Effect of fermentation conditions on nutritional and phytochemical constituents of pearl millet flour (Pennisetum glaucum) using response surface methodology

Abstract

In the current study, fermentation conditions for pearl millet flour were optimized using baker's yeast. A central composite experimental design with three independent variables, temperature (30°C-45°C), yeast concentration (2%–4%) and time (18–24h) was used to study the dependent variables (total protein, total sugar, total phenolics, total flavonoids, total Titratable acidity, total soluble solids and pH). Based on response surface methodology, twenty run were processed. Regression model interpretation revealed the significant relationship between considered dependent and independent variables. Also all linear terms, two quadratic terms (fermentation temperature and time) and all interactive terms had significant (p<0.05) effect on the response variables. The optimum fermentation condition for pearl millet flour was achieved with 2% baker's yeast at 30°C for 18h. Fermentation at this condition significantly improved the phytochemical constituents of pearl millet flour. Thus, this pearl millet flour with improved phytochemical constituents can be used to develop healthy functional food products by food industries.