Hysteresis during sol-gel and gel-sol phase transitions of kappa-carrageenan: a photon transmission study

摘要

Photon transmission techniques were used to study sol-gel and gel-sol transitions in kappa-carrageenan-water systems with various carrageenan contents. The photon transmission intensity, I_(tr) was monitored against temperature to determine critical phase transition temperatures and transition rates. It was observed that the sol-gel transition temperatures, T_(sg), were found much than the gel-sol, T_(gs), transition temperatures based on the hysteresis of the phase transition loops. Sol-gel and gel-sol activation energies were determined and it was found that a carrageenan-water system required less energy for the gel-sol transition than for the sol-gel transition.