On the interaction between konjac glucomannan and xanthan in mixed gels: An analysis based on the cascade model

► Synergistic gelation of konjac glucomannan and xanthan. ► We analyze the gelling behavior with a two-component cascade model. ► Konjac glucomannan has a functionality (number of binding sites per chain) value of 3. ► The heterotypic binding has a high enthalpy/entropy ratio (5.52). ► We propose that the binding of konjac glucomannan with xanthan takes place on consecutive glucose residues. The rheological properties and critical behavior of konjac glucomannan (KGM)/xanthan (XG) mixed gels were investigated and analyzed using a two-component cascade model. The fitting results show that the optimal functionality value for KGM (fKGM) is 3, whereas the possible functionality value for XG (fXG) is 100–1000 obtained from the modulus data, or 25 obtained from the critical data. The van’t Hoff analysis of the critical data shows that the binding of KGM with XG has a high enthalpy/entropy ratio (ΔH/300ΔS=5.52), which can be explained by the gain in the hydrational entropy due to the release of water molecules during the binding reaction. From these results, we proposed that the binding of KGM with XG takes place on the consecutive glucose residues of KGM with six or more units.