Abstract: A high quality soy protein concentrate (SPC) was produced by a process of enzyme treatment combined with ultrafiltration. Soy flour, the starting material, was enzymatically treated with commercial pectinases and diafiltered with a porous stainless steel ultrafiltration system. The resulting product had reduced levels of physic acid and nucleic acids due to contaminant phytase and nuclease activity in the pectinase enzymes. The functionality of the SPC was improved due to increased solubility compared to conventional soy isolates produced by acid precipitation. High performance liquid chromatography gel filtration profiles indicated that the proteins in the SPC remained intact. The SPC also had reduced flavor when compared to the original soy flour according to gas chromatography flavor profiles and sensory evaluation.