Impact of winemaking processes on wine polysaccharides, improving by qNMR

Mediterranean viticulture is increasingly exposed to more frequent extreme conditions such as heat waves. These extreme events co-occur with low soil water content, high air vapor pressure deficit and high solar radiant energy fluxes and result in leaf and berry sunburn, lower yield, and berry quality, which is a major constraint for the sustainability of the sector. Grape growers must find ways to proper and effectively manage heat waves and extreme canopy and berry temperatures. Irrigation to keep soil moisture levels and enable adequate plant turgor, and convective and evaporative cooling emerged as a key tool to overcome this major challenge. The effects of irrigation on soil and plant water status are easily quantifiable but the impact of irrigation on soil and canopy temperature and on heat convection from soil to cluster zone remain less characterized. Therefore, a more detailed quantification of vineyard heat fluxes is highly relevant to better understand and implement strategies to limit the effects of extreme weather events on grapevine leaf and berry physiology and vineyards performance. Low-cost sensor technologies emerge as an opportunity to improve monitoring and support decision making in viticulture. However, validation of low-cost sensors is mandatory for practical applicability. A two-year study was carried in a vineyard in Alentejo, south of Portugal, using low-cost thermal cameras (FLIR One, 80×60 pixels and FLIR C5, 160×120 pixels, 8-14 µm, FLIR systems, USA) and pocket thermohygrometers (Extech RHT30, EXTECH instruments, USA) to monitor grapevine and soil temperatures. Preliminary results show that low-cost cameras can detect severe water stress and support the evaluation of vertical canopy temperature variability, providing information on soil surface temperature. All these thermal parameters can be relevant for soil and crop management and be used in decision support systems.

Aim: The notion of “terroir” enables the attribution of distinctive characteristics to wines from the same region. Climate change raises issues about viticulture, especially the growth of the vines and even more importantly the economic situation of actual wine-growing regions (Schultz and Jones 2010; Quénol 2014). Several studies have addressed the impacts of climate change on viticulture in

Disease-resistant hybrid grape cultivars (DRHGCs) are hybrids of Vitis vinifera varieties with other Vitis species, and they are endowed with greater resistance to specific fungal diseases, enabling a potential reduction in the application of pesticides in the vineyard.

La caractérisation des sols en vue d’une étude de terroirs viticoles peut être réalisée à différents niveaux de complexité, suivant le nombre de variables pris en compte et suivant le fait que celles-ci sont spatialisées ou non

The browning index (BI), based on the absorbance at 420 nm, is a common oxidation marker in white wines, typically measured after thermal stress (50–60 °C for 5 up to 12 days) in air-saturated wines.