138 Kansas Academy of Science. 



below 200' C, the startling figures obtained concerning the 

 effects of roasting can be readily believed. It has been found 

 that over nine percent of organic material is lost while de- 

 veloping a light-brown color. The lost caffeine is but a frac- 

 tion of one percent, and as the remaining organic substances 

 can only escape by means of decomposition products, this re- 

 sult shows at least nine percent decomposition. How much 

 takes place without escape of the resulting products cannot be 

 stated. 



The results of this decomposition and destructive distillation 

 of the constituents of green coffee are, perhaps, as follows : 



Carbohydrates yield furfuraldehyde. 



Fats yield acrolein. 



Tannins yield catechol, pyrogallol. 



Caffetannic acid contains catechol. 



Proteins contain ammonia, amines and pyrroles. 

 These products of roasting may also interreact to produce 

 many compounds, such as — 



Acrolein -f ammonia = methyl pyridine. 



Methyl pyridine -f furfuraldehyde = furfural vinyl 

 pyridine. 

 This latter compound will produce, on reduction, the alkaloid 

 coniine, which is highly toxic and may be found in the coffee. 

 As a result of the above facts many investigators have tried 

 to separate these products of roasting, mainly by steam distil- 

 lation, and to give them careful examination as to the toxicity 

 of the compounds found. 



Bernheimer found hydroquinone, methyl amine, pyrrole and 

 acetone. Erdmann has found furfuryl alcohol, mixed phenols, 

 valeric acid and furfuraldehyde. Catechol has since been iden- 

 tified as being present. Hydrocarbons have been found that 

 point to the presence of pyridine. 



Mr. Paul D. Potter, chief chemist for Sprague, Warner & 

 Co., has given us much information upon this subject, .and 

 among other things has given the following authoritative in- 

 formation on the toxicity of the various substances found in 

 the volatile principle : 



"Of the phenols, catechol is more toxic than carbolic acid, and pyro- 

 gallol is more toxic than catechol. The harmful influence of the pyridine 

 bases increases with the molecular weight. According to Kendrick and 

 Dewar, they constitute the toxic part of tobacco siaoke, and Williams and 



