Sodium Metabisulphite is used as a sanitizer. Use 2 oz. of Sodium Metabisulphite per 1 gallon of water. Sodium Metabisulphite is also used as an antioxidant and bactericide. For this, use 1/4 teaspoon of Sodium Metabisulphite per 6 gallons of wine. Dissolve sulfite in warm water before adding to wine. 2 oz. container.