WO2009103152A1

WO2009103152A1 - Food packaging system

Info

Publication number: WO2009103152A1
Application number: PCT/CA2009/000191
Authority: WO
Inventors: Denis Mercure
Original assignee: 9136-2871 Quebec Inc.
Priority date: 2008-02-18
Filing date: 2009-02-17
Publication date: 2009-08-27

Abstract

The food packaging system has a pan having a plurality of cups each having a bottom and a rim, and a pan panel extending around and interconnecting the rims of each cup; and a tray shaped for receiving the pan therein, the tray having a bottom panel with a plurality of insulating sections, each insulating section receiving a bottom of a corresponding cup when the pan is received and at least one opening located between selected ones of the insulating sections, and walls extending upwardly around the bottom panel and engaging the periphery of the pan panel when the pan is received in the tray. The walls are configured to reduce convection movement of hot air around the pan and during baking whereas the at least one opening is configured to favor convection movement of the hot air in an internal section, between cups.

Description

FOOD PACKAGING SYSTEM

PRIORITY CLAIM

[0001] This application claims priority of United States provisional application no. 61/029,442, filed February 18, 2008, by applicant, the contents of which are hereby incorporated by reference.

FIELD

[0002] The specification describes a food packaging system for baking frozen-dough food products from a frozen state.

BACKGROUND [0003] It is well known in the art that baking dough products such as muffins or cupcakes is done using a cooking device typically referred to as a "muffin pan", which has a plurality of interspaced cups (typically 4 to 12) with a generally flat panel extending around and interconnecting the rims of each ones of the cups. Such muffin pans are available in metal and plastic materials.

[0004] Although satisfactory to a certain degree, the aforementioned pans had several limitations. For instance, it is well known that during baking, a higher concentration of heat is exposed to the bottoms of the cups, which tends to lead to burning of the lower portion of the dough products. Also, during baking, convection movements of hot air occur in the oven which bring heat to the cups. Because of the presence of the flat panel interconnecting the cups, the convection movements of the hot air is directed around the periphery of the flat panel, which tends to expose the portions of the cups which are closer to the periphery (outer portions) of the flat panel to quicker baking than the portions of the cups which are located inwardly from the periphery (i.e. between adjacent cups). This leads to deformation in the baked dough products, such as sloping tops, among other inconveniences. [0005] The aforementioned inconveniences are known, but are typically tolerated when baking non-frozen dough. However, these inconveniences are amplified when attempting to bake dough products from a frozen state to a point of unacceptability.

[0006] For these and other reasons, products such as muffins and cupcakes are not provided among the many packaged frozen-dough food products readily available in grocery stores.

[0007] There thus remained room for improvement.

SUMMARY

[0008] One solution is the provision of a food packaging system which includes a tray which receives the pan therein. In accordance to one aspect, the problem of occurrences of burning of the dough products in the bottoms of the cups can be addressed by providing insulating sections in a bottom panel of the tray which receive and provide insulation to the bottoms of the cups. In accordance to another aspect, the problem of uneven cooking between outer portions of the cups and inner portions of the cups (relative to the periphery of the pan) can be addressed by configuring the tray in a manner to restrict the convection flow of hot air around the periphery of the pan relatively to a convection flow of hot air occurring between adjacent cups, internally of the pan. Both these aspects can be addressed at once using a tray having the characteristics taught herein. Furthermore, using a food packaging system which includes both a pan and a tray, ready- for-cooking frozen-dough food products such as muffins and cupcakes can be made available to consumers.

[0009] In accordance with one aspect, there is provided a food packaging system for baking frozen-dough food products from a frozen state, the food packaging system comprising: a pan having a plurality of interspaced cups each having a bottom and a rim, and a pan panel extending around and interconnecting the rims of each cup; and a tray shaped for receiving the pan therein, the tray having a bottom panel with insulating sections each receiving a bottom of a corresponding cup when the pan is received, and at least one opening located between selected ones of the insulating sections, and walls extending upwardly around the bottom panel and engaging a periphery of the pan panel when the pan is received in the tray, the walls being configured to reduce convection movement of hot air around outer portions of the cups, adjacent the periphery of the pan, during baking, whereas the at least one opening is configured to relatively favor convection movement of the hot air around internal portions of the cups, away from the periphery of the pan.

[0010] In accordance with another aspect, there is provided a baking tray for a muffin pan having 6 or more interspaced cups each having a bottom and a rim, and a frusto-conical wall extending therebetween, and a pan panel extending around and interconnecting the rims of each cup, the pan panel having a periphery, and the cups having outer portions adjacent the periphery and inner portions oriented away from the periphery, the baking tray comprising : a generally rectangular body shaped to receive the muffin pan therein and having a flat bottom and walls extending upwardly from the flat bottom and engaging the periphery of the pan panel when the latter is received therein, the flat bottom having 6 or more interspaced insulating sections configured to receive the bottoms of corresponding cups and provide insulation thereto when the pan is received in the tray, and openings, the tray being configured to control convection movement of hot air during baking in a manner that the inner portions of the cups are submitted to a comparable amount of heat transfer than the outer portions of the cups.

[0011] In accordance with another aspect, there is provided a food heating container comprising: a heat transfer tray having wall panels with at least one heat transfer opening extending therethrough and at least one full section, the at least one opening and at least one opening-free section defining a heat transfer configuration, the wall panels defining a storage space in the heat transfer tray; and a food containing insert insertable in the storage space, having an upper face, an opposed lower face and at least one food containing well defined therein, the at least one heat transfer opening and the at least one opening-free section being respectively aligned with at least one section of the food containing insert for accelerating heat transfer and at least one section of the food containing insert for reducing heat transfer. [0012] In accordance with another aspect, there is provided a heat transfer tray in combination with a heatable food tray, the heat transfer tray comprising: a heatable transfer tray body defining a storage space and having a heat transfer pattern including at least one heat transfer opening extending therethrough and at least one opening-free section; and the heatable food tray being at least partially insertable in the storage space and having a food tray body defining at least one food well with a food well outer surface, the at least one heat transfer opening and the at least one opening-free section being respectively aligned with predetermined sections of the food well outer surface for providing a controlled heat supply thereto.

[0013] In accordance with another aspect, there is provided a method for controlling heat transfer in a heatable food tray, the method comprising: inserting, in a storage space of a heat transfer tray, the heat food tray, the heat transfer tray having at least one heat transfer opening extending therethrough and at least one opening free section, the at least one opening and at least one opening free section defining a heat transfer pattern; aligning the at least one heat transfer opening free section with a first section of the heat food tray for reducing heat transfer towards said first section; and aligning the at least one heat transfer opening with a second section of the heat food tray for promoting heat transfer towards said second section.

[0014] Many further features and combinations thereof concerning the present improvements will appear to those skilled in the art following a reading of the instant disclosure.

[0015] It will be understood that although the word "convection" in the field of baking is often used to refer to ovens having forced convection, i.e. one or more fans, the word "convection" is given its plain and ordinary meaning herein, and refers to heat transfer between a fluid (air) and a solid, either from natural convection movement of the heated air which rises, and/or from forced air movement.

DESCRIPTION OF THE FIGURES

[0016] In the figures, [0017] Fig. 1 is a perspective view of an example of the food packaging system;

[0018] Fig. 2 is a perspective view of a tray of the food packaging system of Fig. 1;

[0019] Fig. 3 is a top plan view of the tray of Fig. 2;

[0020] Fig. 4 is cross-sectional view taken along lines 4-4 of Fig. 3;

[0021] Fig. 5 is cross-sectional view taken along lines 5-5 of Fig. 3;

[0022] Fig. 6 is a top plan view of the food packaging system of Fig. 1; and

[0023] Fig. 7 is a side elevation view of the food packaging system of Fig. 1.

DETAILED DESCRIPTION

[0024] Fig.l illustrates an example of a food packaging system 5 having a tray 10 receiving a pan 30 therein. In this embodiment, the pan 30 is a muffin pan 30a similar to the muffin pans which are widespread in the art and which can be used to bake muffins or cupcakes, for example. The muffin pan 30a has a plurality of interspaced cups 7a, 7b, 7c, 7d, 7e, 7f, which in this case are equally interspaced in an arrayed configuration. Each of the cups 7a, 7b, 7c, 7d, 7e, 7f, has a cylindrical or frusto-conical (i.e. truncated cone) shaped wall and a flat bottom, as is well known in the art, and a rim 8a, 8b, 8c, 8d, 8e, 8f. It is general knowledge in the art that muffin pans can have a different number of cups. The muffin pan 30a also has a generally flat pan panel 9, which both surrounds and interconnects the cups 7a, 7b, 7c, 7d, 7e, 7f, in the arrayed configuration, and which is also used to manipulate the muffin pan 30a. In the illustrated embodiment, the packaging system 5 can be sold wrapped as a whole with a frozen-dough food product 15 such as frozen muffin or cupcake paste provided inside the cups 7a, 7b, 7c, 7d, 7e, 7f. In use, the consumer can simply remove the wrapped food packaging system 5 (wrapping not shown) from the freezer, remove the wrapping (not shown), and place the food packaging system 5 directly in the oven for cooking. [0025] The tray 10 helps provide an even cooking of the food product 15 by directing the hot air movement, either forced or natural, evenly around the frusto-conical walls of the cups in the oven, as will be detailed further below, so that the convection heat transfer can occur evenly and lead to an even cooking of the food product 15. More particularly, each cup 7a, 7b, 7c, 7d, 7e, 7f, or more particularly each frusto-conical wall thereof, has an outer portion 17a, 19a which is adjacent, or oriented generally toward the periphery 21 of the pan 30, and an inner portion 17b, 19b, which is oriented generally away from the periphery 21 of the pan 30. Without the tray 10, the movement of hot air, and the resulting convection heat transfer, is considerably greater in the outer portions 17a, 19a than in the inner portions 17b, 19b, because the ascending hot air has to go around the obstacle caused by the flat panel 9 which interconnects the cups - there is thus a given speed of flow of air at the periphery, whereas there is a zero speed through the center, because the hot air cannot pass through the flat panel 9.

[0026] Turning now to Fig. 2, the heat transfer tray 10 is generally rectangular in shape. The heat transfer tray 10 includes a tray body 11 with a generally flat bottom wall 12, or panel surrounded by peripheral walls 14 extending upwardly from the bottom wall 12. Both the bottom wall 12 and the peripheral wall 14 includes a plurality of gas and heat openings 16, also called hot air or convection openings, defining a path for the circulation of hot air referred to herein as a heat transfer pattern or configuration 18, or convection path, as it will be detailed below.

[0027] More particularly, the tray body 11 defines a storage space 20 therein with an opening 22 defined by the upper edges of the peripheral walls 14. In use, the upper edges of the peripheral walls come into engagement with the periphery 21 of the muffin pan 30a (see Fig. 1).

[0028] In the embodiment shown, several gas and heat openings 16 are defined in the bottom wall 12 and in the peripheral walls 14 and are in fluid communication with the storage space 20. [0029] The general function of the tray 10 is to restrict the flow of hot air around the periphery 21 (Fig. 1) of the pan 30, and the corresponding convection heat transfer, in a manner that it becomes comparable to the amount of air flow circulating in the inner portions of the pan 30, and to the corresponding convection heat transfer at these locations. Another way to address this is to create openings through the flat panel 9 of the pan 30, in the inner portions thereof, though this is not preferred as it will appear from the discussion provided below.

[0030] The openings 16 defined in the heat transfer tray 10 thus provide restricted hot air passages for the periphery and include a first set of openings 16a provided in the bottom wall 12 of the heat transfer tray 10, each opening 16a defines an area lying in a plane substantially parallel to the bottom wall 12. A second set of openings 16b is provided, wherein each opening 16b defines an area lying in a plane substantially parallel to the peripheral wall 14 wherein it is defined. The second set of openings 16b acts as peripheral outlets of a restricted surface area to the hot air path. The second set of openings is optional, and can alternately be provided in the form of spacings between the walls of the tray 10 and the edges of the pan 30. The plurality of openings 16 thus allow gas (air) to flow through the heat transfer tray in several directions substantially perpendicular to the wall 12, 14 in which they are defined. In the embodiment shown, the openings 16b in the peripheral walls lie in a single horizontal plane, i.e. the openings 16b are at the same distance from the bottom wall 12 of the heat transfer tray 10. However, it is appreciated that in alternate embodiments, the configuration of the openings 16b can vary in each of the peripheral walls 14.

[0031 ] The tray 10 can be made of an insulating material, such as a paper-based material like paperboard or cardboard. A plurality of insulating section 25a, 25b, 25c, 25d, 25e, 25f, also called opening-free sections, are located at predetermined positions in the bottom wall panel 12, corresponding to the positions of the bottoms of the cups 7a, 7b, 7c, 7d, 7e, 7f (see Fig. 1), and serve both to support the muffin pan 30a and to provide insulation to the bottoms of the cups 7a, 7b, 7c, 7d, 7e, 7f to reduce the likelihood of burning the bottom portion of the products during baking. In alternate embodiments, if the tray is omitted because apertures are provided in the internal portions of the pan to favour internal convection heat transfer, it would be preferred that insulating elements be provided under the bottoms of the cups to reduce the likelihood of burning the bottom portion of the dough products.

[0032] In the particular configuration described herein, relatively large openings 23a and 23b are provided between selected ones of the insulating sections 25a, 25b, 25c and 25d; and 25c, 25d, 25e and 25f, respectively. In the illustrated embodiment, these openings 23a and 23b are intended to provided as little restriction to air movement as possible in the internal portion of the pan 30. It will be understood that the configuration of the tray 10, including more particularly the configuration of the peripheral walls 14 of the tray 10, restricts the flow of convection air around the outer portions 17a, 19a of the cups. On the other hand, the openings 23a and 23b provide minimal restriction to convection air flow around the inner portions 17b, 19b of the cups. The overall result is that the restricted flow of convection air around the outer portions 17a, 19a of the cups can be comparable to the flow of convection air circulating through the openings 23a and 23b, and exposed to the inner portions 17b, 19b, of the cups. As discussed above, an aim is that the convection heat transfer resulting from peripheral hot air circulation be comparable to the convection heat transfer resulting from internal hot air circulation.

[0033] Referring now generally to Figs. 2 to 5, the storage space 20 is defined to receive therein a food tray 30 (also called a pan), such as and without being limitative, a muffin tray, a baking tray, a frozen meal tray, a pan and the like. The food tray 30 is inserted in the storage space 20 for heating purposes, as it will be described in more details below.

[0034] In the embodiment shown, the heat transfer tray 10 has a heat transfer pattern 18 designed to receive a muffin tray, as food tray 30, with six baking wells 32, also called cups, in its storage space 20. In an alternate embodiment, the wells may be equally spaced. The food tray 30 and its wells 32 are shown in dotted lines in Figs. 6 and 7. In another embodiment (not shown), the food tray may comprise more or less wells.

[0035] More particularly, the food tray 30 includes a substantially planar top portion 34, or pan panel, from which the wells 32 protrude. The top portion 34 has an upper surface and an opposed lower surface from which the baking wells 42 project. The top portion 32 terminates with a peripheral edge 36.

[0036] For a muffin tray, each well 32, or cup, includes a frustoconical sidewall 38 (i.e. truncated conical) extending downwardly with the larger end open upwardly. The frustoconical sidewall 38 blends into a closed end such as the generally circular bottom surface 40 which closes the bottom of the well 32. Each well 32 forms a cavity 42 adapted to contain the food product to be heated. In another embodiment, the muffin tray may have a rim and the panel extending around and interconnecting the rim of each cup.

[0037] The wells 32 are spaced-apart or interspaced from one another and gas and heat circulation channels 44, part or the hot air path, are defined between the sidewalls 38. hi the embodiment shown, one gas and heat circulation channel 44 extends longitudinally while two gas and heat circulation channels 44 extend transversally between the wells 32.

[0038] The food tray 30 is designed to be inserted in the storage space 20 of the heat transfer tray 10 with the peripheral edge 36 juxtaposed to the peripheral walls 14 and the bottom surface 40 of the wells 32 being supported by the bottom wall 12 of the heat transfer tray 10, as shown in Figs. 6 and 7.

[0039] When the food tray 30 is inserted in the storage space 20 of the heat transfer tray 10, two longitudinally and two transversally extending gas and heat circulation channels 44 are defined between the peripheral walls 14 of the heat transfer tray 10 and the sidewalls 38 of the wells 32 since the sidewalls 38 are spaced-apart from the peripheral walls 14.

[0040] The longitudinally and transversally extending gas and heat circulation channels 44 intersect with one another at intersections 46 and are in fluid communication at the intersections 46 to define a gas and heat channel network, or ventilation network.

[0041] The gas and heat circulation channels 44 have ports in periphery of the food tray 30. The ports are substantially perpendicular to the top portion 34 of the food tray 30. [0042] Therefore, when heating the food heating assembly, gas and heat (hot air) can circulate freely between the wells 32 in the gas and heat circulation channels 44.

[0043] When the food tray 30 is inserted into the storage space 20 of the heat transfer tray

10, the bottom surface 40 of the wells 32 abuts the bottom wall 12 of the heat transfer tray 10. The lower surface of the top portion 34 consequently faces downwardly while the upper surface faces upwardly relatively to the heat transfer tray 10. The gas and heat circulation channels 44 extend substantially parallel to the bottom wall 12 of the heat transfer tray 10.

The food tray 30 therefore partitions the storage space 20 into a heating zone 48, between the bottom wall 12 and the food tray 30, and a food containing zone 50, above the food tray 30. When the wells 32 are filled with food, food remains in the food containing zone 50 and do not obstruct the gas and heat circulation channels 44 in the heating zone 48.

[0044] As mentioned above, the heat transfer pattern 18 of the heat transfer tray 10 is designed to control heat transfer in the heating zone 48, towards the food tray 30 and, more particularly, the wells 32. Thus, openings 16 are provided where heat transfer needs to be accelerated while the body 11 of the heat transfer tray 10 slows down heat transfer where needed. Heat can transfer directly by convection in the heating zone 48 of the storage space 20 when an opening 16 is provided. On the opposite, heat transfer occurs in the heating zone 48 through a combination of heat convection and conduction when a section of the heat transfer tray 10 is opening- free. Thus, the combination of sections including openings 16 and sections being opening- free in the heat transfer tray 10 defines the heat transfer pattern 18 and allows a better control of heat transfer in the heating zone 48 and towards the food tray 30. Thus, it is possible have an improved control over the food product heating.

[0045] For muffin baking, heat is generally supplied below the food tray 30 in a conventional oven. Thus, the bottom portion of the muffins, in the wells 32, is supplied with more heat and is generally more baked than the lateral or the upper portions of the muffins.

[0046] In the embodiment shown in reference to Figs. 6 and 7, the food tray 30 is inserted in the storage space 20 of the heat transfer tray 10. The heat transfer pattern 18 is designed to slow down heat transfer towards the bottom portion of the muffins and relatively accelerate the heat transfer towards the lateral portion.

[0047] Thus, the sections of the bottom wall 12 of the heat transfer tray 10 substantially in register with the bottom surface 40 of the wells 32 are opening-free to slow down heat transfer. Heat transfer towards the bottom surface 40 of the wells 32 occurs through a combination of heat conduction and heat convection, i.e. heat convection towards the heat transfer tray 10 and heat conduction in the heat transfer tray 10 and the food tray 30. Radiation also occurs. On the opposite, sections of the bottom wall 12 of the heat transfer tray 10 aligned with the gas and heat circulation channels 44 are provided with openings 16 to accelerate heat transfer towards the sidewalls 38 of the wells 32 and accelerate heating. Similarly, sections of the peripheral walls 14 of the heat transfer tray 10 aligned with the sidewalls 38 of the wells 32 are provided with openings 16 to accelerate heat transfer and consequently heating. In another embodiment, the peripheral walls 14 are configured to reduce gas movement or convection movement of hot air around the wells.

[0048] In the embodiment shown, the openings 16 defined in the bottom wall 12 are provided in sections aligned with the intersections 46 between the longitudinally and transversally extending gas and heat circulation channels 44. However, in an alternate embodiment, it is appreciated that openings can be provided anywhere in sections aligned with the gas and heat circulation channels 44.

[0049] Moreover, it is appreciated that the opening-free sections 52 such as or insulating sections under the bottom surface 40 do not necessarily have the same surface area than the bottom surface 40 and/or the same perfectly aligned periphery as shown in Fig. 6. In Fig. 6, two opening-free sections 52a have perfectly aligned periphery with the bottom surface 40a, one opening-free section 52b is smaller than the bottom surface 40b, and three opening-free sections 52c are wider than the bottom surface 40c. [0050] Warm gas (hot air) can enter in the heat transfer tray 10 through the openings 16 and flow through the gas and heat circulation channels 44 in the heating zone 48 of the heat transfer tray 10.

[0051] The openings 16 are sized to allow sufficient gasflow through the heating zone 48 of the heat transfer tray 10 to provide enhanced convective heat transfer, while also maintaining adequate structural strength and integrity of the heat transfer tray 10 for the insulating portions thereof to adequately support the cups during handling and baking.

[0052] The surface areas of the openings 16 vary in accordance with the desired heat transfer pattern 18. In the embodiment shown in reference to Figs. 6 and 7, the surface areas of the openings 16 vary between 250 and 2500 square millimeters. The size of the openings 16 can be adjusted in accordance with the customer's needs and the corresponding heat transfer tray 10.

[0053] The shape of the openings 16 can vary in accordance with the desired heat transfer pattern 18 as well as the mechanical properties of the resulting tray 10.

[0054] In an embodiment, the heat transfer tray 10 is made from heatable paperboard, using conventional manufacturing techniques. Other materials having appropriate strength characteristics over the entire temperature range of the heat transfer tray 10 (such as certain polymeric materials or metals) can also be used to fabricate the heat transfer tray 10.

[0055] In an embodiment especially suited for heating food products, the peripheral walls 14 have a length ranging between 5 to 40 centimeters and a height ranging between 2 to 20 centimeters. In an alternate embodiment, the peripheral walls 14 have a length ranging between 10 to 30 centimeters and a height ranging between 4 to 15 centimeters. The thickness of the heat transfer tray body 11 can range between 0.5 to 5 millimeters and, in an alternate embodiment, it can range between 1 and 3 millimeters. These dimensions are provided for illustrative purposes only, as various sizes of pans having different numbers of cups can be used and are commonly available. [0056] It is appreciated that the size, the shape, and the heat transfer pattern 18 of the heat transfer tray 10 is adapted to the size, the shape, and the design of the food tray 30 which is received in the storage space 20. For example and without being limitative, the shape of the food tray 30 can correspond substantially to the shape of the storage space 20 of the heat transfer tray 10 and the surface area defined by the periphery of the food tray 30 can be substantially equal to the surface area of the storage space 20 defined by the peripheral walls 14. In an alternate embodiment, the heat transfer tray 10 can be designed to receive more than one food tray 30 simultaneously in the storage space 20. Moreover, in an alternate embodiment, the food tray 30 can be relatively tightly received in the storage space 20 of the heat transfer tray 10 or slight displacement of the food tray 30 can be allowed in the storage space 20.

[0057] Similarly, the height of the heat transfer tray 10 can correspond substantially to the height of the food tray 30. In alternate embodiment, the height of the peripheral walls 14 of the heat transfer tray 10 can be higher or lower than the height of the food tray 30. The heat transfer tray 10 can be designed to receive more than one food tray 30 simultaneously in the storage space 20, one above the other.

[0058] It is appreciated that alternate embodiments can be foreseen to the embodiment described above in reference to Figs. 1 to 7. The shape and the design of the food tray 30 can vary and the shape and the design, more particularly, of the heat transfer pattern 18 of the corresponding heat transfer tray 10 will vary accordingly. For example and without being limitative, in an alternate embodiment (not shown), the food tray 30 can be a cake mould with only one central well 32. The corresponding heat transfer tray 10 can be opening- free in the bottom wall 12 to slow down the heat transfer towards the bottom surface 40 of the well 32 and each one of the peripheral walls 14 can be provided with at least one opening 16 to accelerate heat transfer towards the sidewalls 38 of the well 32.

[0059] In another alternate embodiment (not shown), the food tray 30 can be a frozen dinner tray with three wells 32 for containing different food products. The corresponding heat transfer tray 10 can include at least one opening 16 aligned with the bottom surface 40 of one well, the sections of the bottom wall 12 substantially in register with the bottom surfaces 40 of the other two wells 12 can be opening-free, and sections of the bottom wall 12 of the heat transfer tray 10 substantially in register with gas and heat circulation channels 44 extending between the wells can also be provided with openings 16. Similarly for the peripheral walls 14 of the heat transfer tray 10, openings 16 can be provided therein either aligned with the sidewalls 38 of the wells or aligned with the ports of the gas and heat circulation channels 44.

[0060] Thus, in a method for heating food products, which includes baking the food product, the food tray 30 is inserted in a heat transfer tray 10 having a heat transfer pattern 18 which corresponds to the design of the food tray 30 and to the properties of the food product which will be heated. The food product to be heated can be inserted in the wells 32 of the food tray 30 either before or after inserting the food tray 30 in the heat transfer tray 10. Then the food heating assembly, including the food tray 30, the heat transfer tray 10, and the food product, is transferred in an environment having a temperature T, which is higher than the temperature of the food product inserted in the food tray 30 and heat is transferred towards the food tray 30 and the food product through a controlled combination of conduction, radiation and convention. Heat transfer occurs in accordance with the heat transfer pattern 18 of the heat transfer tray 10.

[0061] In an embodiment, the assembly is placed either in a conventional oven, a convection oven or a micro-wave oven where the food product is heated. Heat transfer occurs between the assembly environment and the food tray 30 and the food product through a controlled mixture of convective and conductive heat transfer.

[0062] The food tray 30 can be made of various food adapted and heatable materials. For instance and without being limitative, it can be made of polymers such as polyethylene terephtalate (PET). It can also be made of steel, teflon, and the like.

[0063] As mentioned above, the combination of the heat transfer tray 10 and food tray 30 provides substantially improved control of heat transfer and consequently control of the food product heating. Thus, it is possible to adapt the heat transfer pattern 18 to substantially uniformly heat of the food contained in the food tray 30 or to obtain a temperature profile or heated profile in the food. For example, one might want to have a combination of tender and crispy sections in the heated food product.

[0064] The embodiments of the invention described above are intended to be exemplary only.

[0065] It is appreciated that the heat transfer tray 10 and food tray 30 can be sold together, as an assembly, or they can be sold separately. Moreover, the food product can be inserted in the food tray 30 when sold or the user can himself/herself prepare and insert the food in the food tray 30 before the heating step.

[0066] The food tray 30 and/or the heat transfer tray 10 can be adapted for storage and transportation of the food product. In an embodiment, the heat transfer tray 10 and the food tray 30 defining a food heating assembly which can include a lid or can be lid-free. The lid (not shown) can be sized and shaped to cover either the opening 22 of the heat transfer tray 10 or the food tray 30. The lid can be fully separable from the food heating assembly or it can be integral therewith or any other suitable alternatives. In an embodiment, the lid can include a polymer film applied over the top portion 34 of the food tray 30 and scelling the wells 32.

[0067] The heat transfer tray 10 can include a reinforcing web (not shown) extending in the storage space 20 and separating the latter in multiple subsections to increase the mechanical porperties of the tray 10.

[0068] It is appreciated that, in an alternate embodiment, the heat transfer tray can be inserted above the food tray 30 or that the food tray 30 can be inserted between two heat transfer tray, both have a similar or a different heat transfer pattern.

[0069] It is appreciated that, in an alternate embodiment, the food tray 30 can be only partially inserted in the heat transfer tray 10, i.e. a section of the food tray 30 can extend outwardly of the heat transfer tray 10. [0070] Even if in the embodiment described above in reference to Figs. 1 to 7 the heat transfer tray is rectangular in shape, it is appreciated that another shape of heat transfer tray 10 could be designed. For example the heat transfer tray could be round-shaped with a single panel defining the peripheral wall.

[0071] The scope is therefore indicated by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A food packaging system for baking frozen-dough food products from a frozen state, the food packaging system comprising:

a pan having a plurality of interspaced cups each having a bottom and a rim, and a pan panel extending around and interconnecting the rims of each cup; and a tray shaped for receiving the pan therein, the tray having a bottom panel with insulating sections each receiving a bottom of a corresponding cup when the pan is received, and at least one opening located between selected ones of the insulating sections, and walls extending upwardly around the bottom panel and engaging a periphery of the pan panel when the pan is received in the tray, the walls being configured to reduce convection movement of hot air around outer portions of the cups, adjacent the periphery of the pan, during baking, whereas the at least one opening is configured to relatively favor convection movement of the hot air around internal portions of the cups, away from the periphery of the pan.

2. The food packaging system of claim 1 wherein the plurality of cups comprise at least four equally interspaced cups, and the selected ones of the insulating sections correspond to the four equally interspaced cups.

3. The food packaging system of claim 1 wherein the walls are apertured to allow a controlled flow of convection air therethrough.

4. The food packaging system of claim 3 wherein, during baking, convection heat transfer with the outer portions of the cups resulting from the controlled flow of air through the apertured walls is comparable to convection heat transfer with the inner portions of the cups resulting from air movement across the at least one opening.

5. The food packaging system of claim 1 wherein the tray is made of a paper-based material.

6. The food packaging system of claim 1 wherein the pan is made of a plastic material.

7. The food packaging system of claim 1 further comprising frozen-dough food products in corresponding ones of the cups.

8. A food heating container comprising:

a heat transfer tray having wall panels with at least one heat transfer opening extending therethrough and at least one full section, the at least one opening and at least one opening-free section defining a heat transfer configuration, the wall panels defining a storage space in the heat transfer tray; and a food containing insert insertable in the storage space, having an upper face, an opposed lower face and at least one food containing well defined therein, the at least one heat transfer opening and the at least one opening-free section being respectively aligned with at least one section of the food containing insert for accelerating heat transfer and at least one section of the food containing insert for reducing heat transfer.

9. A food heating container as claimed in claim 8, wherein the food heating container is designed to slow down heat transfer towards the bottom surface of the at least one food well and relatively accelerate the heat transfer towards the lateral surface of the at least one well to provide a uniform heating in the well.

10. A food heating container as claimed in claim 8, wherein the at least one food well comprises: a bottom surface substantially in register with at least one of the at least one opening-free section for reducing heat transfer; and a lateral surface extending from the bottom wall of the at least one well.

11. A food heating container as claimed in claim 8, wherein the at least one food well has a cavity adapted to contain the food product to be heated.

12. A food heating container as claimed in claim 8, wherein the heat transfer pattern is designed to slow down heat transfer towards the bottom surface of the at least one food well and relatively accelerate the heat transfer towards the lateral surface of the at least one food well to provide a uniform cooking in the well.

13. A food heating container as claimed in claim 8, wherein the at least one food well comprises a frozen food.

14. A food heating container as claimed in claim 8, wherein the heatable transfer tray body comprises a bottom wall and peripheral walls extending upwardly from the bottom wall and the heat transfer pattern comprises at least one heat transfer opening extending through the bottom wall and at least one heat transfer opening extending through the peripheral walls.

15. A food heating container as claimed in claim 8, wherein the food well has a bottom surface substantially in register with at least one of the at least one opening- free section for reducing heat transfer.

16. A food heating container as claimed in claim 8, wherein the food tray comprises at least two food wells, the at least two food wells being spaced apart from one another and defining a gas channel in between, at least a section of the bottom wall of the transfer tray body substantially aligned with the gas channel having at least one of the at least one heat transfer opening defined therein.

17. A food heating container as claimed in claim 8, wherein the peripheral walls of the heat transfer tray comprises at least one heat transfer opening aligned with the at least one food well.

18. A heat transfer tray in combination with a heatable food tray, the heat transfer tray comprising: a heatable transfer tray body defining a storage space and having a heat transfer pattern including at least one heat transfer opening extending therethrough and at least one opening-free section; and the heatable food tray being at least partially insertable in the storage space and having a food tray body defining at least one food well with a food well outer surface, the at least one heat transfer opening and the at least one opening-free section being respectively aligned with predetermined sections of the food well outer surface for providing a controlled heat supply thereto.

19. A combination as claimed in claim 18, wherein the food heating container is designed to slow down heat transfer towards the bottom surface of the at least one food well and relatively accelerate the heat transfer towards the lateral surface of the at least one well to provide a uniform heating in the well.

20. A combination as claimed in claim 18, wherein the heatable transfer tray body comprises a bottom wall and peripheral walls extending upwardly from the bottom wall and the heat transfer pattern comprises at least one heat transfer opening extending through the bottom wall and at least one heat transfer opening extending through the peripheral walls.