Characterization and functional properties of rice bran proteins modified by commercial exoproteases and endoproteases

Large portions of rice bran protein cannot be solubilized by mild solvents, but endoprotease use increases protein recovery. Bran was treated with 2 commercial proteases to achieve 8% to 9% peptide bond hydrolysis. The exo- plus endprotease was preferred to just using endopeptidases as it allowed the production of protein hydrolysates with enhanced functional properties. Solubility and emulsification activity and stability of hydrolysates produced with the protease blends were greater than that produced with endoprotease alone. These high value hydrolysates, produced from rice bran, an underutilized rice milling coproduct, are suitable for many processed foods, particularly those requiring potent solubility and emulsification at mildly acidic conditions.