"Pink slime" (a dysphemism for lean finely textured beef or LFTB, finely textured beef, and boneless lean beef trimmings or BLBT) is a meat-based 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 product 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.