2005 年 33 巻 4 号 p. 167-172
Enzymatically synthesized completely linear α-1,4 gulcan amylose (ESA) with various molecular weights was dissolved in water and alkaline solution. Change in the solution rheology with time after preparation was investigated. Both |η*| and G' of low molecular weight ESA in alkaline solution increased with increasing time after preparation due to the formation of crosslinking at the crystallites. Medium molecular weight ESA tended to degrade and the solution viscosity decreased with time in the alkaline solution. However the zero shear viscosity did not decrease to the value predicted from η0 = KM 3.4 relation when the concentration is high. High molecular weight ESA dissolved in water was not subjected to the degradation and show the significant increase in |η*| and G' due to the retrogradation.
