Tobacconist University
Fermentation
Also known as "Sweating" or "Trabajando", it is the natural, vigorous, highly controlled process that accounts for the majority of flavor + aroma development and distinction in cigar tobaccos. Fermentation occurs when moisture, heat, oxygen, and pressure levels reach a critical synergy: the result is an expulsion of ammonia and other unpalatable organic components of the leaf. The temperatures in Fermentation piles are closely monitored: the piles are deconstructed and re-configured before they get too hot. Tobacco can easily be depleted of flavor + aroma characteristics if over Fermented. Under Fermented tobacco will be noxious, unrefined, and "green" (an industry term with no relation to the leaf color).

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