Rheology and DSC of Gellan-Agarose Mixed Gels

  • K. Nishinari
  • T. Takaya
  • M. Watase

Abstract

The rheological and thermal properties of mixed gels of gellan and agarose were studied by dynamic viscoelastic measurement and differential scanning calorimetry (DSC). E’ increased slightly up to a certain temperature To and then began to decrease with increasing temperature. This temperature To shifted to higher temperatures with increasing gellan content. The critical concentration for gelation Co becomes higher with increasing gellan content. Two endothermic peaks were observed in DSC curves for mixed gels. The higher temperature peak was attributed mainly to the melting of gellan gum network whilst the lower temperature peak was mainly attributed to the melting of agarose network. In the phase separated gels, gellan forms at first a network on cooling, and then agarose forms another network at lower temperatures.

Keywords

Urea Carbohydrate Agarose Mold Polysaccharide 

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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • K. Nishinari
    • 1
  • T. Takaya
    • 2
  • M. Watase
    • 3
  1. 1.National Food Research InstituteTsukubaJapan
  2. 2.Department of Food and NutritionFaculty of Science of Living Osaka City UniversityiSumiyoshi, OsakaJapan
  3. 3.Chemical Research LaboratoryFaculty of Liberal Arts Shizuoka UniversityOhya, ShizuokaJapan

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