Sunshine-cured tobacco, Bastam, Iran Curing and subsequent aging enable for your slow oxidation and degradation of carotenoids in tobacco leaf. This generates selected compounds from the tobacco leaves and offers a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes on the "smoothness" in the smoke. DNA. https://broadfar.com/non-combusted-cigarettes-a-safer-alternative-or-just-a-myth/