Gluten-free flours are expensive, and if you like to cook and bake from scratch, you’ll want to pay close attention to protecting the shelf life of your flours as long as you can. Always keep flour away from direct sunlight or moist air. Storing flours in dark, dry places fancy, clear glass canisters on the counter where light can penetrate them.
Upon opening, it’s best to refrigerate certain gluten-free flours to protect taste and texture as well as extend their life. Those that have high fat content are prone to rancidity and should always be refrigerated. These include flours such as nut flours, flaxseed flour, amaranth flour, brown rice flour, and millet. If you live in a warm and humid climate, refrigerating your flours is recommended regardless of flour type. However, always refer to the directions on the package.
Whether stored in the refrigerator, freezer, or cabinet, make sure your gluten-free flours are well protected from air; simply rolling down the package and clipping it with a clothespin is not going to produce an airtight environment. Consider transferring them to plastic containers with lids or durable plastic bags, like heavy-duty freezer bags. But if you choose to use the packages that the flours come in, at the very least, double protect them by placing them inside food-quality, plastic storage bags and sealing them tightly. These storage tips are also applicable for your gluten-free grains such as teff, quinoa, and amaranth.