Abstract: The soybean whey ultrafiltrating was studied on extracting the soybean oligosaccharides. It was found that under different conditions of membrane, cutmolecular weight, pressure and temperature, the ultrafiltration velocities were different along with time. In the permitted range of the module, the higher press ure and temperature showed advantages for the ultrafiltration.XHP03 was chosen as the best ultrafiltration membrane under excellent conditions.

Key words: Soybean whey Ultrafiltration Soybean oligosaccharides