MARKET COLD-STORAGE CHICKENS. 63 



The skin, with the adhering subcutaneous fat, was mixed with the 

 fat separated from the viscera and the abdominal cavity and that 

 stripped off of the muscles, ground in the meat cutter until fine, and 

 used for the study of the fat of the fowl. 



MUSCLE DETERMINATIONS. 



The general analysis of the muscle was based on the determina- 

 tion of water, fat, ash, total nitrogen, and total solids. The nitrog- 

 enous portion was further investigated for the nitrogen soluble in 

 water, and in this aqueous extract was determined the coagulable ni- 

 trogen, albumose nitrogen, and amido acid nitrogen, the peptone nitro- 

 gen and the nitrogen insoluble in water being found by difference. 



For the determination of the total solids, water, fat, and ash in 

 the muscle, a homogeneous well-mixed sample of the meat was 

 weighed in a tightly stoppered weighing bottle, and portions, of 

 approximately 10 grams each, were transferred to appropriate con- 

 tainers, as desired. 



TOTAL SOLIDS AND WATER. 



For the total solids and water a 10-gram portion was dried at 

 100 C. in a tared lead bottle cap from 2 to 3 inches in diameter. 

 It being practically impossible to dry a sample of such material as 

 chicken meat to constant weight, because of the oxidation of the 

 substance after the removal of the last traces of water, the sample 

 was reweighed at short intervals and a gain in weight taken as an 

 indication of the absence of moisture. This gain was ordinarily not 

 more than a few tenths of a milligram. Occasionally, however, it 

 was several milligrams. 



FAT. 



The quantity of fat in the muscle material itself was found by 

 extracting the dry residue from the water and total solids determi- 

 nation with Squibb's ether. This was readily accomplished by cut- 

 ting up the lead cap, with its contents, into small pieces and placing 

 the mixture in the thimble of a Knorr extractor, which was then, 

 with the requisite amount of ether, heated for 16 hours on an elec- 

 tric heater. When the extraction was completed, the ether was 

 evaporated and the fat dried at 100 C. until the moisture was 

 removed, which was indicated by a slight gain in weight, as in the 

 case of the total solids. The weighings here were at intervals of 

 from 2 to 3 hours. 



ASH. 



For the determination of the amount of ash two or three grams 

 of the sample were dried in a platinum crucible, then heated in a 

 muffle until completely charred, allowed to cool, and extracted sev- 



