The chemical properties of the high quality cassava-tigernut composite flour, as well as the physical and quantitative descriptive sensory properties of the extruded snack therefrom, were investigated. Extruded snacks were procesed from different blends of high quality cassava flour (HQCF) and tigernut composite flour at the ratio of 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70 and 20:80, 100% HQCF and 100% tigernut flour. The extrudates were produced using a single screw laboratory extruder at constant feed moisture (27%), screw speed (60 rpm) and barrel temperature (80 • C). Addition of tigernut flour improved some chemical and physical qualities of the extrudates and the study concluded that an acceptable extruded snacks can be produced from high quality cassava-tigernut flour blends.

This study investigated the mineral and antinutrient composition of extruded snack produced from different blends of high quality cassava and tigernut flour. The extruded snacks were produced using a single-screw laboratory extruder at constant feed moisture (27%), screw speed (60 rpm) and barrel temperature (80C). It was observed that the extrudates had higher values for mineral composition (phosphorus, calcium, magnesium, potassium and iron) than the composite flour which showed that extrusion cooking improves the absorption of the minerals. The antinutrient (tannin, phytate, saponin, oxalate, alkaloids and total phenolic) contents of all the flour blends significantly (P < 0.05) increased with tigernut flour inclusion. Extrusion cooking resulted in significant (P < 0.05) reduction in the antinutrients of the extrudates. The study showed that extrusion cooking reduced the antinutritional factors thereby increasing the bioavailabilty of minerals. Also, the minerals were not affected by the extrusion cooking process probably because minerals are heat stable. PRACTICAL APPLICATIONSFindings from this study have potentials to increase the productivity and value addition to tigernut, an underutilized plant specie. The snack produced is also a good alternative gluten free product.