Storage stability of dehydrated and soy-fortified fermented maize meal

Abstract

Dehydrated fermented maize meal samples fortified with soy flour at 0, 10, and 20% replacement concentrations were stored at 25, 35, 45 and 60°C. Selected samples were analyzed for nonenzymatic browning, lipid oxidation, available lysine loss, and change in pasting properties during storage. Production of browning pigments followed zero order kinetics with activation energies of 125-150 KJ/mole. Multi-phase loss of available lysine was observed in soy fortified maize meal but not in unfortified samples. Total carbonyl content of the samples increased during storage. Considerable changes in pasting properties of the samples occurred during the first 2 months of storage at 25 and 35°C. Nineteen weeks of storage at 35°C caused adverse changes in sensory quality of the 10% soy fortified sample, but not in the unfortified sample