A forced-air cooling / heating facility and associated cooling / heating method

Abstract

A forced-air heating / cooling facility for heating / cooling food products, the facility comprising: a heat transfer zone sized to receive a food product to be cooled or heated; an air heating / refrigeration zone adjacent the heat transfer zone; a heating or refrigeration means for heating or cooling air in the air heating / refrigeration zone; a partition separating the two zones; and air ducts extending out the partition into the heat transfer zone for distributing heated / cooled air from the air heating / refrigeration zone into the heat transfer zone, wherein the ducts comprise outlets configured to direct the heated / cooled air downwardly onto the food products to heat or cool the food product.

Description

[0001] A forced-air coolinq / heatinq facility and associated coolinq / heatinq method

[0002] Field of the invention

[0003] Disclosed herein is a forced-air cooling / heating facility. The facility is operable for cooling or heating food products. The facility has particular application in cooling produce stored in generally open containers. Also disclosed herein is a method of cooling or heating products using the presently disclosed facility.

[0004] Background

[0005] Food products are often required to be cooled or heating during packaging. It is often desirable to perform this cooling or heating process as quickly as possible to reduce process cost and processing time.

[0006] In some particular examples, certain consumable produce is cooled after harvest and before packing for transport, distribution, sale etc. For example, fruit such as grapes is often harvested and placed into open containers which may then be temporarily stored in a cooling facility so that the grapes can be cooled to a desired temperature prior to packing.

[0007] However, it is common to store grapes in containers such as boxes having a top that is open to the atmosphere but the remaining walls of the container are substantially impermeable to air and thus it is not possible to pull cold air through the containers. When such containers of grapes are cooled in known cooling facilities, the cooling of the grapes is not efficient nor evenly distributed, and this can compromise the overall shelf life and quality of the grapes. For example, it is common for grapes closer to the open upper end of containers to cool faster than grapes at or toward an opposite bottom end since the cold air in the cooling facility has a harder time travelling into the container. This results in a longer cooling time before each container of grapes has reached the desired temperature and it is known that extended cooling times can dry the grapes out; indeed the faster the grapes can be cooled, the better their condition.

[0008] It is known to cool numerous pallets of grapes at a time prior to packing.

[0009] However, current cooling facilities and methods are such that pallets, boxes, punnets etc. are not removed from the facilities until all pallets have reached the desired temperature. An associated disadvantage is that different pallets of grapes are cooled for different durations; for example, pallets that are cooled first are not removed until the last pallets of grapes have reached the desired temperature. In this way, different pallets of grapes are cooled for different durations, and often for longer than required, thereby compromising their quality and shelf life.

[0010] Although the process described herein relates to open containers of produce, in particular grapes, it will be appreciated that the embodiments described herein are also applicable to other food products such as packaged foods to be frozen, dairy goods such as yoghurt or cheese for example. Furthermore, although the system has been described in relation to cooling of a product, it may also be used for freezing or heating a product.

[0011] There is a need to address the above, and / or at least provide a useful alternative.

[0012] According to a first aspect of the present invention, there is provided a forced-air cooling facility for cooling open containers of produce, the facility comprising: a cooling zone sized to receive open containers of produce to be cooled; a refrigeration zone adjacent the cooling zone; a refrigeration means for cooling air in the refrigeration zone; a partition separating the two zones; and cooled air ducts extending out the partition into the cooling zone for distributing cooled air from the refrigeration zone into the cooling zone, wherein the ducts comprise outlets configured to direct the cooled air downwardly into the open containers to cool the produce therein.

[0013] In certain embodiments, the ducts are arranged in an array, each duct configured to extend over and supply cooled air into one or more of the open containers.

[0014] It is envisaged that the refrigeration means is disposed in the refrigeration zone and configured to discharge cooled air therein, the refrigeration zone being at a higher pressure than the cooling zone such that cooled air flows through the ducts to the cooling zone and returns to the refrigeration zone via through the refrigeration means.

[0015] In at least one embodiment, the cooling zone is sized to receive racks supporting two or more spaced apart rows of containers of produce to be cooled, wherein the ducts are arranged into groups for cooling produce of respective racks. In one example, the ducts are configured to extend into a space separating each row of spaced apart containers such that the ducts overlie at least one container.

[0016] In certain embodiments of the cooling facility, the refrigeration zone comprises a chamber for each group of ducts configured to regulate the airflow therethrough, each chamber having a fan for drawing cooled air from the refrigeration means into the chamber for supply through the ducts. For example, the speed of the fan of each chamber may be variable to adjust the airflow into each chamber and thus the associated group of ducts.

[0017] Embodiments of the cooling facility may further comprise a pressure release means for limiting the pressure within the refrigeration zone.

[0018] According to a second aspect of the present invention, there is provided a method of cooling produce stored in discrete open containers arranged in a grid on a rack, comprising: moving the rack of produce into the cooling zone of a forced-air cooling facility according to certain embodiments of the present cooling facility, the rack being arranged adjacent to the partition such that each container underlies a cooled air duct; and supplying cooled air through the ducts and into the open containers of produce, thereby cooling the produce to a desired temperature.

[0019] The method may further comprise removing the rack of cooled produce from the cooling zone of the facility for packing.

[0020] In certain examples, a plurality of racks is moved into the cooling zone for cooling of the produce thereon, wherein the method further comprising removing each rack individually from the cooling zone when the produce thereof has reached a desired temperature and / or after a predetermined period of time.

[0021] Brief description of the drawinas

[0022] An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0023] Fig. 1A is a side view of a rack of open containers containing produce to be cooled;

[0024] Fig. IB is an end view of the rack of Fig. 1A;

[0025] Fig. 2A is a side view of the rack of Fig. 1A arranged for cooling within a forced-air cooling facility according to embodiments of the present invention;

[0026] Fig. 2B is an end view of the rack of Fig. 2A arranged in the cooling facility;

[0027] Fig. 3 is a schematic top view of a forced-air cooling facility according to one embodiment of the present invention;

[0028] Fig. 4 is a perspective view of an array of ducts of the facility of Fig. 3;

[0029] Fig. 5 is a perspective view of the array of ducts of Fig. 4 with a rack of produce inserted therein;

[0030] Fig. 6 is a schematic top view of a forced-air cooling facility according to another embodiment of the present invention; Fig. 7 is a perspective view of an array of ducts of the facility of Fig. 6;

[0031] Fig. 8 is a close view of the array of Fig. 7, with a produce container inserted;

[0032] Fig. 9 is a schematic side view of a chamber associated with a group of cooled air ducts of a cooling facility according to embodiments of the present invention;

[0033] Fig. 10 is a schematic perspective view of racks of produce arranged for cooling by embodiments of the present cooling facility;

[0034] Fig. 11 is a perspective view of air supply ducts and an actuator for opening containers of produce;

[0035] Fig. 12 is a perspective view of ends of ducts 12 showing a rotation mechanism;

[0036] Fig. 13 is a duct mounting configuration to accommodate different sized products;

[0037] Fig. 14 is another duct mounting configuration to accommodate different sized products;

[0038] Fig. 15 is a further duct mounting configuration to accommodate different sized products;

[0039] Fig. 16 is an end view of a propulsion system for rotating a duct;

[0040] Fig. 17 is a cross sectional view of the propulsion system; and

[0041] Fig. 18 is perspective view of an array of ducts with means for controlling airflow through the ducts.

[0042] Detailed description

[0043] A forced-air heating / cooling facility 6, 106 according to preferred embodiments of the present invention are shown in Figures 3 and 4. The facility is configured for heating / cooling food products and comprises: a heat transfer zone 14 sized to receive a product to be cooled or heated; an air heating / refrigeration zone 16 adjacent the heat transfer zone 14; a heating or refrigeration means 18 for heating or cooling air in the air heating / refrigeration zone 16; a partition 20 separating the two zones; and air ducts 12 extending out the partition 20 into the heat transfer zone 14 for distributing heated / cooled air from the air heating / refrigeration zone 16 into the heat transfer zone 14, wherein the ducts 12 comprise outlets configured to direct the heated / cooled air downwardly onto the food products to heat or cool the product.

[0044] Figures 1 to 3 illustrate an embodiment where the facility 6 is configured for cooling produce, the produce being boxes of produce.

[0045] Figs. 1A and IB show an example of a rack 2 upon which open containers or boxes of produce 4 to be cooled can be arranged before placement in a cooling facility 6 according to embodiments of the present invention. The rack 2 is wheelable via groundengaging castors 8 which support frame members 10 upon which containers of produce 4 can be arranged in one or more grids containing rows and columns. In the depicted embodiment, the rack 2 is shown carrying two grids of containers 4, each grid having four rows and five columns, making for a total of 40 containers 4. Of course, the rack 2 may take any suitable form for carrying any number of desired containers 4.

[0046] Importantly, the rack 2 is configured such that each row of containers 4 is vertically spaced from an adjacent row of containers 4. In other words, the containers 4 are not directly stacked upon one another; instead, there exists a space 11 above each container 4 and it is via this overlying space 11 via which cooled air from the present cooling facility 6 can be supplied into the open containers 4. This is shown in Figs. 2A and 2B; as will be discussed, the present cooling facility 6 comprises groups of cooled air ducts 12 under which open containers 4 can be arranged for cooling thereof. The ducts 12 are generally hollow tubes, preferably formed of stainless steel, which distribute air over containers 4. The ducts 12 are formed with a plurality of air apertures or outlets in the form of holes through which cool air flows. The apertures may be in a lower surface of the duct, or may be formed around the circumference of the duct 12 so that air can be distributed in different directions to contact not only the product under the duct 12, but sides and a bottom surface of the container 4. It will be appreciated that the number, location and size of apertures / outlets will vary according to the product to be cooled and the flow rate and temperature of air flowing through the duct. Fig. 3 is a schematic diagram of an example cooling facility 6 according to an embodiment of the present invention. In particular, there is disclosed a generally enclosed and forced-air cooling facility 6 configured to cool open containers of produce 4, such as grapes. The cooling facility 6 comprises a cooling zone 14 sized to receive the open containers of produce 4 to be cooled; in the present embodiment, the depicted facility 6 is sized to receive a plurality of racks 2 of open containers of grapes, such as the rack 2 shown in Figs. 1A to 2B. For example, it is envisaged that once the produce has been harvested and placed into the open containers 4 and loaded onto the racks 2, the racks 2 can simply be wheeled into the cooling zone 14 of the cooling facility 6 where the racks 2 of produce can then be cooled to the desired temperature and / or for a predetermined period.

[0047] The present cooling facility 6 also comprises a refrigeration zone 16 where cool air is generated and supplied to the cooling zone 14. For example, the refrigeration zone 16 may house a refrigeration means 18, such as one or more known refrigeration units, for discharging cooled air in the refrigeration zone 16. The refrigeration zone 16 is adjacent to the cooling zone 14 and is substantially separated therefrom by a partition 20 such as a wall. The cooling facility 6 also comprises a plurality of cooled air ducts 12 which extend out the partition 20 into the cooling zone 14, the ducts 12 being configured for distributing cooled air from the refrigeration zone 16 into the cooling zone 14.

[0048] Preferably, the refrigeration zone 16 is maintained at a higher pressure than the cooling zone 14. In this way, cooled air from the refrigeration zone flows through the ducts 12 and into the cooling zone 14 to cool the stored produce. After cooling, air from the lower pressure cooling zone 14 flows back to the higher pressure refrigeration zone 16 via the refrigeration means 18.

[0049] Figures 6 to 8 illustrate another cooling facility 106 which is automated. In this regard, conveyors 50 are provided to transport the containers of produce 4 under a plurality of fixed ducts 12. Conveyors 50 may include a single conveyor passing under a row of ducts 12, or multiple conveyors may be provided, each passing under a row of fixed ducts 12. The conveyors 50 convey the food product through the facility to automate the process of cooling. Conveyor 50 may be a belt conveyor or a series of rollers. The belt may be webbed so that air can move through the belt, particularly when the duct 12 is applying air upwardly onto a food product above the duct 12.

[0050] Cooling facility 106 is similarly configured to facility 6, in that it includes a cooling zone 14 and a refrigeration zone 16 where cool air is generated and supplied to the cooling zone 14. Refrigeration means 18 are provided which may be in the form of a high humidity air handler. Where facility 106 differs from facility 6 is that the refrigeration means is external of the facility and may be elevated. The cooled air is thus supplied to the refrigeration zone 16 view overhead ducts 52. Separation wall 15 may be provided to split the refrigeration zone 16 into different parts. As per facility 6, cooled air from the refrigeration zone 16, passes through ducts 12 and into the cooling zone 14. Warmer air within the cooling zone 14 is drawn upwardly into the refrigeration means 18, cooled and then transported via duct 52 to the refrigeration zone 16, where is falls and can pass back into the ducts 12.

[0051] It will be appreciated that the different features from facility 6 and facility 106 may be interchangeable.

[0052] It is envisaged that the ducts 12 may be tubular or otherwise in the form of pipes and the like which extend transversely through the partition 20 and into the cooling zone 14, each duct 12 being arranged to extend above at least one container of produce 4. Referring to Figs. 2A and 2B, the present cooling facility 6 may have groups of ducts 12 wherein the ducts 12 of each group are arranged in a grid or array such that they extend over all the containers of produce 4 on a rack 2. Such an array is illustrated in Figures 4 and 5. In the embodiment shown in Figs. 2A and 2B, each group comprises 20 ducts 12 arranged in a grid of four rows and five columns, each duct extending over two grids of containers 4 such that all 40 containers can be cooled by the 20 ducts 12. Of course, any suitable arrangement and number of ducts 12 may be provided to suit the arrangement of containers 4 on the racks 2. Alternatively, the positioning and arrangement of containers 4 and / or racks may be arranged to suit the positioning of the ducts 12.

[0053] While not shown, each duct 12 is configured to supply cooled air downwardly into the underlying containers 4. For example, the ducts 12 may have downwardly directed outlets, openings or nozzles configured to distribute cooled air downwardly and directly into the open containers 4 via the open tops thereof, thereby more directly cooling the produce within each container 4 such that the produce can be cooled more rapidly and evenly. Since the walls of the containers 4 are substantially closed, the cooled air simply enters the container 4, cools the produce, and exits out the container 4 through the open top thereof ready to be cycled back to the refrigeration zone 16 via the refrigeration means 18.

[0054] During operation of the present cooling facility 6, it may be that the air pressure within the refrigeration zone 16 decreases with increased distance away from the refrigeration means 18, in which case ducts 12 closer to the refrigeration means 18 may receive a greater volume of cooled air than ducts 12 distal from the refrigeration means 18; this may result in certain racks 2 closer to the refrigeration means 18 to be cooled faster than racks further from the refrigeration means 18. To limit or prevent this potential uneven distribution of cooled air, the present cooling facility 6 may be provided with means for controlling the amount of cooled air each group of ducts 12 receives.

[0055] To this end, Fig. 9 shows a schematic view of a chamber arrangement 22 that may be incorporated into cooling facilities 6 according to embodiments of the present invention, each chamber 22 functioning to control the airflow of cooled air from the refrigeration zone 16 through a respective group of ducts 12. Each chamber 22 may be provided with an opening for receiving cooled air discharged from the refrigeration means 18, wherein a variable speed fan 24 is provided to control the flow of cooled air into the chamber 22 and thus the ducts 12 enclosed at the refrigeration zone 16 by that chamber 22. For example, chambers 22 further away from the refrigeration means 18 may be configured to have faster fan speeds to promote airflow into those chambers 22 as compared with chambers 22 closer to the refrigeration means 18. In this way, the chambers 22 help to regulate the airflow through the respective groups of ducts 12, thereby promoting a more even distribution of cooled air across all the ducts 12. While not shown, it is also envisaged that the refrigeration zone 16 may be provided with a pressure release means, such as a hinged flap, for releasing air from the refrigeration zone 16 if it is detected that the pressure therein exceeds a certain maximum threshold. A control mechanism may be provided for each chamber 22 and regulated by pressure sensors or such, to control pressure via fan speed operation.

[0056] Fig. 10 is a schematic view showing the partition 20 of the cooling facility 6, provided with outwardly extending guideposts 26 to help with the positioning of racks 2 in the cooling zone 14 and against the partition 20 so that the open containers 4 can be arranged beneath the ducts 12 for cooling. In use, each rack 2 can be individually wheeled into the cooling zone 14 of the cooling facility 6 and cooled for a desired period and / or to a desired temperature. Similarly, each rack 2 can be individually removed from the cooling facility 6 once the desired temperature / time is reached such that the produce is not cooled for longer than is necessary, thereby preserving the quality of the produce.

[0057] Figure 11 illustrates an actuator 54 which may be provided to open each container 4 as it passes along conveyor 50 and to ensure that the container remains in an open position under air pressure when disposed under duct 12 to ensure contact between the produce and the air stream exiting the duct 12. Actuator 54 is in the form of a removable bar or rod extending out into the cooling zone 16, though it will be appreciated that the actuator may take other forms, such as a hook, arm etc. The diameter of the rod 54 may vary as required and it may be that cross-sectional shapes other than circular are used.

[0058] Figure 12 illustrates an improvement to duct 12 whereby the duct is configured for rotational reciprocation so that air flowing from the duct 12 can be evenly distributed over the product to be cooled. To achieve this, ducts 12 are rotationally mounted within the wall 20 of the cooling facility and a linkage 56 is provided which couples the ducts 12 together on an upper surface. Linkage 56 is driven by motor 58 which reciprocates, thereby rotating the ducts 12 between an angle of plus / minus 45 degrees. The speed of reciprocation will vary according to the product to be cooled and the flow rate and temperature of air flowing through the duct.

[0059] It will be appreciated that rotation of the ducts may be driven by different means, such as chains, belts or gears, or individual motor drives may be provided for each duct.

[0060] It will be appreciated that it will be desirable for facility 6 or 106 to be able to accommodate different products and therefore it would be advantageous if the spacing between ducts 12 could vary. Figures 13 to 15 illustrate different methods for achieving this. Although the figures show a single column of ducts being moved, multiple columns of ducts or rows of ducts may also be grouped.

[0061] In the embodiment of Figure 13, this is achieved by moveable plate 60 that is mounted in wall 20 of facility 6 or 106, and slidable in a vertical direction. Ducts 12 are mounted in plate 60 and their position can be varied by moving the plate 60. Plate 60 is formed with multiple apertures, some of which ducts 12 extend through, and others are covered by blanks 62. To allow the facility 6 or 106 to be used with products of different sizes, ducts 12 may be moved to different positions.

[0062] It will be appreciated that as plate 60 slides, a space is created above and below the plate 60 and through which cooled air can pass from the refrigeration zone 16 to the cooling zone 14. To prevent this occurring, a seal will be provided, such as the concertina baffle 64 shown above and below the plate 60 in Figure 14.

[0063] Figure 15 illustrates a further embodiment where multiple plates 60 are provided, each plate being vertically slidable to vary the position of duct 12 to accommodate different sized products. Each plate 60 may be independently slidable or the plates may be coupled together somehow. In this embodiment, between each plate there is a concertina baffle 64 above and below to prevent leakage of air from the refrigeration zone 16 to the cooling zone 14. Movement of the plates 60 may be automatically controlled or adjusted manually. Location holes may be provided to allow for pre-set positioning of the plates 60. It will be appreciated that the baffle 64 may take other forms.

[0064] Figures 16 and 17 illustrate the specific construction of a propulsion system 112 for an air supply duct 12. Propulsion system 112 includes housing 72 which mounts around duct 12. Housing 72 may be formed in two parts, one either side of partition 20. Bearings 70 are provided to support duct 12 and facilitate rotation. Rotation may be performed with any conventional means such as a motor or mechanism, though in the illustrated embodiment, pairs of permanent magnets 74 are provided on the duct 12 and positioned relative to energized magnets 76 on the housing 72. Magnets 76 are energised via wires 78. Although pairs of magnets are shown, any number of magnets may be used. As air flows through duct 12, rotation of the duct 12 changes direction of the air flow. Duct may continuously rotate or reciprocate in alternating directions. The speed and direction of the rotation is varied by control of magnets 76.

[0065] It can be desirable to vary the amount of air flowing through each duct 12 and this may be achieved by different means. One example is shown in Figure 13 where duct 12 is formed with a plurality of air outlets 80. Blanking plates 82 are provided to close outlets 80, either completely or partially. The blanking plates 82 are connected via arm 84, which is slidable to open and close the outlets 80. Fig. 17d shows the outlets completely closed, Fig 17c shows them partially open, Fig 17b shows them partially closed and Fig 17a shows the outlets 80 completely open. Such a mechanism may be provided to selectively control the air flow from different ducts 12. The blanking plates 82 are shown as moving in a longitudinal direction, though in other embodiments they may move transverse to a longitudinal axis of the duct or simply pivot upwardly.

[0066] Many modifications of the above embodiments will be apparent to those skilled in the art without departing from the scope of the present invention. For example, the cooling facility can have any desired cooling capacity, size, ducts, duct arrangements, refrigeration units etc. In Fig. 3, the depicted facility 6 comprises two cooling zones 14, each with a corresponding refrigeration zone 16, partition 20 and refrigeration unit 18. While the cooling facility 6 has been described in the context of cooling produce, it is of course possible that the facility 6 may be operable to cool other types of products such as packaged foods to be frozen like lasagne or other pre-made meals, dairy goods such as yoghurt or cheese for example. These products may be in open or closed packaging.

[0067] Furthermore, although the system has been described in relation to cooling of a product, it may also be used for freezing or heating a product. In such an embodiment, instead of a refrigeration unit 18, a heating unit would be provided.

[0068] The described embodiments can offer a number of advantages, particularly relating to speed and efficiency in cooling / heating, thereby resulting in a reduction in cooling time which may allow for produce to be picked, cooled, packed and sent on the same day, thereby reducing processing time and energy costs. With previous cooling processes, for example with cooling table grapes, the cooling process can take 12-14 hours, meaning that the process will need to run overnight and using mains power during peak periods. With the presently described embodiments and the reduced energy consumption, the process can run during daylight hours so solar power can now be used, further reducing process costs and increasing quality of the cooled product.

[0069] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

[0070] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

Claims

CLAIMS:

1. A forced-air heating / cooling facility for heating / cooling food products, the facility comprising: a heat transfer zone sized to receive a food product to be cooled or heated; an air heating / refrigeration zone adjacent the heat transfer zone; a heating or refrigeration means for heating or cooling air in the air heating / refrigeration zone; a partition separating the two zones; and air ducts extending out the partition into the heat transfer zone for distributing heated / cooled air from the air heating / refrigeration zone into the heat transfer zone, wherein the ducts comprise outlets configured to direct the heated / cooled air downwardly onto the food products to heat or cool the food product.

2. The facility of claim 1, wherein the ducts are arranged in an array, each duct configured to extend over and supply heated / cooled air over the food products.

3. The facility of claim 2, wherein a vertical height of the ducts can be varied to accommodate food products of different sizes.

4. The facility of any preceding claim, wherein the ducts are configured to rotate to evenly distribute air over the food product to be heated / cooled.

5. The facility of any preceding claim, wherein the outlets are longitudinally spaced along the duct and formed around a circumference of the duct.

6. The facility of any preceding claim, wherein the heating / refrigeration means is disposed in the heating / refrigeration zone and configured to discharge heated / cooled air therein, the heating / refrigeration zone being at a higher pressure than the heat transfer zone such that heated / cooled air flows through the ducts to the heat transfer zone and returns to the heating / refrigeration zone via through the heating / refrigeration means.

7. The facility of any preceding claim, further comprising at least one conveyor belt extending underneath the air ducts, the conveyor belt for conveying the food product through the heat transfer zone for heating / cooling the food products.

8. The facility of claim 7, further comprising an actuator for engaging packaging of a food product to open the packaging as it passes underneath the duct and hold it in an open position.

9. The facility of any one of claims 1 to 6, wherein the heat transfer zone is sized to receive racks supporting two or more spaced apart rows of food products to be cooled, wherein the ducts are arranged into groups for heating / cooling the respective food products.

10. The facility of claim 9, wherein the ducts are configured to extend into a space separating each row of spaced apart food products such that the ducts overlie at least one food product.

11. The facility of any preceding claim, wherein the food products are open containers of produce and the heated / cooled air heats or cools the food product in the open container.

12. The facility of any preceding claim, wherein the heating / refrigeration zone comprises a chamber in communication with the inlets of a group of ducts, the chamber configured to regulate the airflow through the group of ducts, each chamber having a fan for drawing air from the heating / refrigeration means into the chamber for supply to the heat transfer zone.

13. The facility of claim 12, wherein the speed of the fan of each chamber is variable to adjust the airflow into each chamber and thus the associated group of ducts.

14. The facility of any one of the preceding claims, further comprising a pressure release means for limiting the pressure within the refrigeration zone.

15. A method of heating or cooling food products, comprising: moving the food products through the heat transfer zone of a forced-air cooling facility according to any one of the preceding claims, the food products being arranged to pass by an air duct; and supplying heated or cooled air through the ducts and over the food products, thereby heating or cooling the products to a desired temperature.

16. The method of claim 15, wherein the food products are moved through the heat transfer zone via a conveyor belt with the food products passing under the ducts.

17. The method of claim 15, wherein the food products are produce stored in discrete open containers arranged in a grid on a rack.

18. The method of claim 17, further comprising removing the rack of cooled produce from the heat transfer zone of the facility for packing.

19. The method of claim 17 or 18, wherein a plurality of racks is moved into the heat transfer zone for heating / cooling of the produce thereon, the method further comprising removing each rack individually from the heat transfer zone when the produce thereof has reached a desired temperature and / or after a predetermined period of time.

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