Abstract: African breadfruit (Treculia africana Decne) was substituted with 5% fullfat corn and a range of 10-55% defatted soybean and extruded in a single screw Brabender extruder at process variable combinations determined in a 2nd order central composite design. Feed moisture and extruder screw speed were varied from 15-27% and 100-180 rpm, respectively. The design generated a total of 25 experiments from which low and high African breadfruit substitutions with corn and defatted soybean were selected and analyzed for compositional and organoleptic properties at minimum and maximum process variable combinations. Unit operations depending on the characteristic nature of seed type and extrusion process were carefully documented. Low or high substitution with 5% fullfat corn and either 10 or 55% defatted soybean, significantly (p 0.05) increased protein or decreased carbohydrate by minimum of 22.21 and 3.96%, respectively. While Na, P, Mg and Fe decreased, K, Ca and Zn increased with substitutions in raw samples. Increase in Na and Zn at maximum process condition irrespective of sample extruded was significant (p 0.05). Phytic acid, TIA and tannin contents, respectively decreased by 22.31, 83.50 and 90.06% for the control and 45.88, 91.47 and 92.55% for the high substitution at minimum process combination, while at maximum process conditions, a reduction by 27.70, 89.20 and 89.20% in phytic acid, TIA and tannin contents, respectively were recorded for the control. Panelists accepted the substituted products in all the attributes investigated better than the control. This was more significant (p = 0.05) in low substitution at minimum process variable conditions.
T.U. Nwabueze , M.O. Iwe and E.N.T. Akobundu , 2007. Unit Operations and Analyses for African Breadfruit Based Spaghetti-Type Products at Extreme Process Combinations. Journal of Food Technology, 5: 87-94.