GB2317323A

GB2317323A - Slow speed removal of animal hides

Info

Publication number: GB2317323A
Application number: GB9719762A
Authority: GB
Inventors: Harry Schulz
Original assignee: AUSTRALIAN MEAT TECHNOLOGY Pty
Current assignee: AUSTRALIAN MEAT TECHNOLOGY Pty
Priority date: 1996-09-18
Filing date: 1997-09-16
Publication date: 1998-03-25
Anticipated expiration: 2017-09-16
Also published as: NZ328777A; AUPO245296A0; GB9719762D0; GB2317323B

Abstract

The invention relates to a process for removing a hide from the carcass of an ovine animal comprising the steps of suspending the carcass by the hind legs; clearing the pelt from the hind legs, tail, and rump; engaging a portion of the pelt that has been cleared from the carcass; and pulling the engaged proportion of the pelt downwards with a force sufficient to strip the pelt from the carcass. The speed at which the pelt is stripped from the carcass is sufficiently slow to reduce grain strain of the pelt and/or blood spotting of the carcass, e.g. taking 30 or more seconds to remove the pelt. Little or no preliminary dressing of the forequarter is performed. The pulling may be carried out by clamping the hide between two fingers which are then rotated and moved such that the hide is wound around the fingers as it is pulled from the carcass.

Description

ANIMAL PELT REMOVAL This invention relates to the removal of the pelt from a slaughtered animal. The invention is particularly suitable for ovine animals and the expression "ovine animal" is intended to cover sheep and goats and animals with similar pelts. However the process and apparatus can be used on calves, although it is not expected the invention will be used for grown cattle where the problems which the present invention addresses do not exist or are of lesser concern.

Presently there are two common processes for removing pelts of slaughtered ovine animals which we will refer to as the "conventional dressing system" and the "inverted dressing system" The conventional dressing system involves preliminary operations with which the present invention is not concerned, particularly the stunning of the animal to be slaughtered, followed by sticking and oesophagus occlusion. In the conventional dressing system, the carcass is then hung from one or both hind legs, followed by the steps of: (i) skinning of the two hind legs to clear the pelt ready for removal; (ii) skinning of the flanks at both sides of the carcass preparatory to pelt removal; (iii) skinning of the tail and pulling of the pelt down past the chumps (the lumbar region of the back under the hind legs); (iv) elevation of the front legs into an A-frame/spreader with the toes/hooves of the front legs wedged into the spreader forks which are approximately 400mm apart preparatory to forequarter dressing; (v) forequarter skinning which involves clearing the pelt from the fore legs and neck preparatory to pulling the pelt from the carcass; (vi) releasing of the front legs from the spreaders so as to leave the carcass hanging by its hind legs; (vii) removing the pelt manually by punching a clenched fist down one side of the carcass between the pelt and the flesh, thereby creating a pocket; (viii) manually grasping the pelt with both hands at the area of the pelt which covered the hind legs but which had been cleared therefrom in step (i); (ix) pulling the pelt away from the carcass manually by the operator moving backwardly, pulling with considerable force so as to pull the pelt from the elevated hind legs and rump area to the head end of the carcass.

This substantially manual operation is quite labour intensive, thus adding significantly to the processing costs. There are also potential hygiene difficulties particularly associated with the use of the A-frame/spreader. For example, it is difficult at times to prevent wool side of the skin from contacting the exposed meat thereby causing contamination of the carcass. This difficulty arises because the animal on the A-frame is at an angle, making it difficult to maintain full control during pelt removal.

The inverted dressing system uses substantially the same first five steps (i) to (v) as described above. However, with the inverted dressing system, the following steps then occur: (vi) the back legs are released from their shackles or other supports by which the carcass was suspended, thereby leaving the carcass suspended by the front legs by the A-frame/spreaders; (vii) the pelt, where it has been cleared from the front legs, is clasped by a mechanical pulling apparatus and the pelt is pulled from the shoulder area of the carcass; (viii) the pelt is then cleared from the belly region of the carcass; and (ix) the pulling of the pelt by mechanical means is then resumed with the pull direction being from the head end towards the rump end until the pelt is entirely removed from the carcass.

This inverted dressing system can lead to significant deterioration of product quality by hind quarter blood spotting and/or pelt grain strain. Blood spotting on the back legs is a result of the blood vessels rupturing during the pelt pulling in the inverted dressing system configuration. Grain strain is damage to the grain layer of the pelt (i.e. the wool-side of the skin) due to damage to the layers of skin. This grain strain occurs during the mechanical pulling with the carcass in the inverted position (head up and rump down). Grain strain to a pelt substantially destroys the value of the pelt for further processing into leather garments particularly and this kind of damage very substantially affects the profitability of the ovine animal industry.

In spite of the substantial adverse effects of the inverted dressing system, that system is widely used because it is capable of processing ovine animal carcasses at a rapid rate, e.g. in the order of 6 to 8 carcasses per minute which are processing speeds commonly required.

The inverted dressing system also involves very substantial labour costs in the manual parts of the process. Typically four operators are required to carry out the necessary manual operations within one minute. Thus, if the abattoir line speed is 5 carcasses per minute, 20 operators are required to be continuously working in the dressing and pelt removal stage of the process.

It is an object of the present invention to provide a process for removing a pelt from the carcass of an animal which can alleviate at least one of the drawbacks of the present dressing processes outlined above.

It is a preferred object of the present invention to provide a process for removing a pelt from the carcass of an animal which can enable a reduction in the manual labour required for the process.

It is a further preferred object to provide a process for removing a pelt from the carcass of an animal with a substantial reduction in risk of hind quarter blood spotting damage to the carcass and/or pelt grain strain damage to the pelt.

The process for removing a hide from the carcass of an animal according to the present invention comprises the steps of: suspending the carcass of the animal by the hind leg(s); dressing the carcass to clear the pelt from the hind legs, tail, and rump; engaging a portion of the pelt that has been cleared from the carcass; and pulling the engaged portion of the pelt in a downwards direction with a force sufficient to strip the pelt from the carcass the speed at which the pelt is stripped from the carcass being sufficiently slow to reduce grain strain of the pelt and/or blood spotting of the carcass.

By pulling the pelt downwardly, i.e. in the direction from the rump end towards the head end at a slow speed, it has been found that grain strain and blood spotting can be substantially reduced or eliminated particularly in ovine animals for which the invention has been particularly developed.

The speed at which the pelt is removed can be empirically determined but is preferably at a speed to remove the pelt in a period of time greater than 20 seconds, and more preferably greater than 30 seconds. The pelt removal time, for example, may be in the range of 50 to 90 seconds. Removal in less than 20 seconds approaches the speeds of the prior art with carcass and/or pelt damage. Speeds greater than 90 seconds can have serious economic disadvantages in an abbatoir.

Because of the relatively long time for removal of a pelt according to the process of the present invention, a carcass process line utilising the present invention preferably is operated to have multiple carcasses all having their respective pelts removed simultaneously so that the overall production throughput of the line can be equal, for example, to the present inverted processing system in which carcasses are presented sequentially to the pelt remover and which operates to completely remove the pelt from the carcass in less than 10 seconds (if for example 6 to 8 carcasses per minute are being processed). For example, in a processing line using the present invention, pelts of successive carcasses being processed may be at different stages of removal at any one instant. This may be achieved by providing a progressing system into which each carcass enters at the end of the preliminary dressing stages so that the pelt pulling proceeds as the carcass passes through the progressing system through which other carcasses are simultaneously passing and having their pelts removed.

Thus carcasses which have had their pelts removed at slow speeds can nevertheless be emerging from the progressing system at whatever the rate of introduction is, e.g. 6 to 8 carcasses per minute.

In a possible working system, the carcass processing line may advance carcasses suspended from their hind legs along a generally linear path and, at the pelt removal station, the progressing system comprises multiple clamping means, each clamping means being for clamping the hide of a respective carcass by the portion of the hide which has been separated from the carcass in a preliminary hind quarter dressing operation. In this system, the process includes the step of advancing the clamping means along the linear path together with the respective carcass and simultaneously moving the clamping means downwardly so as to slowly pull the hide downwardly to separate it from the carcass.

In a preferred embodiment, each clamping means comprises two clamping fingers which clamp the portion of the hide cleared during the preliminary hind quarter dressing operation, the process further including the step of rotating the clamping fingers simultaneously with being moved downwardly whereby the hide is wound around the clamping fingers as it is being pulled from the carcass.

The principle or concept of slow speed pulling of each pelt from the carcass represents a major departure from the present accepted principles of ovine animal carcass processing.

The preliminary steps of stunning, sticking and occluding the oesophagus can be conventional operations. The preliminary dressing operations leading up to the engagement and pulling of the pelt may be substantially the same as steps (i) to (iii) as outlined above.

However, preferably according to the present invention, there is no preliminary dressing of the forequarter, i.e. no preliminary clearing of the pelt from the front legs, neck and head region prior to pulling of the pelt from the carcass. However, some opening of the pelt, e.g.

separation of the pelt from the brisket and/or opening of the socks, may be desirable on different lots. It has been surprisingly found that the slow pulling of the pelt from the elevated rump end to the head end can pull the pelt completely from the carcass without the need for forequarter dressing. It is found that the pelt can peel off the fore legs so that the pelt everts in peeling off the fore legs. This elimination or minimising of the forequarter dressing also represents a major departure from the conventional processing systems and is surprisingly effective in conjunction with the slow speed pulling of the pelt, thus eliminating entirely some manual operations presently considered essential.

After removal of the pelt from the carcass, the carcass can then undergo subsequent processing operations which can be substantially conventional such as bung removal and evisceration operations.

Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention. In the drawings: Fig. 1 is a schematic side view of an apparatus useable in the present invention, and Fig. 2 is a plan view of a hide removal station using the apparatus of Fig. 1.

Fig. 1 shows multiple carcasses 10 which are being continuously advanced from left to right by an overhead conveyor system 11 which may be of generally conventional type. The carcasses 10 as shown are suspended from their hind legs. The carcasses 10 when arriving at the hide removal station 12 have already undergone preliminary hind quarter dressing operations of the kind described earlier in this specification, thus leaving portions of the hide cleared from the hind legs available to be grasped and pulled downwardly. As shown in Fig.

2 particularly, the carcasses 10 are advanced along a generally linear path by the conveyor system 11 although the carcasses can be sequentially introduced from a lateral direction as shown by the carcass 10a about to be introduced to the hide removal station 12. This enables hide pulling apparatus 15 to be brought into position behind the carcass 1 0b which has just entered the hide removal station 12.

The hide pulling apparatus 15 comprises hide clamping means 16 which is mounted by a carriage 17 movable vertically on a post 18. The apparatus 15 moves along parallel to the linear path of movement of the carcasses 10 during the hide removal operation and, as shown in Fig. 2, the apparatus 15 can thereafter be moved away from the path of the carcass movement enabling recovery of the removed hide and cleaning of the apparatus 15 prior to reuse on a subsequently introduced carcass.

The hide clamping means 16 comprises two clamping fingers 20 which project generally horizontally and between which a portion of the hide removed during the preliminary hind quarter dressing operations is received. The clamping fingers 20 then move together to clamp that portion of the hide. The carriage 17 is then slowly driven by any suitable drive down the post 18 thereby progressively pulling the hide downwardly to pull it from the carcass. Simultaneously with downward movement of the carriage 17, the clamping fingers 20 can be rotated about the horizontal axis 21 which is located between the clamping fingers 20, the rotation being effected by a motor 22 for example. By rotating the clamping fingers 20 about the axis 21 simultaneously with downward movement of the carriage 17, the hide as it is being removed from the carcass is wound around the clamping fingers 20. This can conserve the space particularly the height needed and also can enable the hide clamping means 16 to help stabilise the carcass 10 against swaying movement during the hide pulling operation.

The process of removing the pelt according to the present invention as described above can be further understood by referring to the apparatus embodiment illustrated in the drawings.

The process of the present invention by providing a slow gentle downward pull of the pelt can significantly reduce or eliminate blood spotting damage to the carcass. The slow gentle pull also significantly reduces or eliminates grain strain damage to the grain layer of the pelt thus yielding a significantly improved pelt in quality and hence value. The potential for elimination of at least some manual operations, particularly at least some of the forequarter dressing operations, can enable significant reductions in the labour costs of processing of animal carcasses, particularly ovine animal carcasses.

It is to be understood that various alterations, modifications and/or additions may be made to the features of the possible and preferred embodiment(s) of the invention as herein described without departing from the scope of the invention as defined in the claims.

Claims

1. A process for removing a hide from the carcass of an animal comprising the steps of:

suspending the carcass of the animal by the hind leg(s); dressing the carcass to clear the pelt from the hind legs, tail, and rump; engaging a portion of the pelt that has been cleared from the carcass; and pulling the engaged proportion of the pelt in a downwards direction with a force sufficient to strip the pelt from the carcass, the speed at which the pelt is stripped from the carcass being sufficiently slow to reduce grain strain of the pelt and/or blood spotting of the carcass.

2. A process as claimed in claim 1 wherein the carcass is the carcass of an ovine animal.

3. A process as claimed in claim 1 or 2 wherein the pelt is stripped from the carcass at a speed to remove the pelt from the carcass in a period of time greater than 20 seconds.

4. A process as claimed in claim 3 wherein the pelt is stripped from the carcass at a speed to remove the pelt from the carcass in a period of time greater than 30 seconds.

5. A process as claimed in claim 4 wherein the pelt is stripped from the carcass at a speed to remove the pelt from the carcass in a period of time between 50 and 90 seconds.

6. A process as claimed in any one of the preceding claims wherein the process is carried out as part of a carcass processing line in which successive carcasses are presented to a pelt removal station at time intervals less than the time for removal of each pelt from the associated carcass, the pelt removal station including a progressing system for accommodating multiple carcasses so that their respective pelts are being simultaneously removed and in which the pelts of successive carcasses being processed in the progressing system are at different stages of removal at any one instant.

7. A process as claimed in claim 6 wherein the carcass processing line advances carcasses suspended from their hind legs along a generally linear path and at the pelt removal station the progressing system comprises multiple clamping means, each clamping means being for clamping the hide of a respective carcass by the portion of the hide which has been separated from the carcass in a preliminary hind quarter dressing operation, the process including the step of advancing the clamping means along the linear path together with the respective carcass and simultaneously moving the clamping means downwardly so as to slowly pull the hide downwardly to separate it from the carcass.

8. A process as claimed in claim 7 wherein each clamping means comprises two clamping fingers which clamp the portion of the hide cleared during the preliminary hind quarter dressing operation, the process further including the step of rotating the clamping fingers simultaneously with being moved downwardly whereby the hide is wound around the clamping fingers as it is being pulled from the carcass.

9. A process as claimed in any one of the preceding claims wherein there is no preliminary dressing of the forequarter in the nature of preliminary clearing of the pelt from the front legs, neck and head region prior to pulling of the pelt from the carcass.

10. A process as claimed in any one of claims 1 to 8 wherein there is preliminary dressing of the forequarter in the nature of separation of the pelt from the brisket and/or opening of the socks, but no other preliminary clearing of the pelt from the front legs, neck and head region prior to pulling of the pelt from the carcass.

11. A process for removing a hide from the carcass of an animal substantially as hereinbefore described with particular reference to the accompanying drawings.

12. An apparatus for removing a hide from the carcass of an animal substantially as hereinbefore described with particular reference to the accompanying drawings.