Proteomic profiling of grape berry presenting early loss of mesocarp cell vitality

“Vinum debet esse naturale ex genimine vitis et non corruptum”. The Eucharistic wine must be made with pure grapes that must not be contaminated in any way. This is how wine was born in the monastery of the Augustinians, and that is how the genetic improvement of grapevine implemented over the decades at the Agricultural Institute of San Michele all’Adige (since 1874; Trentino – Italy) has been oriented to make the cultivation of grapes always more sustainable. This concept is still current and meets the worldwide urgent need of reducing the use of chemicals, under a climate crisis scenario. Since the beginning of the twentieth century, the varieties introduced in Trentino and the new cultivars produced by pioneer breeders have already embraced the principle of sustainable viticulture.

Most oxidation reactions in wine require iron as a catalyst. The iron content of wine has decreased greatly in recent decades due to the use of low or no release cellar materials; however, in some cases it is still necessary to adopt winemaking practices to remove excess iron from wine, prevent its oxidation, and be able to reduce the addition of sulfur dioxide and other antioxidants.

Brettanomyces is a world-renowned yeast that negatively impacts the chemical composition of wines through the production of metabolites that negatively impact the sensory properties of the final product. Its resilience in wine conditions and ability to produce off-flavors make it a challenge for winemakers. Currently, the primary control technique involves adding sulfur dioxide (SO2); however, some Brettanomyces strains are developing resistance to this preservative agent. [1] Therefore, new management strategies are necessary to control this spoilage yeast.

Esters play an essential role in the young white wines’ fruity expression, particularly the groups of ethyl esters of fatty acids (EEFAs) and higher alcohol acetates (HAAs) [1]. However, generally, these groups of esters decrease relatively fast during the first two years of ageing [1, 2].

Unlike table wines, Madeira Wine (MW,17-22% ABV) benefits from a long aging period under thermo-oxidative aging conditions, during which it gains its unique and complex flavour. A broad study is ongoing and aims to assess if the differences in the storage conditions impact significantly the evolution of MWs during canteiro aging. Considering that polyphenols have a significant role in the wine aging, we intended to appraise if there are significant differences in the evolution trends of polyphenols of MWs aging in different cellars under canteiro. Different MWs were aged into brand-new oak casks in two different wine cellars, one in Funchal (B) and other in Caniçal (Z). Temperature and humidity data were sensor recorded. RP-HPLC-DAD was used to perform the identification and quantification of polyphenols [1]. CIELab parameters were also assessed, using an UV-Vis spectrophotometer.