How will the use of a nitrogen generator at 98% to 99.5% affect the Dissolved Oxygen pickup of wine?
Winemakers go to great lengths to minimize the DO pickup of their wine. Oxygen in wine can cause discoloration and impact taste and aroma. According to
Wines and Vines exposure to air is a primary culprit in
chemical oxidation of wine especially after primary fermentation and during the later stages of wine production. Wine is particularly vulnerable to
excess oxygen during transport from tanks, barrels and in the final bottling process. It is important to purge all filters, transport lines and containers
with an inert gas like nitrogen. The headspace of the bottle should also be filled with nitrogen to eliminate the chance of oxygen pick up after bottling.
Using nitrogen as the inert gas, the question arises as to how pure the nitrogen needs to be to minimize the DO pickup.
One of our winery customers conducted an experiment using a McBrady Orbital bottler but used air instead
of nitrogen. The experiment fount that DO pickup in the wine was 9.7 ppm. We know that air contains 20.9% oxygen or 209,000 ppm of oxygen. Therefore,
exposure to 209,000 ppm of oxygen gives 9.7% DO. With this information and by using ratios, we can determine what the DO levels would be at different
Therefore, wineries can be confident that by using a Balston Nitrogen generator at purities between 98-99.5% will keep their DO levels in their finished
product below 1 ppm. In actual practice at hundreds of wineries around the world, Parker’s customers achieve even better results that what the mathematical
treatment above would predict. One site even ran at Nitrogen purities at just 95% using a Parker generator and the DO pickup was as good as liquid
nitrogen with a purity of >99.99%.