Acetaldehyde

Acetaldehyde meaning in wine

Acetaldehyde is an aldehyde formed in wine during fermentation and especially through oxidation of ethanol. At low or controlled levels it can contribute nutty, bruised-apple, or intentionally sherry-like notes, but excessive acetaldehyde is usually a fault that makes table wine smell flat, oxidized, or stale. It is also an intermediate in human alcohol metabolism, but for wine tasting and winemaking the main relevance is aroma, oxidation management, and the protection provided by sound cellar practice and sulfur dioxide.