ABSTRACT
The effect of watermelon rind powder addition on the functional, pasting and microbiological quality of Sorghum based mumu was evaluated. Sorghum-based mumu was prepared from composite flours of 85:15, 75:15, 70:15 and 65:15% roasted sorghum flour and roasted partially defatted groundnut flour respectively and included with 0, 10, 15 and 20% watermelon rind powder respectively which were known as sample A, B, C and D accordingly. Subsequently, the functional, pasting properties and microbial quality was assessed. Functional properties values; Bulk density (0.89 to 0.80mg/100g), reconstitution index (4.99 to 4.89) and swelling index (2.35 to 2.20) decreased significantly (p < 0.05) with increase in watermelon powder addition while water absorption (10.36 to 10.97g/g), oil absorption (10.33 to 10.79) and foam capacities (12.46 to 13.85%) increased with increase in watermelon rind powder. The pasting properties; peak (302.22 to 292.44 RVU), trough (156.44 to 150.00 RVU) and Final viscosities (412.69 to 400.76RVU), and breakdown (149.95 to 140.59RVU) decreased significantly (p < 0.05) with increased in watermelon rind powder while setback viscosity (101.05 to 115.59RVU), pasting temperature (59.32 to 62.02oC) and pasting time (4.93 to 5.13mins) increased. Microbial analysis revealed the following ranges: Total viable count, 0.5x102 to1.0x102 cfu/g, fungi count of 6.1x101- 9.9x101 cfu/g and no coliform was detected. Overall, addition of watermelon rind powder showed good functional, pasting and microbiological qualities of sorghum based mumu.