Oxidation is the result of too much air contact during racking, storing and bottling and/or insufficient sulfite. The odour is primarily due to acetaldehyde, the oxidation product of ethanol.
Without sulfite, colour and aroma compounds react with oxygen. With oxidation the fruity aroma disappears and is replaced by an “aldehyde” or “sherry” aroma. As oxidation proceeds, red wines change from bright red to brick red and then brown. White wines change from yellow to gold to brown.
Oxidation that takes place extremely gradually, such as during aging, adds complexity to the wine and is considered desirable. In white wines the threshold for acetaldehyde is as low as 30-40 mg/L.
Please use our sealed primary, our quality corks and our vacuuvin system to remove CO2 gas from your wines in order to avoid problematic oxidation. We guarantee all our wine and beer kits if you use our equipment and corks and caps.