DISCUSSION OF THE PRIOR ART
During the slaughter of poultry, the birds are in succession stunned, bled, scalded (immersed in hot water for several minutes), plucked and eviscerated (removal of the viscera), following which the birds are sprayed with a cleaning liquid, not only on the outside, but also on the inside, in order to flush the carcass and the meat clean.
A washer for internal cleaning of poultry generally comprises a spraying element in which apertures are provided for spraying on virtually all sides, said spraying element being fitted on one end of a tube through which cleaning liquid can be supplied to the spraying element.
If the birds are being processed in a mechanized slaughterhouse, in which they are conveyed hanging by the legs through various processing stations, during the washing the washer is moved vertically downwards through the opening formed between the legs during eviscerating. When the spraying element is inside the bird, cleaning liquid is fed into it, so that the inside of the bird is washed. The liquid fed into the bird in this way leaves the body cavity through the neck opening obtained in preceding operations.
A source of problems in the cleaning is formed by the membranes left behind after eviscerating, i.e. air sacs and other membranes. The air sacs, which form part of the respiratory system, normally lie against the inside wall of the body cavity. After eviscerating, the membranes (in the earlier indicated vertical position of the birds) hang in the region of the neck, and can thereby impede the discharge of polluted cleaning liquid. There is also the chance of the membranes filling up with polluted cleaning liquid during washing, which then contaminates the body cavity for a longer period and is taken to further processing stations where it may cause contamination.