New YorK AGRICULTURAL EXPERIMENT STATION. BLY 
In Normal Cheese. In Cheese Containing Chloro- 
form. 
(2) Proteolytic end-products (2) Proteolytic end-products 
formed. formed. 
(a) Tyrosine in small (a) Tyrosine. 
amounts 
(b) Oxyphenylethylamine. (b) No oxyphenylethyla- 
mine. 
(c) Arginine in traces. (c) Arginine in marked 
quantity. 
(d) Histidine. (d) Histidine. 
(e) Lysine. (e) Lysine. 
(f) Guanidine. (f) No guanidine. 
(g) Traces of putrescine. (g) No putrescine. 
(3) Analysis of cheese. (3) Analysis of cheese. 
(a) Ammonia formed. (a) No ammonia formed. 
(b) Amido compounds (b) Amido compounds less 
more abundant. abundant. 
A consideration of the possible sources of carbon dioxide in 
the two cheeses indicates that, in the case of the chloroformed 
cheese, the carbon dioxide came from that present originally in the 
milk and that formed in the milk from the decomposition of milk- 
sugar before treatment with chloroform. In the case of the normal 
cheese, the carbon dioxide given off in its early age came largely 
from the decomposition of milk-sugar by lactic acid organisms, 
while a small amount was probably due to the carbon dioxide pres- 
ent in the milk and, perhaps, to the respiration of living organisms 
present in the cheese. The carbon dioxide produced after the first 
few weeks came apparently from reactions taking place in some 
of the amido compounds, among which we were able to identify 
the change of tyrosine and arginine into derived products with 
simultaneous formation of carbon dioxide. 
In the chloroformed cheese, the only active proteolytic agents 
were lactic acid, galactase and rennet-pepsin. Under the conditions 
of our experiment, these agents were able to form neither ammonia 
nor secondary amido compounds with production of carbon dioxide. 
The presence of chloroform could not account for this lack of 
action. These results suggest that, in the normal cheese, there must 
have been some agent at work not present in the chloroformed 
cheese and that this extra factor was of a biological character. 
