Using GIS to assess the terroir potential of an Oregon viticultural region

Climate is an important component or determinant of terroir, especially at the regional level. One can define three levels of terroir. These are the macro– or regional scale, which applies over tens of kilometres of the landscape. The second level is the meso- scale, which applies over kilometres or hundreds of meters, at the individual vineyard scale.

Global warming is accelerating grape ripening, leading to unbalanced wines from fruit with high sugar content but poor aroma and colour development. Reducing the size of the photosynthetic apparatus after veraison has been shown to delay technological ripeness in cool climates, but methods have not been tested in areas with high irradiance and temperature where fruit exposure could have disastrous effects on berry composition. In this Cabernet-Sauvignon trial, we compared the application of an antitranspirant (pinolene), to severe canopy topping and above bunch zone leaf removal, all performed at mid-ripening, with an untouched control. We monitored the vines weekly by measuring stem water potential, gas exchange, fruit zone light exposure. We sampled berries to measure berry weight, total soluble solids, pH, titratable acidity, and the anthocyanin profile. At harvest, we assessed yield components, measured carbon isotope discrimination, rated sunburn on clusters, and produced experimental wines. We submitted harvest samples to metabolomic profiling through PFP-Q Exactive MS/MS and wines to sensory analysis. Application of the antitranspirant significantly reduced stomatal conductance and assimilation rate but did not affect the stem water potential. Inversely, leaf removal and topping increased water potential but did not affect leaf gas exchange. The late topping was the only treatment able to decrease sugar content (up to 2Bx), increase titratable acidity and pH, and improve anthocyanin content because of lower degradation of di-hydroxylated forms. Late leaf removal above the bunch zone increased lightning conditions in the canopy and produced the most significant damage on fruits. Yield components were not affected. This work suggests that late-season canopy management can effectively control ripening speeds and improve grapes and wines. Still, the effect on grape exposure in a critical time must be well balanced to avoid problems with the appropriate technique.

​For several years, the chemistry of taste has aroused high interest both from academics and industrials. Plant kingdom is a rich and reliable source of new taste-active compounds. Many sweet, bitter or sour molecules have been identified in various plants [1]. They belong to diverse chemical families and their sensory properties are strongly affected by slight structural modifications. As a consequence, the investigation of natural taste-active products in a given matrix appears as a major challenge for chemists. Such studies are particularly relevant in oenology since they allow a better understanding of wine and spirit taste.

Adrenaline (epinephrine) belongs to catecholamine class. It is a neurotransmitter and both a hormone which is released by the sympathetic nervous system and adrenal medulla in response to a range of stresses in order to regulate blood pressure, cardiac stimulation, relaxation of smooth muscles and other physiological processes. Adrenaline exhibits an effective antioxidant capacity (1). However, adrenalin is capable to auto-oxidation and in this case it generates toxic reactive oxygen intermediates and adrenochrome. Under in vitro conditions, auto-oxidation of adrenaline occurs in an alkaline medium (2).

The aim of this work was to characterize the aromatic profile of white and rosé base wines for the elaboration of sparkling wines from seven autochthonous grape varieties of Castilla y León. The ‘Albarín’, ‘Godello’ and ‘Verdejo’ white grape cultivars contribute with more fruity notes than the ‘Viura’ and ‘Malvasía’ cultivars; and ‘Prieto picudo’ coloured grape cultivar has more fruity character than ‘Garnacha’.