What happens with the glutathione during winemaking and the storage of the wine?

The growing region of Barolo DOCG certified wines is topographically complex. The region is famous for this complexity and for the associated terroir driven Nebbiolo grapes and wines derived distinctly from this varietal. Although it is recognized that the Barolo area is unusual topographically and it is assumed that this unusual topography lends to the inherit terroir, the specifics of this relationship are less well defined.

Abstract In this work the effects of early leaf removal performed manually at preflowering phenological stage, on the volatile composition of Tempranillo (Vitis vinifera L.) wines were studied. From 2009-2011 vintages 34 wine volatile compounds were identified and quantified by gas chromatography-mass spectrometry (GC-MS) where early leaf removal only modified 25 of them. The total C6 compounds, acetates and volatiles acids (with exception of isobutyric acid) were affected by defoliation, whereas alcohols and esters showed a minor effect. Furthermore the vintage effect also was shown.

The jurist feels like an intruder when talking about terroirs. He looks at the press and tries to understand. We can read there about the cooking festival of May 30, 1996 which “..highlights products whose quality depends on a region”, that Camembert du pays d’Auge is the only one to be protected, I was thinking of camembert from Normandy, that 80% of Greek feta is made in the Netherlands, I thought it was in Denmark, and that the European Community protects geographical indications of IGP origin, probably a new category replacing the indications protected areas (1). I also learned that distributors are asking for more local products because “they come to confuse the cards in the part engaged with the big brands”. Carrefour has its “Terroirs and drawers”, Prisunic its “Vent d’Ouest”, Intermarché “Les bouquets du terroir”, Monoprix “Les terroirs de France” (2), Promodés and its brand “Reflets de France” for the “Continent” hypermarkets (3). At the same time it is asserted that “The term is a mere common noun. Unprotectable and therefore unprotected” (4).

Saccharomyces cerevisiae is the most commonly used yeast species in winemaking. The recent research showed that non-Saccharomyces yeasts as fermentation starters show numerous beneficial features and can be utilized to reduce wine alcoholic strength, regulate acidity, serve as bioprotectants, and finally improve wine aromatic complexity. The majority of published studies on this topic investigated the influence of sequential or co-inoculations of non-Saccharomyces and S. cerevisiae yeasts on the aroma of final wine.

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.