Identification of the Odorants of Two Passito Wines by Gas Chromatography-Olfactometry and Sensory Analysis

Abstract

Aromatic characterization of two Sicilian passito wines, Malvasia delle Lipari and Moscato di Noto, was carried out by a combination of sensory analysis and gas chromatography-olfactometry (GC-O) techniques (OSME method). The wines were obtained from aromatic grape cultivars submitted to different methods of drying. A triangular test was used to evaluate olfactory differences between the two wines and a descriptive analysis identified characteristic odor descriptors with the highest percentage of citations. Volatile components were extracted, identified by GC-MS, and evaluated by GC-O. Of the volatiles present, 31 odorants in Malvasia delle Lipari and 30 odorants in Moscato di Noto were detected. The odor impact of each odorant was measured by the area under peak curve (AUC) value calculated by persistence and intensity values. Comparison of AUC values of all odorants showed that 3-methylbutanoic acid (pungent spices) and dimethyloctendiol (sweet flowers) characterized for Malvasia delle Lipari, while hexanal (cut grass), linalool (floral), 1-terpinen-4-ol (tropical fruit), 3-mercapto-1-hexanol (grass), 4-ethylguaiacol (phenolic), 2-methoxy-4-vinylphenol (burnt wood), and one unidentified phenolic component characterized for Moscato di Noto.