62 PRELIMINARY COLD STORAGE STUDIES. 



The history of the cold-storage chickens is unknown up to the 

 beginning of storage, the date of which is known. They were first 

 placed in a cold freezer having a temperature of from 4 to 6 F. 

 until solidly frozen, which requires about 48 hours; then they were 

 transferred to a temperature of approximately 13 F. All of the 

 market cold-storage chickens reported at this time have been treated 

 similarly. They were removed from the warehouse about 24 hours 

 before the analysis was begun and were allowed to thaw at the tem- 

 perature of an ice box. Occasionally, especially in the case of large 

 birds, there would be enough ice in the tissues when .the examina- 

 tion was begun to cause the knife to grit, but usually they were 

 simply very cold to the touch. 



One chicken only No. 69, in storage two years was thawed in 

 the usual commercial fashion, namely, by soaking in cold water. 

 Since such treatment prevents any accurate idea of the bacterial 

 content of the flesh itself, and as a bacterial, a histological, and a 

 chemical examination of each fowl was desired, dry thawing was 

 adopted. Such a procedure gave a greater proportion of solid mat- 

 ter in the flesh than was obtained in either the fresh or the soaked 

 chickens, because of the marked drying of the tissues while in storage. 



CHEMICAL TECHNIQUE. 



The methods of chemical analysis employed were, as nearly as 

 possible, those officially recommended and commonly used in flesh 

 analysis. A brief outline of the procedure followed is given. The 

 chemical analyses were made by J. S. Hepburn and John I. Burrell. 



PREPARATION or SAMPLE. 



When the birds were large enough, only one was used for analysis. 

 When small, two were used, care being taken to thoroughly mix the 

 tissue. 



The flesh of the chicken was prepared for analysis by separating 

 it from the bones and the skin, removing as completely as possible 

 the fat between the muscles and also the large tendons, which in the 

 leg and wing muscles of the chicken are easily stripped loose from 

 the meat. Their absence is a factor too small to influence analyt- 

 ical results, but their presence renders the grinding and accurate 

 sampling of the meat more difficult. The muscles of the thighs and 

 legs were classed as dark meat, of the breast and upper wings as 

 light meat. The dark and light portions were put separately through 

 a meat grinder until the particles were very finely divided, which 

 necessitated ordinarily three grindings. It was found undesirable to 

 grind the flesh too finely, since the shaking required for the extrac- 

 tion of the soluble material caused an emulsion which it was practi- 

 cally impossible to filter. 



