1913] Clayfon S. Smith 65 



sodium hydroxid for sodium carbonate. After a long series of 

 experiments, Pennington and Greenlee found that the results ob- 

 tained with the modified Folin method agreed very well with those 

 obtained when the older magnesium oxid method was used. By 

 using sodium hydroxid we were open to the criticism that our 

 results might be higher than actual ammonium values. Yet granting 

 this possibility, we found that the proportionof ammonium nitrogen 

 was very low, even after a nine months' period of storage. If, 

 therefore, by using a method which might give high results, no in- 

 crease in ammonium nitrogen was found, after six months of storage 

 and only a trivial increase after nine months of storage, it is fair 

 to conclude that the fish were practically unchanged at the end of 

 the last named period of storage. [See the preceding paper by 

 Shulansky and Gies (p. 45) and the succeeding one by Perlzweig 

 and Gies (p. 69).] 



Pennington and Greenlee found the ammonium nitrogen content 

 of fresh chicken meat to be 0.012 per cent. Houghton^'^ reports 

 0.021 per Cent, of ammonium nitrogen in fresh light chicken meat 

 and 0.039 P^^ Cent, in the same kind of meat after a period of five 

 months of storage. For dark chicken meat he reports 0.019 P^^ 

 cent. ammonium nitrogen in the fresh sample and 0.026 per cent. 

 after a period of five months of storage. It would appear, then, 

 that so far as the production of ammonium nitrogen is concerned, 

 fish in cold-storage change more slowly than chickens. 



Total nitrogen. Unless some ammonia was formed in the fish, 

 and escaped into the air, there would be no chance for any diminu- 

 tion in the nitrogen content. Total nitrogen remained unchanged. 

 It will be noticed that there is a diflference of about i per cent. be- 

 tween the nitrogen content of flukes and flounders, This Variation 

 is partly explained when one takes into consideration the difference 

 in Contents of water. 



" Soluble nitrogen." If any hydrolytic changes took place 

 during the cold-storage period it would be natural to suppose that 

 one or more of the nitrogenous constituents of the muscle became 

 more soluble, or, in other words, that there was an increase in the 

 "soluble nitrogen." Our results indicate that there was no in- 



i'^Houghton: /. Ind. Eng. Chem., 191 1, iii, p. 497. 



