STUDY OF THE COMPATIBILITY INCOMPATIBILITY OF GELATIN/IOTA-CARRAGEENAN/WATER MIXTURES/

The incompatibility of acid gelatin/iota-carrageenan mixtures has been studied. Both these biopolymers undergo a conformational coil-helix t ransition under suitable conditions of temperature and salt. The aim o f this work was to study the concentration at which mixtures are incom patible and the influence of pH, salt and temperature on the phase dia gram. Incompatibility occurred over a wide range of concentrations for mixtures prepared in deionized water. Compatibility was increased by increasing the pH or the salt concentration. Temperature did not great ly influence the size of the incompatible region. This is in agreement with the hypothesis that attractive electrostatic interactions lead t o associative phase separation (traditionally called complex coacervat ion). Copyright (C) 1996 Elsevier Science Ltd.