It used to be thought that Americans had the safest food supply in the world. But in recent years, recalls for everything from peanut butter to pot pies have some consumers wondering how these contaminated products keep slipping through the cracks.

There are many critics of the U.S. food supply system. The Organic Consumer Association argues that the way animals are raised is part of the problem, and points out that the European Union doesn't buy most U.S. beef products because the cattle are treated with growth hormones.

Some politicians also think the U.S. food inspection system needs improvements. Representative Bruce Braley (D-Iowa) and Senator Tom Harkin (D-Iowa) have proposed the Fresh Produce Safety Act, which would boost safety procedures and standards. The bill would give the FDA authority to make its voluntary guidelines mandatory, and would require stepped-up inspections of operations that grow and process fresh produce.