Evaluation of volatile and chemical profile of sherry-like white wine Vernaccia di Oristano from Sardinia by comprehensive targeted and untargeted approach

Abstract

This study investigated the chemical–physical and volatile profile of sherry-like white wines with different aging time from three different areas of Sardinia. Proximate chemical composition, CIELab color coordinates and absorbances at 280 and 420 nm were determined. Volatile compounds were determined by solid-phase microextraction (SPME) followed by gas chromatography coupled with a mass spectrometer (GC/MS) using a targeted and untargeted approach. Significant correlations among the age of the wine and most of the chemical physical parameters, such as alcohol content, total acidity, volatile acidity, glycerol and polyphenols were observed. A280 and A420 values were highest, as expected, in the oldest wines as well as an increase of a* low values for L* were found during aging. Fifty-nine volatile compounds were identified, among which ethyl acetate, amyl/iso-amyl alcohol, ethyl octanoate, benzaldehyde, ethyl decanoate and phenylethyl alcohol were predominant. The untargeted approach was able to discriminate wines according to their production area, and within each group, according to the year of production.