Derived from roasted soybeans that have been ground into a fine powder, soy flour is a rich source of protein, isoflavones, iron, and calcium. Soy flour contains almost three times the amount of protein as wheat flour, and it is also a good source of riboflavin and pantothenic acid. Soy flour may be used in a number of ways, including adding it to sauces and gravies as a thickener, or to pancake batter for a nutty flavor and protein boost. Soy flour helps to enrich pasta and breakfast cereals, and it adds moisture to baked products.
Soy flour is available in a low-fat and a full-fat form with the full-fat flour containing natural soybean oils.
It is best kept in the refrigerator or freezer to maintain freshness (it keeps for about a year).
Soy flour is gluten-free so it cannot completely replace wheat flour in a yeast dough, but you can safely replace 1/4 of the amount of wheat flour with soy flour in yeast dough, quick breads, and muffins. Stir soy flour before measuring as it tends to become densely packed in its container. To enhance its nutty, rich flavor, sprinkle the soy flour over a dry skillet and cook over moderate heat. As products that have been cooked with soy flour tend to brown quickly it may be prudent to shorten cooking time or lower temperature.