4 COMPARISON OF BEEF AND YEAST EXTRACTS. 



DISCUSSION OF ANALYTICAL DATA. 



The samples, which were carefully stoppered and kept in an ice 

 chest after arriving at the laboratory, were analyzed with the results 

 reported in Table 1. 



TABLE 1. Comparative analysis of beef and yeast extracts. 



ON BASIS OF ORIGINAL SAMPLE. 



CALCULATED TO A MOISTURE-FREE AND FAT-FREE BASIS. 



a This figure includes about 25 per cent of the total kreatin and kreatinin nitrogen. 

 & Expressed as cubic centimeters of tenth-normal sodium hydroxid per gram. 



The ash results are lower for the beef than for the yeast extracts 

 with one exception, A. P. 794, giving practically the same figures 

 as the yeast extract, A. P. 725. The chlorin content of the ash, cal- 

 culated as sodium chlorid, is practically the same in the two kinds 

 of extracts. The total phosphoric acid, that in the ash, and the 

 organic phosphoric acid are also practically identical on the moist 

 basis. The ether extract and all of the nitrogen figures for the beef 

 extracts are considerably higher than those for the yeast prepara- 

 tions. The chief difference, which has been noted by many observers, 

 is the absence of kreatin and kreatinin in the yeast extracts. While 

 amounts of these two bodies present in the beef extracts are subject 



