Product characteristics of soya protein concentrates and isolates can be varied by using various processing treatments. These treatments can involve the use of enzymes, solvents, heat and pH adjustment, or combinations of these treatments to produce concentrates and isolates with the desired functional properties, such as water absorption, gelation, whipping ability, fat and oil emulsification, binding and varying degrees of protein solubility. The defatted soya flakes customarily used for the manufacture of concentrates and isolates are not segregated on the basis of variety. However, regional differences exist in the extractable protein content of the defatted flakes. Processing controls are essential in producing consistent quality and functional soya protein concentrates and isolates. Production parameters such as solvent treatment, desolventizing, enzyme treatment, heat, or pH adjustment of the soy flakes during processing must be stringently controlled to prevent variation in finished product characteristics and functionality.