Isolation of Toxic Principles of Coffee. 139 



Walters have found that B lutidine affects the heart profoundly. Fur- 

 furaldehyde is considered to be the deleterious agent in raw spirits, and 

 produces a persistent headache in doses of 0.096 grams. Furfuryl 

 alcohol in doses of 0.5 to 0.(5 grams per kilo of body weight will kill a 

 rabbit. The symptoms are lowering of the body temperature, diarrhea 

 and respiratory paralysis. If the nitrites are present, we have in them 

 compounds which, according to Reid Hunt, approach the cyanides in 

 toxicity. The reaction products which may be formed from substituted 

 pyridines (or pyrroles) and furfuraldehyde ai'e of exceeding interest in 

 this connection, for their structural formulae show them to be closely 

 allied to the highly poisonous alkaloids such as nicotine and coniine. 



"In considering the toxic influence of these compounds the possible 

 presence of bodies built up by union of the primary decomposition prod- 

 ucts should not be regarded as far fetched. It is indeed difficult to ac- 

 count for the presence of pyridine in any other way. Further, although 

 furfuraldehyde is the natural decomposition product of carbohydrates, 

 furfuryl alcohol is the principal furane body in coffee oil. Active re- 

 ducing conditions therefore exist within the coffee bean during roasting. 



"It would also be erroneous to conclude that, since the flavor of coffee 

 is due to roasting, all of the decomposition products are necessary to a 

 good product. The flavor is, of course, due to one or more of them, but 

 since it can be developed by longer roasting at a considerably lower tem- 

 perature than is customary in commercial work, it does not follow that 

 all of the decomposition products are desirable. In fact, Erdmann 

 claims to have produced the aroma of coffee by heating caffeine, caffe- 

 tannic acid and sugar.* It would therefore appear that the decomposi- 

 tion products of the proteins and fats are unnecessary and undesirable." 



The toxic effect of all these bodies taken together gives coffee 

 its toxicity. Burmann distilled coffee with steam and obtained 

 these volatile constituents, which he examined for the physio- 

 logical effect. He supposed he had a pure chemical compound, 

 and called it "caffeotoxine." This, however, was proven later 

 by Erdmann to be a mixture of compounds, as before stated. 



Burmann's work, which was on treated coffee or that from 

 which the volatile principle had been removed, shows un- 

 doubtedly that the injurious effects of coffee are from these 

 compounds by his tests, which he sums up as follows: 



(1) From a chemical point of view, treated coffee differs 

 from untreated only in that it contains less of a volatile prin- 

 ciple (caffeotoxine). 



(2) From a physiological point of view, this constituent 

 alone gives coffee its harmful effects. 



(3) The volatile principle has a reducing action on the 

 haemoglobin ; a depressing effect on the blood pressure ; a de- 



* niis we have been unable to do. 



