Pure Gluten Free Brown Rice Flour 500g Rice flour is made from finely-milled rice & is used as a partial substitute for wheat flour in gluten-free baking, as well as being an effective thickening agent in cooking. Brown rice flour is made from uncooked brown rice, which is also referred to as wholegrain rice. The rice retains its bran layer which means that it also retains its oil, fibre & magnesium content.