28 



FERMENTATION OF TOBACCO. 



The changes going on in the fermentation of tobacco and their causes 

 have not been studied very extensively by the experiment stations up 

 to the present. The most attention in connection with this subject 

 has been given to the loss or shrinkage in the weight of the leaves, and 

 in several instances the chemical changes which take place during fer- 

 mentation have been determined. In 1891 and 1892 the Connecticut 

 State Station x compared the weight and chemical composition of cured 

 and fermented leaves. The loss in the fermentation of upper leaves, 

 short seconds, and first wrappers was 9.7, 12.3, and 9.1 per cent of 

 their total weight, respectively. About three-fourths of the loss in 

 the short seconds consisted of water; the upper leaves lost almost the 

 same proportion in dry matter, and in the first wrappers the loss of 

 dry matter was a little less than that of water. The nitric acid, 

 ammonia, fiber, and starch content of the leaves was affected very little 

 by the process of fermentation, and the chief loss of dry matter was 

 found to have occurred in the nicotine, albuminoids and amid bodies, 

 nitrogen-free extract, and ether extract. The upper leaves lost over 

 one-third of their nicotine, the short seconds a little less than half, 

 and the first wrappers less than one-sixth. Fermentation seemed to 

 have been most active in the upper leaves, which lost over one-seventh 

 of their nitrogen-free extract and one-fifth of their ether extract. 

 The first wrappers, which constitute a large and the most valuable 

 part of a good crop, lost only 5.8 per cent of their dry matter, this 

 loss being mainly in the ash, nitrogenous matters other than nicotine, 

 and nitrogen-free extract, which includes the "gum" of tobacco. 

 The author does not consider the loss of ash as having been caused by 

 the process of fermentation. The average results obtained by the fer- 

 mentation of the various experimental crops of tobacco studied by this 

 station for five successive years are of importance in this connection. 2 

 The average loss of weight due to fermentation in the crops of the 

 different seasons ranged from 8. 1 to 11 per cent, but the crop which 

 lost most was not fermented satisfactorily. The average number of 

 leaves per pound of short wrappers was 87 before fermentation and 92 

 after fermentation, and of long wrappers 64 when cured and 68 when 

 the process of fermentation was completed. The largest number of 

 fermented short wrappers and long wrappers per pound from any one 

 plat was 113 and 98, respectively. It was found that the short wrap- 

 pers had an average fire-holding capacity of 12 seconds before and 

 28.5 seconds after fermentation, and the long-wrapper leaves afire- 

 holding capacity of 9.2 seconds before and 23.9 seconds after they had 

 been fermented. 



1 Connecticut State Station Ept., 1892. 2 Ibid., 1897. 



