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