Nutritional, physicochemical, and sensory characteristics of extruded Bambara groundnut ( Vigna subterranea )‐based ready‐to‐eat breakfast cereal

Abstract

Bambara groundnut, malted sorghum, pearl millet, and banana were processed into flours and mixed in the ratio of 50:20:20:10, respectively. Using response surface methodology, screw speed (300–350 rpm), barrel temperature (180°C–220°C), and feed moisture (12%–16%) were varied and their effects on the chemical, physicochemical, sensory, and microbial characteristics of Bambara groundnut-based ready-to-eat breakfast cereal were investigated. The flour blend showed a significant increase in protein (20.00%) as compared to using cereal grains alone. Improved expansion ratio (7.27), protein solubility (0.36%), and in vitro starch digestibility (157.35 µg/g) were achieved. Also, overall acceptability of 8.40 for the sweetened sample as well as microbial stable product were established. Bambara groundnut as a base ingredient for food extrusion can be used to produce a more nutritious, less expensive, and an overall acceptable breakfast cereal. Practical applications Breakfast cereals are very handy, especially for urban-based individuals due to tight working schedule resulting to insufficient time for cooking detailed foods. Therefore, the need to remodel the existing starch-based ready-to-eat breakfast cereals to more nutritious protein-based products using affordable local crops is paramount. The use of extrusion cooking would enhance palatability, production yield to meet the daily increasing population, and reduce high postharvest losses due to underutilization of these crops. In summary, the outcome of this study would provide information for the possibility of scaling up production of protein-based ready-to-eat breakfast cereals using available cheap crops and increasing the prevalence of healthy convenience food products in the market.