Influence du terroir sur la composition en flavonoïdes de la baie de raisin de Cabernet franc en Moyenne Vallée de la Loire

Sulfur dioxide is the most commonly used additive in oenology to protect wine from oxidation and microorganisms. Once added to wine SO2 is able to react with carbonyl compounds to form carbonyl bisulfites what affects their reactivity.

Commercial oenological tannins (TECs) are widely used in the wine industry. TECs are rich in condensed tannins, hydrolyzable tannins or a mixture of both. Wine grapes are a important source of proanthocyanidins or condensed tannins while oak wood possess a high concentration of hydrolyzable tannins (Obreque-Slier et al., 2009). TECs contribute with the antioxidant capacity of wine, catalyze oxide-reduction reactions and participate in the removal of sulfur compounds and metals.

L’entreprise viticole Concha y Toro S.A. gère environ 600 ha de vignes dans la Vallée du Maipo (A.O. Valle del Maipo). L’objectif est celui de caractériser spatialement ces vignobles et leur occupation du sol environnante. Le choix s’est porté vers la démarche de zonage viticole par l’analyse spatiale, utilisant des traitements d’images satellitaires afin d’avoir une vision synoptique de la zone à moindres coûts et délais. Un système d’informations géographiques (SIG) est construit à partir des données suivantes : cartes topographiques, géologique, fond cadastral numérique, images satellitaires. Un modèle numérique de terrain est par ailleurs construit à une résolution de 25 m à partir des cartes topographiques.

Sessile oak and pedunculate oak have shown several differences of interest for enological purposes. Tannic and aromatic composition among sessile oak or pedonculate oak has been well studied. Sessile oak is generally more aromatic than pedunculated, while the later is more tannic. This scientific point of view is rarely applied to classify oak in cooperages. Most coopers use the type of grain to distinguish wide and thin grain.

The use of pesticides for vine growing is responsible for generating an important volume of wastewater. In 2009, 13 processes were authorized for wastewater treatment but they are expensive and the toxicological impact of the secondary metabolites that are formed is not clearly established. Recently photodecomposition processes have been studied and proved an effectiveness to degrade pesticides and to modify their structures (Maheswari et al., 2010, Lassale et al., 2014). In this field, Pulsed Light (PL) seems to be an interesting and efficient process (Baranda et al., 2017). Therefore, the aim of this work was to investigate the PL technology as a new process for the degradation of pesticides.