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IVES 9 IVES Conference Series 9 How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

Abstract

One of the major issues for the wine sector is the impact of climate change linked to the increasing temperatures which affects physicochemical parameters of the grape varieties planted in Bordeaux vineyard and consequently, the quality of wine. In some varietals, the attenuation of their fresh fruity character is accompanied by the accentuation of dried-fruit notes [1]. As a new adaptive strategy on climate change, some winegrowers have initiated changes in the Bordeaux blend of vine varieties [2]. This study intends to explore the fruitiness in wines produced from grape varieties adapted to the future climate of Bordeaux. 10 commercial single–varietal wines from 2018 vintage made from the main grape varieties in the Bordeaux region (Cabernet franc, Cabernet-Sauvignon and Merlot) as well as from indigenous grape varieties from the Mediterranean basin, such as Cyprus (Yiannoudin), France (Syrah), Greece (Agiorgitiko and Xinomavro), Portugal (Touriga Nacional) and Spain (Garnacha and Tempranillo), were selected among 19 samples using sensory descriptive analyses. Both sensory and instrumental analyses were coupled, to investigate their fruity aroma expression. For sensory analysis, samples were prepared from wine, using a semi preparative HPLC method which preserves wine aroma and isolates fruity characteristics in 25 specific fractions [3,4]. Fractions of interest with intense fruity aromas were sensorially selected for each wine by a trained panel and mixed with ethanol and microfiltered water to obtain fruity aromatic reconstitutions (FAR) [5]. A free sorting task was applied to categorize FAR according to their similarities or dissimilarities, and different clusters were highlighted. Instrumental analysis of the different FAR and wines demonstrated variations in their molecular composition. Results obtained from sensory and gas chromatography analysis enrich the knowledge of the fruity expression of red wines from “new” grape varieties opening up new perspectives in wine technology, including blending, thus providing new tools for producers.

References

[1] Pons A. et al. 2017, OENO One 51, 141-146
[2] Van Leeuwen C. et al. 2019, Agronomy 9, 514
[3] Ferreira V. et al. 1999, Journal of Chromatography 864, 77-88
[4] Pineau B. 2007, Doctoral dissertation, Bordeaux 2
[5] Lytra G. 2012, Journal of Agricultural and Food Chemistry 60, 12260-12269

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Justine Garbay, Margaux Cameleyre, Nicolas Le Menn, Jean-Christophe Barbe and Georgia Lytra

Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, Univ. Bordeaux, Villenave d’Ornon France

Contact the author

Keywords

aromatic compounds, climate change, fruity notes, late-ripening varieties, red wine

Tags

IVES Conference Series | Terclim 2022

Citation

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