The wine microbial consortium: a real terroir characteristic

The gustatory balance of dry wines is centered on three flavors, sourness, bitterness and sweetness. Even if certain compounds were already identified as contributing to sweetness, some taste modifications remain largely unexplained1,2. Some empirical observations combined with sensory analyzes have shown that an increase of wine sweetness occurs during post-fermentation maceration³. This step is a key stage of red winemaking during which the juice is left in contact with the marc, that contains the solid parts of the grape (seeds, skins and sometimes stems). This work aimed to identify a new taste-active compound that contributes to this gain of sweetness.

Oxidative stability is a critical factor in wine shelf-life. SO₂ is commonly added to wine due to its strong antioxidant activity, although there is a general push to reduce SO₂ use in vinification.

To characterize in depth the enological productions according to the origin territories and to provide modern tools for the qualitative raising of the assorted typologies of wine produced, Veneto Agricoltura (the regional agency for the agriculture, forestry and food industry development), the Regional Government of Veneto (north-eastern Italy) and various Consortia of Producers have undertaken since 2002 a systematic classification of the viticultural territories by agro-ecological zoning to achieve a strategic project aimed to set Veneto as the first Italian region to have completed in a systematic and scientifically rigorous way the zoning of most of its Denomination of Origin areas.

The wide ampelographic heritage of the Italian wine grape varieties represents a richness in terms of biodiversity and potential market value.

Wine grapes have the ability to accumulate high amounts of hexoses (glucose and fructose), which is considered one of the main processes occurring during the ripening stage. Sugar accumulation dynamics respond to genetic, environmental and vineyard management factors, with a changing climate leading to advanced and faster sugar accumulation worldwide. Research on mitigation techniques to this phenomenon is ongoing, with the largest focus being vineyard techniques to delay sugar accumulation. Breeding represents another powerful tool to address the issue of high sugar concentration at harvest, since historical trends of selecting best sugar-accumulators may be inverted to breed varieties that accumulate diminished concentrations of hexoses while maintaining optimal acidity, color, mouthfeel and aroma compounds.