Characterizing the molecular basis of the differences in aromatic precursors found in commercial clones of Vitis vinifera cv. Tannat

Ecological resources represent vegetation factors, or even production factors, in quantitative expression. These, used by plants, transformed and organized according to their genetic program, become the material components of biomass. Subsequently, the ecological resources can be used as synthetic indicators of the ecological supply, necessary for the analysis of favorability for the understanding of ecosystems.

Temperature extremes affect grapevine physiology, as well as grape quality and production. In most grape growing regions, frost or heat wave events are rare and as such conducting a risk analysis using robust statistics makes the use of long term daily data necessary.

Pruning vine-shoots are a viticulture waste that have been traditionally poorly exploited in relation to its chemical minority composition related to phenolic and volatile compounds. In this line, toasted vine-shoots supposes a proposal of enological tool to use to modulate the chemical and sensorial profile of wines. From a phenolic point of view, when vine-shoots are used during winemaking mainly influence to increase the flavanols and stilbenes content, mostly trans-resveratrol, as also an increasing in the sweet tannins and decreasing the green character and total anthocyanins, changing the violet for garnet colour.

The use of oenological additives is becoming a common practice due to the technological and sensory properties they provide to the wines. However, the number of studies focused on the impact that these additives might induce on wine flavor perception during wine tasting is still quite scarce. The aim of this work was to evaluate the effect of three different types of common oenological additives: two oenotannins (ellagitannin and gallotannin) and a commercial preparation of yeast mannoproteins on the long-lasting flavor perception (aroma and astringency).

Wine quality depends on grape biochemical constituents, including sugars, organic acids, amino acids, and bound and free aroma compounds, which are influenced by vineyard location and environmental factors such as temperature and precipitation [1].