Combination of NIR multispectral information acquired from a ground moving vehicle with AI methods to assess the vine water status in a Tempranillo (Vitis vinifera L.) commercial vineyard

The irrigation water management in the vineyard is a crucial aspect to obtain sustainable quality production over time. Previous studies have set the water requirements to be applied in the vineyard at 30 % of the reference evapotranspiration (ET0), although there are no studies that settle the effects of the frequency of irrigation application on red varieties in Spain. The present study contemplates the application of deficit irrigation (30 % ET0) applying a weekly dose in a single irrigation (T07) or in two irrigation events (T03) per week. The study has been carried out in 2021-2022 with four red varieties in different Spanish wine regions: Garnacha Tinta (Badajoz), Tempranillo (Valladolid), Syrah (Albacete) and Mencía (Lugo). The effects of irrigation frequency on must volatile composition have been evaluated through GC-MS.

The Appellation d’Origine Contrôlée area of ​​Cahors (Lot) covers an area of ​​21,700 ha, spread over 45 municipalities, of which only 4,300 are planted with vines. The main grape variety of this AOC is the Cot noir which represents 70% of the grape varieties, thus giving their typicality to the wines of this region; but despite this importance, to our knowledge, its physiology has remained relatively unstudied.

Aims: Agroscope investigated the efficiency of nitrogen fertilization via foliar urea application at veraison with the aim of raising the YAN (yeast assimilable nitrogen) content in the musts. The observations were conducted on the white grapevine cultivar Doral (Chasselas x Chardonnay) in several pedoclimatic conditions of the Leman wine region, Switzerland, in the years 2012 and 2013. Knowing that the YAN in must plays a key role in wine quality, the aim was finding the main parameters affecting the final YAN level in order to better control them.

A set of Syrah plots covering a wide range of terroirs distributed in the vineyards of the Rhone Valley and the Mediterranean South is examined through their oenological and sensory characteristics. The multidimensional analysis of data leads to the following groupings: (1) A group of unstructured wines with a simple aromatic profile dominated by fruity-floral notes; they come from plots where the ripening conditions have been disturbed by unfavorable climatic conditions, or an excess harvest.

White wine protein haze can be prevented by removing the grape juice proteins, currently achieved by bentonite addition. To avoid wine volume loss and to minimizes aroma stripping, degrading haze-forming proteins in wine with proteases is a particularly interesting alternative to bentonite. In the present study, two fungal proteases treatments combined with different heating (50, 60, 72 °C) + refreshing steps, were applied on Gewürztraminer grape juice, and compared to bentonite treatments. The impact of these 19 treatments on the wine haze risks was determined by using two heat tests at 50 °C (heating during 30 to 120 min) and 80 °C (heating during 5 to 60 min). The protein contents and compositions were also estimated using the SDS-PAGE + densitometric integration techniques.