Preparation and Evaluation of Supercritical Carbon Dioxide Defatted Soybean Flakes

Full-fat soybean flakes were extracted with supercritical carbon dioxide (SC-CO2) at pressures of 10,600–12,400 psi, temperatures from 80–100°C, and moisture levels of 5–13.5%. Conditions could be selected to produce defatted soybean meals with nitrogen solubility indices greater than 70% and flavor scores greater than 6.5 on a scale of 1 to 10 (1 = strong and 10 = bland). The usual grassy-beany and bitter flavors of hexane-defatted soybean flours were only minimally detectable in the optimally SC-CO2-extracted materials. Bland, defatted soybean meal prepared by SC-CO2 extraction was further processed into high-quality protein concentrates and isolates that were stable when stored under adverse conditions.