Starches are converted to sugars. Some proteins are broken down. Slow drying permits aerobic fermentation to take place in the leaves. Other tobacco, especially Turkish or other Oriental tobaccos, is sun dried. After curing the tobacco is allowed to age for 6 months to two years.
Further changes occur in the leaves.
Many flavorings are added to tobacco products. Among these are honey, sugar, oil of hops, licorice, coumarin, rum, menthol, etc. The English soldiers saw the Turks using them and took them home. Since the 1800's, cigarettes have been the main way that tobacco is used. Production of cigarettes is also linked with flue curing of tobacco.