Metabolomics of Vitis davidii Foëx. grapes from southern China: Flavonoids and volatiles reveal the flavor profiles of five spine grape varieties

Increasing concentrations of greenhouse gases (GHGs) in the atmosphere due to human activities are leading to a rise in the average temperature of the atmosphere. among the scenarios established by the un’s intergovernmental panel on climate change (IPCC), only two enable us to achieve the minimum objective of the paris agreements signed at cop 21 in 2015: staying below +2°c after 2050. both scenarios forecast a rapid reduction in GHG emissions as early as 2025, thanks to strong international cooperation, the priority given to sustainable development and responsible consumer choices.

Protein haze in white wines is a major technological and economic problem of the wine industry. Field tests were carried out in steep slope vineyards planted with Riesling grapes over 3 dry growing seasons to study the effect of drought stress on the concentration of proteins in the resulting wines. Plots suffering from drought stress were compared with surrounding drip irrigated plots. Riesling grapes were processed into wines by conventional procedures. Protein amounts of the isolated wine colloids of the stressed samples were always higher than those of the watered samples(mean watered 13.8 ± 0.44, mean stressed 17.4 ± 0.40 g 100 g-1). As a consequence, higher bentonite doses were needed to achieve protein haze stability of the drought stressed treatments.

Galicia is situated in the NW of the Iberian Peninsula, just north of Portugal and so sharing a mild, maritime climate, certain vine species and a number of long-standing viticultural traditions. In Galicia about 18,000 has are dedicated to wine growing, of which roughly half (46%) correspond to the 6 DOs in the area.

Occurrence of freezing temperatures in early spring when grapevine shoots are developing is termed late frost in viticulture. Young green tissues are very sensible to temperatures below zero and damages often lead to important yield and quality losses such as the case in Europe in 2017. An indirect method to avoid late frost damage in vineyards consist in delaying the budburst. Previous research reported similar effects by applying vegetal oil on dormant buds. Here, we tested the application of rapeseed vegetal oil during late winter to delay the budburst on two V.vinifera cultivars of interest in Austria, Grüner Veltliner (GV) and Zweigelt (ZW).

Les enzymes d’oxydation (polyphénoloxydase, peroxydase) des raisins sont d’origine génétique dépendantes des facteurs climatiques et agrotechniques (Sapis et al, 1983). Dans le processus technologique de l’obtention du moût de raisins, ces enzymes catalysent l’oxydation de certains composés phénoliques naturellement présents dans le raisin, produisant ainsi des modifications indésirables de la couleur et de l’arôme du vin.