Effect of water content on thermal behaviors of common buckwheat flour and starch

Common buckwheat (Fagopyrum esculentum Moench) flour is widely used in food products due to its desirable taste, textural structure and nutrients. The effect of water content varying from ∼20% to ∼80% on the thermal behaviors of common buckwheat flour and its isolated starch was investigated by differential scanning calorimetry (DSC) from 40.0 °C to 105.0 °C and from −60.0 °C to 160.0 °C. The gelatinization temperature of buckwheat flour was between 60 °C and 85 °C and it decreased while the water content increased. Isolated buckwheat starch showed a narrower gelatinization range from 60 °C to 75 °C. To, Tp, Tc and ΔH of the ice melting peak of buckwheat flour and starch in the second scan increased as the water content increased. Their viscosity, crystallinity and retrogradation were also analyzed.