• AP;
  • Asymmetrical flow field-flow fractionation;
  • Hydrodynamic radii;
  • Microwave reactor;
  • wx Corn starch


Hydrodynamic properties of aqueous wx corn starch (native, un-pregelatinised) dispersions treated in a dedicated single-mode microwave reactor at temperatures ranging from 180 to 210°C were determined using asymmetrical flow field-flow fractionation coupled with an RI detector. The dedicated microwave reactor enabled the fine control and monitoring of heating parameters (especially temperature) during the treatment. The translational diffusion co-efficient and hydrodynamic radii (Rh) values determined for wx corn starch treated at 180 and 200°C indicate that the majority of the material (∼98%) consisted of highly mobile, small and compact molecules/particles, with Rh values ranging from 10 to 90 nm, while the remaining ∼2% of the material consisted of considerably larger molecules/particles Rh values ranging from ∼100 to ∼200 nm). Degradation of wx corn starch was observed at 210°C.