The U.S. Department of Agriculture said Thursday that school districts don't have to receive meat products that contain "pink slime" beef in food provided by the government, the Wall Street Journal reported.

The decision to allow school districts to have a choice beginning in the 2012-13 school year comes after mounting public concern over the USDA's plans to buy millions of pounds of the ammonia hydroxide-treated beef trimmings for the federal school lunch program.

The USDA said "requests from school districts across the country" forced its hand.

Chellie Pingree, a Democratic congresswoman from Maine, said, "There is only one word for this product: gross. McDonald's and Burger King won't serve it in their restaurants and it doesn't belong in school cafeterias either."

She sent a letter dated March 14 to USDA Secretary Tom Vilsack asking the department not to allow what the industry and USDA calls "lean finely textured beef" into school lunches.

The USDA has been buying meat containing the beef product for the National School Lunch Program since the early 1990s, but says it is always limited to 15 percent of a single serving of ground beef. About seven million pounds, or 6.5 percent, of the roughly 112 million pounds of ground beef purchased for the current 2011-12 school year was made up of the lean finely textured beef, according to USDA data.

A petition launched by food columnist Bettina Siegel a week ago demanding the USDA not purchase the beef product has received more than 226,000 signatures as of Thursday.

It's wrong, she said in the petition, "to feed our children connective tissues and beef scraps that were, in the past, destined for use in pet food and rendering and were not considered fit for human consumption."

About 32 million children are served every school day in the federal school lunch or breakfast programs and 15 percent to 20 percent of that food comes directly from USDA procurements, according to the School Nutrition Association.

Meat-industry representatives say there is absolutely nothing unsafe about the product, which is approved and inspected by the USDA.

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