Ascorbic acid is an antioxidant used in winemaking and brewing. It rapidly converts dissolved oxygen into hydrogen peroxide before it has a chance to react with oxidative enzymes and cause browning. For maximum effectiveness you will need to add potassium metabisulphite or campden tablets along with Ascorbic Acid. Ascorbic Acid is also known as vitamin C (the chemical, not the 90s artist.)

Packaged in a 25g bag. 

Typically in our wine stabilizer mixture we use a ratio of 80% metabisulphite and 20% ascorbic acid. For example, if we are making 100g of stabilizer - we would have 80 grams of metabisulphite and 20 grams of ascorbic acid in there.