Standard animal processing methods are used throughout the meat processing industry to prepare animal carcasses for both exporting and supplying to local markets. One of the biggest problems in animal processing is the introduction of spoilage and pathogenic bacteria to the carcass during processing. Contamination of a carcass can occur through many practices, such as a general lack of hygiene and cleanliness in a processing plant, cross- contamination from the skin and organs of a carcass to the meat during skinning and/or evisceration and prolonged exposure to elevated temperatures which enhance microbial growth.

Any poor standards of hygiene during slaughtering or carcass handling can result in high levels of microbial contamination in the meat, reducing shelf-life of the product due to excessive contamination with spoilage bacteria and food safety hazards due to contamination with pathogenic bacteria. This can affect the acceptability of the product into foreign markets.

Carcasses that are processed for export to some markets are subject to rigorous biological testing to be eligible for export to the country. There is therefore a need to develop a simple, cost effective method for processing animal carcases that minimises microbial contamination as much as possible. Animal carcasses are usually processed using a standard method that involves stunning the animal to render it unconscious, cutting the throat to kill the animal and allow blood to drain from the animal, removal of the skin and removal of the internal organs. The organs are typically packed and refrigerated and carcasses placed in an air chiller to lower the carcass temperature to 7°C or lower. Following chilling, carcasses are typically boned and packed.

There are a number of disadvantages with the currently used method. During the removal of the skin there is a huge potential for cross contamination of the meat. Animal skins contain very high numbers of bacteria, which may be transferred to the animal carcass during skin removal. Additionally, skin removal is typically conducted near the beginning of the process, before refrigeration has occurred. This warm environment provides an excellent breeding ground for spoilage and pathogenic bacteria.

A further contamination risk occurs during evisceration and removal of the internal organs. Again, this is typically conducted at room temperature which provides optimal growing conditions for any bacteria present. Removal of the gastrointestinal tract also exposes the carcass to contamination risk if, for example, part of the intestine, stomach or bowel is perforated or leaks during removal. Current practices typically require a worker to wash their hands and sterilise the knife a number of times during the processing of a single carcass, largely due to the unsanitary state of the hide. It would be useful to provide a method of animal processing that reduces the need for multiple occurrences of hand/knife washing and/or sanitation during processing. An improved animal processing method is described in PCT Patent Application No.

PCT/NZ2014/000073, the entire contents of which are incorporated herein by reference. In this application a method of animal processing is disclosed in which the blood is removed using a minimally invasive process, and then the carcass is chilled or frozen to preserve the carcass for storage and/or exportation, prior to hide removal and evisceration. The hide remains on the carcass during storage/transportation, providing a barrier to external bacteria present on both the external surface of the hide and in the processing environment, and the gastrointestinal tract remains in the carcass.

Further improvements of animal processing methods are desired. It is therefore an object of the invention to provide an improved method of processing an animal carcass. For a commercial operation, a fast speed of processing animal carcasses is desirable to increase carcass output and to increase the revenue that can be generated in a given period of time. It is therefore desirable to increase the rate at which animal carcasses can be cooled. Similarly, for later processing of the animal carcasses, it is desirable to increase the rate at which the animal carcasses can be warmed and consequently processed.

Alternatively, it is an object of the invention to at least provide the public with a useful choice.

Summary of the Invention

Conventionally, carcasses are skinned and eviscerated prior to being chilled or frozen for preservation purposes. Subsequently, if exported in a frozen state then the carcass is warmed for further processing. When conventionally processed carcasses are cooled or warmed, the abdominal area of the carcass is cooled or warmed at the same rate as the outside of the carcass since the eviscerated carcass has both its external and internal surfaces exposed to the cooling or heating medium. However, in the case of a carcass that is cooled and subsequently warmed prior to hide removal and evisceration (an "intact" carcass), the internal surfaces of the carcass are difficult to expose to the cooling or heating medium, for example in an air freezer or water bath. As a result, conventional carcass cooling and warming processes will cool or warm an intact carcass slowly, which is undesirable for a commercial operation.

Aspects of the present invention provide an improved apparatus and methods for cooling and warming an intact carcass. Preferred aspects of the present invention are set forth in the appended claims. Particular embodiments of the invention are described below in non-limiting terms. According to a first embodiment of the invention, there is provided a method of altering the temperature of an animal carcass, the method comprising:

inserting an elongate device into the gastrointestinal tract of the carcass; and injecting a heat transfer medium into the elongate device such that the heat transfer medium is brought into thermal contact but not physical contact with the carcass.

In preferred embodiments, the heat transfer medium has a lower temperature than the temperature of the carcass in order to cool the carcass when the heat transfer medium is injected into the elongate device.

Preferably, the method comprises inserting the elongate device into the colon of the carcass. More preferably, the method comprises inserting the elongate device into the colon by way of the anus of the carcass.

Preferably, the method comprises circulating the heat transfer medium through the elongate device.

Preferably, the method comprises the step of removing the elongate device from the carcass after the step of injecting the heat transfer medium into the elongate device and once the carcass has reached a desired temperature.

More preferably, the method comprises cooling the carcass with the heat transfer medium until at least those parts of the carcass proximate the elongate device are frozen so that, when the elongate device is removed from the carcass, a cavity is left in the carcass.

Preferably, the method comprises cooling the carcass prior to hide removal and evisceration.

Preferably, the method comprises removing blood from the carcass prior to cooling the carcass. Preferably, the method comprises controlling the rate of temperature change of the carcass to avoid undesirable organoleptic properties of the carcass and/or of meat produced from the carcass. According to a second embodiment of the invention, there is provided a method of processing an animal carcass, the method comprising:

inserting an elongate device into the gastrointestinal tract of the carcass;

injecting a cooling heat transfer medium into the elongate device such that the cooling heat transfer medium is brought into thermal contact but not physical contact with the carcass; and

supplying heat to the gastrointestinal tract of the carcass.

Preferably, the step of supplying heat to the gastrointestinal tract comprises injecting a warming heat transfer medium into the gastrointestinal tract of the carcass such that the warming heat transfer medium is brought into thermal contact with the carcass.

Preferably, the method comprises the step of removing the elongate device from the carcass after the step of injecting the cooling heat transfer medium into the elongate device and once the carcass has reached a desired temperature.

More preferably, the method comprises cooling the carcass with the heat transfer medium until at least those parts of the carcass proximate the elongate device are frozen so that, when the elongate device is removed from the carcass, a cavity is left in the carcass. Furthermore, the step of injecting the warming heat transfer medium into the gastrointestinal tract comprises injecting the warming heat transfer medium into the cavity.

According to a third embodiment of the invention, there is provided a method of warming an animal carcass, the method comprising:

receiving an animal carcass that has been cooled by a method according to the first embodiment of the invention; injecting a warming heat transfer medium into the gastrointestinal tract of the carcass such that the warming heat transfer medium is brought into thermal contact with the carcass.

In one embodiment, the step of injecting the warming heat transfer medium into the gastrointestinal tract may comprise injecting the warming heat transfer medium into an elongate device inserted into the gastrointestinal tract. Furthermore, the method may comprise inserting the elongate device into the gastrointestinal tract of the carcass after receiving the carcass. According to a fourth embodiment of the invention, there is provided a method of warming an animal carcass, the method comprising:

receiving an animal carcass that has been cooled by a method according to the first embodiment of the invention;

inserting an elongate device into the gastrointestinal tract of the carcass; and supplying heat to the carcass from the elongate device.

Preferably, the step of supplying heat to the carcass comprises injecting a warming heat transfer medium into the elongate device such that the warming heat transfer medium is brought into thermal contact but not physical contact with the carcass.

According to a fifth embodiment of the invention, there is provided an animal carcass processed using the method of any one or more of the first, second and third embodiments of the invention. According to a sixth embodiment of the invention, there is provided a device for use in altering the temperature of an animal carcass, the device comprising:

an elongate housing having an open end and a closed end; and

first and second fluid conduits inside the elongate housing, the first and second fluid conduits being fluidly coupled proximate to the closed end of the elongate housing, wherein the first fluid conduit is configured to receive an inflow of a heat transfer medium through the open end of the elongate housing, and the second fluid conduit is configured to allow an outflow of the heat transfer medium through the closed end of the elongate housing, and

wherein, in use, the heat transfer medium in the first and/or second fluid conduit is in thermal contact with the carcass.

Preferably the closed end of the elongate housing is configured to avoid rupturing a part of the gastrointestinal tract of the carcass when the device is inserted into said part. More preferably, the closed end comprises a rounded end.

In one embodiment, the first fluid conduit is positioned radially central to the elongate housing and the second fluid conduit is positioned radially outwards from the first fluid conduit. More preferably, the second fluid conduit has an annular or annular-like cross-sectional shape such that the second fluid conduit radially surrounds the first fluid conduit.

In an alternative embodiment, the first fluid conduit is positioned on a first lateral side of the elongate housing and the second fluid conduit is positioned on a second lateral side of the elongate housing.

More preferably, the first fluid conduit is fluidly coupled to a funnel means, the funnel means being configured to collect the heat transfer medium when sprayed over the carcass and to funnel the collected heat transfer medium into the first fluid conduit. More preferably, the device is configured such that the first fluid conduit is positioned above the second fluid conduit.

Further aspects of the invention, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading of the following description which provides at least one example of a practical application of the invention. Brief Description of the Drawings One or more embodiments of the invention will be described below by way of example only, and without intending to be limiting, with reference to the following drawings, in which:

Figure 1 is a diagram illustrating the gastrointestinal tract of a rumen; Figure 2 is a cross-sectional side view diagram of a carcass colon cooling device according to one embodiment of the invention;

Figure 3 is a cross-sectional side view diagram of a carcass colon cooling device according to another embodiment of the invention;

Figure 4 is a flowchart illustrating an exemplary method of processing an animal carcass according to one embodiment of the invention;

Figure 5 is a flow chart illustrating an exemplary method of cooling an animal carcass according to one embodiment of the invention;

Figure 6 is a flow chart illustrating an exemplary method of warming an animal carcass according to one embodiment of the invention; and Figures 7-9 are graphs illustrating data captured from an intact carcass when thawed having been frozen using a colon cooling device such as shown in Figure 2. Detailed Description of Preferred Embodiments of the Invention Intact carcass cooling

As mentioned above, PCT Patent Application No. PCT/NZ2014/000073, the entire contents of which are incorporated herein by reference, discloses a method of animal processing in which the animal's blood is removed using a minimally invasive process, and then the carcass is chilled or frozen to preserve the carcass for storage and/or exportation, prior to hide removal and evisceration. The hide remains on the carcass during storage/transportation, providing a barrier to external bacteria present on both the external surface of the hide and in the processing environment, and the gastrointestinal tract remains in the carcass. It will be understood that the step of removing blood from the carcass does not necessarily require the animal to already be dead when the blood is removed. The act of removing the blood from the animal may kill the animal (exsanguination). Throughout this specification the term 'carcass' is therefore used to mean both a dead animal's body (or parts thereof) and an animal's body prior to death, unless the context makes it clear otherwise.

In this specification, animal carcasses that are processed in line with the method outlined in PCT/IMZ2014/000073, i.e. carcasses that are preserved for storage/transportation purposes with the blood removed but the hide and viscera still substantially in place, will be referred to as 'intact' carcasses. This term is used merely as a convenient label to refer to such carcasses and is not intended to be interpreted in any way that is limiting to the invention, for example if some parts of the carcass are altered in some way.

For the purposes of this document, the act of 'freezing' an animal carcass is understood to be the act of cooling the carcass so that at least some of the parts of the carcass have a temperature of less than 0°C. For example, the deep carcass tissues may be considered when assessing whether the entire carcass is frozen as these tissues often freeze slowest. The carcass may be cooled in any appropriate manner, including (without limitation) the exemplary cooling methods described herein. In some exemplary embodiments of the invention, the entire carcass may be considered to be "frozen" (i.e. the step of freezing has been completed) once all parts of the carcass have a temperature of less than 0°C. Individual parts of the carcass may be considered frozen when those parts have a temperature of less than 0°C. Alternatively, the entire carcass or a carcass part may be considered frozen when all parts of the carcass or the relevant carcass part have reached a temperature of -1.8°C or less since -1.8°C is one commonly regarded measure of the freezing point of meat. Therefore, although liquids within a carcass may freeze at or about 0°C, the solids (e.g. meat, organs, other tissue) may freeze at or about - 1.8°C.

PCT/NZ2014/000073 describes cooling an intact carcass by the internal or external application of a cooling medium such as brine. The external application or brine described in

PCT/NZ2014/000073 involves immersing, or partly immersing, the carcass in a bath of brine and/or spraying external parts of the carcass with brine. The internal application of brine described in PCT/NZ2014/000073 involves flushing brine into the stomach of the carcass through the oesophagus. One problem with the method of internally applying cooling brine described in

PCT/NZ2014/000073 is that the brine used for flushing the stomach becomes significantly contaminated with the contents of the carcass' stomach during flushing. In a commercial operation where multiple carcasses are processed using this method, either new brine would have to be provided for flushing the stomach of each carcass or the stomach would have to be downgraded to rendering material. The cost of providing new brine for each carcass and cooling the brine for a single use may be prohibitive for a commercial operation or may reduce profitability. Similarly, lost revenue from downgrading the stomach to rendering material rather than utilizing it for edible tripe is also likely to be prohibitive for a commercial operation, or at least reduces the profitability of such an operation. Cooling of an intact carcass using an internal cooling device

Embodiments of the invention propose as a solution to the above mentioned problem the use of a cooling device inserted into the gastrointestinal tract of the carcass.

Figure 1 is a diagram illustrating the gastrointestinal tract of a rumen. Figure 1 illustrates a goat but it will be understood by the skilled addressee that the gastrointestinal tract of all ruminants (e.g. sheep, cattle, deer and camels) is very similar. The lower part of the large intestine, i.e. the terminal part of the colon leading to the rectum and anus, is relatively straight. This can be seen in the section labelled 'large intestine' in Figure 1. In addition, this part of the gastrointestinal tract is elastic in nature. Similar properties of the lower gastrointestinal tract of a rumen are also found in other animals, for example pigs and horses.

These properties of the colon provide the opportunity to insert an elongate device into the colon through the anus and to use the elongate device to facilitate cooling of the carcass.

Exemplary colon cooling devices

Figure 2 is a cross-sectional side view diagram of a carcass colon cooling device 10 according to one embodiment of the invention. Cooling device 10 is a generally elongate tube-like device into which a heat transfer medium can be injected in order to internally cool a carcass.

More particularly, cooling device 10 comprises an elongate housing 11. In preferred

embodiments the elongate housing 11 is generally cylindrical although in other embodiments the housing may have a non-circular cross-section, e.g. an oval cross-section. Housing 11 has a closed end 12 and an open end 13 at the other end of the elongate housing from closed end 12.

Inside housing 11 are defined fluid conduits allowing the flow of a heat transfer medium. An inner fluid conduit 14 is positioned radially central to the elongate housing 11. In the annular space radially surrounding inner fluid conduit 14 is defined an outer fluid conduit 15. It will be understood that inner fluid conduit 14 may be held in place by means of struts or the like extending outwards from the inner surface of the outside of housing 11. In the embodiment of Figure 2, outer fluid conduit 15 comprises a single fluidly connected annular conduit but, in other embodiments, multiple fluid conduits positioned radially outward from the first fluid conduit 14 may be provided. It will be understood that, to the extent "annular" is considered to mean circularly ring-shaped, in embodiments in which elongate housing 11 has a non-circular cross-section, the cross-sectional shape of outer fluid conduit 15 may be annular-like, e.g. ovally ring-shaped or the like. Inner and outer fluid conduits 14 and 15 are fluidly connected proximate to the closed end 12 of the housing 11. The fluid connection of these conduits is achieved by the termination of inner fluid conduit 14 with a spacing from the inside of the end wall of the housing at the closed end 12. As a result, fluid passing through the inner fluid conduit 14 is able to flow into the outer fluid conduit 15 (and vice versa).

At the open end 13 of housing 11, the inner and outer fluid conduits are configured to be fluidly connected to an inflow and outflow of heat transfer medium. The conduits may be connected to a source or depository of a heat transfer medium via any appropriate connection

mechanism. Suitable connection mechanisms will be apparent to those skilled in the art.

In one exemplary embodiment, inner fluid conduit 14 is connected to an inflow or supply of heat transfer medium, for example a hose line into which heat transfer medium is injected from a heat transfer medium reservoir. Outer fluid conduit 15 is connected to an outflow pipe which discharges heat transfer medium to a receiving reservoir. As a result, the heat transfer medium flows through the inner fluid conduit 14 then through the outer fluid conduit 15.

In another embodiment the heat transfer medium may flow through cooling device 10 the other way, i.e. the heat transfer medium may be injected into the outer fluid conduit 15 and exit the device from the inner fluid conduit 14. Whether the heat transfer medium flows into the outer tube or out of the outer tube, the heat transfer medium in the outer tube is, in use, in thermal contact with the carcass and therefore cools the carcass as will be described in more detail below. Figure 3 is a cross-sectional side view diagram of a carcass colon cooling device 20 according to another embodiment of the invention. Cooling device 20 comprises an elongate housing 21 in which are formed an upper conduit 22 and a lower conduit 23. The internal volume of the elongate housing 21 is segregated into upper and lower conduits 22 and 23 by means of a divider or septum 24, which runs along the length of housing 11 but has an end spaced from the inner surface of the closed end of housing 21 to fluidly connect the upper and lower conduits. It will be apparent to the skilled addressee how the septum may be supported inside the housing 21, for example using struts. The heat transfer medium when in both the upper and lower conduits 22 and 23 is in thermal contact with the carcass and therefore acts to cool the carcass.

Lower conduit 23 is fluidly connected to a fluid outlet 25. Upper conduit 22 is fluidly connected to a collector or funnel means 26. In the embodiment of the invention shown in Figure 3, funnel means 26 comprises a funnel or wide diameter port. In use, heat transfer medium that is sprayed or poured onto the carcass is collected by funnel 26 and funnelled into upper conduit 22. The outlet 25 from lower conduit 23 is positioned below funnel 26, but above the level of the septum (so that the lower conduit is always completely full) and may be turned

downwardly, to prevent deluge spray from entering the outlet. Alternative devices for allowing inflow into the upper conduit may be provided in other embodiments of the invention. In use, the cooling devices 10 and 20 of Figures 2 and 3 may be used with a fluid circulation apparatus so as to re-circulate heat transfer medium between the fluid conduits of the cooling device and a heat transfer medium reservoir. The fluid circulation apparatus may be configured to cool the heat transfer medium and transfer heat away from the carcass (via absorption of heat in the cooling device) using a refrigeration cycle in any appropriate manner that will become apparent to the skilled addressee. It is desirable to reduce the possibility of the elongate housing of the cooling device from perforating, rupturing or otherwise damaging the colon or other part of the gastrointestinal tract of the carcass into which the cooling device is inserted. To this end, the closed end of the housing (which is the end which is first pushed into the carcass) may be rounded, bevelled or otherwise devoid of sharp edges and/or structures that may damage the gastrointestinal tract of the carcass.

A cooling device as described above may be of any suitable size and shape. Cooling devices according to embodiments of the invention may have a size and shape dictated by the nature of the intended use of the device, for example, the type and size of animal with which the device will be used.

In one example, a cooling device that has found to be suitable for insertion into the colon of an average sized lamb (live weight approximately 30-40kg) may be approximately 250-600mm long, for example 300-500mm long, for example 400-450mm long, with an outside diameter of approximately 30mm. The inner diameter of the elongate housing may be approximately 25mm. A cooling device as shown in Figure 2, i.e. with a central inner conduit, may have a central inner conduit having an outer diameter of approximately 8mm and an inner diameter of approximately 5mm. Unless otherwise specified, the invention is not limited to the size of any particular component of the cooling device and these dimensions are provided for explanatory purposes only.

In some embodiments the cooling device is formed from a flexible plastics material. A material having some flexibility helps to reduce the risk of the device perforating or damaging the gastrointestinal tract on insertion or withdrawal. However, in other embodiments, other materials may be used, for example semi-rigid plastics or rigid plastics, other composite materials or metals. The configurations of cooling devices illustrated in Figures 2 and 3 are illustrative examples and other configurations of cooling device may be provided in other embodiments of the invention. In general, the cooling device needs to be elongate so that it can be inserted into the gastrointestinal tract of an animal, and to have at least two conduits able to receive heat transfer medium, for example in a circulatory manner. While the internal conduits in the embodiments shown in Figures 2 and 3 are fluidly connected, in other embodiments, the internal conduits are not fluidly connected. Furthermore, there may be a plurality of conduits inside the housing of the cooling device, some of which are fluidly connected and some of which are not. In an alternative embodiment, the cooling device may simply comprise a length of hose that includes a U-bend or is doubled back on itself, the U-bend or kink in the hose being the end of the cooling device that is inserted into the gastrointestinal tract.

Exemplary method of animal processing An exemplary method of processing an animal carcass according to an embodiment of the invention will now be described with reference to Figure 4, which is a flowchart illustrating an exemplary method 400. The use of a cooling device such as the cooling devices described with reference to Figures 2 and 3 in the exemplary method 400 will be described further below. Further details of some of the steps of the intact carcass processing method are described in PCT Patent Application No. PCT/NZ2014/000073, the entire contents of which are incorporated herein by reference.

At step 401, the animal is subjected to a lethal head to body stun, using techniques readily available such as electrical head to body stunning. While a non-lethal stun may be used, the use of a lethal stun is preferable as it enables more effective minimally-invasive blood removal following the stun.

Following a lethal stun at step 401, the animal may then be exsanguinated at step 402, for example using a sterilised 10 to 14-gauge hypodermic needle, inserted into the jugular vein. The blood may be collected for later use (subject to the carcass being passed by the government approved meat inspector as fit for human consumption) if required or discarded. The use of a hypodermic needle may be preferable as it creates a very small puncture in the skin of the animal, particularly as the needle is hollow. Following removal of the needle, such small puncture wounds tend to substantially close up, providing minimal openings for bacteria or other micro-organisms. The blood of the animal has now been removed, with the hide substantially intact. While this is the preferred method of exsanguination, other minimally invasive methods may be used, provided there is minimal damage to the hide of the animal, for example a traditional stick cut or use of a vampire knife inserted into the artery to drain blood away from the animal. Alternative methods for performing this step, including halal methods, are discussed further in PCT Patent Application No. PCT/NZ2014/000073.

Following exsanguination at step 402, the stomach cavity of the animal is evacuated at step 403 using a stomach tube and flushed or sprayed with water until the water runs reasonably clear. In other embodiments, flushing of the stomach may occur using a range of different fluids, either in liquid or gas form. For example, the stomach may be flushed with one or more of carbon dioxide, nitrogen, compressed air or other inert gases to remove excess oxygen from the internal stomach, reducing the likelihood of metmyoglobin formation on intra-abdominal muscles. In alternative methods a vacuum may be applied to the stomach to remove excess oxygen, or the stomach may be flushed with deoxygenated water. In some embodiments more than one of the above methods may be combined, for example the stomach may be flushed with compressed air and suction may also be applied. The above methods of deoxygenating the stomach region are not intended to be limiting and other techniques known in the art may be used for the same purpose. The terminal colon may be evacuated and sanitised at step 404. Evacuation of the terminal colon may be performed using known techniques. Preferably the colon is flushed using water until it runs clear. Sanitisation may then take place by flushing the colon with ozone or 200ppm chlorine to remove and/or destroy any remaining bacteria. Other known disinfectants that are approved for use in meat processing may be used, as would be clear to a person skilled in the art. As with the evacuation and flushing of the stomach region at step 403, evacuation and flushing of the colon region at step 404 may also be performed using a range of different fluids, either in liquid or gas form.

Following evacuation and sanitisation of the colon, the animal hide may be shorn (particularly in the case of animals with a long fleece, e.g. sheep), washed and sanitised at step 405 to remove external bacteria. The hide is cleansed thoroughly to remove all organic matter, followed by sanitisation to kill bacteria present on the hide. The effective sanitisation of the hide is beneficial for maintaining a low bacterial count on the finished product at the completion of the storage period. Preferably, washing of the carcass takes place using an auto- immersion or auto-spray hide washing system using detergent and agitation, either mechanical or using water flow to dislodge dirt and other debris. Sanitation of the hide may be achieved by application of ozone or 200ppm chlorine for example. This is preferably achieved by submersion of the carcass in one or more immersion tanks or spraying with a series of high pressure sprays. The washing and sanitising step 405 may be repeated as needed until the hide is clean and sanitised.

The carcass and hide is then rinsed at step 406 by immersion or spraying with water.

Cooling of the carcass occurs at step 407. Cooling of the carcass may comprise external and/or internal refrigeration / cooling using any one or more of the cooling methods described herein. In the exemplary embodiment of the invention described herein, the step of cooling includes a method of internally cooling the carcass using a cooling device such as has been described with reference to Figures 2 and 3. An exemplary method of internally cooling a carcass using such a device is described further below.

Once cooled to the desired temperature, the carcass is stored at step 408. The exemplary method envisages that the frozen carcass is stored in a condition that is suitable for long term preservation and storage of the carcass and, optionally transport to a destination market, including exportation. Preferably, the carcass is preserved in a manner that minimises deterioration of the resulting meat product during its expected shelf life. That is, the carcass is preserved in a manner that ensures the meat produced from the carcass is edible and healthy once finally processed.

At step 409, the cooled (for example frozen), preserved carcass is received at a destination location and is processed to prepare meat for consumption. Typically, step 409 comprises at least the steps of thawing, skinning, evisceration, inspection by a government approved meat inspector and boning. An exemplary method of thawing a carcass using a device such as has been described with reference to Figures 2 and 3 is described further below. Other exemplary thawing methods are described in PCT Patent Application No. PCT/NZ2014/000073 and Australian Provisional Patent Application No. 2014904112, the entire contents of which are incorporated herein by reference.

Exemplary method of internally cooling an animal carcass using a cooling device A method of internally cooling an animal carcass using a cooling device such as described with reference to Figures 2 and 3 will now be described with reference to Figure 5, which is a flow chart illustrating an exemplary method 500 of cooling an animal carcass according to one embodiment of the invention. It will be understood that the steps of method 500 may be carried out as part of step 407 of the method of animal processing 400 described in relation to Figure 4, for example in addition to cooling applied to external parts of the carcass.

At step 501, a cooling device, such as cooling devices 10 and 20 described in relation to Figures 2 and 3, is inserted into the gastrointestinal tract of the carcass through the anus. In this exemplary method, the cooling device is inserted into the colon. Prior to inserting the cooling device the terminal colon should be emptied. As described at step 404 of animal processing method 400, this can be achieved by flushing the colon with water. Alternatively, a suction device may be used to suck the contents of the colon out.

The elongate shape of the cooling devices 10 and 20 and the rounded shape of the end that is pushed into the carcass (e.g. end 12 as shown in Figure 2) enables the cooling device to be inserted without use of excessive force and without the need for lubrication. However, a lubricant may be used in some embodiments of the invention. Excessive force is undesirable as it may cause damage to the colon or other parts of the gastrointestinal tract. However it has been found that, due to the elastic nature of the colon, it may be possible to push the cooling device in a further distance after some resistance is first encountered without causing damage.

At step 502, a heat transfer medium in the form of a cooling medium is injected into the conduits in the cooling device. In one embodiment of the invention, the cooling medium is brine cooled to a temperature in the range -24°C to -30°C. In other embodiments, other temperatures of cooling medium may be used, for example a temperature in the range -30°C to -40°C or -10°C to -24°C. In one embodiment the cooling medium is brine at a temperature of approximately -36°C. In other embodiments the cooling medium is at a temperature lower than -40°C. For example, liquid nitrogen may be used as the cooling medium, which may have a temperature of less than -196°C. It will be appreciated that the temperature of the internally applied cooling medium is important to the rate of cooling of an animal carcass. Typically, the temperature of the brine (or other cooling medium) applied to the carcass to cool it will be colder than the intended final temperature of the carcass. Generally speaking, the colder the temperature of the brine that is applied to the carcass, the faster the carcass will cool. Further consideration to factors that affect what cooling rates and brine temperatures are desirable is discussed below.

In other embodiments of the invention an alternative cooling medium may alternatively be used, for example any kind of fluid refrigerant. In addition, any type of salt may be provided in solution to constitute brine, although in preferred embodiments of the invention a CaCI ₂ solution is used. The cooling medium may include salt in solution at any suitable concentration, and examples of concentration levels used in trials are given below. The skilled addressee will appreciate that other concentrations of salt / brine may be used in other embodiments of the invention. As has been described, the cooling device inserted into the carcass may be configured to enable a cooling medium to be circulated between the cooling device and a cooling system in order to convey heat away from the carcass and enable it to cool. The cooling medium may be injected or pumped through the cooling device at a rate that enables the desired rate of cooling of the carcass. In one embodiment of the invention, the cooling medium is circulated through the cooling device at a rate of 2 litres per minute. In other embodiments other rates may be used. It will be appreciated that, in general, the higher the flow rate of cooling medium in the cooling device, the higher the rate of cooling. However, the increase in the rate of cooling diminishes as the flow rate increases.

Once the carcass has reached the target temperature, the cooling device is removed at step 503. The target temperature may be any temperature desired to be achieved after cooling of the carcass. However, in preferred embodiments, the target temperature is sufficiently cold to preserve the carcass in some manner in order to minimise or reduce deterioration of the product while maintained at or close to the target temperature, and/or during the expected shelf life of the meat produced from the carcass. For example, the target temperature of the carcass may be to freeze the carcass at any temperature of less than 0°C. In some embodiments the carcass is cooled to temperatures in the range -1°C to -20°C, for example -1°C to -5°C or - 12°C to -20°C. In still further embodiments the carcass is cooled to temperatures less than - 20°C.

In an alternative embodiment, the cooling device is left in the carcass and used later in the carcass processing method (as will be described later). However, removal of the cooling device may be preferable to enable the cooling device to be re-used at the carcass cooling facility, saving costs and reducing environmental waste.

Removal of the cooling device may be more difficult than simply pulling the device out. In one embodiment, the cooling device is removed from a frozen intact carcass by injecting warm or hot water (e.g. at 90°C) into the cooling device. It has been found that, if the warm or hot water is left in the tube for a short period of time, for example two to three minutes, it can be pulled out easily without actually thawing the colon so that the colon remains in a distended state. The space previously occupied by the cooling device inside the carcass remains as a cavity, which may be used later to help thaw the carcass, as will be described further below. Discussion on carcass cooling using the exemplary cooling device

The abdomen and pelvis are generally the slowest cooling parts of intact carcasses because they are thicker than other areas. For example, for one 28.7kg intact lamb carcass (carcass 14/4, slaughtered on 22/12/14), the thickness of the abdomen and pelvis was 150mm, whereas the next thickest part of the carcass (hind leg) was 100mm.

It is important for the abdomen and pelvis of intact carcasses to cool quickly due to the high concentration of mesophilic bacteria in the stomach and intestines, many of which are highly pathogenic. In comparison, the remaining parts of intact carcasses are generally completely sterile.

The thorax is the same thickness as the abdomen and pelvis, however the low density of tissue in this area makes it easier to cool and it only has a small amount of microbial contamination present (in the oesophagus).

Table 1 below shows cooling times of intact carcasses when cooled using a brine bath when an elongate cooling device is inserted into the carcass compared to when such a device is not used. To obtain the data, data loggers were inserted into the abdomen of lamb carcasses, just on the right side of the midline of the carcass, between abdominal vertebrae, level with the front of the wing of the ileum in front of the pelvis. Table 1 shows a comparison of the time taken to reduce the internal abdominal temperature at this location to 0°C.

Cooling

Time taken

Live Brine Cooling Abdominal rate of

Carcass to cool

Date weight temp. device Start abdomen ID abdomen to

(kg) (°C) used? temp. (°C) (°C per

0°C (hours)

hour) 14/1 4/12/14 32.0 -26.8 No 37.3 5.83 6.40

14/2 11/12/14 27.5 -40.0 No 38.8 4.62 8.40

14/3 15/12/14 28.0 -38.0 No 36.4 5.50 6.62

14/5 22/12/14 29.5 -36.0 No 34.3 4.62 7.42

15/7 1/3/15 28.6 -27.7 Yes 35.5 3.42 10.38

17/1 10/3/15 40.0 -29.5 Yes 32.3 3.88 8.32

17/3 10/3/15 43.9 -24.4 Yes 35.1 2.30 15.26

Table 1 - Time taken to reduce the internal abdominal temperature to 0°C in intact carcasses with or without a colon cooling device

Without colon tube:

Average brine temp: -34.0°C

Average start temp: 36.7°C

Average time to cool abdomen to 0°C: 5.14 hours

Average cooling rate: 7.14 °C per hour

Average live weight: 29.3 kg

With colon tube:

Average brine temp: -21. C

Average start temp: 34.3°C

Average time to cool abdomen to 0°C: 3.20 hours

Average cooling rate: 10.72 °C per hour

Average live weight: 37.5 kg

These results show that, even though the average temperature of brine for the carcasses where a colon cooling device was used was warmer (-27.7°C compared with -34°C) and the average weight of those carcasses was heavier (37.5kg compared with 29.3kg), the cooling rate in the abdomen was quicker than carcasses where a colon cooling device wasn't used (10.72°C per hour compared with 7.14°C per hour). Note that variation in brine temperature for each carcass is inherent in the brine refrigeration system used to obtain this data but the actual temperature was recorded during each trial.

New Zealand Provisional Patent Application No. 713441 ("NZ 713441"), the contents of which are herein incorporated by way of reference, explains that overly quick or overly slow cooling rates for cooling or freezing intact carcasses may be undesirable because of the organoleptic effects on the carcass meat. In particular, slow cooling rates can result in a yellowing of the abdominal fat / organs or an odour on the flap on the right hand side of the carcass where the caecum is located. As explained above, if only external refrigeration is applied to intact carcasses then the centre of the abdomen and pelvis are the last parts of the carcass to be cooled and this can result in such undesirable organoleptic effects. In comparison, if a cooling device as described herein is used to deliver internal cooling to the gastrointestinal tract of an intact carcass then the centre of the abdomen and pelvis are among the first parts of the carcass to be cooled and such organoleptic effects may be avoided.

NZ 713441 also describes undesirable effects on a carcass if it is cooled too quickly, namely undesirable tasting meat with a dark brown/mushy or burnt appearance on the abdominal muscles (commonly referred to as the "flaps" in the meat industry) and tenderloins (small muscle located under the abdominal vertebrae) on the left side of the carcass (i.e. the side where the rumen is located in ruminant animals), which may result in the meat produced from the carcass having a very strong and/or unpleasant taste. It has been found that the use of a colon cooling device as described herein does not cool the meat of a carcass sufficiently quickly to result in these undesirable effects. When cooling an intact carcass using a cooling device such as has been described above, the following factors may affect the rate at which the carcass is cooled: i. the temperature of the cooling medium;

ii. the rate of application of the cooling medium to the carcass; and/or iii. the concentration of the cooling medium. It will be appreciated that there is an interplay between these different factors and each may affect the rate of cooling in a different manner. When cooling a carcass using the cooling method 500 explained with reference to Figure 5, the aforementioned factors are selected to obtain the desired rate of cooling to avoid undesirable organoleptic effects in the carcass.

Thawing an intact carcass using a colon device

Above has been described the use of an elongate device for cooling the internal parts of an intact carcass. Such devices can advantageously also be used to thaw or warm an intact carcass, for example as part of step 409 of the exemplary method of animal processing 400, as will now be explained.

There are important considerations when thawing an animal carcass as part of a 'downstream' process, i.e. processing the carcass at step 409 after storage or transportation at step 408, for example after transportation to an importing country or other location remote from where the 'upstream' processing of the carcass occurs.

The cost of thawing a carcass is important. Cost can increase significantly when large amounts of energy are required. Similarly, if carcasses are thawed slowly, thawing facilities need to have a higher capacity to thaw a given number of carcasses in a given time, increasing costs.

The quality of the meat is also important. One phenomenon that can occur during thawing of a carcass with the hide intact is the formation of metmyoglobin (MMG) in the meat. After the skin on a carcass has thawed, oxygen can diffuse through the skin in low concentrations and react with myoglobin present in the meat to form MMG. It has been found that at low concentrations such as when oxygen diffuses through the thawed skin of a carcass, MMG development is greatest. As MMG causes discolouration of the meat and can adversely affect flavour and tenderness, it is desirable to minimise its formation. Minimising bacterial multiplication in the gastrointestinal tract is also important when thawing a carcass that has not been eviscerated. Gastrointestinal micro flora are present in a dormant state in a carcass that has been frozen without evisceration, however this micro flora cannot multiply below a certain temperature. It is important therefore that when thawing a carcass that still includes the gastrointestinal tract, the gastrointestinal tract is not sufficiently warmed for a sufficient period of time that there is an excessive outgrowth of bacteria.

PCT/NZ2014/000073 describes a basic process for thawing an intact carcass by submerging it in warm water (38°C) for 5 hours prior to dressing the carcass. Later trials have found intact carcasses can be successfully thawed in cooler water but it takes longer. Australian Patent Application No. 2015101295, the contents of which are herein incorporated by way of reference, describes and compares a number of further methods of thawing an intact carcass. Table 2 below summarises a number of different thawing methods and their relative advantages and disadvantages.

Method of thawing a carcass

Cold

Hot Cold Hot water water

Some of the considerations water water One step Two to Cold with when thawing a carcass (>38°C) (<38°C) air step air water starch

Low potential for MMG

Very Not as Not as

formation on surface Excellent Excellent Excellent

Good good good

muscles

Low potential for excessive

Good Excellent Good Good Excellent Excellent growth of intestinal bacteria

Not as

good

unless

Not as Not as Not as energy is

Low energy cost Excellent Excellent good good good recovered

from

other

processes

Very Not as Not as Very

Time required for thawing Excellent Excellent

Good good good good

Freedom to vary thawing Very Not as Not as

Excellent Very good Excellent time Good good good

Suitability of meat

Not as Not as Not as

temperature for boning and Excellent Excellent Excellent good good good

packing when the carcass is thawed

Surface meat temperature

below 7 deg C when carcass

is ready to be dressed, e.g.

Not as Not as

skinned, to remove potential Excellent Good Excellent Excellent good good

for growth of mesophilic

pathogens during/after

dressing

Table 2 - Comparison of several methods for thawing an intact carcass

A concern that none of the thawing options previously identified fully address is the time taken to thaw intact carcasses so that the carcass can be eviscerated. When an intact carcass is thawed, the skin regains its elasticity quickly and consequently the hide can be removed from a carcass after a few minutes of thawing. However the gastrointestinal tract is the thickest part of a carcass and consequently may be the last part of an intact carcass to be thawed. If an intact carcass is not sufficiently thawed then it is difficult to separate the intestines from the backbone of the carcass and remove the viscera. Even the use of warm or hot water (e.g.

approximately 38°C) may take at least 5 hours to thaw an intact carcass to a stage where it can be eviscerated. Note that if water hotter than 38°C is used to thaw intact carcasses for more than a few minutes then the subcutaneous fat starts to cook, so this is undesirable. If a large number of carcasses were to be thawed in a commercial venture then very large water thawing baths/spray areas would be required, but this may not be a practical solution.

Note that the thorax is the same thickness as the abdomen and pelvis. However, because the thorax is designed to hold inflated lungs during life, there is a lot of empty space when the animal dies and the vacuum is penetrated, causing the lungs to collapse. Removal of the heart and lungs from an intact carcass is consequently possible, even when the carcass is still frozen.

The use of an elongate device such as has been described above inserted in the gastrointestinal tract of intact carcasses addresses at least some of these issues.

Figure 6 is a flow chart illustrating a method 600 of warming an animal carcass according to one embodiment of the invention. It will be understood that the steps of method 600 may be carried out as part of step 409 of the method of animal processing 400 described in relation to Figure 4, for example in addition to other steps of preparing the carcass for consumption.

At step 601, a cooled animal carcass is received. For example, the carcass may be frozen. In some embodiments the elongate cooling device used to cool or freeze the carcass has been removed, leaving behind a cavity having a similar shape to the cooling device.

At step 602 the received frozen carcass is tempered prior to thawing. For example, the carcass may be placed in a freezer operating at -2.5°C to -3.0°C for several days prior to

thawing/dressing. This means that the carcass can be held in a frozen/preserved state without any concerns about adverse organoleptic effects that can occur in a thawed carcass and the thawing process is sped up because the carcass does not have to warm up as much before it can be dressed. At step 603 a warming heat transfer medium is injected into gastrointestinal tract so that the heat transfer medium is in thermal contact with the carcass. In one embodiment, the heat transfer medium is injected directly into the cavity in the carcass left behind by the cooling device. In one embodiment of the invention, the warming heat transfer medium is water at a temperature of approximately 50°C. However it will be understood that the heat transfer medium may be any fluid able to convey heat to the carcass and may include, for example, brine. Furthermore, the heat transfer medium may be at any temperature able to warm or thaw the carcass. Typically, the warming heat transfer medium has a temperature in excess of 0°C and more preferably at least ambient temperature, and more preferably at least 38°C, In one embodiment, water is injected into the cavity in the colon of the carcass by immersing the carcass in water. The act of immersing the carcass in water will be understood to cause water to be injected into the colon cavity.

In an alternative embodiment, the step of injecting the heat transfer medium into the gastrointestinal tract comprises injecting the heat transfer medium into an elongate device that is positioned inside the gastrointestinal tract. For example, the animal carcass may already have an elongate colon device inserted in it that is left in place from the cooling method described above. Alternatively, a different elongate colon device may be inserted into the colon for the step of warming the carcass. Inserting the elongate device into the carcass when the carcass is frozen may be difficult if the colon device is the same size as the cavity in the colon formed by the cooling device. The elongate colon device may therefore be pre-filled with warm or hot water to facilitate the insertion. Alternatively, the elongate colon device used for facilitating warming of the carcass may be slightly smaller than the elongate device used for cooling the carcass, and therefore slightly smaller than the cavity into which it is inserted. In a still further embodiment of the invention, heat is supplied to the gastrointestinal tract of the carcass by an alternative heating device. For example, in one embodiment, an elongate colon warming device may be provided that can be inserted into the cavity in the colon formed by the cooling elongate device described above. In this embodiment, the elongate colon warming device may generate heat using electricity, for example it may contain resistive heating elements inside it.

At step 604 the carcass is eviscerated. The step of supplying heat to the frozen colon of the carcass at step 603 warms the tissue surrounding the colon and enables them to be pulled away from the backbone, making evisceration easier. This step is also helped by the use of the elongate cooling device when freezing the carcass. Insertion of the cooling device into the colon pushes the intestines away from the backbone slightly so that, when the carcass freezes, the intestines do not freeze firmly against the backbone.

Figures 7, 8 and 9 are graphs illustrating data captured from an intact carcass (carcass ID 17/3) when thawed having been frozen while using a colon cooling device such as described with reference to Figure 2. The colon cooling device was 500mm long with an internal diameter of 25mm and an outside diameter of 30mm. The colon cooling device was immediately removed following freezing. The carcass was tempered prior to thawing so that the abdominal temperature immediately prior to thawing was ~3.0°C. The carcass was thawed by immersing it in water at approximately 50°C for five minutes. The entire carcass was immersed in the water, including the anus so that the colon (distended from application of the colon tube prior to freezing) filled with water.

Figure 7 is a graph 70 showing the temperature of the water in which the carcass was immersed over the time that the carcass thawed.

Figure 8 is a graph 80 showing the temperature of the water inside the colon of intact carcass ID 17/3 over the time the carcass thawed and during the start of dressing the carcass. The temperature logger was positioned in the distended part of the colon where the colon cooling device had been inserted to freeze the carcass. This was the part of the colon furthest from the anus during thawing. Marker 81 indicates the time at which the carcass was placed in the water bath and marker 82 indicates the time the carcass was removed from the water bath.

Figure 9 is a graph 90 showing the temperature of the abdomen of intact carcass ID 17/3 prior to, and during thawing, and up to the point of evisceration. Marker 91 indicates the time at which the carcass was placed in the water bath and marker 92 indicates the time the carcass was removed from the water bath.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to".

The entire disclosures of all applications, patents and publications cited above and below, if any, are herein incorporated by reference.

Reference to any prior art in this specification is not, and should not be taken as, an

acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in the field of endeavour in any country in the world. The invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features. Where in the foregoing description reference has been made to integers or components having known equivalents thereof, those integers are herein incorporated as if individually set forth.

It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be included within the present invention.