Effect of period of maize fermentation and souring on chemical properties and amylograph pasting viscosity of ogi

Abstract

Changes in the pH of the steeping and souring water, titratable acidity, starch, damaged starch, diastatic activity and liquefaction number of ogi, during fermentation of maize, as well as the souring of ogi slurry and maize flour, were investigated. The practice of wet-milling significantly reduced damaged starch levels, whereas starch content decreased as fermentation or souring proceeded. Starch content and Amylo-graph peak viscosity were higher for wet-milled ogi (75–89% w/w and 1030–1250 Brabender units) than dry-milled ogi (53–61% w/w and 740–960 Brabender units). Stability, index of gelatinisation and Adams Consistometer values decreased with either fermentation or souring time. The implications of these parameters for ogi quality are discussed.