Aroma chemical markers of Durello wines from different vintages and origins: a case study

Abstract

Wines expressing sensory characters that are representative of their varietal and geographical origins are highly sought after in today’s market. It is therefore of considerable technological interest to investigate the aromatic aspects of specific wines and to identify the odorous substances involved. This study investigated aroma chemical and sensory diversity of Durello DOC white sparkling wines. The production of this white wine, based on the use of Vitis vinifera Durella grapes, is located in the hilly area of the eastern Lessini mountains straddling the border between the provinces of Verona and Vicenza. A peculiarity of this denomination is the subdivision of the production area into a further fifteen sub-regions. The aim of this study was the aromatic characterisation of Durello wines. Particular attention was paid to the impact of ageing/vintage and the sub-region of origin of the grapes.

For this study, a sampling of twenty-one commercial Durello provided by the Durello wine consortium was considered. These wines belonged to four different vintages (2016-2019) and seven sub-zones. Free volatile compounds as well as those obtained from the hydrolysis of  glycosidic precursors were quantified with gas chromatography mass spectrometry (GC-MS) analysis coupled with SPE and SPME extractions. Sensory evaluation of wines was carried out through sorting task performed with semi-trained panel. Wines differed significantly in their aroma chemical composition,  , in particular due to vintage/ageing and sub-zones impact. The effect of ageing was appreciable and involved different biochemical classes of compounds: esters, terpenes, norisoprenoids and methyl salicylate. With ageing, a decrease in acetic esters, some ethyl esters, free and bound terpenes and a simultaneous increase in norisoprenoids, some cyclic terpenes and methyl salicylate were found. Differences attributable to the sub-regions were mainly due to terpenes and norisoprenoids but also benzenoids, fatty acids and some sulphur compounds. The sorting task identified two clusters, the main variable associated to sensory differences was vintage/aging but further elements related to production style were identified. 1,4-Cineole was identified as an aromatic marker of Durello sparkling wine.