Abstract:Potato starch has attracted much attention owing to its large particle size, low gelatinization temperature, high viscosity, and strong gelatinization. A total of 11 varieties of potatoes from Heilongjiang, Gansu, and Beijing were selected as the research objects for comparative analysis of differences in amylose content, starch granule size, thermal properties, microstructure characteristics, viscosity, and rheological properties among starch made from different varieties of potatoes, as well as correlation analysis between microstructure characteristics and physicochemical characteristics of different starch varieties. The results showed that Burbank had the highest amylose content of 16.64%, and the D50 values of different varieties of starch ranged from 59.40 to 323.90 μm. Dutch potatoes had the highest initial gelatinization temperature, peak temperature, and gelatinization enthalpy, with starch granules mostly circular or elliptic. Longshu 9 had the lowest gelatinization temperature of 62.27 ℃, while the storage moduli of Long 14 and Longshu 7 were significantly higher than those of other varieties. D50 was significantly positively correlated with gelatinization enthalpy (r=0.596 3) and gelatinization temperature (r=0.502 4), but significantly negatively correlated with amylose content (r=-0.576 5) and retrogradation value (r=-0.551 8). Among starch thermal properties, initial gelatinization temperature was significantly positively correlated with the peak temperature (r=0.961 0), peak time (r=0.733 6), and gelatinization temperature (r=0.933 9) of viscosity properties. A significant correlation was observed between the microstructure and physicochemical properties of starch made from different varieties of potatoes, thus providing a basis for the processing and utilization of potato starch as well as potato breeding.
