Influence of the polarity of the water phase on the mesomorphic behaviour and the α-gel stability of a commercial distilled monoglyceride

摘要

The lyotropic mesomorphic behaviour of a commercial distilled monoglyceride based on fully hydroge-nated palmstearin at a concentration of 25% was studied as a function of temperature. Differential scanning calorimetry and wide angle X-ray diffraction were used to determine the Krafft temperature. Polarized light microscopy and small angle X-ray scattering were used to analyze the lamellar dispersion to an inverted bicontinuous cubic phase transition. The addition of a polar solvent, namely ethanol, pro-pylene glycol and glycerol shifted the lamellar dispersion region to lower temperatures. The composition of the water phase also played an important role in the stability of the α-gel that was obtained by cooling the lamellar dispersion. In fact, the stability of this metastable phase as expressed by the coagel-index determined by differential scanning calorimetry was negatively influenced by decreasing the water phase polarity.