Gelatinisation properties of native and annealed potato starches

The relationship between the gelatinisation parameters of native and annealed starches extracted from ten different potato varieties grown at the same site at the same time was studied. The objective was to identify how native gelatinisation temperatures and enthalpies impacted on annealed starch gelatinisation parameters. Prior to ANN, the initial onset (To), peak (Tp) and conclusion (Tc) gelatinisation temperatures ranged from 58.71 to 62.45, 62.52 to 66.05 and 68.67 to 72.27 degrees C, respectively, which increased to 66.15 to 69.12, 70.22 to 72.30 and 76.21 to 77.44 degrees C, respectively, post ANN. Overall, the greater the initial gelatinisation temperatures the smaller the increment (?GT) post ANN. Comparable enthalpy values pre- and post-ANN were 15.13 to 18.37 and 15.76 to 18.37?J/g, respectively. These data indicate that the more perfect the crystallites were before ANN the less they could be enhanced by the ANN process and that against a constant background of a-glucan structure, the pattern (rate) of starch deposition might be the primary differentiator of starch architecture across the varieties.