Characterization of cigar tobaccos by gas chromatographic/mass spectrometric analysis of nonvolatile organic acids: Application to the authenticationof Cuban cigars

reliable method based on gas chromatographic/mass spectrometric (GC/MS) pro filing of nonvolatile organic acids is described for the characterization o f cigars. The method involves an aqueous extraction of ground tobacco and s elective isolation of the acids by simply stirring strong anion exchange (S AX) disks in the aqueous tobacco extract. The acids are then directly silyl ated on the disk with N-methyl-N-trimethylsilyl-trifluroacetamide (MSTFA) i n acetonitrile in an autosampler vial. Elution of the derivatized acids in situ allows the sample to be directly analyzed by GC/MS without further sam ple handling. Compared to the conventional disk-extraction technique using a vacuum manifold, this method is much less labor intensive, and is desirab le for multiple sample analysis. Nicotinic acid, succinic acid, glyceric ac id, malic acid, pyroglutamic acid, threonic acid, citric acid, uracil, and an unidentified acid were reproducibly quantified in tobacco samples. Princ ipal component analysis (PCA) of the acid profiles of the filler tobaccos o f 18 Cuban cigars and 31 non-Cuban cigars shows separation of the two group s, indicating that the acid profiles are potentially useful in the authenti cation of Cuban cigars.