Headspace solid-phase micro extraction coupled to comprehensive two-dimensional with time-of-flight mass spectrometry applied to the evaluation of Nebbiolo-based wine volatile aroma during ageing

Summary: This study presents the application of a headspace solid-phase microextraction (HS-SPME) method on the analysis of Nebbiolo-based wine volatiles by comprehensive two-dimensional gas chromatography (GC×GC) and time-of-flight mass spectrometry (TOF-MS). The aroma patterns were established for different samples of Nebbiolo-based wines, aged in oak wood barrels for 18 months at constant temperature. The methodology allowed for the simultaneous analysis of over 130 different volatile compounds detected in the headspace. The odour activity values (OAVs) were assessed to identify potentially important odorants of Nebbiolo-based wine during ageing. The highest OAVs were obtained for several compounds such as ethyl octanoate, ethyl hexanoate, isoamyl acetate, β-damascenone, ethyl cinnamate, ethyl 3-methylbutanate and acetaldehyde. Ethyl butanoate, octanoic acid, ethyl dihydrocinnamate and γ-nonalactone were also at concentrations higher than their corresponding threshold. Also vanillin, (E)-whisky lactone, (Z)-whisky lactone, guaiacol and 4-ethyl guaiacol seem to be important odorants after oak wood ageing period.