Hydrothermal characteristics of pearl millet (Pennisetum glaucum) flour during cooking into ‘fura’

The effects of hydration times (HT) (1, 3.5 and 6 h) and cooking times (CT) (20, 40, and 60 min) on the thermal characteristics of cooked pearl millet flour (CPMF) was investigated. The differential scanning calorimetry thermograms depicted two separate endothermic transitions identified as starch gelatinisation (29 to 30°C) and disruption of the starch-lipid complexes (90 to 120°C). HT gradually decreased the degree of gelatinisation, whereas, CT drastically increased the degree of gelatinisation. Hydrating millet flour for 1 h and cooking for 40 min was sufficient to achieve 100% gelatinised flour. Starch-lipid complex formed after gelatinisation at hydration time (3.5 h) and cooking for 40 min. Increasing both the HT and CT reduced the amount of energy required to break the starch-lipid complex formed during the cooking of millet flour. The UPMF showed a typical A-type X-ray diffraction pattern, which was altered by the hydrothermal treatments (1 h hydration and 20 min cooking) resulting in a transformation into the V-hydrate form evidence of starch-lipid complex formation. The formation of this complex possibly explains why millet flour remains intact during cooking into fura.