Physicochemical properties of etherified maize starches

The changes in starch properties due to etherification with allyl glycidyl ether (AGE) have been investigated. After etherification of three different starches (containing 0.9%, 27% and 70% amylose), no appreciable differences in granular appearance were observed, but the granule crystallinity of these starches was changed. Furthermore, the incorporation of AGE in the starch significantly affects its physicochemical properties: the gelatinization temperatures were decreased and the pasting properties were altered. Both the swelling power and the solubility index increased as the degree of substitution (DS) increased. The rheology behaviour of the droplets of swollen granules suspension was studied under shear flow conditions.