Importance of Storage, Aging, and Fermentation

Outstanding effects of aging or fermentation are development of the desired aroma, elimination of harshness, improvement of the bitter taste, and disappearance of green shades. The leaf acquires a darkened color, diminished luster and stickiness, improved combustibility, and reductions of irritating qualities in its smoke. 

Modern Methods of Plant Analysis, Volume 15 Alkaloids (ed. by Linskens/Jackson) 

Nornicotine Formylanatabine (FAT) 4-(Methylnitrosamino)- 2,3 -Dipyridyl l-(3-pyridyl-)-l- ( bipyridyl ) butanone (NNK) 

Isopropylnomicotine n-Octanoylnornicotine (ONN) 4-(Methylnitrosamino)-1 -(3-py ridyl)-1 -butanol (NNAL) 

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