Sun-cured tobacco, Bastam, Iran Curing and subsequent getting older enable for your gradual oxidation and degradation of carotenoids in tobacco leaf. This makes particular compounds in the tobacco leaves and provides a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes on the "smoothness" in the smoke. https://broadfar.com/oraco-pioneering-a-smokeless-future-with-innovative-nicotine-delivery/