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A response surface methodological design was adopted to
investigate the effects of storage conditions on the
structure of xanthan gum/gelatin complexed gel by using
rheometry and differential scanning calorimetry ( DSC ).
Furthermore, the oil /water emulsion model system prepared by
the xanthan gum/gelatin complex was proposed to study the
effects of molecular realigning processes during storage on the
thermal stability and the micro- wave heating characteristics
of the emulsion system. Results of the rheometrical
compression test showed that both hardness and modulus of
elasticity of the xanthan gum/gelatin complexed gels
increased as the increases of storage time and
temperature. Thermal properties of the freeze-dried xanthan
gum/gelatin com- plexed gel were further analyzed by DSC.It
was also observed that the endothermic melting peak of gelatin
occurred between 65℃ and 90℃,whereas the exothermic
decomposition peak of the xanthan gum /gelatin complexed gels
was observed between 155℃ and 220℃. The endothermic onset
melting temperature observed to be linearly related to both
of the storage time and temperature. The endo- thermic peak
melting temperature was quadratically related to the storage
time and temperature. Besides, the exothermic enthalpies
increased as the increases of storage time and temperature.
Ther- mal stability and the microwave heating characteristics
of the emulsion model system could also be improved by
molecular realig- ning processes when it prepared by using the
xanthan gum/gelatin complexes.
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