Influence of the year and the environmental factors on condensed tannins from Cabernet franc grapes

In recent years there has been a growth in interest and number of research studies regarding the application of remote optical and thermal sensing by unmanned aerial vehicle (UAV) in agriculture and viticulture. Many papers report on the use of images to map or estimate the growth and water status of plants, or the heterogeneity of different parcels. Most often, NDVI or other similar indices are used.

This study aimed to validate a protocol and compare metrics for evaluating drought tolerance in two Vitis vinifera grapevine cultivars under field conditions. Various metrics were calculated to represent the physiological responses of plants to progressive water deficit. Data were collected from Sauvignon Blanc and Chardonnay plants subjected to three irrigation levels during the 2022-2023 season, along with data from three previous seasons. Hydro-escape areas were used to assess the plant’s ability to reduce water potential with decreasing soil water availability.

In France, the definition of appellations of origins is entrusted to the Institut National des Appellations d’Origine. (‘NAO). With the increase in price of appellations of origin vine­yards and considering the interests at stake, Institut National des Appellations d’Origine and the Institut National de Recherche Agronomique (INRA) established a work group in 1993 in order to study the “terroir-wine” relationship as precisely as possible, taking into account the knowledge acquired by researchers of the INRA and the experience in the field of the agents of the INAO.

Il Nebbiolo, uno dei vitigni più rappresentativi della viticoltura piemontese. é caratterizzato da una maturazione tardiva, una elevata vigoria e una bassa fertilità basale. La sua popolazione inoltre presenta una tale variabilità morfologica che é consuetudine suddividere il vitigno in diverse sottovarietà (Lampia, Rosé, Michet, Balla per citare solo quelle dell’areale albese) ognuna con presunte distinte caratteristiche morfologiche e produttive.

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.