Prediction of the effect of sucrose on equilibrium swelling of starch suspensions

Equilibrium swelling of 8 wt % suspension of waxy (WMS) and normal (NMS) maize, waxy(WRS) and normal(NRS) rice when heated to 80 °C at different sucrose concentrations (0–30 wt %) were characterized. The swelling power reached maximum values of 10.5 and 14.5 at sucrose concentration of 5 wt % and 10 wt % for NMS and WRS respectively, increased with sucrose concentration for WMS from 11 to 15.5 and decreased for NRS from 11 to 8.2. The onset temperature of gelatinization increased with sucrose concentration for all starches whereas enthalpy of gelatinization increased for normal maize starches and did not vary significantly for waxy starches. The interaction parameters for three component system of starch, water and sucrose were inferred from static light scattering. The predicted equilibrium swelling for all starches at different sucrose concentrations using Flory-Huggins theory agreed well with experimental data.