Identification of saffron aroma compound β-isophorone (3,5,5-trimethyl-3-cyclohexen-1-one) in some V. vinifera grape varieties

Carotenoid-derived aroma compounds play an important role in the composition of aroma and grapes, and consequently of wine. The volatile composition of forty-five grape varieties harvested in 2011 and 2012 was investigated by solid phase extraction of samples and gas chromatography–mass spectrometry (GC–MS) analysis. In grape extracts of cultivars Barbera, Refosco dal Peducolo Rosso, Ribolla gialla and Rossese, the C9-norisoprenoid compound β-isophorone (3,5,5-trimethyl-3-cyclohexen-1-one) was found and quantified. This carotenoid-derived compound is characterised by a saffron aroma and is here reported in grape for the first time.