""Pink slime" is a dysphemism for a meat-based product the meat industry calls "lean finely textured beef" (LFTB),"finely textured beef", and "boneless lean beef trimmings" (BLBT). It was also derided as "soylent pink".
In 2001, the United States Department of Agriculture (USDA) approved the product for limited human consumption, and it has been used as a food additive to ground beef and beef-based processed meats at a ratio of usually no more than 25 percent of any product. 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 March 2012, an ABC News series about "pink slime" included claims that approximately 70 percent of ground beef sold in U.S. supermarkets contained the additive at that time, after which some companies and organizations stopped offering ground beef with the product. "Pink slime" was claimed by some originally to have been used as pet food and cooking oil and later approved for public consumption, but this was disputed in April 2012, by both the Food and Drug Administration (FDA) administrator responsible for approving the product and Beef Products, Inc. (BPI), the largest U.S. producer. In September 2012 BPI filed a lawsuit against American Broadcasting Company for false claims"
"Producers of LFTB start with beef trim. This is the “waste” meat and fat that results from trimming higher quality beef cuts (such as steaks) to customer specifications, and is usually used to make ground beef.
The LFTB process begins by separating most of the fat from the beef. This is done by warming the trim and “spinning out” the fat in centrifuges. The result is a very lean beef: approximately 94-97% lean, according to Beef Products Inc. This lean beef can be mixed with higher-fat beef in order to produce low-fat ground beef and processed meat products.
But beef trim is notorious for carrying pathogenic bacteria – especially, E. coli O157:H7 and its close cousins, the non-O157 STEC bacteria. So Beef Products Inc. developed an ammonia gas treatment step to kill the microbes."
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