QUANTIFICATION OF WATER IN CARBOHYDRATE LAMELLAE USING SANS

The ingress of water into polymeric carbohydrate systems which contain alternating crystalline and amorphous lamellae is of wide interest. T he small-angle neutron scattering profile resulting from the interacti on between the lamellae and water is modelled with a Hosemann-type par acrystal. Coupled with the use of contrast variation, it is possible t o quantify the amounts of water and carbohydrate in the different regi ons of the system. The technique is applied in a study of the hydratio n of waxy maize starch. In addition data is presented on the dynamic g elatinisation of starch in situ in a pulsed neutron beam.