Canadian McDonald's patrons will reportedly soon see something unexpected on the menu at the struggling fast-food giant: Kale.

The world's biggest burger chain, in a battle to reinvent itself, is introducing three salads in Canada with trendy kale as an ingredient. It's also testing two breakfast bowls in southern California, one of which features kale.

The test comes as McDonald's Corp. works to shake its junk food image, with sales at established U.S. locations declining for six straight quarters. CEO Steve Easterbrook, who stepped into the top spot March 1, has said he want to turn the chain into a "modern, progressive burger company."

3 salad options

Lisa McComb, a McDonald's representative, said in an email that kale is included in a turkey sausage and egg white bowl, which also has spinach and bruschetta, in its southern California test items.

Mark Kalinowski, an analyst at Janney Capital Markets, said in a report on Wednesday, citing industry sources, that kale will make an appearance in a trio of salads at Canadian McDonald's restaurants — Caesar, Greek and harvest garden.

The embrace of kale may seem odd to some, considering McDonald's recently ran an ad that celebrated the Big Mac and mocked trendy ingredients like soy, quinoa, Greek yogurt — and kale.