( NewsNation) — Frozen waffles sold at major retailers across the U.S. and Canada have been recalled after possible listeria contamination. Illinois-based TreeHouse Foods, LLC voluntarily issued the recall Friday after doing routine testing at one of its 26 manufacturing facilities.

TreeHouse Foods, Inc., said Friday that it issued a voluntary recall after discovering possible contamination during routing testing at its plant.

A massive recall affecting more than 500 varieties of frozen waffles has been issued by the company that manufactures them, according to a press release.