Analysis of enantiomeric linalool ratio in green and roasted coffee

The enantiomeric distribution of the monoterpene alcohol linalool 3,7‐dimethylocta‐1,6‐dien‐3‐ol was determined by multi‐dimensional gas chromatography (MDGC) and dual‐column switching (DCS) GC–MS for the first time in green and roasted coffee, after extraction by simultaneous distillation–extraction (SDE) and stir‐bar sorptive extraction (SBSE). The sensory impact of the two enantiomers was evaluated in water and by addition experiments to espresso beverage. Post‐harvest treatment of coffee seems to shift the enantiomeric ratio from racemic in washed coffee to an excess of S‐(+)‐linalool in dry processed coffee. Copyright © 2006 John Wiley & Sons, Ltd.