電解質多糖ジェランガム水溶液のゲル化機構

抄録

Polysaccharide gellan gum forms transparent, heat, and acid resistant gels. In the present paper, recent studies on gelation mechanism for gellan gum aqueous solution are reviewed. Using sodium, lithium, potassium, and tetramethyl-type gellan gums as samples, viscometry, osmometry, and differential scanning calorimetry, and light scattering and circular dichroism measurements were carried out in aqueous solutions with and without salts. On lowering temperature, gellan gums undergo a coil to double-helix conformational transition in aqueous solutions with and without salts and a sol to gel transition took place by aggregation of double-helical gellan gum molecules. Attention is especially paid to the effects of molar masses of gellan gum molecules on the coil to double-helix transition and the sol-gel transitions in aqueous solutions. Effects of cations on these transitions of gellan gums in aqueous solutions are also mentioned.