Retrogradation and gelling behaviours of partially gelatinised potato starch as affected by the degree of pre-gelatinisation

This study explored the gelling and structural properties of partially gelatinised potato starch before and after reheating in response to their initial degree of starch gelatinisation (DSG). The retrogradation R and setback of starch increased from 4.18 to 17.14 and 179 to 579 mPa center dot s, respectively, with increasing initial DSG from 56.11% to 90.56%. The starch gel strength increased, whereas the short-range ordered structure decreased as DSG increased without reheating. After reheating, the starch gel strength with relatively low initial DSG (56.11%) was 2.4 times higher than that of native starch and 1.7 times higher than that of starch with high DSG (90.56%). The interspersed starch granules in gels without reheating affected the formation of the network. After reheating, all gel samples formed a honeycomb structure with increased porosity as DSG increased. This could be related to the different degrees of dehydration synthesis of starch with different DSGs during retrogradation.