Pink slime (also known as lean finely textured beef or LFTB, finely textured beef, and boneless lean beef trimmings or BLBT ) is a meat by-product used as a food additive to ground beef and beef-based processed meats, as a filler, or to reduce the overall fat content of ground beef. In the production process, heat and centrifuges remove fat from the meat in beef trimmings. The resulting paste is exposed to ammonia gas or citric acid to kill bacteria. In 2001, the United States Department of Agriculture (USDA) approved the product for limited human consumption. LFTB prepared using ammonia gas is banned for human consumption in the European Union.