Morphological, Thermal, and Rheological Properties of Starch from Potatoes Grown in Mexico

The morphological, thermal, and rheological properties of potato starch from three cultivars in the State of Sonora, Mexico, are evaluated. Content of starch, moisture, purity, and amylose vary from 11.8% to 14%, 9.2% to 11.2%, 78.2% to 83.0%, and 20.0% to 29.9%, respectively. The size and shape of the starch granules are similar among the cultivars. The granules show birefringence, which indicates the presence of a structural arrangement of their components (amylose and amylopectin). The highest peak temperature is observed in “Fiana” starch (67.0 ± 0.3 °C), even though gelatinization enthalpy is similar for the three starch sources (9.1 to 10.1 J g⁻¹), indicating a similar arrangement of the double helixes of the amylopectin. The percentage of retrogradation is highest in “Vivaldi” starch (38.2%), which is similar to “Atlantic” (32.1%). Regarding the pasta profiles, the highest viscosity is as found in “Vivaldi” starch (95.1 mPa s⁻¹). Due to its physicochemical properties, isolated starches produced from potatoes grown in Mexico have the potential to be used in industrial applications.