Simple and efficient procedure for removing the 34 kDa allergenic soybean protein, Gly m I, from defatted soy milk

The 34 kDa protein in the salted-out fraction of soy milk is shown to be identical to the allergenic soybean protein, Gly m I, by N-terminal amino acid sequencing and immunoblotting, using the monoclonal antibody against Gly m I. Treatment of soy milk with 1 M Na2SO4, acidifying to pH 4.5 and centrifugation removed more than 90% of the 34 kDa protein with an overall yield of 70% of total soy protein.