Aroma composition of young and aged Lugana and Verdicchio

Abstract

AIM: Verdicchio and Lugana are two Italian white wines produced in the Marche and Garda lake regions respectively. They are however obtained using grape varieties sharing the same genetic background, locally known as Verdicchio in Marche and Trebbiano di Soave in Garda. Anecdotal evidence suggests that these two wine types exhibit distinctive aroma features. The aim of this work was to explore the existence of a recognizable odour profile for Lugana and Verdicchio, and whether specific aroma chemical markers could be identified.

METHODS: 13 commercial wines, 6 Lugana and 7 Verdicchio were used. Sensory analysis was done using sorting task methodology, assessing only odor similarities. A total of 53 volatile compounds were identified and quantified GC-MS analysis. Aging behaviors were also evaluated after an accelerated aging at 40 ° C for 3 months.

RESULTS: HCA analysis of sorting task data identified indeed two groups: one characterized by floral and minty notes and mostly associated with Lugana wines, the other characterized by spicy and toasted aromas and mostly associated with Verdicchio. From a chemical point of view, major differences between the two wines types were observed for cis-3-hexenol, methionol, phenylethyl alcohol, and geraniol. Lugana wines showed generally higher contents of terpenes, esters and methyl salicylate. Methyl salicylate was found in both wine types, in Lugana reaching concentrations greater than 105 µg/L. Methyl salicylate content of these wines was generally much higher than that reported for other wine types, so that this compound could be considered as varietal marker of Lugana and Verdicchio wines. Samples after accelerated aging showed that Lugana formed higher amount of p-cymene, while Verdicchio was characterized by the formation of vitispirane.

CONCLUSIONS:

Significant differences exist between Lugana and Verdicchio wines both at a sensorial and chemical level. These results highlight that environment and viti-enological practices play a fundamental role in the aroma expression of wines in spite of the very similar genetic background of the grape.

DOI:

Publication date: September 16, 2021

Issue: Macrowine 2021

Type: Article

Authors

Davide Slagheanufi

Department of Biotechnology, University of Verona, Italy, Filippo FORTE, Department of Biotechnology, University of Verona Riccardo MANARA, Department of Biotechnology, University of Verona Giovanni LUZZINI, Department of Biotechnology, University of Verona Maurizio UGLIANO, Department of Biotechnology, University of Verona

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Keywords

lugana; verdicchio; wine aroma; chemical signature; sortin task

Citation

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