Cherry pies are the only frozen fruit pies that must meet quality standards set by the Food and Drug Administration. Other fruit pies — including apples, blueberries and peaches — are exempt.

The FDA created the rule more than 30 years ago. At least 25% of the pie by weight must contain cherries, and no more than 15% of the cherries can be blemished. No one recalls why cherries were singled out. "We likely issued the one standard because we were petitioned to," FDA spokesman Michael Herndon says.