Fast-food giant McDonald's, which has relied on frozen beef patties since the 1970s, said it's launching Quarter Pounders made with fresh beef in about 3,500 restaurants starting Tuesday.

  • Test in Texas, Oklahoma restaurants was well received
  • McDonald's hopes to have in 14,000 U.S. locations by early May
  • Company trying to improve image as people shun processed foods

The fresh beef is available at about 3,500 domestic restaurants so far and it plans to reach some 14,000 U.S. locations by early May.

Locations in Hawaii and Alaska are not included in the rollout.

McDonald's says workers will cook up the fresh beef on a grill when the Quarter Pounder and "Signature Crafted" burgers are ordered.

After the test of fresh beef in more than 400 restaurants in Texas and Oklahoma, the company said it received a 90 percent satisfaction rating from customers as well as a 90 percent intent to repurchase rate.

The change is the latest by the Oak Brook, Illinois-based company to improve its image as more people shun processed foods.