Sunlight-cured tobacco, Bastam, Iran Curing and subsequent aging allow for for the slow oxidation and degradation of carotenoids in tobacco leaf. This generates specific compounds within the tobacco leaves and provides a sweet hay, tea, rose oil, or fruity aromatic taste that contributes to your "smoothness" of the smoke. https://nmate44062.wikiexpression.com/4208986/an_unbiased_view_of_smoke