The Interaction Between Surfactants and 2‐Hydroxy‐3‐(N,N‐dimethyl‐N‐dodecylammonium)‐propyloxy Starches

The phase behavior of temperature‐responsive hydrophobically modified starches and the interaction between oxidized potato amylose and hydrophobically modified potato amylopectin have been investigated by rheology, turbidity measurements and differential scanning calorimetry. When oxidized amylose was mixed with hydrophobically modified amylopectin, a viscosity peak was observed, indicative of a guest‐host interaction between the oxidized amylose and the hydrophobically modified amylopectin. A series of oxidized and hydrophobically modified potato starches were investigated in the presence of an anionic and cationic surfactant. A coil‐helix transition of the investigated starches was observed in the presence of surfactant, with the exception of a cationic surfactant combined with a hydrophobically modified zwitterionic starch of high positive net charge. The destabilizing mechanism (the phase separation) of the hydrophobically modified starches was studied as well as the difference in stabilizing capacity between the investigated cationic and anionic surfactants.