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Oidio: Oidium
A fungal disease, also known as powdery mildew. Like many vine diseases it thrives in damp conditions. It results in a reduction in quality and yields, but fortunately may be controlled with the application of sulphur, a practice permitted for even organic and biodynamic winemakers.

Ossidazione: Oxidation
The degrading action of oxygen on a wine (or any other substance) is known as oxidation. Hence exposure of the wine to oxygen in the winery is carefully controlled, although not necessarily completely avoided. Exposure to oxygen during racking and ageing in barrel can be of benefit to the wine. Once a bottle of wine has been opened for some time, or if oxygen has seeped past a faulty cork, the oxidised wine will taste off.