BIOACTIVE COMPOUNDS AND ANTIOXIDANT POTENTIAL OF SOY PRODUCTS

Abstract

The aim of this work was to evaluated the amounts of bioactive compounds in soybean and derived products and the antioxidant activity (AA) assessed by the methods of ABTS·+ , DPPH· , FRAP and peroxidation of linoleic acid (PLA). The micronized soy protein (MSP), defatted soy flour (DSF) and textured soy protein (TSP) had a higher content of phenolic compounds and higher antioxidant activity (AA), than the other products. MSP and tofus had the highest content of flavonoids and phytic acid (PA), respectively. The AA correlated with total phenolics and flavonoids, but the PA can act synergistically chelating the pro oxidants ions iron and copper. The highest concentration of copper was in soy protein isolate, and of iron in an ingredient of soy fiber and soy germ. Many compounds present in soy products contribute for the AA, but the concentration and potential will depend on final preparation of the grain or ingredients before consumption.

Keywords

• Phenolic compounds
• flavonoids
• phytic acid
• iron
• copper