Terroir effects from the reflectance spectra of the canopy of vineyards in four viticultural regions

Le terroir viticole, qui est la base de la délimitation des aires d’Appellation d’Origine Contrôlée, est une notion complexe dans laquelle sont en interaction la vigne, les facteurs naturels tels que le sol, le climat, ainsi que le facteur humain à travers les pratiques des viticulteurs. Le terroir conditionne la composition des raisins et ainsi la qualité et la typicité des vins qui en sont issus.

Climate change is leading to a rise in average temperature and in the frequency and severity of heatwaves, and is already significantly disturbing grapevine phenology and berry composition. With the evolution of the weather of Australian grape growing regions that are already warm and hot, flavonoids, for which biosynthesis depends on bunch microclimate, are expected to be impacted. These compounds include anthocyanins and tannins which contribute substantially to grape and wine quality. The goals of this project were to determine if berry tannin accumulation is sensitive to high temperature and to enhance knowledge on upper temperature limits for viable wine production, in turn informing critical timing for mitigation strategies.

The mapping of spatial variability in vineyards offers the potential to implement zonal management strategies with the aim to optimize economic benefits and increase sustainability by managing natural resources, such as water used for irrigation, more optimally. This study characterized the (natural) variability in plant water status in a commercial Cabernet Sauvignon block, using remote sensing techniques, and identified the impact of this variability on the yield, and juice and wine composition. From the field data collected over two growing seasons, we demonstrated that remote sensing techniques are a practical and powerful tool for mapping spatial variability within vineyard blocks.

Originally, the role of the malolactic fermentation (MLF) was simply to improve the microbial stability of wine via biological deacidification. However, there is an accumulation of evidence to support the fact that lactic acid bacteria (LAB) also contribute positively to the taste and aroma of wine. Many different LAB enter into grape juice and wine from the surface of grape berries, cluster stems, vine leaves, soil and winery equipment. Due to the highly selective environment of juices and wine, only a few types of LAB are able to grow.

Les aires d’appellations de la Côte d’Or résultent d’une sélection humaine empirique, historique et évolutive en adéquation avec les facteurs naturels. Afin de comprendre quels facteurs naturels et humains agissent sur le caractère et l’évolution des terroirs des Côtes de Nuits et de Beaune, une méthodologie de recherche a été développée. Elle s’articule autour de deux axes, la caractérisation physique des lieux-dits viticoles et l’historicité de la qualité de ces lieux-dits. Le travail avec un S.I.G permet d’étudier l’évolution spatiale et temporelle de la qualité.