45 



marked. A slight od>r <>f spoiled meat was noticeable, more markedly in the fresh 

 ainl -tored meat than in thr preserved. After standing si\ days the odor was quite 

 |>ad; thr samples had lost their texture and there was no doubt that they had spoiled. 

 NO .Inference in their physical condition could be detected after standing seven days 

 thai ua.- M"t noticeable after six days standing. 



The nitrogen determined in the water-soluble material at room temperature shows 

 the total nitrogen extra-ted to be largely increased during the experiment, the first 

 decided :ncrea.-e shouin- in the <amples after standing two days. The coagulable 

 nitrogen sho\\s l>ut a slight tendency to increase, the most marked and uniform change 

 red -ample. The amido nitrogen is not very uniform and shows a 

 tendency to d- 'ially where the samples are in an advanced stage of putre- 



M. The nitrogen liere termed proteoses and peptones is markedly increased 

 during the final days of the experiment, the storage sample again showing a more uni- 

 form chaiiL'e. Tin- increase of ammonia nitrogen in the water extract conforms to that 

 determined directly, but is not quite .-<> lar-e in amount. 



The nitrogen in the ice \\atT extract in the various forms separated shows the same 

 .il trend as does that of the room temperat'ure extract, though the amounts 



.-ually not so large. 



The graphic char' nd -t, -how these changes more plainly. It is quite 



noticeable throughout that the re-ults on the storage sample are very uniform and 



i. in all but two instance.-, in all the determinations, the 



results on the fin( anal\-i- -ho\\ the .-lora-' 1 .-ample to be lower in the various con- 

 iii.- than I he fresh sample-. The same -oneral tendency seems to run through- 

 nut tli" experiment though one would expect the storage meat to deteriorate more 

 rapidly. 



Taking into ,.>n the variations in the determinations and the limitations 



of tin- ineiliud- ih.'in-. 1\ .-. there does not appear to he a very clearly denned point 



M h deterioration .an be -aid to be-in, unless it is shown by the ammonia and 



ible total nitrogen determinations. The increase in these constituents coin- 



witli thei, ..itionand physical appearance of the sample. The 



in the extraction is unnecessiry, as the methods employed are not of 



:ent accuracy ! detect the -n-ater rhanges from day to day in the early stages, 



much lees any change which may be due to enzymic action during the process of 



Lion. 



It seems probable from the results that the determination of ammonia may be a 

 i-.-et in shouii. t indication* of changes, as these results are the 



uniform and progressive. A large amount of work has recently been done on 

 the methods for the determination of ammonia in animal and vegetable materials, 

 irdson a: perimenting on the ammonia nitrogen determina- 



tion, and in which he extracted the meat with GO per cent alcohol and distilled with 

 ,-piratinu' air through the flask, and distilling under reduced pres- 

 sure, finally adopted the method as outlined above as best suited to the purpose. 



Hi- re-ult- on pure ammonium chlorid distilled in a vacuum with magnesium oxid 

 and io per .cut alcohol are nearly theoretical. This is in substance the method as 

 : in the determination of ammonia in urine and might be adapted to 

 thi.- u.. r k 



J. Amer. Them. Soc., 1908, 30: 1515. 



