Effect of Soaking Treatment on the Gelation Properties of Rice Starch

In order to study the effect of soaking treatment on the gelation properties of rice starch, the effects of different soaking times on the gelatinization and rheological properties of rice starch were investigated by means of rapid viscosity analyzer (RVA) and rheometer. The RVA curves showed that the peak viscosity and the breakdown of rice flour increased significantly with the soaking time (p<0.05), and the final viscosity and setback first increased and then decreased, and the gelatinization temperature decreased. Rheological experiments showed that the yield stress, shear stress and apparent viscosity of rice starch after soaking treatment were higher than those of untreated rice starch. With the prolongation of soaking time, the G'max, G'_95℃, G'_25℃, tanδ_25℃ and K'_G showed a decreasing trend, which indicated that soaking treatment could significantly affect the strength of rice starch gel, and improve the stability of the gel.