Amalgams

http://www.nytimes.com/2009/10/04/health/04meat.html?_r=1

Unwritten agreements between some companies appear to stand in the way of ingredient testing. Many big slaughterhouses will sell only to grinders who agree not to test their shipments for E. coli, according to officials at two large grinding companies. Slaughterhouses fear that one grinder’s discovery of E. coli will set off a recall of ingredients they sold to others.
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Cargill, whose $116.6 billion in revenues last year made it the country’s largest private company, declined requests to interview company officials or visit its facilities. “Cargill is not in a position to answer your specific questions, other than to state that we are committed to continuous improvement in the area of food safety,” the company said, citing continuing litigation.

The meat industry treats much of its practices and the ingredients in ground beef as trade secrets. While the Department of Agriculture has inspectors posted in plants and has access to production records, it also guards those secrets. Federal records released by the department through the Freedom of Information Act blacked out details of grinding operations that could be learned only through copies of the documents obtained from other sources. Those documents illustrate the restrained approach to enforcement by a department whose missions include ensuring meat safety and promoting agriculture markets.