High-protein flours are ground from legumes of all sorts; garbanzo, fava, and soy are among the most common, with soy flour being available in many supermarkets. In all cases, they are useful in baking because their high protein content is the closest approximation to gluten found in gluten-free flours. However, all high-protein flours on the market at this time are strongly flavored. Most wheat-free bread recipes that use these flours will combine them with a lower-protein flour for a more neutral taste.
High-protein flours are not the best choice for replacing flour in recipes that don't depend on gluten, and their flavors are too noticeable for them to make great sauces or gravies. They are acceptable for dredging meats, however, especially if they will be used in a dish that has other strong, complementary flavors.
Celiacs are unable to use barley and rye for baking, but many people with wheat allergies tolerate these grains. Both of these flours contain some gluten, but they are lower in gluten than wheat and so are not one-to-one replacements for wheat in baking. Rye flour has a strong flavor and is used to make dense pumpernickel breads. Barley is the more versatile of the two from a culinary standpoint, but has higher cross-contamination risks for people with wheat allergies.
Other Wheat-Free Baking Resources
You'll find a few ingredients in many wheat-free baking recipes that you might not be familiar with. Gums are used in combination with flour mixes in baking as a substitute for gluten. The two you are most likely to find in recipes are xanthan gum, which is derived from sugar (often from corn), and guar gum, which is derived from a type of bean. Purchase these in many health food stores or online.
Many ingredients are used to add protein to baked goods that are made primarily from lower-protein flours. Some -- like milk, eggs, soymilk, and other nondairy milk alternatives -- are grocery store staples. Others are a bit more obscure:
- Egg replacer is used not just to replace eggs, but also to leaven and add protein to wheat-free baked goods. It's available at many health food stores or at some supermarkets.
- Nut meals are dense and rich in protein. They are obviously not suitable for people with tree nut allergies. Find them at health food stores or online.
- Powdered dry milk is available in bags in most supermarkets, usually in the baking section near canned condensed milk.