The influence of culture medium on the dynamics of fermentation of wine yeasts

The wine industry generates each year 20 million tons of by-products. Among them grape pomaces represent a big part that can be considered as a source of potentially bioactive molecules such as polyphenols. Kombucha fermentation is an ancestral process which allow to increase the biological properties of tea by the action of a microbial consortium formed by yeasts and bacteria called scoby.

Vine genetics, fruit maturity, region and vineyard are perceived as factors that strongly influence Pinot noir grape and wine composition. Our study aims to understand the relationship between grape (and ultimately wine) composition and the physical appearance and performance characteristics of a vine (i.e. vine ideotype). Our experimental approach controlled these variables by

Grapevine powdery mildew caused by Erysiphe necator and Botrytis bunch rot caused by Botrytis cinerea are two of the most important fungal diseases in California grape production.

At a time when the world’s winegrowing industry is having to adapt to a number of challenges, winegrowers are wondering about the consequent changes they will have to make (grape varieties, changes in vineyard and cellar techniques). For winegrowers and consumers alike, there is also the question of how these changes will affect the taste of their wines. This research, based on the study of numerous sources and archives from the 20th century, some of which have never been published before, aims to show that, in the recent past, the winegrowing world has shown incredible resilience in the face of crises, and that the taste and perception of fine wines has changed considerably in 100 years.

Severe water stress events can induce cavitation damage by xylem embolism in grapevine, diminishing plant hydraulic conductance. This work aimed to determine the rootstock effects on 1) xylem embolism vulnerability to understand its function failure under severe drought, including segmentation processes from leaf to root; and 2) hydraulic conductance across water deficit and its recovery. For this purpose, two complementary experiments were performed in one-year-old Vitis vinifera cv. Tempranillo grafted onto two different rootstocks (110-Richter and SO4) under well-watered 12L pot conditions. In experiment 1, the water-stress induced xylem embolism was monitored in leaves and stems, above and below grafting-point, by using “Cavicam” for determining the percentage of embolized vessels (at P12, P50 and P88).