Application of fluorescence spectroscopy with multivariate analysis for authentication of Shiraz wines from different regions

A 3-year study was conducted in the Vaud vineyard (Switzerland) to evaluate the effects of « terroir » on the ecophysiology and fruit compostion of Vitis vinifera L. cv.

Pratiquement tout le territoire d’Istrie possède les bonnes conditions naturelles pour la viticulture, laquelle dans ce lieu a une tradition millénaire. La viticulture était et reste toujours la plus importante branche de production agraire et d’économie. Les sites viticoles en Istrie sont caractérisés par des diverses conditions naturelles.

Oenological tannins (OETs) are an alternative to sulphur dioxide due to their antioxidant and antioxidase properties in the early phase of winemaking [1,2].

The advance in maturation of wine grapes is an important climate change risk related effect that could affect warm regions like Portuguese Douro Wine Region. Indeed, the climate analysis over the past years registered a decrease in the precipitation, significant higher average temperatures, and a more frequent occurrence of extreme weather events, including heat waves. In these conditions the length from anthesis until maturation is shortened and the uncoupling of technical and phenolic maturity results in berries with higher sugar concentration (and lower acidity), but lower anthocyanins, tannins, and total phenolic concentration, which produce unbalanced wines.
In this work, an innovative strategy of crop forcing, based on forcing vine regrowth after a second pruning of green shoots, was tested, aimed at delaying ripening until the temperature becomes lower and, therefore, preventing acidity loss and increasing anthocyanin-to-sugar ratio. The experiments were conducted in 2019 and 2020 in a commercial vineyard of ‘Touriga Nacional’ located in the Douro Region. Crop forcing was conducted 15 (CF1) to 30 (CF2) days after fruit set. Vines pruned with conventional methods were used as control (CF0). Results confirmed that fruit ripening was shifted from the hot season (August/September), until a cooler period (October through early-November). At harvest, grapevine berries from CF1 and CF2 presented lower pH and higher acidity, than control, with no significant differences in colour intensity and phenolic levels composition. Sugar content was lower in CF2-treated vines in both seasons. However, in CF-treated vines the number and size of clusters were significantly lower (up to 88% reduction) than in control plants. A metabolomics analysis of mature berries from CF-treated vines and control is underway. Crop forcing was indeed effective in producing a more balance berry composition but severely reduced grapevine yield,

Aluminum is a particularly interesting material for packaging because it is environmentally sustainable, lighter than standard glass bottles, and protective against light radiation [1].