 2 are distributed over rows 4, 4 ', 4 ", etc. so that they substantially form regular grids of rows 4, 4 ', 4 "and columns 5, 5', 5", etc. on the surface of the false bottom 1, as seen more precisely in FIG. 1. The present invention is not limited to this method of distributing the perforations 2.

In a variant, the consecutive rows 4, 4 ′, 4 "of perforations 2 are offset two in pairs so that the set of perforations 2 has repeated patterns of staggered. In another variant, the rows are offset three to three.

The dimensions and frequency of distribution of the perforations are desirably chosen according to the product to be packaged as well as the dimensions of the packaging.

In general the average diameter of the perforations is between 0.3 and 5 mm, advantageously between 0.5 and 4 mm, more advantageously between 0.8 and 3 mm, and even more advantageously between 1 and 2.5 mm.

Each perforation 2 is at the center of a depression 6 created symmetrically on each surface of the false bottom, this depression having the shape of a small bowl, of preferably round, flat.

As appears better in Figure 2, these cavities are formed both on the surface from the tray on which the product is placed and on the surface to the saturator pad. These cavities have an average diameter 7 which is at least three times, typically between 3 and 15 times the average diameter of the perforations and preferably between 5 and 15 times for the perforations smaller (0.3-2 mm) and between 3 and 6 for larger perforations (2-5 mm).

For example for perforations having an average diameter of 1 mm, the cavities can have an average diameter of at least 3 mm, such as for example 5 mm, 8 mm, 10 mm, or 12 mm, when for perforations having an average diameter of 2.5 mm, the cavities can have an average diameter of at least 7.5 mm, such as for example 8 mm, 10 mm, 12 mm, or 15 mm.

The distance 8 between two consecutive perforations is greater by half the sum of the cavity diameters.

In general the distance between two consecutive perforations is chosen so that there at least 1 mm, preferably at least 2 mm on the surface of the false bottom, between the edges respective cavities.

For a better distribution of the vapor in general the distance 9 between the edges of the two consecutive cavities is not more than 1 cm, preferably not more than 8 mm, more preferably not more than 5 mm, and even more preferably not greater than 3 mm.

The edges of the cavities are preferably rounded.

In another embodiment the cavities are oblong with the main axes aligned. In this case, the same considerations we made above regarding their dimension, can be applied where as the mean diameter is meant the half-sum of main axes.

The false bottom is generally made of the same plastic material that is used for the tray. In general it is an expanded plastic material such as polystyrene, polypropylene or polyester. For applications where we pass the packaging in the microwave we must use plastics, such as polypropylene or polyester, which resist the heat given off by microwave ovens, practically at a heat at least equal to 100 ° C, causing no deformation or migration of their components to food.

The thickness of the plate used for the false bottom is generally between 1 and 10 mm, preferably between 2 and 8 mm, and even more preferably between 3 and 7 mm.

The perforations as well as the cavities are easily created by compression using punches of appropriate shape and size.

The punching operation is generally carried out on the false bottom plate before its placement in the tray or it can be performed on a surface of the front tray and on the other surface, that which is in contact with the food product, after its installation.

The false bottom can be adapted to the tray by any process ensuring the tightness of the connection: welding, clipping and the like. For example the tray can contain two edges interiors 14 which extend along the side wall 12 parallel to the long sides of the tray and which have a substantially coplanar free surface at the bottom of the tray and the false bottom will be welded or glued to these edges. This embodiment is illustrated in the Figure 4 which shows a cross-sectional view of a tray 10, with the edges interiors 14, on which the false bottom 1 according to the present invention is welded or glued. In this figure, the saturator pad positioned between the bottom 11 of the tray and the false bottom 1, is indicated in 15.

In another embodiment, the tray contains tips at the four corners where the false bottom, which in turn contains holes in corresponding positions, will be clipped.

Preferably the false bottom and the tray can be linked by clipping. In this case the making the food product is more pleasant and requires no tools particular. The saturator pad, previously and desirably soaked for example water, wine, lemon juice, vanilla extract, etc., may be present on the bottom of the tray before installing the false bottom, just before packaging the product. Other an appropriately sized hole should be provided in a corner of the false bottom attached to the tray containing a non-soaked pad, for the flow of the chosen liquid before the conditioning.

When the product to be packaged has been placed on the false bottom of the tray containing the pad wettably soaked, the tray is closed with a thermoplastic film which can be welded or glued to the tray flange as a sealing film or can completely wrap the tray and be welded or glued on itself forming a pocket containing the tray. Preferably, the thermoplastic film is a film heat-shrinkable and the packaging is finally subjected to a heat treatment which causes the shrinkage of the film. The thermoplastic film used in packaging according to the present invention can be a single-layer or multi-layer film and can be made of any plastic material having the qualities required for the realization of the packaging and, if necessary, for passage into the oven.

• soit une perforation dans la pellicule thermoplastique, cette perforation étant obturée par une étiquette operculée détachable par 1e consommateur au moment du passage au four,
• soit une valve dans la pellicule même qui permet l'échappement de la vapeur uniquement quand on dépasse une valeur de pression prédéfinie;
• soit encore une faiblesse de la soudure entre la pellicule d'operculage et la collerette de la barquette dans une certaine zone de cette soudure de manière que dans cette zone elle ne supporte pas la pression de la vapeur saturante au-dessus d'une certaine valeur.

When the packaging according to the present invention is carried out with a view to cooking or reheating the food product which it contains, in order to avoid any undesirable deformation of the container by overpressure, provision may be made

• either a perforation in the thermoplastic film, this perforation being closed by a sealed label detachable by the consumer at the time of passage in the oven,
• either a valve in the film itself which allows the steam to escape only when a predefined pressure value is exceeded;
• again a weakness of the weld between the sealing film and the collar of the tray in a certain zone of this weld so that in this zone it does not withstand the pressure of the saturated vapor above a certain value .

It goes without saying that many variations can be made, in particular by substitution equivalent technical means, without departing from the scope of the invention.

Claims (12)

A package for the preservation and / or cooking or reheating of food products in which the food products are housed in a tray comprising an impermeable bottom and a false bottom provided with perforations, placed above and at a distance from the bottom, a saturator or humidifier pad soaked in water, with or without the addition of a treatment agent, being placed between said bottom and said false bottom, the tray being closed by a thermoplastic film welded or glued to the edge of the tray or welded or stuck on itself in a hermetic manner, this packaging being characterized in that the perforations of the false bottom are distributed regularly over its surface and preferably cover the entire surface, and each of them is at the center of a depression created symmetrically on each of its two surfaces (towards the product and towards the bottom of the tray and the tampon), this depression having the shape of a small bowl, round or even oblong, flattened. The packaging of claim 1, characterized in that the perforations are aligned so as to form rows mutually parallel and parallel to the lateral edges of the false bottom, these rows being able to be offset between them. The packaging of claim 1, characterized in that the average diameter of the perforations is between 0.3 and 5 mm, advantageously between 0.5 and 4 mm, more advantageously between 0.8 and 3 mm, and even more advantageously between 1 and 2.5 mm. The packaging of claim 1, characterized in that the cavities have an average diameter which is at least three times, preferably at least five times the average diameter of the perforations, typically between 3 and 15 times the average diameter of the perforations. The packaging of claim 1, characterized in that the distance between two consecutive perforations is chosen so that there is at least 1 mm, preferably at least 2 mm, on the surface of the false bottom, between the edges of the respective cavities. The packaging of claim 1, characterized in that the distance between the edges of the two consecutive cavities is not more than 1 cm, preferably not more than 8 mm, more preferably not more than 5 mm , and even more preferably is not more than 3 mm. The packaging of claim 1, characterized in that the false bottom is made of the same plastic material that is used for the tray. The packaging of claim 1, characterized in that the false bottom is made of an expanded plastic material such as polystyrene, polypropylene or polyester. The packaging of claim 1, characterized in that the tray, the false bottom, the saturator pad and the outer film are made of thermoplastic materials which are transparent to microwaves and resistant to the heat given off by microwave ovens -waves during their use. The packaging of claim 1, characterized in that the false bottom and the tray are made of a plastic material such as polypropylene or polyester. Packaging according to claim 1 characterized in that the thickness of the plate used for the false bottom is between 1 and 10 mm, preferably between 2 and 8 mm, and even more preferably between 3 and 7 mm. Perforated tray usable as false bottom in the packaging according to claim 1 characterized in that it contains perforations regularly distributed over its surface and covering the entire surface, each perforation being at the center of a depression created symmetrically on each of its two surfaces (towards the product and towards the bottom of the tray and the tampon), this depression having the shape of a small bowl, round or even oblong, flattened.

Images