Sunshine-cured tobacco, Bastam, Iran Curing and subsequent ageing allow for to the slow oxidation and degradation of carotenoids in tobacco leaf. This provides sure compounds during the tobacco leaves and offers a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes into the "smoothness" of the smoke. https://broadfar.com/non-combusted-cigarettes-a-safer-alternative-or-just-a-myth/