December saw the scrutiny on Chipotle Mexican Grill intensify as the under-pressure US fast-casual chain battled to restore its reputation after a series of food safety scares. Chipotle's success has been built on its ingredient claims and the initiatives on sourcing continued throughout the industry with a series of announcements. Meanwhile, two US fast-food giants, Yum! Brands and Burger King, outlined its ambitions in emerging markets.