Sameness and difference of rheological behaviour between sweet potato and mung bean starch pastes

The rheological property of starch paste is important for mixing, forming, droping and shaping of starch dough in the processing of starch noodles. The rheological behaviour of sweet potato starch paste (SPSP) and mung bean starch paste (MBSP) were measured at different concentrations, temperatures, shear rates and temperature ramps. Results show that the two starch pastes have similar thixotropy, which is characteristic of an unclosed hysteresis loops with different areas in corresponding flow plots. The rheological behaviour of starch pastes are explained better by Cross equation than by Power Law equation. Both pastes are temperature-sensitive and suitable for Arrhenius equation. However, the area of hysteresis loops of SPSP at different conditions are smaller than those of MBSP, indicating that SPSP is more viscous continuously than MBSP in the formation of starch dough. The zero-shear viscosity of MBSP is lower than that of SPSP, but there is no obvious difference between them at lower concentration (≤8%). Therefore, it is feasible to use SPSP, instead of MBSP as adhesive agent in the processing of starch noodles.