Bob's Red Mill products labeled Gluten Free are batch tested in our quality control laboratory. We use an ELISA Gluten Assay test to determine if a product is gluten free. Our Baking Soda is made from the deposits of mineralized sodium bicarbonate. It is extracted by an all-natural water process that uses no chemicals. When used in combination with acidic ingredients, such as buttermilk or, molasses, it releases carbon dioxide that causes the batter or dough to rise. It's also a great household cleanser and odor absorber. Gluten Free, All-Natural, Kosher.