There is no evidence that the white powder found on sticks of gum is wheat flour or that flour is dusted on machinery used to make gum.
Wrigley said it could find no evidence that wheat is used in the production of gum. The white powder on their products is granulated sugar, or a sugar substitute in the sugar free version. The director of protein research and development at Texas A&M said companies overall use cornstarch combined with a sweetener to dust sticks of gum. The powder on the gum absorbs moisture in the air and keeps the gum from getting sticky.
Wrigley has tested its gums and they do not contain gluten. Dubble Bubble, which is made by Tootsie Roll, is gluten free. The company specifically says it does not use gluten in any of its products, including the dusting of conveyor belts.