Antioxidative, nutritional and sensory properties of muffins with buckwheat flakes and amaranth flour blend partially substituting for wheat flour

Effects of partial replacement (17-50%) of wheat flour (WF) with buckwheat flakes/amaranth flour blend (B-A) on quality attributes of muffins during storage, with special attention on their antioxidative, nutritional and sensory properties, were studied. Increasing the B-A content in muffins resulted in progressing antioxidative activity, e.g. 1,1-diphenyl-2-picrylhydrazyl scavenging by 26-51%, as well as in increased mono- and polyunsaturated fatty acid (FA) contents; e.g., linolenic acid content was 0.34 g/100 g FA in control (C-muffins), and 0.53 g/100 g FA in the muffins with the highest WF substitution. Moreover, fibre content in that latter case was 2.5-fold higher than in C-muffins. The content of secondary lipid oxidation products did not exceed the upper safety limits in muffins with higher WF substitution of by B-A. Intensities of cereal, nut aroma and taste increased with increasing B-A content, but that of buttery aroma decreased. Intensities of off-aroma and of bitter taste were low in fresh muffins but increased with storage due to increased secondary lipid oxidation products. Higher WF replacement by B-A (33 or 50%) in muffins improved their nutritional and antioxidative properties, effectively inhibiting hydroperoxide decomposition, thus preventing generation of toxic secondary lipid oxidation products.