This is an excellent ant-oxidant which helps prevent wines from oxidising during storage. Commercial winemakers also add large amounts to wines with a high acid level to induce a malo-lactic fermentation.Only small amounts are needed – 3g per gallon (1/8 teaspoon) added to the wine before bottling. You can add up to 6g (1/4 teaspoon) only if sulphite has also been added.