Bio-protection by one strain of M. Pulcherrima: microbiological and chemical impacts in red wines

Over the last years, due to climate change, several red wines, such as the Sangiovese wines, have been often subjected to loss of clarity due to the formation of deposits of fine needle-shaped crystals. This phenomenon turned out to be due to an excess of quercetin (Q) and its glycosides (Q-Gs) in wines. These compounds are synthesized to a large extent when grapes are excessively exposed to UVB radiations in vineyards[1]. Unfortunately, it is not easy to predict the degree of Q precipitation because its solubility strongly depends on the wine and matrix composition[2].

Goriška Brda est la région viticole située le plus à l’ouest de la Slovénie, attenante au Collio d’Italie. Goriška Brda (2020 ha de vignobles) a une longue tradition d’élevage viticole. La proximité de la mer Adriatique (Golfe de Trieste) au sud-ouest et des Alpes Juliennes au nord contribue à un climat caractéristique et unique qui influe sur la croissance et la fertilité de la vigne. La constitution des sols, un climat typique et un relief mouvementé provoquent des différences dans la production du raisin, sa quantité et sa qualité. L’utilisation du zonage ou du microzonage permettraient d’atténuer les influences des facteurs climatiques et du sol sur la production de la vigne ou d’en profiter. Pour évaluer la signification des différents facteurs, nous avons résumé et réuni les modèles de différents auteurs.

The timing of phenology is critical if grape quality potential is to be optimized. Phenological process based models are used to predict phenology. In this study, three different models

Canopy-management practices are applied in viticulture to improve berries composition and quality, having a great impact on primary and secondary grape metabolism. Among these techniques, cluster zone leaf removal (defoliation) is widely used to manage air circulation, temperature and light radiation of grape bunches and close environment. Since volatiles are quantitatively and qualitatively influenced by the degree of fruit ripeness, the level of solar exposure, and the thermal environment in which grapes ripen, leaf removal has been shown to affect volatile composition of grape berries [1].

An integrated terroir characterization is currently realized in the French northern vineyard: “Anjou”. The concept of Basic Terroir Unit (B.T.U.) and its associated ground model “Rock, Alteration, Alterite” are used in this characterization. This work is coupled to a viticultural survey, based on parcels.