Red wine oxidation study by accelerating ageing tests and electrochemical method

The postharvest dehydration of grapes is a traditional practice to obtain wines with unique traits (e.g. sweet, dry/reinforced). The modern facilities (dehydrating rooms) used for this purpose are equipped with systems for artificially controlling the inside environment parameters, to obtain the desired dehydration kinetic and preserve the grapes from grey mold (Botrytis cinerea) infection, However, the conditioning systems are extremely energy-demanding and the identification and practical applications of solutions effective in controlling/reducing the postharvest decay would reduce the costs of the operation of the dehydration facilities. To this end, we explored the potential of ozone-based treatments on harvested grapes and preliminarily tested if the treatment could impact the normal behavior and metabolism of grapes during the traditionally slow dehydration practice.

Viti-tunnel®, une innovation imaginée pour répondre à deux des objectifs majeurs des viticulteurs : 1.la sécurisation de la vendange : viti-tunnel® permet de protéger les vignobles des pertes de récolte dues aux maladies, au gel et à la grêle. 2.la réduction des pesticides : viti-tunnel® permet de réduire de plus de 90 %, le recours aux produits phytosanitaires et aux passages de pulvérisateurs, et ce, en toute sécurité pour la vendange. Un dispositif automatisé pour protéger les vignes viti-tunnel® est un dispositif de mise à l’abri automatique des rangs de vigne pendant les pluies et les évènements climatiques extrêmes.

Reduced off-flavour is an organoleptic defect due to an excess of volatile sulfur compounds (VSC) in wine and often happening in Shiraz wines. This off-flavour is a direct consequence of the lack of oxygen flow during winemaking and bottle storage. Therefore, wine closure could have a direct impact on the formation of VSC due to the oxygen transfer rate that can modulate their levels. Even if dimethylsulfide (DMS) contributes to reduced off-flavor, it is also a fruity note enhancer in wine and its evolution during wine ageing is not well understood.

The combination of cover crops with regulated deficit irrigation has been lately shown to be a good method to improve harvest quality in irrigated vineyards of Southern Europe with semiarid climate, as an alternative to the conventional management, that consists on mechanical tillage and irrigation from fruitset to veraison and from then on reduced, or even ended.

The balance between the different flavours of a wine largely determines its perception and appreciation by the consumers. In white wines, sweetness and sourness are usually the two poles balancing the taste properties. The bitter flavour, on the other hand, is frequently associated with a loss of equilibrium and all white wines (dry and sweet, young and aged) are affected.
Several bitter compounds are already well-described in wines.