Phenolics, aroma profile, and in vitro antioxidant activity of Italian dessert passito wine from Saracena (Italy)

Abstract

A traditional sweet dessert wine from Saracena (Italy), made with nonmacerated local white grapes (Guarnaccia, Malvasia and Moscato), was analyzed for phenolics and aroma profile and antioxidant activities. The most abundant classes of phenols identified by high-performance liquid chromatography were hydroxybenzoic acids and flavan-3-ols, where gallic acid showed the highest content (376.5 mg/L). The analysis by solid phase microextraction-gas chromatography-mass spectrometry revealed the presence of superior alcohols (from iso-butanol and iso-amyl alcohol up to 2-phenylethanol) and their ethyl esters, terpenes (such as linalool), furfuryl compounds, and free fatty acids (up to palmitic acid) as the key odorants of this wine. The antioxidant activity, evaluated by different in vitro assays 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and β-carotene bleaching test), showed that passito wine had a radical scavenging activity (IC50 value of 0.03 v/v against DPPH·) and inhibited linoleic acid oxidation with an IC50 value of 0.4 v/v after 30 min of incubation.