Botrytis cinerea is a fungus that affects grapevines and can develop either as destructive grey rot or as beneficial noble rot, depending on vineyard conditions. Under alternating moisture and dry weather, it can dehydrate berries, concentrate sugars and acids, and intensify aromatic compounds.
In winemaking, noble rot is central to some of the world’s great sweet wines, including Sauternes, Tokaji Aszú, and selected German and Austrian dessert wines. Its influence can produce flavors of honey, apricot, saffron, marmalade, ginger, and dried fruit, while preserving the acidity needed to balance extreme sweetness.