Nisin is a natural, toxicologically safe, antibacterial food preservative. It is produced by certain strains of the food-grade lactic acid bacterium Lactococcus lactis subsp. lactis. Nisin exhibits antimicrobial activity towards a wide range of Gram positive bacteria, and is particularly effective against spores. Nisin was first introduced commercially as a food preservative in the UK. First established use was as a preservative in processed cheese products and since then numerous other applications in foods and beverages have been identified. In the U.S., Nisin was awarded the Generally Regarded as Safe (GRAS) designation in the U.S. Federal Register of April, 1988 and is approved as a natural food preservative in the United States. Nisin is used to inhibit outgrowth of Clostridium botulinum spores and toxin formation in pasteurized process cheese spreads with fruits, vegetables or meats. Nisin is also approved for liquid egg products, dressings, and sauces. In other countries it is also used in fresh and recombined milk, fermented beverages like beer, canned foods, frozen desserts, and high moisture/reduced fat foods. Nisin is considered effective at controlling a wide range of gram-positive organisms including: Listeria, enterococcus, Bacillus sporothermodurans, and clostridium.