NIR based sensometric approach for consumer preference evaluation

Aroma is one of the most important attributes that determine consumer’s perception of the sensory quality of wine and varietal typicity.

In wine growing regions around the world, climate change has the potential to affect vine transpiration and overall vineyard water use due to related changes in atmospheric demand and soil water deficits. Grapevines control their transpiration in response to a changing environment by regulating conductance of water through the soil-plant-atmosphere continuum. Most vineyard water use models currently estimate vine transpiration by applying generic crop coefficients to estimates of reference evapotranspiration, but this does not account for changes in vine conductance associated with water stress, nor differences thought to exist between varieties. The response of bulk stomatal conductance to daily weather variability and seasonal drought stress was studied on Cabernet-Sauvignon, Merlot, Tempranillo, Ugni blanc, and Semillon vines in a non-irrigated vineyard in Bordeaux France. Whole vine sap flow, temperature and humidity in the vine canopy, and net radiation absorbed by the vine canopy were measured on 15-minute intervals from early July through mid-September 2020, together with periodic measurement of leaf area, canopy porosity, and predawn leaf water potential. From this data, bulk stomatal conductance was calculated on 15-minute intervals, and multiple regression analysis was performed to identify key variables and their relative effect on conductance. Attention was focused on addressing multicollinearity and time-dependency in the explanatory variables and developing regression models that were readily interpretable. Variability of vapor pressure deficit over the day, and predawn water potential over the season explained much of the variability in conductance, with relative differences in response coefficients observed across the five varieties. By characterizing this conductance response, the dynamics of vine transpiration can be better parameterized in vineyard water use modeling of current and future climate scenarios.

Le climat a de fortes implications sur le bon fonctionnement physiologique de la vigne et a besoin d’être quantifié afin de déterminer l’aptitude des régions à la culture de la vigne. Une méthode, qui pourrait éventuellement servir à prévoir l’aptitude des régions à la culture de la vigne, est proposée.

Following its approval in 2013 by Agroscope, Divico became the first interspecific grape variety in Switzerland with high resistance to downy mildew (Plasmopara viticola) and grey rot (Botrytis cinerea), and medium resistance to powdery mildew (Uncinula nectator). Extremely riche in color, Divico grapes showed great enological potential to different styles of wine. Quickly, many wine growers were interested in planting this promising variety. Many of its potential are to be explored in the coming years.

The variety Aragonez (sin. Tempranillo), recently introduced in the San Francisco Valley (9º02′ S; 40º11′ W) has revealed an excellent adaptation, with high potential of quality and yield, even without clonal material.