17 



the assumption of a perfect combustion of the glucose. There are 

 orga: '■'. acids present in the original tobacco leaf, such as citric, malic, 

 and oxalic acids, in the form of neutral salts. A part of these acids 

 may be changed and destroyed in tlie fermentation i)rocess, while other 

 acids n^ay be formed by the changes the glucose undergoes.' The 

 nicotine is bound to organic acids and is not present in the free state j 

 besides, most of the ammonia formed is in combination with organic 

 acids, but a part of it is easily liberated by boiling the aqueous extract 

 of the fermented tobacco. These vapors have a strong alkaline reac- 

 tion and an ammc >iacal odor, and are due either to the volatilization 

 of some ammonium carbonate or to the dissociation of a neutral ammo- 

 nium salt of a bibasic acid. 



Tannin. — The amount of tannin, like that of nicotine, also decreases 

 in fermentation. It varies from 0.3 to 2.3 per cent in commercial 

 tobaccos. The Florida tobacco of 1898 contained only traces of tannin 

 after the fermentation was over. The amount of fatty matter, or, more 

 (correctly si)eakiiig, of substances soluble in ether, was found by Jen- 

 kins ^ to decrease in fermentation from 3.5 to 2.8 i)er cent of the dry 

 matter. Behrens observed in one case a decrease from 9.14 per cent in 

 the cured to 8.31 per cent in the fermented leaf. The amount of such 

 fatty substances was found to vary in dift'ereiit samples from 1.8 to 10 

 per cent and in some cases even more. The decrease of fatty matter 

 during fermentation is probably due to the volatilization of a volatile 

 ethereal oil. It is certainly very improbable that some true fat was 

 oxidized to carbonic acid and water. Little attention has been given 

 thus far to the small amount of resins in tobacco. 



Fiber. — In regard to the fiber, Jenkins determined its amount in 

 Connecticut tobacco as ranging from 13 to 14 -per cent. Fesca and 

 Jmai found the range in Japanese tobacco to be from 13 to 15 i)er cent. 

 Only the ribs contained more — from 22 to 24 per cent. ^ 



Ashes. — The amount of mineral matter is subject to very great vari- 

 ation, namely, from 10 to 27 per cent. 



titrate. — A question of special interest is the fate of the nitric acid 

 probably present exclusively as i)otassium nitrate in fresh leaves. Some 

 authors believe that nitrification goes on during the fermentation proc- 

 ess, which would lead to an increase of nitrate in the fermented leaf. 

 This, however, has never been proved by chemical analysis and is indeed 



' The precipitate obtained by copper acetate from a hot, aqueous extract of fer- 

 mented tobacco contains, among other thin<^s, some succinic acid. The writer did 

 not recognize butyric acid among the volatile acids in Florida tobacco, but acetic 

 acid was i esent. ,,,- 



2 Conn. Ag'-. Expt. Sta., Ann. Kept. 1890. Correct comparison i*: however, possible 

 only in calculating for a constant, e. g., cellulose. 



"^ There are still certain substances in the fermented tobacco which thus far could 

 not be characterized. Some analyses show from 1.7 to 18.9 per cent of nitrogenous 

 extractive matter and from 8.6 to 16.7 per cent of indefinite insoluble matter. There 

 exists great difficulty in isolating certain compounds from these mixtures. 

 15846 2 



