Akamu is a lactic acid bacteria fermented cereal-based food that complements infant diets in most African countries. The effect of fermentation with Lactobacillus (L.) plantarum starter culture and gamma-irradiation on the pasting and morphological properties of Akamu was investigated. The sensory property of porridges from the L. plantarum fermentation and artificially acidified maize slurries was also investigated. The irradiated ground maize (IGM) and its L. plantarum strain fermented samples had significantly (p<0.05) the lowest peak (128.70 – 135.33 RVU) and final viscosities (68.50 -108.33 RVU). Un-irradiated ground maize (GM) and the traditionally fermented samples had significantly (p<0.05) the highest pasting properties (1920.50 – 2641.00 and 3378.80 – 3819.00 RVU for peak and final viscosities respectively). Scanning electron microscopy revealed the granular structure of starch: fermented samples had etches, while irradiated granules were rough and different from its un-irradiated counterpart. Porridges of the un-irradiated ground maize and the traditionally fermented sample had thick and solid linkages against the weak and viscous nature of irradiated samples. The sensory attributes (flavour, sourness, and overall acceptability) of the porridges from L. plantarum fermented sample was significantly (p>0.05) the most acceptable to the assessors. This study revealed that irradiation lowered the pasting properties of the maize slurries and caused changes in the morphological properties of both the uncooked slurries and their porridges. The sensory attributes of Porridge from the L. plantarum fermented maize slurry were most acceptable to the assessors.

Akamu, fermentation, gamma irradiation, maize slurries and porridges, pasting properties, morphological and sensory properties