Oenological tannins to prevent Botrytis cinerea damage: reduction of laccase activity

Ovalbumin (ova), a natural clarifying protein, is particularly suitable for clarifying red wines. It helps improve the tannic and polyphenolic stability of the wine by removing the most astringent tannins and contributing to soften and refine the structure. Ova binds to suspended particles, proteins, polysaccharides, and, to a lesser extent, tannins through electrostatic and hydrophobic interactions, forming large complexes that can be removed from the wine through fining and/or filtration before bottling.

The wine industry generates each year 20 million tons of by-products. Among them grape pomaces represent a big part that can be considered as a source of potentially bioactive molecules such as polyphenols. Kombucha fermentation is an ancestral process which allow to increase the biological properties of tea by the action of a microbial consortium formed by yeasts and bacteria called scoby.

Stilbenes, a kind of non-flavonoid phenolic compounds, have been reported to be responsible for various beneficial effects. Their biological properties include antibacterial and antifungal effects, as well as cardioprotective, neuroprotective and anticancer actions (Guerrero et al. 2009).Several strategies can be used to increase stilbene content in grapes and one of them could be the use of elicitors such as methyl jasmonate. The use of this elicitor has been proven to be efficient in the production of secondary metabolites which increases the quality of wines, but its use also has some drawbacks such as its low water solubility, high volatility, and its expensive cost (Gil-Muñoz et al. 2021).

Water resource is a major limiting factor impacted by climate change that threatens grapevine production and quality. Understanding the ecophysiological mechanisms involved in the response to water deficit is crucial to select new varieties more drought tolerant. A major bottleneck that hampers such advances is the lack of methods for measuring fine functioning traits on thousands of plants as required for genetic analyses. This study aimed at investigating how water deficit affects the trade-off between carbon gains and water losses in a large panel representative of the Vitis vinifera genetic diversity. 250 genotypes were grown under 3 watering scenarios (well-watered, moderate and severe water deficit) in a high-throughput phenotyping platform.

In vineyards, management and the surrounding landscape can have different effects on spiders. In temperate regions management (organic vs. conventional) may have less strong effects than for other crops.