The Influence of Xanthan Gum on Rheological Properties and In Vitro Digestibility of Kudzu (Pueraria lobata) Starch

The study describes the effects of xanthan gum (0.5-2.0%) on the in vitro digestibility and rheological and pasting properties of kudzu (Pueraria lobata) starch pastes. The flow behavior index (n) shows a decrease in trends (from 0.43 to 0.31) as the xanthan gum concentration increases, indicating pseudoplastic behavior. Dynamic viscoelasticity analysis indicate that the elastic (G ') and viscous (G '') moduli increase in the presence of xanthan gum, suggesting a strong interaction between xanthan gum and kudzu starch in the composite system. All concentrations of xanthan gum result in increased elasticity (G ' > G ''). Pasting properties reveal that the peak and final viscosity of the xanthan gum-kudzu starch dispersion decreases with the increasing concentration of xanthan gum, highlighting the importance of xanthan gum in controlling overall viscosity. The addition of xanthan gum also decreases the hydrolysis of kudzu starch during in vitro digestion.