Amino acid profiles and in vitro antioxidant properties of cereal-legume flour blends

Abstract

Legumes and cereals stand a great chance as remedies to overcome incidences of protein malnutrition and oxidative stress. Cereal grains such as wheat (WT), millet (ML), maize (MZ) and acha (AC) were blended with cowpea (CP), peanut (PN) and soybean (SO) at varying levels to produce four different blends. Protein contents of the cereal-legume blends were determined and found to be higher as the inclusion level of legumes increased in the blends. Amino acid profiles and antioxidant properties of the flour blends were evaluated. Results showed that leucine was the most abundant (6.52-8.45 g/100 g) essential amino acid in the flour blends while total content of essential amino acids increased as the level of legume incorporation increased in the WT/SO (31.3-36.2 g/100 g) and MZ/CP (34.5-37.4 g/100 g). The antioxidant properties showed that MZ50:CP50 exhibited greater ferric reducing antioxidant power while WT70:SO30 and AC50:SO50 had stronger metal chelation activity and ML50:PN50 scavenged the most DPPH radicals when compared to the other flour blends. The results suggest that the composite flours have the potential to be used as ingredients for the formulation of food products with high levels of essential nutrients in addition to antioxidant benefits.