Patent ID: 7618671

Claim:
A method for selectively recovering isoflavones and removing the oligosaccharides raffinose and stachyose from an aqueous mixture comprising said isoflavones, said oligosaccharides raffinose and stachyose, and digestible sugars, the method comprising the steps of: (a) contacting a beta zeolite with the aqueous mixture, whereby at least a portion of said isoflavones are adsorbed onto the beta zeolite to form adsorbed isoflavones; (b) separating the beta zeolite from the aqueous mixture resulting from step (a); (c) contacting the beta zeolite separated in step (b) with an organic solvent to release the adsorbed isoflavones; (d) contacting the aqueous mixture remaining after step (b) with an ultrastabilized, hydrophobic zeolite Y having a Si/Al ratio of about 10 to about 45, whereby at least a portion of said oligosaccharides raffinose and stachyose bind to said ultrastabilized hydrophobic zeolite Y and is selectively removed from the aqueous mixture, thereby forming an aqueous mixture having an increased proportion of the digestible sugars relative to the oligosaccharides; (e) separating the ultrastabilized, hydrophobic zeolite Y from the aqueous mixture resulting from step (d); and (f) recovering the aqueous mixture remaining after step (e).