464 POULTRY PRODUCTION 



Singeing is not practised when dressing for future con- 

 sumption, because it tends to soften the skin and injure 

 the keei)ing quaHties 



Precooling. — It is absolutely necessary that animal heat 

 be allowed to pass out of a dressed bird as soon as pos- 

 sible after it is killed. Bacterial action begins at once. 

 While cooling does not entirely stop it, it does greatly retard 

 it. There are two methods of cooling — dry and wet. When 

 dry cooling is employed, the carcass is simply placed in cold 

 air until the animal heat has all escaped. While it is the 

 common practice to freeze poultry that is to be held any 

 time, care must be taken that freezing does not occur during 

 the cooling process. If it does occur the carcass will not cool 

 out properly. The reason for this is that freezing hardens 

 the outside of the carcass, causing it to act as insulation. 

 And further, it congeals the moisture near the surface and 

 stops the flow of the juices of the body. The juices of the 

 bird continue to flow from one part of the body to another 

 for a considerable time after the bird is killed, especially if 

 one part of the body is colder than another. This affords an 

 op]3ortunity for the internal animal heat to escape at the 

 surfare. It is well known among practical packers that with 

 a birtl placed in too cold a temperature immediately after 

 dressing, the heat is held within long enough to ^We the 

 putrefacti^'e bacteria a chance to develop to a sufficient 

 extent to give the bird an oft'ensive flavor when cooked. 



The best cooling temperature is between 30° and 35° F. 

 To determine when a carcass is cool enough for freezing, 

 insert a small stemmed thermometer into the vent. It should 

 show a temperature of not more than 35° F. The time 

 necessary for cooling will vary with the size of the carcass. 



Wet cooling is frequently resorted to. As soon as the fowl 

 is dressed it is plunged into ice-water. This removes the heat 

 ell'cctively, but Pennington^ has found that 4 per cent, of 

 the protein in chicken flesh will dissolve out in an hour. For 

 e\ery ounce of protein dissolved 4.3 ounces of water are 

 absorlied. The practice is to be discouraged, and is coming 



1 Addresa before Missouri Carlot Shippers of Poultry, Kansas Caty 1912. 



