Influence Of Phytosterols And Ergosterol On Wine Alcoholic Fermentation For Saccharomyces Cerevisiae Strains

Elemental sulfur is commonly used in vineyards as a fungicide to prevent diseases and protect grapevines.1 The challenges of climate change are intensifying disease pressure, further increasing the reliance on sulfur use. Understanding the range of potential impacts of residual sulfur during the winemaking process is becoming increasingly important.

Although vitamins stand as major actors to yeasts prime metabolic pathways, their significance in oenology and winemaking remains rather obscure nowadays, having been mostly unexplored for several decades.

Nous savons tous très bien qu’on a assisté au cours de ces dix dernières années à une éclosion soudaine de recherches sur le zonage viti-vinicole qui, à partir par exemple du modèle du concept de “terroir”, se sont de plus en plus enrichies en passant aux “Unités ou Systèmes de Transformation” (UTTE) et “Valorisation” (UTCE) pour terminer avec les “Systèmes productifs globaux du Territoire” (UTB) comprenant en filière les aspects existentiels (UTBES), sociaux (UTBSO) et économiques (UTBEC) hypothisés dans le “GRANDE ZONAZIONE: Grand zonage” (MORLAT R., 1996, CARBONNEAU A., 1996, TOUZARD J.M. 1998, CARBONNEAU A., CARGNELLO G., 1996, 1998, CARGNELLO G., 1994, 1995, 1996, 1998, 1999, 2001, -MILOTIC A., CARGNELLO G., PERSURIC G., 1999, PERSURIC G., STAYER M., CARGNELLO G., 2000, MILOTIC A., OPLANIC M., CARGNELLO G., PERSURIC G., 2000).

The objective of this investigation was to verify usefulness of proximal sensing technology and unmanned aerial vehicles (UAVs) for mapping variables e.g., vine size (potential vigor), soil and vine water status, yield, fruit composition, and virus incidence in vineyards.

A part, at least, of red wines fruity expression may be explained by perceptive interactions involving particularly various substituted ethyl esters and acetates present at concentration far below their olfactory threshold, specifically thanks to synergistic effects. Wine sensory perception is directly linked to the stimulation of the taster at the level of olfactory epithelium by volatiles. These compounds are liberated from the matrix to the atmosphere, and will then be smelt. From a physico-chemical point of view, these volatiles ability to be released may be evaluated by their partition coefficients, which correspond to the volatile concentration ratio between the liquid and gas phase. Our goal is, through these coefficients determination, to assess if volatile matrix composition is able to impact the volatility of some compounds, and then explain sensory perception, i.eto evaluate what is called the pre-sensorial level impact.