Avoiding Oxidation

I attended a session at the Eastern Winery Exposition titled Avoiding Oxidation in Small Wineries. Tom Payette was the presenter and used PowerPoint slides during the presentation. He mentioned several variables that influence oxygen reacting with the wine. Some variables can be controlled while other can not. Tom was especially wary of the use of variable capacity tanks, a popular type of tank used in many small wineries. Most of the problems he was called on to investigate and help with were due to variable capacity tanks. For the short term, these tanks are great. For the long term storage they present challenges for the winemaker. Tom mentioned the importance of controlling the surface area in carboys, barrels and tanks. Topping off gases are a temporary solution to helping reduce oxidation; however, they are not as good as a full tank.

The oxidation challenge is not all doom and gloom. There are some producers that want to create oxidized wines and have a market for them. At some points in the winemaking process, oxygen is a good thing. During fermentation, oxygen is a nutrient for yeasts. In aging, oxygen can soften tannins.

The winemaker can check hoses to see if there are leaks, and reduce the container’s surface area where oxygen can contact the wine. Winemakers should also be cognizant of the potential for wines to become oxidized at different parts of the winemaking process.

Cheers,
Terry