TRADITIONAL PROCESSING METHODS REDUCED PHYTATE IN CEREAL FLOUR, IMPROVED NUTRITIONAL, FUNCTIONAL AND RHEOLOGICAL PROPERTIES

Abstract

The impact of traditional processing methods on the phytate, nutritional, functional and rheological quality of flours from sorghum, maize and millet were investigated. The grains were either spontaneously fermented, malted, roasted or unprocessed before separately milled into different flours. The phytate content, proximate, functional and pasting properties of processed grains were determined using standard methods. Phytate level reduced almost three-folds with malting, two-folds with fermentation and one-fold in roasted flour samples. Malting resulted in a 36% and 54% increase in sorghum and millet’s crude protein content, respectively. The total energy for sorghum ranged from 387.00–393.00 kcal/100 g; that of maize ranged from 387.00–396.00 kcal/100 g, while millet ranged from 390.30– 409.10 kcal/100 g. Processing methods significantly (p < 0.001) reduced bulk density, increased water holding capacity and oil absorption capacity of flours samples. Malting resulted in almost 88%, 93% and 69% decline in peak viscosity for sorghum, maize and millet flours, respectively. Again, malting recorded the highest final viscosity reduction: about 97% in sorghum, 98% in maize, and 85% in millet flours. Malting and fermentation resulted in a reduced level of phytate, improved nutritional and functional properties in the cereals investigated. This study provides relevant information on the processing methods that can reduce phytate (antinutrient), relatively high in most cereals consumed in Ghana.