Campden Tablets (100's) contain potassium metabisulphite and are used at the end of fermentation and before bottling to prevent oxidation and bacterial contamination. They inhibit the growth of wild yeasts and bacteria that can cause off-flavours or spoilage, and can also be used as a sterilising agent for equipment.
Use 1 tablet per 4.5 litres before bottling wine or cider to stabilise the finished product. Also useful for neutralising chlorine in tap water before brewing (1 crushed tablet per 23 litres). Works alongside Bentonite and Sodium Metabisulphite for complete wine making sanitation. See also: Young's Steriliser for equipment.