Insights into the stable isotope ratio variability of hybrid grape varieties

La mise en valeur d’un terroir au travers du vin signifie dans un premier temps le respect du cahier des charges de l’A.O.C correspondante. Dans un second temps, elle sous-entend d’être à l’écoute des évolutions scientifiques, techniques et sociétales afin de satisfaire une production plus respectueuse de l’environnement et de la santé des hommes. Les recherches effectuées par l’Unité Vigne et Vin du centre INRA d’Angers ont débouché sur le concept d’UTB, Unité Terroir de Base (R.Morlat). UTB définit une aire de terrain ou le fonctionnement de la vigne est homogène en tous points.

Aims: Soils are an intrinsic feature of the landscape and have influenced culturally and economically important terroir delineation in many wine-producing regions of the world. Soil physiochemical properties govern a wide array of ecosystem services, and can therefore affect grapevine health and fruit development. These physiochemical properties can reflect a combination of factors,

Given that climate change is a continuous process, it is necessary to constantly search for new strategies that help the viticulturist sector to mitigate its consequences. All adaptation strategies will have a greater or lesser effect that in turn will be marked by the times of action. As a long-term action, a genetic breeding program to obtain new varieties descendant from Monastrell has been developed in the Region of Murcia (more specifically, in the IMIDA Research Center) since 1997. In this program, new red varieties have been developed through directed crosses of the Monastrell variety with other varieties such as Cabernet Sauvignon, Tempranillo and Syrah.

Initiatives have been ongoing in recent years to safeguard biodiversity in the oenological sector via a process of enhancement of ancient varieties, under a pressure of a market strongly oriented towards production deriving from native vines of specific geographical zones. In that sense, Aosta Valley
(Italy) has raised the need to preserve and characterize its minority vine varieties which have the potentiality to give varietal wines. Fumin represents the 7% of the production of the region with 16 hectares of vineyards and 753 hectolitres of derived wine. Due to its large phenolic potential, strong astringency and deep colour, it has long been, and is still today, assembled or blended with other varieties as occurs, for example, for the Torrette.

Astringency sensation decreases slowly during the aging of red wine. Complex reactions of condensation and precipitation of wine polyphenols are involved in this phenomenon. Wine composition and conditions of aging, such as temperature and oxygen availability, strongly influence evolution of the phenol matrix. Recently, a Post-Fermentative cold Maceration (PFM) technique was tested with the aim of accelerating reactions leading to the reduction of astringency and exploiting chemical compounds not extracted from the solid parts of grapes during the previous traditional maceration phase. To this purpose, an innovative maceration system was engineered and used to perform PFM trials on marc derived from vinification of different varieties of red grapes.