Sustainable fertilisation of the vineyard in Galicia (Spain)

Lugana Protected Designation of Origin (PDO) wines are made from Turbiana grapes. The aroma of Lugana wines results from the combined contribution of esters, terpenes, norisprenoids, sulfur compounds and the benzenoid methyl salicylate. This study aims to investigate how volatile aroma compounds are affected by different nitrogen supplies and yeast strains. Wines were produced with a standard protocol with 2021 Turbiana grapes with two different yeasts Zymaflore Delta e Zymaflore X5 (Laffort, France).During the alcoholic fermentation of the must, when H2S appeared, additions of various nitrogen supply were made: inorganic nitrogen, organic nitrogen, a mix of inorganic and organic nitrogen and organic nitrogen with an addition of pure methionine. During wine fermentation, a daily measurement of hydrogen sulfide was carried out.

Phenolic compounds play a central role in sensory characteristics of wine, such as colour, mouthfeel, flavour and determine its shelf life. Furthermore, the major non-enzymatic wine oxidation process is due to the catalytic oxidation of phenols in quinones. Due their importance, during the years have been developed different analytical methods to monitor the concentration of phenols in wine, such as Folin-Ciocalteu method, spectrophotometric techniques and HPLC. These methods can also be used to follow some oxidation-related chemical transformations.

Vitis vinifera is one of the most diffused grapevines over the word and it is the raw material for high quality wines production. The availability of more resistant interspecific hybrid vine varieties, developed from crosses between Vitis vinifera and other Vitis species, has generating much interest, also due to the low environmental effect of production. However, hybrid grape wine composition and varietal differences between interspecific hybrids are not well defined. Different studies revealed that wine consumption has health effects due to its high content of antioxidants, as phenolic compounds. In particular, simple phenols are appreciated not only for their physiological health benefits, including antioxidant, anti-inflammatory and cardioprotective effects, but also because they affect wines organoleptic profile and have a significant role in defining their nutritional characteristics.

The main phenological stages (budburst, flowering, veraison, and ripeness) and the fruit composition of 34 Spanish minority varieties were studied to determine their cultivation potential and help winegrowers adapt their production systems to climate change conditions. In total, 4 control cultivars, and 30 minority varieties from central Spain were studied during a period of 3 campaigns, in the ampelographic collection “El Encín”, in Alcalá de Henares, Madrid. Agronomic and oenological characteristics such as yield, and total soluble solids concentration have been monitored.

Les études d’impact du climat sur la vigne nécessite de descendre à des échelles très fines car les facteurs climatiques sont tributaires de la topographie, la végétation, les expositions … Dans le cadre du programme ANR-JC Terviclim, 22 capteurs ont été installés dans les vignobles des Coteaux du Layon afin de caractériser le climat particulier de ces terroirs. L’analyse des températures montre de fortes disparités entre les data loggers et pourtant situés parfois sur les mêmes parcelles ou sur des parcelles voisines. Les indices bioclimatiques tels les degrés jours sont également contrastés suivant la situation des capteurs sur les coteaux.