WO2010103347A1

WO2010103347A1 - A food container with integral heating means

Info

Publication number: WO2010103347A1
Application number: PCT/IB2009/006096
Authority: WO
Inventors: Marius Willie Pieter Venter
Original assignee: Winter Breeze Trading 179 (Pty) Ltd T/A Instant Hot Meals
Priority date: 2009-03-12
Filing date: 2009-06-29
Publication date: 2010-09-16
Also published as: ZA200901776B; CN102348403A

Abstract

This invention discloses a food container (10) with integral heating means to heat food contents contained therein. The container comprises: a receptacle (16) that includes a base, at least one side wall and a removable lid; a water sachet (22), supported, in use, by the base; releasing means (26) connected to the water sachet and being arranged to release the water from the sachet upon the means being actuated by a user,- and a pouch (20) containing a mixture of reagents which react exothermically in the presence of water to produce heat. The container further comprises a holder (18) positionable above the pouch, within the receptacle, for holding the contents to be heated, the holder including a base and at least one side wall (48) extending, a convection passage being defined between the at least one side wall and the surrounding receptacle, the convection passage (52) allowing heat produced below the holder to move by convection to above the holder.

Description

A FOOD CONTAINER WITH INTEGRAL HEATING MEANS

FIELD OF THE INVENTION

This invention relates to a food container with integral heating means for heating food contents within the container, and extends further to a method of manufacturing such a container and to a method for heating food contents contained within such a container.

BACKGROUND TO THE INVENTION

Food is typically heated using devices such as stoves, microwaves and the like. However, recent developments and situations, such as war and food relief programmes in rural areas have presented the need for pre-cooked and sealed meals that can be stored for extended periods at ambient temperature before being heated prior to consumption. These meals are generally referred to as instant hot meals, and typically comprise a container accommodating a food pack to be heated, with a heat source, typically one that makes use of an exothermic reaction, being provided within the container, below the food pack so as to heat pre-cooked food within the food pack just prior to consumption.

In one example, an existing instant hot meal utilises copper sulfate and zinc as reagents to serve as a heat source, no gas is produced by this reaction and zinc sulfate and copper remains after completion of the reaction. Not much heat is produced by this reaction, and therefore a large amount of the reagents are required to heat a small amount of food which is clearly not ideal.

In another example, an existing instant hot meal utilises dehydrated lime (Calcium Oxide) to serve as the heat source when the dehydrated lime is arranged to react with water. Since the exothermic reaction between the water and the dehydrated lime only occurs for a relatively short period of time so as to produce a certain, predetermined amount of heat, the packaging of the instant hot meal becomes important. In particular, the positioning and arrangement of the precooked food, water and dehydrated lime (or other heat producing substance) with respect to one another in a container for the instant hot meal turns out to be an important factor to consider in order to achieve effective and quick heat transfer between a heating source, namely the mixture of dehydrated lime and water, and the pre-cooked food within the container that is to be heated.

Typically, however, conventional instant hot meals are arranged so that the food pack is sealingly fitted to the container in which it is accommodated, which means that the food pack can only be heated from below. This arrangement is not ideal, with the food pack often not getting fully heated. A further disadvantage of this arrangement is that only one type of food, typically rice, within the food pack may be heated, with it accordingly not being possible to premix the rice with a flavourant sauce just prior to the combination being heated.

OBJECT OF THE INVENTION

It is an object of this invention to provide a food container with integral heating means to heat food contents within the container, as well as to a method of manufacturing such a container and to a method for heating food contents contained within such a container, which addresses, at least in part, the abovementioned shortcomings.

SUMMARY OF THE INVENTION

According to the invention there is provided a food container with integral heating means to heat food contents contained therein, the food container comprising:

a receptacle that includes a base, at least one side wall and a removable lid;

a water sachet, containing a predetermined amount of water, supported, in use, by the base;

releasing means connected to the water sachet and being arranged to release the water from the sachet upon the means being actuated by a user;

a pouch containing a mixture of reagents which react exothermically in the presence of water to produce heat, the pouch being accommodated within the receptacle, supported by the water sachet; and a holder positionable above the pouch, within the receptacle, for holding the contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle, the convection passage allowing heat produced below the holder to move by convection to above the holder so as to also heat the contents from above.

In an embodiment of the invention the releasing means extends through the base, at least one side wall, or the removable lid.

In an embodiment of the invention the releasing means is actuated by the user by either pulling the releasing means further through the base, at least one side wall, or the removable lid or pressing the releasing means towards the base, at least one side wall, or the removable lid.

In an embodiment of the invention the at least one side wall of the holder extends away from the base of the holder and terminates in at least one flanged lip.

In an embodiment of the invention the holder includes a removable cover which covers a mouth defined by the at least one side wall while covering and preserving the contents to be heated, the cover being removed just prior to initiation of the exothermic reaction.

In an embodiment of the invention the convection passage is a gap, defined between the at least one flanged lip and the surrounding receptacle, formed between a seat defined in an upper part of the receptacle and at least one wing of the at least one flanged lip, the at least one wing standing proud of the flanged lip so as to define an enlarged convection passage gap in the region proximate the at least one wing; alternatively or additionally, the convection passage comprises a plurality of convection channels between ridges defined in the at least one side wall of the receptacle, the channels running between the base and the removable lid so as to further facilitate the produced heat to move by convection from below the holder to above the holder.

In an embodiment of the invention the mixture of reagents comprises finely powdered Magnesium metal (Mg(s)) mixed together with finely powdered Iron metal (Fe(s)) and an inert filler, the mixture being housed in a pouch that is pervious so as to allow water released from the sachet to operatively come into contact with the mixture of reagents within the pouch. The amount of water in the water sachet is predetermined and pre-packed so that the contents to be heated can be heated up to between about 100 ⁰C and 120 ⁰C within about 30 to 45 seconds by means of convection heat transfer, which occurs within the receptacle when the removable lid is in place, as a result of a predetermined rate of reaction.

In an embodiment of the invention the releasing means arranged to release the water from the sachet is a pull-tab. The pull-tab is displaceable between a first position wherein a gripping portion of the pull-tab only partially extends through either the base, at least one side wall, or removable lid; and a second position wherein a further portion of the pull-tab, which is connected to the water sachet inside the receptacle and concealed prior to initiation of the exothermic reaction by the base, at least one side wall, and removable lid, is located outside the receptacle. The water sachet is supported above and attached to the base so that part of the water sachet which is connected to the pull-tab is torn from a remaining part of the sachet when the pull-tab is displaced by the user to pull open the sachet.

In an embodiment of the invention the contents to be heated include pre-cooked food which is sterilized, the pre-cooked food is pre-packed and stored, until subsequent heating by convection, in the holder. Therefore, the holder, in use, is suspended above the receptacle without the base of the holder coming into direct contact with the pouch. Alternatively, conductive contact between the base and the pouch may occur in addition to convection taking place.

In an embodiment of the invention an additional food pack, for accommodating additional precooked food content that can be mixed into the contents of the holder prior to the initiation of the exothermic reaction, is provided to fit within the receptacle; alternatively or additionally, accesory packets and utensil packets are also accommodated within the receptacle.

In an embodiment of the invention the removable lid includes a roof that is raised relative to an upper edge of the receptacle, the raised roof defining a heating chamber above the holder, heat produced as a result of the exothermic reaction slowly dissipates from the receptacle, and in particular from the heating chamber, through a release aperture formed in the raised roof so that the contents can be ready for consumption after approximately 6 to 8 minutes after the user pulls open the water sachet.

In an embodiment of the invention the receptacle is manufactured from recyclable materials that can withstand the temperatures generated by the exothermic reaction.

In accordance with a further aspect of the invention there is provided a method of manufacturing a food container, the method comprising: providing a receptacle that includes a base, at least one side wall and a removable lid;

filling a water sachet with a predetermined amount of water, and locating the sachet, after sealing thereof, in a position supported by the base;

providing releasing means which is connected to the water sachet and arranged to release the water from the sachet upon the means being actuated by a user;

providing a pouch containing a mixture of reagents which react exothermically in the presence of water to produce heat, the pouch being accommodated within the receptacle, supported by the water sachet; and

providing a holder and positioning the holder above the pouch, within the receptacle, the holder being adapted to hold food contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle, the convection passage allowing heat produced below the holder to move by convection to above the holder so as to also heat the contents from above.

In accordance with yet a further aspect of the invention there is provided a method for heating food contents contained in a food container, the food container comprising:

a receptacle that includes a base, at least one side wall and a removable lid;

a pouch containing a mixture of reagents which react exothermically in the presence of water to produce heat, the pouch being accommodated within the receptacle, supported by the water sachet; and

a holder positionable above the pouch, within the receptacle, for holding the contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle,

the method comprising:

securing the removable lid to the receptacle with the holder positioned above the pouch;

actuating the releasing means, thereby tearing the sachet open to release the water;

allowing water released from the sachet to react with the mixture of reagents so as to produce heat below the holder; and

allowing the heat to be transferred by convection from below the holder to above the holder through the convection passage so as to also heat the contents from above.

In accordance with an embodiment of this yet further aspect of the invention the holder comprises a removable cover covering pre-cooked food to be heated in the holder, the method comprising removing the removable lid of the receptacle, removing the cover of the holder and replacing the removable lid prior to the releasing means being actuated to initiate the exothermic reaction.

In accordance with another embodiment of this yet further aspect of the invention an additional food pack accommodating an additional pre-cooked food content is pre-packed within the receptacle, the method including removing the removable lid of the receptacle, removing the cover of the holder, opening the additional food pack, adding the additional pre-cooked food content to the pre-cooked food in the holder, and replacing the removable lid prior to the releasing means being actuated to initiate the exothermic reaction.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is now described, by way of example, with reference to the accompanying non-limiting diagrammatic drawings. In the drawings: Figure 1 shows a partially cutaway perspective view of a food container with integral heating means to heat food contents contained therein in accordance with an embodiment of the invention, an additional food pack and utensil being shown separately;

Figure 2 shows a cross sectional side view of the food container of Figure 1 ;

Figure 3 shows an exploded perspective view of the food container of Figure 1 , with the contents thereof illustrated in stacked relation to one another;

Figure 4 shows a perspective view of a receptacle of the food container of Figure 1 with a water sachet fitted therein and means to release the water from the water sachet upon the means being pulled away from the receptacle by a user;

Figure 5 shows a perspective view of a holder of the food container of Figure 1 holding contents to be heated;

Figure 6 shows a perspective view of the holder of Figure 5 suspended above a concealed pouch and water sachet which is located in the receptacle, with food contents of the additional food pack of Figure 1 being added to the contents to be heated in the holder;

Figure 7 shows a diagrammatic representation of the sequence of operations carried out in a method of manufacturing the food container of Figure 1 ; and

Figure 8 shows a diagrammatic representation of the sequence of operations carried out in a method for heating food contents contained within the food container of Figure 1.

DETAILED DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals generally indicate like components, unless otherwise indicated. Unless inconsistent with the context, an expression which denotes any gender includes the other gender.

In the description below, a food container 10 with integral heating means for heating food contents within the container 10, a method of manufacturing the container 10, and a method for heating food contents contained within the food container 10, will be described. Figures 3 to 6 of the drawings illustrate the food container 10 or components thereof, according to one non- limiting embodiment of the invention, prior to initiation of an exothermic reaction within the container; while Figure 1 and 2 illustrate the food container 10, according to one non-limiting embodiment of the invention, after initiation of the exothermic reaction within the container so as to heat food contents contained therein.

Figure 1 of the drawings shows a perspective view, including a cutaway portion, of the food container 10. An additional food pack 12 and eating utensil 14 are shown separately and are typically also packed in a receptacle 16 of the container 10 together with a holder 18, pouch 20 and water sachet 22 when prepared for shipping. The above contents, in accordance with this embodiment of the invention, are normally pre-packed in stacked relation to one another in the container 10 as shown in Figure 3 of the drawings.

The water sachet 22 is, typically, but not necessarily, fixed to a base 24 of the receptacle 16. Such attachment may be achieved by means of riveting part of the sachet 22 to the base 24 or by other means known in the art to ensure that the water sachet 22 is supported above the base 24 of the receptacle 16 and attached to the base 24. The attachment is necessary since releasing means or a pull-tab 26, arranged to release the water from the sachet 22 and which, preferably, but not necessarily, extends through a side wall 30 of the receptacle 16, can only be actuated to release water from the sachet if part of the sachet 22 which is connected to the pull- tab 26 is torn from part of the sachet 22 remaining secured against the base 24 when the pull- tab 26 is displaced by a user to pull open the sachet 22. It is also envisaged that the releasing means may include other devices adapted to tear open the sachet to release the water therefrom upon actuation by the user. Such an alternative device could, for example, include a push button (not shown) that can be depressed to urge a sharpened projection to pierce the sachet.

Although displacement of the pull-tab 26 is not shown in detail, Figure 4, illustrates how the pull- tab 26 is displaceable between a first position wherein a gripping portion 28 of the pull-tab 26 only partially extends through a side wall 30 of the receptacle 16; and a second position (not shown) wherein a further portion 32 of the pull-tab 26, which is connected to the water sachet 22 inside the receptacle 16 and concealed within the container 10 prior to initiation of the exothermic reaction, is located outside the container 10. This displacement of the pull-tab 26 ensures that the sachet 22 is torn, preferably, along lines of weakness 33 provided on the sachet 22 so as to allow water to flow out of the sachet 22 into the receptacle 16. The amount of water in the sachet 22 is predetermined and pre-packed so that food contents to be heated within the container 10 can be heated up to between about 100 ⁰C and 120 ⁰C within about 30 to 45 seconds by means of convection heat transfer occurring within the receptacle 16 as a result of a predetermined rate of reaction. Obviously heat transfer can only occur within the container 10 if a removable lid 34, adapted to snap fit onto an upper edge 36 of the receptacle 16, is secured to the receptacle 16. The lid 34 includes a roof 38 that is raised relative to the upper edge 36 of the receptacle 16, the raised roof 38 defining a heating chamber 40 above the holder 18 as shown in Figure 2 of the drawings. A release aperture 42 is also formed in the roof 38 of the lid 34 so that heat produced as a result of the exothermic reaction can slowly dissipate from the closed heating chamber 40 in the closed receptacle 16. This allows the contents in the container 10 to be ready for consumption after approximately 6 to 8 minutes after the user pulls open the water sachet 22.

Typically, the pouch 20 is accommodated within the receptacle 16, supported by the water sachet 22 as shown in Figures 1 to 3. The pouch 20 contains a mixture of reagents 44 which react exothermically in the presence of water to produce heat Q. The applicant believes that finely powdered Magnesium metal (Mg(s)) mixed together with finely powdered Iron metal (Fe(s)) and an inert filler produces sufficient heat Q to allow food contents to be heated up in a short period of time. The chemical reaction is:

Fe(s) Mg(S) + 2H₂O → Mg(OH)₂ + H₂ + Q

To activate or initiate the reaction a predetermined amount of water, released from the sachet 22, is brought into contact with the mixture of reagents in the pouch 20. Although, only a small amount of Iron metal (Fe(S)) forms part of the mixture, the Iron functions as a catalyst for the above chemical reaction as it is initially oxidised, and then reduced back to its elemental form as the Magnesium is oxidised and sends its two valence electrons to Iron.

Alternative reagents capable of producing a similar reaction rate and a similar amount of heat in a safe and affordable way, and which can be used with the container 10 in accordance with this invention to heat contents contained therein is believed to also fall within the spirit and scope of the invention. It is also foreseeable that the mixture of reagents 44 may be arranged loosely within the receptacle 16, but in this invention, the mixture 44 is housed in a pouch 20 that is pervious so as to allow water released from the sachet 22 to operatively come into contact with the mixture 44 within the pouch 20.

A holder 18 for holding food contents to be heated in accordance with the invention is shown in Figure 5 of the drawings. In Figures 2, 3 and 6, the holder 18 is shown above the pouch 20, and positioned within the receptacle 16. The holder 16 includes a bed 46, side walls 48 and a flanged lip 50 extending from a peripheral edge of the side walls 48. A convection passage 52 is defined between the flanged lip 50 and the surrounding receptacle 16 so that hea t Q produced below the holder 18 can move by convection through the convection passage to above the holder 18 into the heating chamber 40 so as to also heat the food contents from above. The holder 18 includes a removable cover 54, which covers an open end 55 defined between the side walls 48 of the holder 18, while covering and preserving the contents to be heated, the cover 54 is removed just prior to the initiation of the exothermic reaction.

Figures 2 and 6 show how the convection passage 52 is a gap 56, defined between the flanged lip 50 and the surrounding receptacle 16, formed between a seat 58 defined in an upper part 60 of the receptacle 16 and a wing 62 of the flanged lip 50. The wing 62 stands proud of the flanged lip 50, or is curved upwardly relative to the flanged lip 50, so as to define an enlarged convection passage gap 56 in the region proximate the wing 62.

The convection passage 52 in accordance with this embodiment of the invention further includes a plurality of channels 64 defined between ridges in the side wall 30 of the receptacle 16. The channels 64 run between the base 24 and the lid 34 so as to further facilitate the produced heat Q to move by convection from below the holder 18 to above the holder 18, i.e. into the heating chamber 40. It will be appreciated that the container 10 would also be able to function to heat contents contained therein with only the gap 56 through which heat Q can move to the heating chamber 40. Obviously, the convection passage 52 may comprise a plurality of gaps 56 and/or channels 64 formed between the receptacle 16 and the heating chamber 40 as shown in Figure 6 of the drawings where gaps 56 are formed below corners of the flanged lip 50 of the holder 18 and channels 64 are formed in the side walls 30 of the receptacle 16. The gaps 56 and channels 64 may also take a variety of shapes and configurations and may be provided at different positions between the receptacle 16 and the heating chamber 40.

The contents to be heated include pre-cooked food which is sterilized, the pre-cooked food is pre-packed and stored, until subsequent heating by convection, in the holder 18. The holder 18, in use, is suspended above the receptacle 16 without the base 46 of the holder 18 coming into direct contact with the pouch 20. Alternatively, conductive contact between the base 46 and the pouch 20 may occur in addition to convection taking place. It is also envisaged that the contents to be heated which are pre-packed in the holder may include water.

In this embodiment of the invention an additional food pack 12, which accommodates additional pre-cooked food content that can be mixed into the food contents of the holder 18 prior to the initiation of the exothermic reaction, is provided to fit within the receptacle 16. Alternatively or additionally, accesory packets (not shown) containing for example, shelf-stable items such as, coffee, sugar, milk powder, cereals, bread, desert, dried fruit and the like; and utensil packets including, for example, matches, toilet tissue, gum and condoms may also be accommodated within the receptacle 16. The receptacle 16 and holder 18 are also manufactured from recyclable materials such as acrylonitrile-butadiene-styrene copolymer (ABS food grade) that can withstand the temperatures generated by the exothermic reaction. Other materials that are also capable of withstanding the temperatures generated may also be used.

In accordance with a further aspect of the invention there is provided a method 100 of manufacturing a food container 10 as depicted in Figure 7 of the drawings which illustrates a diagrammatic representation of the sequence of operations carried out in the method 100.

The method 100 comprises providing a receptacle 16 that includes a base 24, at least one side wall 30 and a removable lid 34 as indicated by block 102. The method 100 further comprises filling a water sachet 22 with a predetermined amount of water, and locating the sachet 22, after sealing it, in a position supported by the base 24 when the lid 34 is removed as indicated by block 104. Thereafter, the method 100 includes providing releasing means 26 which is connected to the water sachet 22 and arranged to release the water from the sachet 22 upon the releasing means 26 being actuated by a user as indicated by block 106. Thereafter, the method 100 includes providing a pouch 20 containing a mixture of reagents 44 which react exothermically in the presence of water to produce heat, the pouch 20 being accommodated within the receptacle 16, supported by the water sachet 22 as indicated by block 108. The method terminates by providing a holder 18 and positioning the holder 18 above the pouch 20, before replacing the lid 34, within the receptacle, the holder 18 being adapted to hold food contents to be heated, the holder 18 including a base 46 and at least one side wall 48, a convection passage 52 being defined between the at least one side wall 48 and the surrounding receptacle 16, the convection passage 52 allowing heat produced below the holder 18 to move by convection to above the holder 18 so as to also heat the contents from above as indicated by block 110.

In accordance with yet a further aspect of the invention there is provided a method 200 for heating contents contained in the container 10 as depicted in Figure 8 of the drawings which illustrates a diagrammatic representation of the sequence of operations carried out in the method 200. The method 200 comprises securing the removable lid 34 to the receptacle 16 with the holder 18 positioned above the pouch 20 as indicated by block 202. The method 200 further comprises actuating the releasing means 26, thereby tearing the sachet 22 to release the water as indicated by block 204. Thereafter, the method 200 includes allowing water released from the sachet 22 to react with the mixture of reagents 44 so as to produce heat Q below the holder 18 as indicated by block 206. The method terminates by allowing the heat Q to be transferred by convection from below the holder 18 to above the holder 18, into a heating chamber 40, via the convection passage 52/56/64 so as to also heat the contents from above as indicated by block 204.

The holder 18, in accordance with an embodiment of this yet further aspect of the invention, comprises a removable cover 54 covering pre-cooked food to be heated in the holder 18, the method 200 thus comprising removing the lid 34 of the receptacle 16, removing the cover 54 of the holder 18 and replacing the lid 34 prior to the pull-tab 26 being pulled through the side wall 30 to initiate the exothermic reaction. Pre-cooked food held in an additional food pack 12 may also be added to the food in the holder 18, to add for instance flavour thereto, prior to the pull- tab 26 being pulled through the side wall 30 to initiate the exothermic reaction.

While a preferred embodiment of the invention is shown and described, it will be understood that it is not intended to limit the extent of the invention, but rather it is intended to cover all modifications and alternate methods, including: moulds and methods for producing the container 10 and components thereof, and processes for heating food contents contained within the container 10 falling within the spirit and the scope of the invention.

The applicant believes that the food container 10 of the present invention, at least in part, addresses shortcomings in conventional instant hot meal methods in that the container 10 provides a neat, but tough and easily heatable, way in which a cooked meal can be provided to people who find themselves in situations, such as, war or who are dependant on food relief programmes.

Claims

1. A food container with integral heating means to heat food contents contained therein, the food container comprising:

a receptacle that includes a base, at least one side wall and a removable lid;

a holder positionable above the pouch, within the receptacle, for holding the contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle, the convection passage allowing heat produced below the holder to move by convection to above the holder so as to also heat the contents from above.

2. The food container of claim 1 , wherein the releasing means extends through the base, at least one side wall, or the removable Nd.

3. The food container of claim 2, wherein the releasing means is a pull-tab which is actuated by the user to by pulling to displace the pull-tab from a first position wherein a gripping portion of the pull-tab only partially extends through either the base, at least one side wall, or removable lid; and a second position wherein a further portion of the pull- tab, which is connected to the water sachet inside the receptacle and concealed prior to initiation of the exothermic reaction by the base, at least one side wall, and removable lid, is located outside the receptacle.

4. The food container of claim 3, wherein the water sachet is supported above and attached to the base so that part of the water sachet which is connected to the pull-tab is torn from a remaining part of the sachet when the pull-tab is displaced by the user to pull open the sachet.

5. The food container as claimed in any one of the preceding claims, wherein the at least one side wall of the holder extends away from the base of the holder and terminates in at least one flanged lip.

6. The food container as claimed in any one of the preceding claims, wherein the holder includes a removable cover which covers a mouth defined by the at least one side wall while covering and preserving the contents to be heated, the cover being removed just prior to initiation of the exothermic reaction.

7. The food container as claimed in claim 5 or claim 6, wherein the convection passage is a gap, defined between the at least one flanged lip and the surrounding receptacle, formed between a seat defined in an upper part of the receptacle and at least one wing of the at least one flanged lip.

8. The food container of claim 7, wherein the at least one wing stands proud of the flanged lip so as to define an enlarged convection passage gap in the region proximate the at least one wing.

9. The food container as claimed in any one of the preceding claims, wherein the convection passage comprises a plurality of convection channels defined between ridges in the at least one side wall of the receptacle, the channels running between the base and the removable lid so as to further facilitate the produced heat to move by convection from below the holder to above the holder.

10. The food container as claimed in any one of the preceding claims, wherein the pouch is pervious so as to allow water released from the sachet to operatively come into contact with the mixture of reagents within the pouch.

11. The food container as claimed in any one of the preceding claims, wherein the mixture of reagents comprises finely powdered Magnesium metal (Mg(S)) mixed together with finely powdered Iron metal (Fe(s)) and an inert filler.

12. The food container as claimed in any one of the preceding claims, wherein the amount of water in the water sachet is predetermined and pre-packed so that the contents to be heated can be heated up to between about 100 ⁰C and 120 ⁰C within about 30 to 45 seconds by means of convection heat transfer, which occurs within the receptacle when the removable lid is in place, as a result of a predetermined rate of reaction.

13. The food container as claimed in any one of the preceding claims, wherein the holder, in use, is suspended above the receptacle without the holder coming into direct contact with the pouch.

14. The food container as claimed in any one of the preceding claims, wherein the contents to be heated include pre-cooked food which is sterilized, the pre-cooked food being prepacked and stored, until subsequent heating, in the holder.

15. The food container as claimed in any one of claims 1 to 13, which includes an additional food pack for accommodating an additional pre-cooked food content, which can be mixed into the contents of the holder prior to the initiation of the exothermic reaction.

16. The food container as claimed in any one of the preceding claims, wherein the removable lid includes a roof that is raised relative to an upper edge of the receptacle, the raised roof defining a heating chamber above the holder.

17. The food container as claimed in claim 16, including a release aperture formed in the roof of the lid allowing heat produced to slowly dissipate from the receptacle so that the contents can be ready for consumption after about 6 to 8 minutes after the water has been released from the sachet.

18. The food container as claimed in any one of the preceding claims, wherein the receptacle includes accesory packets and utensil packets.

19. The food container as claimed in any one of the preceding claims, wherein the receptacle is manufactured from a recyclable food grade acrylonitrile-butadiene-styrene copolymer that can withstand the temperatures generated by the exothermic reaction.

20. A method of manufacturing a food container, the method comprising:

providing a receptacle that includes a base, at least one side wall and a removable lid; filling a water sachet with a predetermined amount of water, and locating the sachet, after sealing thereof, in a position supported by the base;

providing a holder and positioning the holder above the pouch, within the receptacle, before securing the removable lid to the receptacle, the holder being adapted to hold food contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle, the convection passage allowing heat produced below the holder to move by convection to above the holder so as to also heat the contents from above.

21. A method for heating food contents contained in a food container, the food container comprising:

a receptacle that includes a base, at least one side wall and a removable lid;

a holder positionable above the pouch, within the receptacle, for holding the contents to be heated, the holder including a base and at least one side wall, a convection passage being defined between the at least one side wall and the surrounding receptacle, the method comprising:

22. The method as claimed in claim 21 , wherein the holder comprises a removable cover covering pre-cooked food to be heated in the holder, the method comprising removing the removable lid of the receptacle, removing the cover of the holder and replacing the removable lid prior to the releasing means being actuated to initiate the exothermic reaction.

23. The method as claimed in claim 22, wherein an additional food pack accommodating an additional pre-cooked food content is pre-packed within the receptacle, the method including removing the removable lid of the receptacle, removing the cover of the holder, opening the additional food pack, adding the additional pre-cooked food content to the pre-cooked food in the holder, and replacing the removable lid prior to the releasing means being actuated to initiate the exothermic reaction.