Burger King announces move to be preservative-free with moldy Whopper ad

Burger King announced Wednesday the company is removing preservatives from its Whoppers. To prove it, the fast-food giant is running an ad campaign that shows what its signature sandwich looks like more 30 days after being cooked: moldy and disgusting.

In "The Moldy Whopper" ad, Burger King displays the decay of the burger over 34 days in a time lapse. By the end, the sandwich is a vivid shade of green-blue.

"the beauty of real food is that it gets ugly. that’s why we are rolling out a WHOPPER® that is free from artificial preservatives. isn’t it beautiful," the company wrote on Twitter.

"We believe that real food tastes better," Fernando Machado, chief marketing officer of Restaurant Brands International Global, which owns Burger King, said in a press release. "That’s why we are working hard to remove preservatives, colors and flavors from artificial sources from the food we serve in all countries around the world."

The statement said that the moldy burger ad reveals "the beauty of no artificial preservatives" and that Whoppers will be preservative-free by the end of the year. This more natural version of the burger is already available in 400 locations throughout the U.S.