Maturità fenolica e cellulare come metodo di valutazione dell’interazione vitigno-ambiente: il caso del Cabernet-Sauvignon

Tropical wines have been produced in the São Francisco river Valley thirty years ago, in the Northeast of Brazil. The main grape cultivar used for red tropical wines is ‘Syrah’, but wines have presented fast evolution, if they were made in the first or second semester, due to the high values of pH in grapes and wines and high climate temperatures.

Red Blotch disease caused by Grapevine red blotch-associated virus (GRBaV) is a severe concern to grape growers and winemakers in major grape-growing regions worldwide. One key aspect of all viruses, including Red Blotch, is their intimate association with cell components and anomalous structures following infection. Therefore, the objective of this study was to analyze symptomatology, vine function, fruit quality and ultrastructure of various tissues and document the relationship of ultrastructural cytopathology with the GRBaV infection in Pinot Noir and Merlot employing various microscopy techniques.

Considering that „prevention requires information”, in 2007, the european education program wine in moderation (wim) started. The common message of responsible and only moderate wine consumption is implemented in each participating country, adapted to national circumstances. In germany, besides recruiting new wim members from the wine sector, the deutsche weinakademie focusses also on information and education of future wine makers and cellar men in professional schools. The seminars cover basic information about the existing legal framework (youth protecting law, drink driving laws, etc.), the self regulation code of conduct for commercial communications (advertising) of alcoholic beverages as well as the health effects of alcoholic beverages, and of wine in particular.

Vine water status was measured on 96 plots of three vines inside a vineyard block of 0.28 ha during three years: 2003, 2004 and 2005. Three physiological indicators were implemented: stem water potential, carbon isotope discrimination measured on grape sugars at ripeness (δ13C) and canopy temperature measured by high resolution remote sensing. For stem water potential, measurements were taken on every single vine of each plot.

The composition of grape berry cell walls was studied on two grape varieties, two years and two maturation levels at the same time as the extraction of anthocyanins and tannins. The chemical composition of skins, seeds, and pulps, focused on polyphenols and polysaccharides, was compared to the chemical composition in polyphenols after extraction from the skins in model solutions or after wine making of the berries. Polyphenols were mainly characterized by UPLC-MS and HPLC-SEC. Polysaccharides were characterized by analysis of the neutral sugar compositions, and also by the CoMPP (comprehensive micropolymer profiling) analysis, a new method which targets the functional groups of cell wall polysaccharides.