Thin-layer chromatographic method for the determination of the principal polar aromatic flavour compounds of the cinnamons of commerce
A thin-layer chromatographic method was optimized for the separation of the polar aromatic flavour compounds pertinent to the determination of the botanical source and quality of the cinnamons of commerce. Cinnamaldehyde, eugenol, coumarin, 2-methoxycinnamaldehyde, cinnamyl alcohol and cinnamyl acetate were determined in an acetonitrile extract of powered cinnamon after separation on silica gel layers. Cinnamic acid was determined in a second chromatographic system after separation on DIOL (spacer bonded propanediol) layers. The presence of coumarin or eugenol in proportion to the amount of cinnamaldehyde in the extracts was used to distinguish between the common botanical sources of cinnamon in retail samples of cinnamon oil, stick or powder from four countries.