Also known as tapioca starch. You can see our quality! Tapioca flour, also known as tapioca starch, is ground to a powdery fine granulation from the dried roots of the cassava plant. It is a starchy and slightly sweet flour that is especially good for thickening soups, sauces, dips, pie fillings and puddings. Tapioca flour is also an excellent ingredient for gluten-free baking, as it lends a springy texture, promotes browning and makes crispy crusts. 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. Wholesome. Gluten free. An employee-owned company. To your good health. - Bob Moore. Dear Friends, Since starting this company over thirty years ago, our mission has always been to offer the most diverse array of stone ground, whole grain products. About ten years ago, we noticed that some folks were exclusively buying gluten free grains like brown rice, sorghum and quinoa. Soon after that, we learned all about celiac disease and gluten intolerance and how serious they are to millions of people like you. Over the years we have introduced a variety of measures to ensure purity in our line of gluten free products that have become industry standard. We inspect all farm deliveries, use dedicated gluten free production facilities and employ batch testing in our quality control laboratory. Knowing that we're providing safe and delicious gluten free foods that you and your family can trust makes it all worth the effort. To learn more about our gluten free products visit www.bobsredmill.com/gluten-free.