Sunlight-cured tobacco, Bastam, Iran Curing and subsequent growing old let for the sluggish oxidation and degradation of carotenoids in tobacco leaf. This provides particular compounds within the tobacco leaves and provides a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes on the "smoothness" in the smoke. https://broadfar.com/oraco-global-trends-in-heat-not-burn-products/