Food Processing Apparatus and Method

The present invention relates generally to the processing of foods. More particularly it relates to apparatus, a system and a method for cooling or freezing food.

Although applicable to a wide range of other foods, the present invention will be described hereinafter with particular reference to its application for the processing of meat. It will be understood, however, that this description is provided without prejudice to the generality of the invention or its range of applications.

Hitherto, there have been various methods and apparatus employed in the processing of meat, particularly methods and apparatus associated with the cooling of meat after it has been cooked. The rate at which heat can be removed from the surface of a material, such as meat, depends on a number of factors which include the temperature differential between the surface and the cooling medium, the natural conductivity of heat by the cooling medium (usually related to its moisture content), and the flow, rate of the cooling medium over the surface of the material. It is desirable for a cooling system to perform at an effective rate and evenly over a batch of product.

The most common method for cooling meat in this manner is to place the meat on a floor-mounted rack, such as a wheeled trolley or pallet, and deposit the rack at

the base of a chamber which cools the meat by means of a blast cooler. The blast cooler propels chilled air onto the surface of the meat.

Alternatively, the meat may be cooled by means of a liquid coolant, which is a good natural conductor of heat. The use of liquids necessitates the inclusion of collection facilities in the processing apparatus. It is known to provide cooling chambers with a collection tray to collect liquid coolant after it has been showered over the meat. The tray presents an obstructed threshold to the cooling chamber which prevents the use of ground-engaging meat racks. Furthermore, the tray will fill with coolant and potentially submerge meat if not raised from the ground, hi this type of arrangement, it is therefore necessary to place the meat on a rail- mounted rack, that is a rack which may be suspended beneath an elevated rail in order to allow it to be carried over the threshold into the chamber and be held suspended over the tray. It will be understood that the term 'tray' includes features such as a bath, sump or the like. An increasing number of products are being packaged in film for processing and sale, which film can protect the meat from the cooling medium.

The disadvantages associated with the use of a blast cooler when compared to the use of a liquid coolant arrangement include the significantly higher energy costs for operating a blast cooler system. The energy costs relate to the energy required to operate and cool the blast cooler fans, which is often one third of the total energy required by the blast cooler system, the energy required by the compressors (which are known to frequently operate inefficiently) and the loss of energy due to

the fact that energy cannot be stored in the same manner as from a liquid in a cold sink. Further, the propelled gas, such as air, within a blast cooler system is constantly losing velocity before it reaches the surface of the meat to be cooled, and it is for this reason that air cooling produces more variable results than liquid cooling. Furthermore, the blast cooling system also suffers from the disadvantage of being unable to extract heat rapidly enough from large pieces of meat in order to meet the industry codes of practice. The ability of cold air to carry moisture is low making it a naturally poor conductor of heat. As a result, high flow rates are required to compensate for this deficiency in order to attain adequate cooling which generally increases the operating costs. Blast cooler systems, and other systems of a similar nature, also present problems with regard to their cleaning and maintenance due to their generally being a number of components enclosed within a casing associated with such systems.

Conversely, whilst a liquid coolant arrangement may evade the above-identified deficiencies associated with blast cooling, a liquid cooling arrangement is, however, bestowed with its own limitations. The principle limitation of known liquid coolant arrangements lies in the fact that the chamber, having a liquid collection bath at the base thereof, presents a threshold at the chamber entrance, thereby obstructing access to floor-mounted racks. The need to systematise a chamber so that it can accommodate a rail-mounted rack is both costly and produces an inflexible system. The rails must be pre-set in terms of location within a manufacturing site, such as a factory, which can increase the handling costs. A chamber of this type can, therefore, require considerable headroom to

accommodate the rail-mounted rack. By contrast, the use of floor-mounted racks within blast cooling systems is advantageous in that it offers more flexibility in the range of movement that the meat may take about the manufacturing site. In other words, the location and movement of meat is not restricted by fixed rails.

hi another liquid coolant-based system, the meat is conveyed, fully immersed, through a tank of brine. This is disadvantageous for reasons relating to contamination of the food and the expense of such equipment and its tendency to consume large amounts of space.

A known liquid coolant-based system is depicted in Figure 1. Figure 1 shows a perspective view of a food processing apparatus, generally indicated 101, and a food support structure, generally indicated 103.

The food processing apparatus 101 comprises a food processing chamber 105, a liquid coolant bath 107 and a showering device 109. The food processing chamber 105 is in the form of a parallelepiped cabinet with the liquid coolant bath 107 at its base. The bath 107 is generally tray-like and comprises a base 107a, a front wall 107b, a rear wall 107c and two opposing side walls 107d, 107e. The depth of the liquid coolant bath 107 is in the region of a quarter of the height of the food processing chamber 105. The depth of the liquid coolant bath can, of course, vary and may range from 200mm to 300mm, for example. The showering device 109 is positioned centrally beneath the ceiling of the food processing chamber 105.

The food support structure 103 is a rail-mounted rack which has a corresponding shape to, but smaller dimensions than, the food processing chamber 105, so that it may fit inside the food processing chamber 105 during use. The food support structure 103 has three spaced shelves 113, each supporting food 111 to be processed, in this case slabs of meat. The roof of the food support structure 103 includes a pair of carriages 104 by which it is mounted on an elevated linear rail 115 leading to the interior of the food processing chamber 105.

During use, the food support structure 103, supporting food 111 thereon, is mechanically pushed along the rail 115 into the food support chamber 105. The food 111 is then showered or deluged with liquid coolant dispensed from the showering device 109 in order to accelerate the cooling of the food 111. Liquid coolant, after passing through the food support structure 103 absorbing heat from the food 111 as it goes, is collected in the liquid coolant bath 107, from where it is either discarded or recirculated. Due to the presence of the liquid coolant bath 107 within the food processing apparatus 101, it is not possible to utilise a floor- mounted rack as this could cause contamination of the liquid coolant from contact with its bottom surface. It is, therefore, necessary to suspend the food support structure 103 above the liquid coolant bath 107 by means of the rail 115, so that the structure 103 can be carried over the front wall 107b of the bath 107 and so that the food 111 at the bottom of the rack does not become submerged within liquid coolant in the bath 107, which could lead to contamination of the food 111.

From the discussion that is to follow it will become apparent that the present invention addresses the deficiencies associated with the prior art, whilst providing numerous additional advantages not hitherto contemplated or possible with prior art constructions.

According to a first aspect of the present invention there is provided food processing apparatus comprising a chamber for receiving food supported on a food support structure, and having means for supplying liquid coolant to the interior of the chamber, wherein the apparatus has an at least partially unobstructed base which is adapted to receive and support a ground-engaging food support structure.

The present invention therefore addresses the long-standing problem associated with the prior art, in that the present invention makes it possible to employ the use of a floor-mounted rack for supporting the food to be cooled or frozen within a liquid coolant-based system. This circumvents the necessity to employ the use of rail-mounted racks, thereby adding to the flexibility and lowering the handling costs of the present invention. The use of a liquid coolant also offers the benefit of conserving the energy within the system, that is by acting as a cold sink, and providing more consistent pooling results. In addition, a liquid coolant is much more effective in extracting heat from large pieces of meat, thereby helping to ensure that industry codes of practice and regulations are met. The invention enables food to be cooled or frozen rapidly and evenly.

The chamber may have a passageway along its partially unobstructed base for foot and wheeled traffic, for example.

The food processing apparatus may further comprise a sump for collecting liquid coolant, particularly coolant that has already passed over or through the food, which would otherwise fall to the base of the chamber. The sump may be located at or towards the base of the processing chamber, and may comprise two or more spaced collection vessels. Additionally or alternatively, the sump may comprise one or more channels; the channels may be elongate.

The apparatus may further comprise drainage means for draining liquid coolant from the chamber. Preferably, the drainage means will be located at the base of the chamber where the liquid coolant is likely to accumulate. The drainage means may take the form of an aperture in the base, for example, from which the used liquid coolant may be conveyed to an alternative location for storage and/or recirculation. It is, of course, possible that the apparatus does not comprise any drainage means, and that the chamber is provided with enough storage space therein to be able to store and recirculate the liquid coolant, much like a self- contained or closed system.

In some arrangements, the means for supplying liquid coolant may comprise a bulk liquid coolant storage tank, which tank may or may not be located externally of the chamber. A bulk liquid coolant storage tank is particularly beneficial where a surplus amount of liquid coolant is present within the system and needs to be

relocated away from the processing chamber. This is particularly the case if the liquid coolant within the bulk storage tank is to be used as a means for adjusting the temperature of the liquid coolant to be supplied to the chamber. For example, the used liquid coolant within the chamber may be recirculated, by a pump or the like, back to the means for supplying liquid coolant via the bulk liquid coolant storage tank, within which tank the temperature of the liquid coolant differs from the temperature of the liquid coolant present within the chamber.

The apparatus may comprise a reservoir or supplementary tank for storing coolant prior to use. The reservoir may comprise a 'header' tank for supplying the chamber with liquid coolant.

In embodiments, the means for collecting or redirecting the liquid coolant may be integrally formed with the food support structure, more specifically with the base of the food support structure, for example.

The supplementary tank may communicate directly with the bulk tank for the regulation of liquid coolant. The liquid coolant within multiple supplementary tanks of multiple chambers may be regulated and served by a parent bulk tank, for example.

The apparatus may further comprise means for adjustment of at least one parameter selected from the group comprising of: the temperature of liquid coolant in the chamber; the temperature of liquid coolant in the bulk liquid coolant storage

tank; the concentration of liquid coolant in the chamber; the concentration of liquid coolant in the bulk liquid coolant storage tank; and the flow rate of liquid coolant.

The concentration of the liquid coolant, referenced above, may relate to the concentration of salt within the liquid coolant, where the liquid coolant is brine for example. It may be desirable that the flow rate of the liquid coolant be adjustable so that heat transfer within the chamber may be controlled. In this way, the functions of the apparatus may be controlled by a controller, which may be programmable with pre-set values. In a similar manner, the apparatus may be provided with monitoring means to monitor parameters such as temperature, pressure, flow rate and concentration of liquid coolant, or the atmospheric temperature of the chamber, for example.

The apparatus may further comprise means for cooking food. This is particularly the case where the food, such as meat, is to be cooked before cooling. It is, of course, possible that the food to be cooled is raw meat, which does not require cooking before cooling in those circumstances. The possibility of cooking the food within the chamber, which also cools the food, is advantageous in that the food does not have to be transferred between a cooking and cooling region, which is efficient both in terms of time and space. In the case of chilled foods containing meat as a constituent, it is important for microbiological safety reasons and for sensory quality reasons, that cooling of the meat is carried out as rapidly as possible after cooking, and the present invention, therefore, lends itself to an arrangement which supports this reasoning.

The chamber of the apparatus may have an unobstructed threshold, and as a consequence it may be possible to enter or cross the threshold unimpeded whilst operating a floor mounted rack, supporting food thereon, for example.

In a second aspect of the present invention there is provided a method of processing food, comprising the steps of: providing a processing chamber having an at least partially unobstructed threshold and means for supplying liquid coolant to its interior; manoeuvring a floor-mounted food support structure over the threshold; - depositing the structure in the chamber; cooling food supported by the structure; and removing the structure from the chamber.

The method of the present invention may further comprise the step of cooking the food within the chamber before supplying liquid coolant thereto.

The liquid coolant may be caused to percolate through to the food pieces during cooling thereof, thereby maximising the surface area of the food which may potentially come into contact with the liquid coolant.

The liquid coolant may be supplied to the chamber through a showering device. The showering device may, for example, be located on the roof or ceiling of the chamber so that, during use, the liquid coolant is dispensed and falls onto the food under gravity.

In a third aspect of the present invention there is provided a food support structure for use in processing food involving cooling using liquid coolant, comprising a ground-engaging body capable of supporting food, and liquid coolant diverting means which, in use, divert liquid coolant into a collection vessel.

The food support structure may further comprise liquid coolant collection means, such as a sump or collection tray for example, so that the liquid coolant may be recirculated to either a showering device or bulk tank, for instance, directly therefrom.

Because the structure is floor-mounted, it can be provided with wheels or the like which allow it to be moved but also raise its base off the ground so that the food does not become submerged in use.

The food support structure may further comprise wheel or other ground support means to allow it to rest on the base, for example, of a liquid coolant-based food processing chamber.

The body of the food support structure may comprise at least one shelf for the placement of food. Utilising a multiple shelf structure may facilitate the staggering of food between adjacent shelves so that liquid coolant may percolate through the food more readily during use.

^■ The present invention envisages a food processing system comprising apparatus as described hereinbefore in combination with a food support structure as described hereinbefore.

The chamber and food support structure of the food processing system, detailed above, encompass all the advantages and features of the chamber, of the food processing apparatus, and food support structure, detailed in relation to the first and third aspects of the present invention.

The food support structure of the food processing system may be deposited in and withdrawn from the chamber.

The food processing system may further comprise diverting means for diverting used liquid coolant from the food support structure to the sump. Liquid coolant diversion may be necessary to circumvent food from becoming submerged within used liquid coolant.

The food processing system of the present invention may further comprise a pump capable of recirculating used liquid coolant back to the means for supplying liquid coolant. The used liquid coolant may, for example, be located in the sump or in the bulk liquid coolant storage tank, which tank may or may not be located externally of the chamber.

Various embodiments of the present invention will now be more particularly described by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a known food cooling system; Figure 2 is a perspective view of a food support structure formed according to an aspect of the present invention;

Figure 3 is a cross sectional view of the food support structure of Figure 2;

Figure 4 is a perspective view of a food support structure formed according to an alternative embodiment of the present invention; Figure 5 is a cross sectional view of a food support structure with liquid coolant diverting means formed according to an alternative embodiment of the present invention;

Figure 6 is a cross sectional view of a food support structure illustrating a staggered conformation of food placed thereon; Figure 7 is a perspective view of food processing apparatus formed according to an aspect of the present invention;

Figure 8 is a cross sectional view of the food processing apparatus of Figure 7;

Figure 9 is a cross sectional view of the food processing apparatus as shown in Figure 8 further comprising a food support structure deposited therein;

Figure 10 is a perspective view of food processing apparatus formed according to an alternative embodiment of the present invention;

Figure 11 is a schematic illustration of food processing apparatus formed according to an embodiment of the present invention;

Figures 12 to 15 are front elevations showing various arrangements possible with the inclusion of a bulk tank;

Figure 16 is a flow chart representing a method of processing food in accordance with an aspect of the present invention; Figure 17 is a cross sectional view of an alternative embodiment of the food support structure located within the chamber of a food processing apparatus;

Figure 18 is a part perspective view of the food processing apparatus of Figure 17;

Figure 19 is cut-away perspective view along the line XIX of the food processing apparatus of Figure 18;

Figure 20 is a simplified schematic diagram of a food processing apparatus formed according to an aspect of the present invention;

Figure 21 is a view similar to that of Figure 20, but of an alternative embodiment; and Figure 22 is a view similar to that of Figures 20 and 21, but of a further alternative embodiment.

Referring now to Figures 2 and 3, there is shown a generally parallelepiped food support structure, generally indicated 203. The food support structure 203 is an open frame provided with three planar and rectangular food support shelves 213, which lie horizontally spaced within the body of the food support structure 203. Each of the food support shelves 213 is capable of supporting the weight of food 211 to be processed. The two food support shelves 213 positioned furthest from ground level 217 are perforated to allow liquid coolant to pass through them to the

food support shelf 213 situated below. In this embodiment, the food support shelf 213 located nearest the ground level 217 is not perforated and does not, therefore, allow liquid coolant to pass through to the ground level 217. Instead, liquid coolant is diverted by means of diverting means, here shown as diverting lips 219 located along opposite edges of the food support shelf 213 nearest ground level, to a liquid coolant sump, for example. The diverting lips are positioned externally of the body of the food support structure 203. The base shelf 213 of the structure may be cambered to improve drainage. The food support structure 203 is further provided with wheels 221 to allow the floor mounted food support structure 203 to be transported to and deposited on the base of a food processing chamber, for example. It will be appreciated that in other embodiments the food to be processed may not be placed on the lowermost shelf to ensure that the liquid coolant may drain from the food support structure more easily. This avoids the food becoming submerged in the liquid coolant.

Referring now to Figure 4, there is shown a cross-sectional view of a food support structure formed according to the present invention. Here, the food support structure is shown as a pallet, generally indicated 403. The pallet 403 is formed, from two rectangular panels 423 a and 423b, and two cross beams 425. The rectangular panels 423a and 423b lie substantially horizontally and are positioned parallel to one another, held together by the cross beams 425. The cross beams 425 extend along the entire length of the rectangular panels 423a and 423b, the cross beams 425 having a square cross section. From the view shown in Figure 4,

it can be seen that panel 423b rests on ground level 417, whilst panel 423a supports food 411 to be processed.

Now referring to Figure 5, there is shown a food support structure 503 having liquid coolant diverting means 519 formed according to an alternative embodiment of the present invention. The food support structure 503 is similar to the food support structure 203 shown in Figures 2 and 3, except that the liquid coolant diverting means 219 are replaced with liquid coolant diverting means 519. hi this embodiment, the liquid coolant diverting means 519 take the form of a rectangular prism, its orientation being- such that the base of the prism rests on the food support shelf 513 nearest ground level, whilst the apex of the prism points towards the remaining food support shelves 513 situated thereabove. The sloped walls of the prism 519 ensure that any used liquid coolant that falls towards the food support shelf 513, nearest ground level 517, is diverted away from and outside the body of the food support structure 503 along the sloped walls of the prism 519.

Now referring to Figure 6, there is shown. a preferred arrangement of food to be processed 611 when placed on adjacent and parallel food support shelves 613a- 613d of a food support structure 603. hi this embodiment, the food support structure 603 comprises four food support shelves 613a-613d, food support shelf 613a being located nearest ground level 617 and the remaining shelves 613b-613d being located intermittently further away from ground level 617. The food to be processed 611 is positioned on the food support shelves 613a-613d in a pattern such that each piece of meat 611 in a row is not directly above a piece in a row

below it. As a consequence of this offset, 'brick bond' formation any liquid coolant that passes through the gap 627 between adjacent pieces of food 611 placed on the food support shelf 613d, for example, will fall directly onto a further piece of food 611, placed on the food support shelf 613c below, which is aligned with the gap 627. An arrangement of this type increases the surface area of food 611 which may potentially come into contact with liquid coolant.

Now referring to Figures 7 and 8, there is shown a perspective view of a food processing apparatus, generally indicated 701. The food processing apparatus 701 comprises a chamber 705, having a rectangular prism-like shape, a door 731, two liquid coolant collection vessels 729, and a plurality of showering devices 709.

The showering devices 709 are situated on the ceiling of the food processing chamber 705, and are capable of supplying liquid coolant to the interior of the chamber 705. Showering devices on other walls are, of course, possible. The elongate liquid coolant collection vessels 729 extend along both longer sides of the rectangular base 735. The collection vessels 729 are elongate and have a rectangular cross-section and extend along the entire length of the base 735 of the chamber 705. The base 735 is capable of receiving and supporting a food support structure as described in more detail below. The door 731 is provided with door hinges 733 so that it may be closed during the processing of food, thereby minimising the risk of contamination of the food and providing a homogeneous atmosphere within the chamber.

Now referring to Figure 9, there is shown a cross-sectional view of a food support structure 903 situated within the food processing apparatus 701 of Figures 7 and 8. More specifically, the food support structure 903 is situated within the chamber 705 of the food processing apparatus 701. The food support structure 903 is substantially similar to the food support structure of Figures 2 and 3. It can be seen that the food support structure 903 has been rolled into the chamber 705 by means of the wheels 921 rotatably connected to the base of the food support structure 903. Accordingly, the wheels 921 are in contact with the base 735, of the chamber 705, and due to their spacing are able to pass in between the liquid coolant collection vessels 729. In this embodiment, each wheel 921 has a diameter greater than ^' the height of the liquid coolant collection vessels 729 thereby enabling the body of the food support structure 903 to fit inside the chamber 705 and be raised over the liquid coolant collection vessels 729; however, it is possible, in other embodiments, that the diameter of the wheels is less than the height of the collection vessel(s) and as a result this will minimise the level of any contamination which may be transferred between the wheels and the vessel(s). Where the diameter of the wheels is less than the height of the collection vessel(s), it will, of course, be necessary to provide the support structure with wheel brackets or feet to ensure that there is sufficient clearance over the collection vessel(s). The food support structure 903 is also provided with liquid coolant diverting lips 919, so that any liquid coolant reaching the impermeable and lowest food support shelf is diverted or redirected from the sides, over the lips 919, and into the liquid coolant collection vessels 729 located therebelow.

Now referring to Figure 10, there is illustrated an alternative embodiment of the present invention. In this embodiment, there is shown food processing apparatus, generally indicated 1001, comprising a food processing chamber 1005, and sunken liquid coolant sump 1029. The chamber 1005 has a rectangular prism-like shape and is located above the liquid coolant sump 1029. The liquid coolant sump 1029 being located below ground level 1017. The base of the food processing chamber 1005 is provided by a perforated grill 1035, wherein the mesh size of the grill is sufficient to allow only liquid coolant to pass therethrough and into the sump 1029. In this way, the grill 1035 is capable of receiving and supporting a food support structure during the processing of food. A food support structure may, therefore, be deposited on the grill 1035 for processing, which includes stages such as cooking and cooling for example, and then withdrawn from the grill after the processing of the food is complete.

The food processing apparatus 1001 is provided further with a primary conduit 1039 which connects the sump 1029 with a liquid coolant pump 1037, the pump 1037 also being connected to a showering device 1009, located on the ceiling interiorly of the chamber 1005, by a secondary conduit 1041. The primary conduit 1039, secondary conduit 1041 and pump 1037 provide the function of recirculating any liquid coolant which is passed into the sump 1029, after having percolated through the food supported on a food support structure, for example.

Referring now to Figure 11, there is illustrated a schematic diagram of part of food processing apparatus formed in accordance with the present invention. The food

processing apparatus, generally indicated 1101, comprise two liquid coolant collection vessels 1129a and 1129b located within a food processing chamber (not shown), means for supplying liquid coolant, such as a showering device 1109, to the chamber, and a bulk liquid coolant storage tank 1143. The liquid coolant collection vessels 1129a and 1129b are connected by a vessel-to-vessel conduit 1145, the liquid coolant collection vessel 1129a being connected to the bulk liquid coolant storage tank 1143 by means of a tank supply conduit 1147, and the bulk liquid coolant storage tank 1143 being connected to the liquid coolant collection vessel 1129b by means of a vessel supply conduit 1149, thereby completing a circuit around which liquid coolant 1151 may be circulated and recirculated. The flow of liquid coolant 1151 is shown by multiple arrows interspersed among the various conduits, described above. The liquid coolant collection vessel 1129a has an additional chamber supply conduit 1153 for supplying the chamber with liquid coolant through the showering device 1109. In alternative embodiments the liquid coolant may be supplied to the chamber directly from the bulk liquid coolant storage tank.

In this embodiment, the liquid coolant 1151 is brine, and therefore the apparatus 1101 is provided with means for adjusting parameters such as the concentration of salt within the brine 1151. Accordingly, the bulk liquid coolant storage tank 1143 comprises a salt hatch 1157, through which additional salt may be deposited to increase the salt concentration of the brine, and a mains water conduit 1159 for introducing more water into the system thereby decreasing the concentration of salt 1155 in the brine 1151. Preferably, the brine solution is retained in a fully

saturated state. The liquid coolant collection vessel 1129b is also provided with a mains water conduit 1161 for the same purpose of introducing water into the system, but at a different location.

The liquid coolant collection vessel 1129a is shown to comprise a thermostat 1163 which is capable of sensing a change in temperature of the liquid coolant 1151 within the system and subsequently sending a signal to a controller 1165, which in turn activates a heat exchanging element 1167 in order to adjust the liquid coolant temperature in response to the detected temperature. This could, for example, be in order to return the temperature of the liquid coolant 1151 to a pre-determined value such as 5 ⁰ C, for example. In alternative embodiments the bulk tank, or reservoir, may function as a separate entity to the liquid coolant collection vessels, in that the bulk tank may hold liquid coolant at a predetermined temperature, which liquid coolant may be interchanged with the collection vessels to adjust the temperature of the liquid coolant therein. A bulk tank can operate to regulate the temperature, and other parameters, of the liquid coolant residing in multiple collection vessels of multiple chambers, for example, hi some embodiments the liquid coolant may be supplied directly to the processing chamber from the bulk tank. The controller 1165 may, in alternative embodiments, perform additional and/or alternative functions such as the regulation of the concentration and flow rate of liquid coolant.

In addition, the bulk liquid coolant storage tank 1143 includes a filter bed 1173 for filtering any contaminants that may enter the system, insulation means, here

depicted as a jacket 1169, for retaining the temperature of the liquid coolant 1151 thereby enhancing its ability to act as a "cold sink", and an overflow conduit 1171 for the removal of excess liquid coolant 1151 from the system.

Referring now to Figure 12, there is shown a front elevation of food processing apparatus, generally indicated 1201, together with food support structure 1203 deposited therein. The apparatus 1201 is similar to the apparatus 701 of Figure 9, except that it further comprises a reservoir 1277 and a bulk tank 1243. From Figure 12 it can be seen that the reservoir 1277 is essentially a header tank and resides above the food processing chamber 1205. Numerous arrows show the flow of liquid coolant 1251 between the various components of the food processing apparatus 1201. More specifically, liquid coolant would, after percolating through the food (not shown) on the food support structure 1203, be directed into the collection vessel 1229, located at the side of the food support structure 1203 within the chamber 1205. From there, the liquid coolant 1251 is pumped by a pump 1275a to the reservoir 1277, where it may be held and stored. The liquid coolant 1251 may then be pumped by pump 1275b from the reservoir 1277 to the showering devices 1209 located within the chamber 1205. The liquid coolant 1251 present in the reservoir 1277 may also be interchanged with liquid coolant 1251 present in the bulk tank 1243 by means of a pump 1275c. Accordingly, the temperature, and other parameters of the liquid coolant 1251 in the reservoir 1277 may be regulated.

Referring now to Figure 13 there is illustrated a front elevation of food processing apparatus arrangement which is substantially similar to the arrangement shown in Figure 12. Accordingly, like reference numerals represent like features. The differences between Figure 13 and Figure 12 include the liquid coolant collection vessel 1329 which is, in Figure 13, represented by a channel formed within the food support structure 1303 itself as opposed to it being a separate vessel as shown in Figure 12. In this way, liquid coolant 1351 may percolate through the food (not shown) and be directed into the channel 1329, from where it may be circulated in a similar fashion to that described in relation to Figure 12. A further difference between Figures 12 and 13 is that the liquid coolant 1251 is, in Figure 13, conveyed internally of the chamber 1305, as opposed to externally of the chamber 1205, as depicted in Figure 12.

Referring now to Figure 14, there is shown a front elevation similar to that shown in Figure 12. All the features of Figure 12 are present in Figure 14, which are referenced with like reference numerals, except that Figure 14 is devoid of a reservoir as shown in Figure 12. The circulation route of the liquid coolant 1451, again shown by arrows, is from the liquid coolant collection vessel 1429 to the bulk tank 1443, from where it is fed directly to the showering devices 1409 located within the chamber 1405. The temperature, for example, of the liquid coolant 1451 which is received by the chamber 1405 will, therefore, be substantially similar to the temperature of the liquid coolant 1451 being transmitted from the bulk tank 1443. Of course, it is possible that the bulk tank may regulate this temperature, but in the absence of a reservoir the temperature of the liquid coolant

1151 supplied to showering devices in a plurality of chambers will be substantially the same.

Referring now to Figure 15, there is illustrated a front elevation substantially similar to that shown in Figure 14. This arrangement comprises all the features of

Figure 14, and so is referenced with like reference numerals, except that the liquid coolant collection vessel 1429 of Figure 14 is replaced with liquid coolant collection vessel 1529. The liquid coolant collection vessel 1529 is a channel formed in the food support structure 1503, more specifically in its lower most located shelf 1513. The liquid coolant 1551 is therefore transmitted directly from the channel 1529, of the food support structure 1503, and takes a path substantially similar to that detailed in relation to Figure 14.

Figure 16 shows a flow chart comprising the steps of a method for processing food associated in accordance with the present invention. Accordingly, step 'A' is providing a processing chamber having an unobstructed threshold. Step 'B' is manoeuvring a floor mounted food support structure over the threshold. Step 'C is depositing the structure in the chamber. Step 'D' is processing food supported by the structure, which includes the steps of cooking the food, before showering it with liquid coolant. Step ε' is removing the food support structure from the chamber, most likely to be after the completion of the processing of the food. Typically the chamber at step 'A' is provided with means for supplying liquid coolant to its interior and step 'D' is a cooling step.

Referring now to Figures 17, 18 and 19, there is shown a food processing apparatus formed according to an alternative embodiment of the present invention. This embodiment is similar to that shown in Figure 9 and, therefore, like reference numerals represent like features. The food processing apparatus 1701 is provided with a plurality of showering devices 1709 evenly spaced across the ceiling of the chamber 1705. The food support structure 1703 is provided with ground engaging legs 1721, as opposed to wheels 921 shown in Figure 9, which rest on the chamber base 1735. The food support structure 1703 comprises twelve food support shelves 1713 with food to be processed 1711 placed thereon, hi this embodiment, the liquid coolant diverting means are provided by drainage holes 1719 located at the food support structure base 1712 (best seen in Figure 18 and 19), as opposed to the liquid coolant diverting means 919 shown in Figure 9. The liquid coolant, therefore, is able to drain from the food support structure base 1712 into the liquid coolant collection vessels 1729 through the drainage holes 1719.

Referring now to Figure 20, there is shown a schematic diagram of a food processing apparatus 2001 comprising a chamber 2005 housing a food support structure 2003, a plurality of shower devices 2009, liquid coolant collection troughs 2029 and a liquid coolant bulk tank 2043. In this embodiment, arrows are shown to indicate the direction of travel of the liquid coolant as it is exchanged between the liquid coolant collection trough 2029 and liquid coolant bulk tank 2043; the shower devices 2009 being fed only by the collection trough 2029. The exchange of liquid coolant between the collection trough 2029 and the bulk tank

2043 allows parameters such as the concentration or temperature of the liquid coolant to be regulated.

With reference to Figure 21, there is illustrated a schematic diagram similar to that of Figure 20 but comprising a reservoir 2177. In this embodiment, liquid coolant is exchanged between the collection trough 2129, reservoir 2177 and bulk tank 2143; the plurality of shower devices 2109 being fed only by the reservoir 2177. The inclusion of a reservoir 2177 allows greater control over the parameters mentioned in relation to Figure 20.

Referring now to Figure 22, there is shown a schematic diagram similar to that of Figure 20, but of an alternative embodiment. In this embodiment, the liquid coolant is not exchanged between the collection trough 2229 and bulk tank 2243, as shown in Figure 20. Instead, liquid coolant travels directly from the collection trough 2229 to the bulk tank 2243 which feeds the showering devices 2209; the liquid coolant then being recirculated.