Key Aroma Analysis and Investigation of Microscopic Perception Mechanisms of Cigar Tobacco Leaves

ABSTRACT Cigars, as a unique tobacco product, not only possess a rich aroma and a full‐bodied taste but also offer a complex sensory experience. Systematic research on the aroma composition and microscopic perception mechanisms of cigar tobacco leaves (CTLs) was crucial for improving cigar quality. In this work, the aroma characteristics of four CTLs from different origins were systematically investigated by using headspace solid‐phase microextraction‐gas chromatography‐olfactory‐mass spectrometry, resulting in the identification of 94 volatile compounds. Then, combining aroma extract dilution analysis and odour activity value, eight key aromatic compounds (KACs), including β‐ionone, dihydro‐beta‐ionone, and benzaldehyde, were screened. Molecular docking results showed that β‐ionone and dihydro‐beta‐ionone exhibited a wide range of strong binding abilities with olfactory receptors (ORs), with binding energies ranging from −7.6 to −5.12 kcal/mol, significantly stronger than those of other KACs, which was attributed to their unique cyclohexene configurations. Further analysis of the relationship between molecular configurations and binding energies revealed that rigid cyclic molecules typically had lower binding energies, while flexible long‐chain molecules possessed more torsional bonds, resulting in higher torsional free energies during docking with ORs, thus reducing their affinity for ORs. Molecular dynamics simulations of the complexes formed by the eight KACs and ORs indicated that the root mean square deviation and radius of gyration stabilised after 25 ns, with root mean square fluctuation generally below 1 nm, suggesting that the complex systems were dynamically stable. This work provided a theoretical basis and technical support for the development of specialty cigar products and deepened the microscopic understanding of cigar flavour formation.