Effect of frozen storage on the physicochemical properties and thermodynamic properties of wheat starch

The morphology, physicochemical properties, thermodynamic properties and retrogradation characteristics of wheat starch were studied by frozen storage. Frozen wheat starch granules was detected by scanning electron microscopy ( SEM) , which found that some of the starch granule surface damage.The frozen wheat starch solubility, viscosity, swelling power, blue values were measured, and the results showed that frozen storage starch solubility and viscosity increased 48.6% and 43.2%, and swelling power, blue values were decreased 8.41%, 28.5%. The thermodynamic properties of frozen wheat starch were measured by differential scanning calorimetry ( DSC) , and found the enthalpy and the temperature range of gelatinization decreased by47.3% and 10.60%.The retrogradation value decreased by 47.2%. The results showed that morphology, physicochemical properties, thermodynamic properties were changed significantly for frozen wheat starch.