Simulating climate change impact on viticultural systems in historical and emergent vineyards

The creation of disease-resistant varieties adapted to climate change is a key challenge for the future of the wine industry. At present, the selection of these new varieties is essentially based on screening for genetic markers of resistance and agronomic criteria, due to the small number of vines available per genotype. Integrating screening for oenological criteria into the early stages of selection would speed up this process.

Oleocanthal (OC) and oleacein (OL) are highly bioactive secoiridoids found in olive oil at elevated concentrations, especially when it is produced from unripe olives (Olea europaea L.). Both compounds have been correlated with strong activities against serious diseases through recent clinical trials. The most important clinical trials have been performed in patients against chronic lymphocytic

The well-known antifungal and antibiotic molecule, eugenol, is widely spread in various plants including clove, basil and bay. It is also abundant in the hybrid grapevine cultivar (cv) Baco blanc (Vitis vi-nifera x Vitis riparia x Vitis labrusca), created by François Baco (19th century) in the Armagnac region. This study confirmed this cv as highly resistant to Botrytis cinerea by comparing fruit rot incidence and severity with two Vitis vinifera cultivars: Folle Blanche and Ugni Blanc. We have demonstrated the efficiency of eugenol in vitro, by further investigating the effect of small concentrations of eugenol, 3 to 4 ppm (corresponding to IC10), on B. cinerea. By comparing the two major modes of action (direct or volatile antibiosis), the vapour inhibiting effect of eugenol was more powerful. In the skin of Baco blanc berry, the total eugenol concentration reached a maximum at veraison, i.e. 1118 to 1478 μg/kg.

Mouthfeel is an important quality parameter for Chardonnay wines, particularly those aged in oak. While research on mouthfeel has traditionally focused on the impact of non-aromatic compounds, the role of aroma compounds has largely been over looked. However, in wine as well as other food interactions between retronasal aroma and mouthfeel have been noted. The goal of this research was to investigate the impact of wine aroma on the perception of mouthfeel. Because of the importance of oak aging in the development of Chardonnay mouthfeel, the impact of oak aromas on perceived mouthfeel was explored. Aroma compounds associated with oak (ethyl palmitate, eugenol, furfural, isoeugenol, syringaldehyde, vanillin and whiskey lactone) were added to two different Chardonnay wines; one with no oak influence and one fermented in neutral oak. Low and high concentrations of the compounds were added based on concentrations typically found in barrel aged Chardonnay wine.

Oenological tannins are classified as hydrolysable and condensed tannins. Their use in winemaking is only authorized, to facilitate wine fining. Nevertheless, tannins could also be used to prevent laccase effects.