Screening early markers of mildew upon cigar tobacco leaves by gas chromatography–ion mobility spectrometry (GC–IMS) and partial least squares–discriminant analysis (PLS–DA)

Abstract

This study isolated two dominant molds (Penicillium chrysogenum and Aspergillus sydowii) from cigar tobacco leaves. Gas chromatography–ion mobility spectrometry (GC–IMS) was used for rapid qualitative and semi-quantitative analysis of mold growing from 0 to 7 days on potato dextrose agar (PDA). GC–IMS fingerprint, galleryplot, one-way analysis of variance (ANOVA), and partial least squares – discriminant analysis (PLS-DA) were used to assess different periods of cigar tobacco mildew. ANOVA and PLS-DA were compared to identify possible mildew markers in PDA. The potential mildew markers were verified using 0–7 days of artificial mildew samples. The results showed that 1-octene-3-alcohol, 1-pentanol, and pentanal were characteristic markers of early mildew in cigar tobacco. In conclusion, GC–IMS and chemometrics enables early warning of cigar tobacco mold, which is of great significance for storage and quality control.