Sulfur-containing preservatives which prevent food spoilage and discoloration by browning. The sulfiting agents used by the food industry are sulfur dioxide, sodium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite and potassium metabisulfite. They are used to preserve foods such as processed potatoes, dried fruits, dehydrated vegetables, shellfish and other seafood, and as a bleaching agent for food starches, among other uses. They are also used in medical drugs (both prescription and over-the-counter) to help keep them stable and potent for a longer period of time. For more information, visit The Sulfite Backgrounder.