KSDK-TV

Treating scrap meat with ammonium hydroxide creates a pink goo that is used to extend meat products like chicken and beef and to kill bacteria.

McDonald's confirmed that it has eliminated the use of ammonium hydroxide — an ingredient in fertilizers, household cleaners and some roll-your-own explosives —  in its hamburger meat.

The company denied that its decision was influenced by a months-long campaign by celebrity chef Jamie Oliver to get ammonium-hydroxide-treated meats like chicken and beef out of the U.S. food supply. But it acknowledged this week that it had stopped using the unappetizing pink goo — made from treating otherwise inedible scrap meat with the chemical — several months ago.

Besides being used as a household cleaner and in fertilizers, the compound releases flammable vapors, and with the addition of certain acids, it can be turned into ammonium nitrate, a common component in homemade bombs. It's also widely used in the food industry as an anti-microbial agent in meats and as a leavener in bread and cake products. It's regulated by the U.S. Agriculture Department, which classifies it as "generally recognized as safe."

McDonald's decision was first reported this week by the Daily Mail, a blaring British tabloid, which trumpeted it as a victory for fellow Brit Oliver against the monolithic U.S. food industry. 

Oliver's campaign began in April, when he included a segment on what he called "pink slime" on his TV show, "Jamie Oliver's Food Revolution" (warning: some readers may find this video distasteful):

The use of treated scrap meat "to me as a chef and a food lover is shocking," Oliver said. "... Basically we're taking a product that would be sold in the cheapest form for dogs and making it 'fit' for humans."

Todd Bacon, McDonald's senior supply chain officer, told the Daily Mail that the decision "was not related to any particular event, but rather to support our effort to align our global beef raw material standards." 

In a statement, McDonald's clarified that it stopped using "select lean beef trimmings" — its preferred term for scrap meat soaked in ammonium hydroxide and ground into a pink meatlike paste — at the beginning of last year.

"This product has been out of our supply chain since August of last year," it said.

Sarah Prochaska, a registered dietitian at Barnes-Jewish Hospital in St. Louis, said that ammonium hydroxide is widely used in the U.S. food industry but that consumers may not be able to know what products include it because the USDA considers it a component in a production procedure — separating scrap meat — and not an ingredient that must be listed on food labels.

"It's a process, from what I understand, called 'mechanically separated meat' or 'meat product,'" Prochaska told NBC station KSDK of St. Louis.

While the government considers it safe, it certainly "does not look anything like ground beef," she said. And since it's not on nutrition labels, the only way to avoid it "would be to choose fresher products, cook your meat at home, cook more meals at home," she said.

NBC station KSDK of St. Louis contributed to this report.

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