Analysis of Characteristic “Glutinous Rice”-like Aroma-active Odorants in Flue-cured Tobacco Leaves Based on HS-GC-IMS Combined with ROAV

In order to accurately identify the potent odorants in flue-cured tobacco(FCT) leaves with "glutinous rice"-like characteristic, different Yunyan 87 tobacco leaves with or without typical "glutinous rice"-like characteristic from Yunnan province were used as materials in this study.Firstly, volatile compositions and their relative content was analyzed by headspace-gas chromatography-ion migration spectroscopy(HS-GC-IMS).Then, the differential volatile markers between typical "glutinous rice"-like and non-"glutinous rice"-like tobacco leaves samples and the key chemical contributors to the "glutinous rice"-like characteristic were identified based on the relative odor activity value(ROAV) combined with orthogonal partial least squares discriminant analysis(OPLS-DA).A total of 57 common odorants(including monomers and dimers) were identified.2-Acetyl-1-pyrroline("glutinous rice"-like), benzene acetaldehyde(fruity), nonanal(citrus-like), and 2, 3-butanedione(sweet, buttery)are characterized as differential flavor compounds between typical "glutinous rice"-like and non-"glutinous rice"-like tobacco leaves samples, among which 2-acetyl-1-pyrroline is a key contributor to "glutinous rice"-like aroma, the other three compounds play an important role in modifying "glutinous rice"-like characteristic flavor of FCT.The results herein would provide chemical basis for the accurate regulation and the evaluation method development for "glutinous rice"-like characteristic odorants in FCT.