Production of Shelf-Stable Fermented Maize Starch Flour for Akpan: Effects of Fermentation and Drying Conditions on Flour Characteristics and Final Product Quality.

Akpan is a Beninese yogurt-like product whose quality and usability depend on fermented maize starch (FMS), a traditionally produced substrate characterized by inconsistent quality and limited shelf life. This study aimed to optimize the fermentation and drying conditions of maize starch to produce a stable FMS flour capable of yielding akpan with properties comparable to commercial akpan. A Box-Behnken response surface design was used to assess the effects of fermentation duration (24-72 h), drying temperature (45°C-65°C), and drying duration (4-6 h) on physicochemical and pasting characteristics of the flour, as well as the textural properties of akpan. Two commercial akpan samples were analyzed as benchmarks. Fermentation duration primarily influenced viscosity, while drying temperature significantly affected starch retrogradation and syneresis. Titratable acidity increased with both fermentation duration and drying temperature, while pH and lactic acid content remained relatively stable. Optimal conditions (60-72 h fermentation and ~55°C drying) produced FMS flour yielding akpan with titratable acidity (0.25-0.34 g/100 g), firmness (~14 g), and syneresis (< 18%), comparable to commercial products. Notably, pasting properties of FMS flour did not predict akpan viscosity, highlighting the importance of partial cooking conditions. These findings provide a basis for standardizing akpan production and improving its scalability and market potential.