Burger King Seeks to Lower Its Cows' Methane Emissions According to CNN Business, the chain will add 100 grams of lemongrass to the farm animals' diet. Restaurant Brands International, which owns Burger King, has confirmed the move. Burger King says the addition of lemongrass to the cows' diet will slash methane emissions, which contribute to climate change, by 33 percent daily. RBI Global CMO Fernando Machado The signature Whopper with lemongrass-fed beef will be available in select Burger King locations nationwide. The chain says these areas include Los Angeles, New York, Miami, Austin and Portland. According to CNN Business, Burger King is also looking to remove artificial ingredients from its products by the end of 2020.