Identification of key-odorants in Sauternes Wines

Consumer preference favors flint-glass wine bottles over the traditional dark-colored, but it is documented that light exposure can cause white wines to produce off-aromas and change in color, and consequently da[1]mage their quality. Aim of the study was to study the white wine shelf life under the typical supermarket conditions, by recording the light and temperature exposure, the colorimetric changes, and the light-strike fault. METHODS: One pilot experiment based on two white wines and eight-time points and one kinetic experiment based on four white wines and seven-time points were designed and realized using a typical supermarket shelf for 32 and 50 days, correspondently. By installing prototype sensors at 32 points of the shelf, the temperature, UV, IR, and Visible light exposure were registered every 10 min. Approximately 600 commercial wines, bottled in flint and colored glass, were used. The colorimetric changes of the wines were registered and the light-strike fault was evaluated.

High temperatures typical of warm climates cause the colour of red wines to become increasingly unstable over time.

In Franconia, the northern part of Bavaria in Germany, climate change, visible in earlier bud break, advanced flowering and earlier grape maturity, leads to a decrease of traditionally cultivated early ripening aromatic white wine varieties as Mueller-Thurgau (30 % of the wine growing area) and Bacchus (12 %). With the predicted rise of temperature in all European wine regions the conditions for white wine grape varieties will decline and the grapes themselves will lose a part of their aromatic and fruity expression. Variety change towards the cultivation of later ripening white wine varieties is a very expensive and long-term process, and must be accompanied by special marketing efforts.

Wine dealcoholisation has been practised since the early 1900s and has gained importance due to climate change
and shifting consumer preferences for lower-alcohol beverages. Rising temperatures are accelerating grape
ripening, increasing sugar content and, consequently, raising the alcohol strength of wines.

The Rară Neagră 2.0 project aims to restore and safeguard the intra-varietal diversity of the ancient Eastern European grape variety Rară Neagră through polyclonal selection and the establishment of a certified genetic conservatory.