What Does a Quarter Pounder and a Bottle of Cleaning Product Have in Common?

Answer: They both contain ammonia...

From healthiertalk.com comes this excerpt from an article.

...But before even going to the contamination issue, which the press went all agog about, what about the presence of ammonia in beef? How did the USDA come to approve treating food with a substance that’s corrosive to the skin, eyes, and lungs — that literally can eat a hole through the gut?

Processed Meat & Fat "Paste"

It seems that back in 2000 or so, the executives at Beef Products Inc. felt frustrated that they couldn’t use the fatty waste in the beef for anything except pet food and cooking oil, since fat is so vulnerable to bacterial contamination and wouldn’t pass inspection. But then, someone at the company had a money-making brainstorm — if the fatty matter could be treated with large-amounts of ammonia, perhaps the contaminants would die and then the waste could be ground into a paste, added to hamburg, and sold for a far higher price. And sure enough, tests showed that the ammonia did seem to kill off E. coli and salmonella, and the company started marketing its ammonia-treated products far and wide. The FDA and USDA approved, and in fact, granted an exemption to Beef Products, Inc. so that the ammonia-infused ground beef coming out of that company didn’t have to go through regular inspections. Now, ammonia-treated beef ends up in 70 percent of all hamburger sold in the US, including meat sold at Burger King, McDonald's, through the school lunch program, and in numerous supermarket chains...