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

Nella realtà viticola Italiana il Prosecco è uno degli esempi più evidenti di un percorso storico che ha saputo valorizzare lo stretto legame tra vitigno e territorio d’origine.

Viticulture is facing two major challenges – climate change and agroecological transition. The soil plays a pivotal role in these transition processes. Therefore, soil quality and adequate soil management are key levers for an ecologically and economically sustainable viticulture. Over the last 15 years, numerous studies evidenced strong effects of viticultural practices on the soil physical, chemical and biological quality. However, to date a global analysis providing a comprehensive overview of the ecological impacts of viticultural practices on soil biological quality is missing.

Wine quality is defined by sensory and physico-chemical characteristics. In particular, sensory features are very important since they strongly condition wine acceptability by consumers. However, the evaluation of sensory quality can be subjective, unless performed by a tasting panel of experienced tasters. Therefore, it is of great relevance to establish relationships between objective chemical parameters and sensory perceptions, even though the complexity of wine composition makes it difficult. In this sense, more reliable relationships can be found for a particular wine typology or variety. The present study aimed to predict the perceived sensory quality from the physico-chemical parameters of ‘Barbera d’Asti’ DOCG red wines (Italy).

Polyphenols are present in a wide variety of plants and foods such as tea, cacao and grape1. An important sub-class of these compounds is the flavanols present in grapes and wines as monomers (e.g (+)-catechin or (-)-epicatechin), or polymers also called condensed tannins or proanthocyanidins. They have important antioxidant properties2 but their biosynthesis remains partly unknown. Some recent studies have focused on the role of glycosylated intermediates that are involved in the transport of the monomers and may serve as precursors in the polymerization mechanism3, 4. The global objective of this work is to identify flavanol glycosides in grapes or wines, describe their structure and determine their abundance during grape development and in wine.

Pour son travail de cartographie et de caractérisation des terroirs, la Cellule Terroirs Viticoles utilise la méthode développée par l’Unité Vigne et Vin du Centre INRA d’Angers. Cette méthode reconnue au niveau international est appliquée dans les vignobles du Val de Loire à l’échelle du 1/10 000e et est valorisée par des éditions d’Atlas Viticoles à destination des viticulteurs et des organismes techniques.