NEW YORK - Coming soon to McDonald's: Fresh beef.

The fast food giant says it will swap frozen beef patties for fresh ones in its Quarter Pounder burgers by sometime next year at most of its U.S. locations. Employees will cook up the never-frozen beef on a grill when ordered.

It's a major shift for the world's largest hamburger chain, which has been trying to update its image as more people shun processed foods. It has been tinkering with its recipes, removing artificial preservatives from its Chicken McNuggets and cutting high fructose corn syrup from its bread.

McDonald's Corp. had been testing fresh beef at more than 400 restaurants in Dallas and Tulsa, Oklahoma, for about a year. The company, based in Oak Brook, Illinois, has about 14,000 locations in the U.S.