Gelatinisation of starch: a combined SAXS/WAXS/DSC and SANS study

Using a combination of techniques, small- and wide-angle X-ray scattering, differential scanning calorimetry and small-angle neutron scattering, it has been possible to follow the stages that occur during gelatinisation in excess water for a range of starches. It is found that water enters the amorphous growth rings first, and that this is where all the swelling is concentrated. The periodicity of the semicrystalline stack remained unchanged as long as the crystallites can still be identified. As the temperature is raised further through the gelatinisation endotherm, the crystallites become destabilised and the crystallisation index drops to zero, rather beyond the end of the endotherm revealed by DSC.