Aromatic composition and potent odorants of the "specialty coffee" brew "Bourbon Pointu" correlated to its three trade classifications

Amongst all kinds of coffee brews, "specialty coffee" is conspicuous in particular by a unique flavour. "Bourbon Pointu" coffee, Coffea arabica var. laurina, born from a spontaneous mutation of the Bourbon variety in Reunion Island, is a "specialty coffee". This study aims at identifying potent odorants of "Bourbon Pointu" coffee brew according to its three trade classifications "Grand cru", "Sublime" and "Authentique". Solid phase extraction (SPE) permits to extract the volatiles. After their identification by gas chromatography-mass spectrometry (GC/MS), the potent odorants are determined by their odour activity value (OAV). The determination of their OAV allowed one to differentiate coffee brews from the three trade classifications. Aromatic composition of "Bourbon Pointu" coffee is characterised by a predominance of aldehydes with high OAV (e.g. (E,E)-nona-2,4- dienal: 13,600) for coffee brews belonging to "Grand cru" classification, of 2-phenylacetaldehyde (270) for coffee brews of "Sublime" classification and of a group of pyrazine compounds (e.g. 2-methyl-5-propylpyrazine: 16,750) for coffee brews of "Authentique" classification. (Résumé d'auteur