Technique

Impact of Oxygen on Winemaking

Oxygen’s presence or absence at the various stages of winemaking can have extraordinarily important and lasting effects on what our wines taste like. Too much and you risk oxidation damage, too little and you risk reduction stink. The effects of oxygen on wine, much more so with red wines, may be the most complex and least understood part of the winemaking process (once the grapes have left the vine) —we know a lot, but we have not solved the mystery of oxygen and wine. One note before beginning: Perhaps the most important thing I can say regarding oxygen is to always keep your carboys and tanks as full as possible. For carboys, no more than 1⁄8 inch of air space at all times. Add sanitized marbles if needed. Judging home winemaking competitions, the most common defect I’ve come across is oxidation. Most home winemakers are particularly “at risk” for oxidation damage, as the smaller volumes of wine generally react much faster to oxygen exposure than the larger volumes of commercial wineries. Let’s discuss whites and reds separately, as their handling