Five wheat flours, three milled from high-protein hard wheats and two from low-protein soft wheats, were developed into doughs, dispersed in water, and fractionated by centrifugation for 15 min at J,500 X g at room temperature for a total of 0.5-1 hr. The fractions included a low-protein (0.6-0.8%) prime starch, one or two gluten fractions containing up to 67.0% protein (N X 5.7, dmb), tailings, insoluble fibers, and water solubles. The protein-rich fractions contained up to 5.4 times the protein contents of the original flours. Total prime starch yields were up to 70% of total dry matter recovered. Protein recoveries in the protein concentrates were up to 88%. The total water load in the fractionation process was as low as 2.0 times the flour weight. This article describes a closed system that produces a concentrate high in protein and prime starch.