soybean curd
2.The Protein in residual water from soybean curd prodution was concentrated by ultrflltration membrane process with several membranes of different materials and cut-off molecular weignt, among which PAN (of polyacrylo-nitrile) and CXA-1 (of cellulose acetate) membranes showed high retention of 90-95% and flux of about 40-80 l/m2h.

