In the 1980s, a process was developed to recover all this lost meat. Trimmings are put in a giant centrifuge, heated slightly, and spun. Like a washing machine’s spin cycle that spins off water, the fat is spun off from the meat. What is left over is of a gooey pink consistency, hence the term “pink slime.” The recovered meat is then put through a thin tube and treated with ammonia gas. The gas reacts with the water in the meat to form ammonium hydroxide, reducing acidity and killing pathogens.”
In the case of pink slime, or “Lean Finely Textured Beef”, the main focus are the beef trimming along with anhydrous ammonia and the use of ammonium hydroxide.
The biggest concern for the beef trimming were foodborne illness such as E.coli or salmonella. Anhydrous Ammonia were used as an antimicrobial intervention however, anhydrous ammonia is also used to fertilize corn. When anhydrous ammonia is mixed with water, it is called ammonium hydroxide and it safer compare to concentrated anhydrous ammonia. The FDA has approved this process in 1974 after conducting researches with Life Science Research Office