Environmental and viticultural practice effects on the phenolic composition of grapes: impact on wine sensory properties

AIM. Grape seeds (Vitis vinifera) are among the main constituents of grape pomace, also exploited in ingredients for nutraceutics and cosmeceutics, particularly regarding the phenolic fraction. The macromolecules of grape/wine include polyphenols, proteins and polysaccharides.

Many volatile compounds of different chemical/biochemical origin contribute to wine aroma. Certain key ‘varietal’ aroma compounds such as methoxypyrazines are formed in the grape and appear to be only scarcely influenced by fermentation.

The color of a red wine is one of the most important parameters of its quality, giving much information on its status, such as the grape variety used or the winemaking style. As the result of a complex equilibrium between different forms of anthocyanins and polymerization reactions which occur over the course of time, color can also serve as an indication of a wines’ age. For this purpose the “chemical age” i and ii indexes have been introduced by Somers in 1977. The chemical age index i measures the color absorbance after the addition of acetaldehyde while chemical index ii provides an indication of how much of the total red pigments are resistant to SO2 bleaching.

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).

Une variable composite, dénommée Indice de Site (SI), intégrant les propriétés physiques du sol et le mésoclimat, avait été proposée pour caractériser les terroirs dans le cadre d’une étude des vignobles de Cabernet Sauvignon de Hawke’s Bay en Nouvelle Zélande.