Ascorbic acid is a powerful and quick-acting antioxidant commonly used in white winemaking to protect against light and short aerations, such as racking and bottling. It rapidly converts dissolved oxygen into hydrogen peroxide, preventing oxidative enzymes from reacting with the wine and causing browning. The recommended way to add ascorbic acid to your wine is by stirring the appropriate amount directly into the wine just before bottling. The suggested dosage for each gallon of wine is 1/8 teaspoon of ascorbic acid. If needed, up to 1/4 teaspoon of ascorbic acid can be added per gallon of wine, but only if either 1/16 teaspoon of potassium metabisulfite or 1 Campden tablet is added at the same time.