Method and apparatus for preparing poultry carcasses for defeathering operations
A process includes contacting a feathered poultry carcass with an ammonia-based treatment material to increase the pH at the skin of the carcass and thereby effect a loosening of the feathers on the carcass. After the contact with the ammonia-based treatment material, mild heat may be applied to the feathered carcass to further loosen the feathers. The prepared feathered carcass is then defeathered in a suitable defeathering process. Ammonia may be removed from the carcass before, after, and/or during defeathering. The defeathered carcass is then passed on for further processing to produce the final poultry product.
1. A method of treating a feathered poultry carcass, the method including:
(a) placing the poultry carcass in contact with an ammonia-based treatment material to modify the pH at the skin of the poultry carcass, wherein the ammonia-based treatment material is a pH increasing material and wherein the pH modification at the skin of the poultry carcass is a pH increase; and
(b) removing ammonia from the poultry carcass after placing the poultry carcass in contact with the ammonia-based treatment material.
2. The method of claim 1 wherein placing the poultry carcass in contact with the ammonia-based treatment material increases the pH at the skin of the poultry carcass by no less than one-half (0.5) point on the pH scale.
3. The method of claim 1 wherein the removal of ammonia from the poultry carcass is performed as a separate step after initiating defeathering of the poultry carcass.
4. The method of claim 1 wherein the step of removing ammonia from the poultry carcass is initiated prior to initiating defeathering of the poultry carcass.
5. The method of claim 1 further including initiating defeathering of the poultry carcass after placing the poultry carcass in contact with the ammonia-based treatment material and without contacting the poultry carcass with a scald material.
6. The method of claim 1 :
(a) wherein removing ammonia from the poultry carcass includes at least immersing the poultry carcass in water after placing the poultry carcass in contact with the ammonia-based treatment material, the water being held at a temperature of no more than 110° F.; and
(b) initiating defeathering on the poultry carcass after immersing the poultry carcass in the water and after removing the poultry carcass from the water.
7. The method of claim 1 wherein removing ammonia from the poultry carcass includes applying a rinsing liquid to the poultry carcass.
8. The method of claim 7 wherein the temperature of the rinsing liquid is no more than 110° F.
9. The method of claim 1 further including recovering ammonia from the poultry carcass during a defeathering operation for the poultry carcass.
10. The method of claim 1 wherein the ammonia-based treatment material includes liquid ammonia.
11. The method of claim 10 wherein the liquid ammonia is contained in an immersion vessel and the poultry carcass is placed in contact with the liquid ammonia by immersing the poultry carcass in the liquid ammonia contained in the immersion vessel.
12. The method of claim 11 wherein the poultry carcass is immersed in the liquid ammonia for no less than approximately 2 seconds.
13. The method of claim 10 wherein the liquid ammonia is sprayed on to the poultry carcass.
14. The method of claim 1 wherein the ammonia-based treatment material includes gaseous ammonia.
15. The method of claim 1 wherein the ammonia-based treatment material includes an ammonium hydroxide solution.
16. The method of claim 15 wherein the ammonium hydroxide solution is contained in an immersion vessel and the poultry carcass is placed in contact with the ammonium hydroxide solution by immersing the poultry carcass in the ammonium hydroxide solution contained in the immersion vessel.
17. The method of claim 15 wherein the poultry carcass is placed in contact with the ammonium hydroxide solution by spraying the ammonium hydroxide solution on to the poultry carcass.
18. The method of claim 15 wherein the ammonium hydroxide solution is at a temperature of no more than −45° F. when it is initially placed in contact with the poultry carcass.
19. An apparatus including:
(a) a treatment material supply;
(b) a contacting device connected to receive an ammonia-based treatment material from the treatment material supply, the contacting device for placing the ammonia-based treatment material in contact with a feathered poultry carcass, the ammonia-based treatment material comprising a pH increasing material which is effective to produce a pH increase at the skin of the feathered poultry carcass;
(c) a poultry carcass defeathering device;
(d) an ammonia removal device for receiving the feathered poultry carcass after having been placed in contact with the ammonia-based treatment material by the contacting device, and for removing ammonia from the feathered poultry carcass; and
(e) a conveying system for conveying the feathered poultry carcass from the contacting device to the poultry carcass defeathering device and ammonia removal device.
20. The apparatus of claim 19 further including an ammonia vapor collection system connected to receive ammonia gas from at least the ammonia removal device and to separate the received ammonia gas from one or more other gasses mixed with the ammonia gas.
21. The apparatus of claim 19 further including a feather collection device for removing feathers from the poultry carcass defeathering device and recovering ammonia from the feathers.
22. A method of treating a feathered poultry carcass, the method including:
(a) placing the poultry carcass in contact with an ammonia-based treatment material to modify the pH at the skin of tile poultry carcass, wherein placing the poultry carcass in contact with the ammonia-based treatment material increases the pH at the skin of the poultry carcass by no less than one-half (0.5) point on the pH scale; and
(b) removing ammonia from the poultry carcass after placing the poultry carcass in contact with the ammonia-based treatment material.