Antioxidant Activity of Aqueous Solutions of Corn Extrudates with the Addition of Oat Flakes

Abstract

The paper presents the results of research on the antioxidant activity of corn extrudates with the addition of oat flakes. The addition of oat flakes to corn increases their nutritional value. However, the process of extrusion decreases the antioxidant content of these products. These losses are compensated by non-enzymatic browning compounds formed during the extrusion process. The objective of this study was therefore to analyze the antioxidant properties of extrudates as a function of the content of Maillard reaction products. The reference
point for determining the degree of non-enzymatic browning of the extrudate was the effect on a model reaction of lysine with glucose. The material for the test samples was made from the extruded, ground corn grain with the addition of 0, 50, 100 and 150 g kg−1 of crushed oat flakes. The antioxidant properties were investigated using the free radical DPPH• (2.2-diphenyl-1-picryl-hydrazil). RESULTS: Corn extrudate produced without the addition of oat flakes was characterized by higher antioxidant activity, but the differences with other test samples were not statistically significant. CONCLUSIONS: The results of this study show that the antioxidant capacity could be the result of the formation of colored Maillard reaction products and/or pre-melanoidins, determined by absorption at wavelengths of 320 and 420 nm.