Macrowine 2021
IVES 9 IVES Conference Series 9 Aroma composition of mono-varietal white wines for the production of Custoza

Aroma composition of mono-varietal white wines for the production of Custoza

Abstract

AIM: The appellation “Bianco di Custoza” or “Custoza”, born in 1971, is one of the oldest white wines Protected Designation of Origin in Italy. The production area lies on the morainic hills located south-east of Lake Garda, in the province of Verona. The wines belonging to this appellation are obtained from grapes of main varieties, namely Cortese B., Garganega, Trebbiano Toscano and Tocai Friulano alone or jointly for a minimum of 70% (each one not exceeding a maximum of 45%). In addition, Malvasia, Riesling Italico and Renano, Pinot Bianco, Chardonnay and Incrocio Manzoni (cross between Riesling Renano and Pinot Bianco) varieties, alone or jointly, can contribute to the production for a maximum of 30%. According to the appellation regulation, the sensory profile of these wines should be characterized by fruity and floral notes, sometimes with hints of aromatic herbs and spices.

The purpose of this study was to evaluate the volatile profile of monovarietal wines used in the production of Custoza.

METHODS: Cortese B., Incrocio Manzoni, Trebbiano Toscano, Garganega and Tocai Friulano mono-varietal wines were produced by a local winery during the 2020 vintage. Wines were samples at the end of alcoholic fermentation. Free volatile compounds were analyzed using SPME-GC-MS techniques. All data were treated by analysis of variance (ANOVA) for statistical purposes.

RESULTS: Greater presence of trans-linalool oxide, alpha-terpineol, TDN, methyl salycilate and dimethyl sulfide (DMS) was observed in wines produced from grapes of the Cortese B. variety, one of the four varieties main. Monovarietal wines produced from Incrocio Manzoni grapes, one of the minor varieties, showed a greater content of cis-linalool oxide. In Trebbiano Toscano, a greater content of linalyl acetate and beta-damascenone was observed, while a greater presence of methanthiol was found in wines produced from the Tocai Friulano variety

CONCLUSIONS

This study provided a first insight in the potential contribution of the different varietal wines belonging to the Custoza appellation to the aroma composition of the final wines. For both main varieties (Tocai Friulano, Trebbiano Toscano and Cortese B.) and secondary varieties such as the Incontro Manzoni, differences in terpene, norisporeninds and sulfur compound content were observed. Further studies should investigate whether these differences should be attributed to specific varietal patterns and/or to viticultural and winemaking variables.

ACKNOWLEDGMENT

he present work was supported by Cantina di Custoza

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Beatrice Perina

University of Verona,Davide, SLAGHENAUFI, University of Verona Giovanni, LUZZINI, University of Verona Maurizio, UGLIANO, University of Verona

Contact the author

Keywords

custoza, custoza varieties, white wine, aroma compounds

Citation

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