terclim by ICS banner
IVES 9 IVES Conference Series 9 Investigating the impact of grape exposure and UV radiations on rotundone in Vitis vinifera L. Tardif grapes under field trial conditions

Investigating the impact of grape exposure and UV radiations on rotundone in Vitis vinifera L. Tardif grapes under field trial conditions

Abstract

Rotundone is the main aroma compound responsible for peppery notes in wines whose biosynthesis is negatively affected by heat and drought. Through the alteration of the precipitation regime and the increase in temperature during maturation, climate change is expected to affect wine peppery typicality. In this context there is a demand for developing sustainable viticultural strategies to enhance rotundone accumulation or limit its degradation. It was recently proposed that ultraviolet (UV) radiations could stimulate rotundone production. The aim of this study was to investigate under field trial conditions the impact of grape exposure and UV treatments on rotundone in Vitis vinifera L. Tardif, an almost extinct grape variety from south-west France that can express particularly high rotundone levels. Four different treatments were compared in 2021 to a control treatment using a randomised complete block design with three replications per treatment. Grape exposure was manipulated through early or late defoliation. Leaf and laterals shoots were removed at Eichorn Lorenz growth stages 32 or 34 on the morning-sun side of the canopy. During grape maturation, UV radiations were either reduced by 99% by installing UV radiation-shielding sheets, or applied four times using the Boxilumix™ non thermal device (Asclepios Tech, Tournefeuille) with the aim of activating plant signalling pathway. Loggers displayed in solar radiation shields were used to assess the effect of such shielding sheets on air temperature within the bunch zone. The composition of grapes subjected to these treatments will be soon analysed for their rotundone content and basic classical laboratory analyses. Grapes will be harvested to elaborate wines under standardized small-scale vinification conditions (60kg) that will be assessed by a trained sensory panel. 

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Olivier Geffroy1, Thomas Baerenzung dit Baron1,2, Christian Chervin3, Chloé Cuif1, Carole Feilhès4, Elodie Gassiolle5, Christine Roynette6, Valérie Simon2 and Alban Jacques1

1Physiologie, Pathologie et Génétiques Végétales (PPGV), INP-PURPAN, Toulouse, France
2Laboratoire de Chimie Agro-Industriel (LCA), INP-ENSIACET, Toulouse, France
3Génomique et Biotechnologie des Fruits (GBF), INP-ENSAT, Toulouse, France
4Institut Français de la Vigne et du Vin pôle Sud-Ouest, Lisle-sur-Tarn, France
5Plaimont Producteurs, Saint-Mont, France
6AsclepiosTech, Tournefeuille, France

Contact the author

Keywords

rotundone, defoliation, UV radiations, shielding sheets, signalling pathway

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Tuning the pH during the fermentation has a strong effect on the wine protein composition and the stability of the resulting white wines

Previous results have shown the impact of the pH on the stability of white wine proteins. In a context of global warming that implies increases in ethanol content and pH

Read More

El medio natural de Chile como factor de adaptación de la vid

Chile, junto con Australia, EE.UU., Sudáfrica, Argentina y Nueva Zelanda constituye el grupo de países del nuevo mundo vitivinícola. Todos ellos en conjunto han experimentado en la última década

Read More

Bio-modulating wine acidity: The role of non-Saccharomyces yeasts

In this video recording of the IVES science meeting 2021, Alice Maria Correia Vilela (University of Trás-os-Montes and Alto Douro, Vila Real, Portugal) speaks about bio-modulating wine acidity: the role of non-Saccharomyces yeasts. This presentation is based on an original article accessible for free on IVES Technical Reviews.

Read More

Analysis of voltammetric fingerprints of different white grape musts reveals genotype-related oxidation patterns

Must oxidation is a complex process involving multiple enzymatic transformations, including the oxidation of phenolics containing an ortho-diphenol function. The latter process has a primary influence on wine aroma characteristics and stability, due to the central role of ortho-diphenols in the non-enzymatic oxidative reactions taking place during winemaking and in finished wine. Although oxidation of must is traditionally avoided, in recent years its contribution to wine quality has been revisited, and in some cases improvements to wine aroma have been observed with the application of controlled must oxidation. Nowadays there is a great interest in the wine industry towards the identification of specific markers or patterns to characterize and classify the response of grape must to oxidation.

Read More

Screening sensory-directed methodology for the selection of non-saccharomyces wine yeasts based on perceived aroma quality

The present work contributes by developing a rapid sensory-directed methodology for the screening and selection of high quality wines with different sensory profiles Therefore, Verdejo and Tempranillo musts were fermented with 50 different yeasts each under controlled laboratory conditions. Resulting samples were firstly categorized according to five levels of quality by a panel of wine professionals (Sáenz-Navajas, Ballester et al. 2013). Higher quality samples were described by flash profiling by a semi-trained panel
(Valentin, Chollet et al. 2012) and most distinctive samples were screened by gas chromatography-olfactometry (GC-O) (López, Aznar et al. 2002).

Read More