Sunshine-cured tobacco, Bastam, Iran Curing and subsequent growing older allow for your slow oxidation and degradation of carotenoids in tobacco leaf. This creates specified compounds inside the tobacco leaves and gives a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes towards the "smoothness" with the smoke. https://broadfar.com/nuso-heated-tobacco-smarter-alternative-to-traditional-smoking/