Curing largely determines the usability and style of tobacco. Drawing on tea processing, we developed three methods using fresh tobacco leaves: a black tea–like process with wilting, rolling, fermentation, and drying (TR), and two green tea key steps that replace rolling with steaming (TZ) or pan-firing (TC) to shape distinct aroma styles, and these were compared with conventional flue-curing (CK). Sensory quality was evaluated by a trained panel and an electronic nose (E-nose). Enzyme activities, macromolecular constituents, major chemical components, and volatile organic compounds (VOCs) were systematically analyzed. The results showed that TR achieved the highest overall sensory performance, with CK and TC comparable, and TZ the lowest. E-nose patterns clearly discriminated the treatments and covaried with aroma scores, reflecting differences in aroma style. Enzymatic reactions induced by TR processing led to a marked decrease in polyphenols, while facilitating macromolecular degradation and promoting the accumulation of key VOCs, including phenylacetaldehyde, indole, and 4,7,9-megastigmatrien-3-one. In contrast, high-temperature pretreatments in TZ and TC rapidly inactivated enzymes before fermentation, leading to higher polyphenol retention but limited macromolecular degradation and key aroma development. Overall, macromolecules are primary negative drivers of sensory quality, whereas chemical balance and key aroma constituents support higher scores. These results indicate that targeted manipulation of key processing steps can effectively direct the formation of tobacco quality and flavor differentiation, while potentially regulating the formation of certain undesirable components. This study provides valuable support for advancing diversified tobacco-curing methods and generating tobacco leaf materials with distinct flavor profiles.
Liu et al. (Tue,) studied this question.