Microcrystalline parameters in native and acid-modified starches.

Crystallite size and lattice distortion parameters of starches from cereals, millet, pulse, root and
tuber before and after acid modification were determined by wide angle X-ray scattering (WAXS) studies. The
(hkl) planes and cell parameters were obtained using a minimization program. Acid modification results in
minor changes in d-spacing but there is considerable change in microcrystalline parameters, which has been
reported here. Using these data, we have also estimated the changes in the mean shape of the coherent domains
in terms of the shape ellipsoid in these starches for various types of acids treatment.