Jan. 1, 1865.] 



THE TECHNOLOGIST. 



ON CHEMISTRY APPLIED TO THE ARTS. 



279 



this point, as well as the modifications which cryptogamic life under 

 peculiar circumstances may effect in the composition of organic sub- 

 stances, and his interesting results were obtained in studying the con- 

 version of curd into the well-known cheese of Roquefort. He placed in 

 a cellar some curd of the following composition : — 



Caseine 

 Fatty matters 

 Lactic acid . 

 Water 



85-43 

 1-85 

 0-88 



11-84 



100-00 



To which he added a small quantity of salt. After a month, and again 

 after two months, he analysed portions of the same, with the following 

 results : — 





After one month. 



After two months 



Caseine 



61-33 



43-28 



Fatty matters 



16-12 



32-31 



Chloride of sodium . 



4-40 



4-45 



Water 



18-15 



19-16 



Butyric aeid 



— 



0-67 



100-00 



99-87 



The above figures show a most extraordinary change in the caseine or 

 curd, for we observe that the proportion of caseine gradually decreases, 

 and is replaced by fatty matters. Considering the circumstances under 

 which this phenomenon has occurred, there can be no doubt that this 

 curious conversion of an animal matter into a fatty one is due to a 

 cryptogamic vegetation or ferment ; and if the Roquefort cheese be ex- 

 posed to the air under a bell jar for twelve months, the decomposition 

 becomes still more complete ; for it is no longer the caseine which 

 undergoes a transformation, but the oleine of the fatty matters. The 

 following analyses clearly illustrate this curious action. Composition of 

 the cheese after two and twelve months : — 





After two months. 



After twelve months 



Caseine . 



43-28 



40-23 



Margarine 



18-30 



16-85 



Oleine 



1400 



1-48 



Butyric acid 



0-67 



— 



Common salt 



4-45 



4-45 



Water . 



19-30 



15-16 



Butyrate of ammonia 



— 



5-62 



Caproate of ammonia 



— 



7-31 



Carprylate of ammonia 



— 



4-18 



Caprate of ammonia 



— 



4-21 



100-00 



99-49 



The substances to which cheeses owe their peculiar flavour are 

 ammoniacal salts, chiefly composed of various organic acids, such as 



VOL. V. K K 



