Physicochemical Properties of Flour Blends and Chemical Composition of Cookies from Selected Underutilized African Crops

Abstract

Cookies are one of the most consumed snack foods globally. Cookie manufacture had conventionally been of wheat flour, more probably than not being imported. Scientists in Africa have focused on reducing general dependence on wheat flour for the manufacture of foods with some degree of success. Sweet potatoes (SP) have gained attention from scientists, and cowpea leaves are gradually gaining attention because they possess abundant nutrients and bioactive compounds. Moringa oleifera leaves are also rich in vitamins, minerals, and bioactive compounds, and the combination of these components could help in the prevention of diabetes and other degenerative diseases such as cancer. This paper focused on the production of cookies baked with non-wheat flour. The blends of flour were prepared from the flours of cowpea, sweet potato, and moringa leaves in the following ratios: 80:17:3, 87:10:3, 80:3:17, and 87:3:10, respectively. Physicochemical properties were determined. The flour blends were used to prepare the cookies, and the proximate composition of the cookies was also determined. Physico-chemical properties results showed that the bulk density of the flour blends was extremely low (0.55 to 0.60 g/ml), whereas their water absorption capacity and swelling index were extremely high (240 to 281% and 1.24 to 1.57 ml/g, respectively). The moisture content was also very low (between 5.84 and 7.23%), appreciably high ash (between 11.91 and 14.59%), fibre (between 6.08 and 14.31%), and protein contents (between 11.11 and 12.95%). The proximate composition of the cookies ranged from 4.55 to 9.60% for moisture, 8.51 to 10.79% for ash, 3.26 to 4.02% for fibre, and 10.85 to 14.35% for protein, respectively. The cookie sample with the highest proportion of moringa leaf replacement had the highest amount of protein and fibre content. Overall, nutritionally dense cookies were produced from composite sweet potato, cowpea, and moringa leaves flours with no supplementation with wheat.