My daughter, 13, has celiac disease and must eat gluten free. I'm trying to figure out how to store ingredients for making flour as opposed to pre-ground flour. We're fairly new to celiac disease, so we haven't used any bean flours yet. Many flours are made with rice flour as the main ingredient. Brown rice would be healthier but wouldn't store as long as white rice. I haven't researched making rice flour from rice, but I assume it can be done. The other usual ingredients in flours are starches - tapioca, flour, corn. Does anyone know the shelf-life of the starches?