Effects of thermal drying methods on characteristic volatile organic compounds of passion fruit (Passiflora edulis Sims) peel: A multi-analytical approach combining GC–MS, GC-IMS, E-nose, and multivariate statistical analysis

This study systematically evaluated thermal drying methods effects on characteristic volatile organic compounds of passion fruit peel using E -nose, GC–MS, GC-IMS combined with multivariate statistical analysis. Specifically, GC–MS exhibited higher sensitivity for hydrocarbons and other compounds, whereas GC-IMS was esters, aldehydes, and alcohols. Multiple Factor Analysis confirmed that the combination of these two methods was shown to more comprehensively evaluate the volatile flavor compounds and aroma characteristics of passion fruit peel. Overall, HPD exhibited the best retention of characteristic volatile organic compounds (e.g., Methyl benzoate-M, Nonanal, Decanal), generated new compounds (e.g., (E)-2-octenal, Benzaldehyde, 2-methylbutanal) and enriched the aroma characteristics (e.g., apple, chocolate, fruity). Therefore, HPD was recommended as the optimal pretreatment method for obtaining the best aroma quality of passion fruit peel. Besides, methyl benzoate could serve as a key marker for evaluating the aroma quality of passion fruit peel dried by VMD.