August 1, 1864.] THE TECHNOLOGIST. 



CHEMICAL ANALYSIS OF COFFEE. 



31 



The various components in one pound of coffee will be — 



Oz. Grs. 



Water .... 

 Caffeine, or tlieine 

 Casein, or cheese . 

 Aromatic oil 



Gum .... 

 Sugar .... 

 Fat .... 



Potash 



Woody fibre . 

 Mineral matter 



The part roasted is the albumen, which is of a hard, horny con- 

 sistence ; and Lindley remarks that it is probable that the seeds of other 

 plants of this or the stellate order, whose albumen is of the same 

 texture, would serve as a substitute. This would not be the case with 

 those with fleshy albumen. 



Coffee loses in weight by washing, but gains in bulk in proportion 

 to the heat applied. 



Payen found the following amount of nitrogen in 100 parts : — 



1 



407 





122 



2 



35 





H 



1 



192 



1 



17 



1 



402 





080 



5 



262 



1 



31 



Martinique coffee 



Bourbon 



Mocha 



Nitrogen. Ash. 



. 2.46 5-00 



. 1-54 466 



. 2-49 7-84 



The coffee from Martinique lost 11-58 per cent, of its weight by 

 drying. This description of coffee also afforded the following results : 





Unroasted. 



Slightly 

 Beddened. 



Chestnut- 

 Brown. 



Brown. 



Loss in washing 



Increase in bulk... 



40 per cent. 

 48*5 per ct. 



15 percent. 

 1'3 times 

 37 per cent. 



20 per cent. 

 1-53 times. 

 37-1 per ct. 



25 per cent. 

 39-25 per ct. 



Insoluble residue... 



Coffee, as ordinarily prepared for beverage, contains only two- 

 sevenths of the nitrogenous or nutritive matter of the fresh bean, but 

 two-thirds of the washed, and the mineral ingredients are all present. 



M. Lebreton (" Agriculteur praticien") has estimated the loss of 

 weight of coffee in roasting at 18 to 20 per cent., in Porto Eico, Rio, 

 and Martinique coffee ; and at 16 to 18 per cent., in Malabar, Bourbon, 

 Ceylon, and Guadaloupe coffees ; while in Mocha coffee it amounts to 

 only 14 or 16. The loss of weight depends upon the time of roasting 

 and the degree of heat. Damp or damaged coffee loses more than dry 

 sound coffee. He considers that- these substances have the capability of 



