The soybean (Glycine max) is a species of legume native to East Asia. Soy flour refers to defatted soybeans ground finely enough to pass through a 100-mesh or smaller screen where special care was taken during desolventizing (not toasted) in order to minimize denaturation of the protein to retain a high Protein Dispersibility Index (PDI), for uses such as extruder cooking of textured vegetable protein. Soy flour is made from roasted soybeans that have been ground into a fine powder. Rich in high-quality protein and other nutrients, soy flour also adds a pleasant texture and flavor to a variety of products. Two kinds of soy flour are available: Natural or full-fat soy flour contains the natural oils that are found in the soybean. Defatted soy flour has the oils removed during processing. Both kinds of soy flour will give a protein boost to recipes; however, defatted soy flour is even more concentrated in protein than full-fat soy flour. Like whole grain flours, both defatted and full-fat soy flour should be stored in the refrigerator or freezer.
