ANTIOXIDANT ACTIVITY OF SOYBEAN FLOUR AND DERIVATIVES–A REVIEW

ABSTRACT Soybean flour and various derivatives, with different natural, interacting primary antioxidants and synergists can stabilize lipids in formulated foods. Soybean flour has been shown to be a basic source of such antioxidant compounds as isoflavone glycosides and their derivatives, phospholipids, tocopherols, amino acids and peptides. There may be some antioxidant impact from aromatic amines and sulfhydryl compounds. Successful efforts have been made to concentrate the antioxidant activity in soy flour by aqueous extraction and by extraction with various organic solvents. Residual antioxidant activity has been reported in food systems containing soy protein concentrates, isolates and textured vegetable protein. Soy protein hydrolyzates have antioxidant activity which is associated with free amino acids and lower molecular weight peptides.