Sun-cured tobacco, Bastam, Iran Curing and subsequent getting older enable to the sluggish oxidation and degradation of carotenoids in tobacco leaf. This makes particular compounds within the tobacco leaves and offers a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes towards the "smoothness" from the smoke. https://broadfar.com/nuso-heated-tobacco-smarter-alternative-to-traditional-smoking/