Mathematical modeling of fermentation kinetics: a tool to better understand interactions between Torulaspora delbrueckii and Saccharomyces cerevisiae in mixed cultures

l lavoro presenta l’evoluzione dei contenuti di arsenico nelle uve durante lo sviluppo e la maturazione, e la sua distribuzione nell’acino; verifica inoltre la relazione tra i contenuti di As nelle uve

Dehydrodicatechins have recently received attention as oxidation markers especially in grapes and wine. Their analysis mainly uses LC-MS/MS which is able to differentiate them from their natural isomers (dimeric procyanidins), based on specific fragments

The vocabulary used to describe wine aroma is commonly organized according to color, raising the question of whether they reflect the reality of olfactory perception. Previous studies have assumed this convention of color-aroma matching, and have investigated color’s influence on the perception of aroma only in dyed white wine or in red wine from particular places of origin. Here 48 white and red varietal wines from around the world were evaluated in black glasses then in clear glasses by a panel of wine experts, who gave intensity ratings for aroma attributes commonly used by wine professionals. In black glasses, aromas conventionally associated with white wine were perceived in the red wines, and vice versa.

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.

Une étude a été menée pendant neuf ans sur deux vignes non-irriguées de Sauvignon blanc commercialisés, plantées à différentes localités (A et B) dans le district de Stellenbosch. Deux parcelles expérimentales, situées sur deux formations géologiques différentes, ont été identifiées au sein de chaque vignoble. A chaque localité une des