Gelation and Its Related Changes in Amylose Solution

The phase change for an amylose solution in the binary solvent system of dimethylsulfoxide (DMSO) with water was investigated under various conditions from sol to gel. The phase change was determined with measurements of the fluorescent depolarization and other methods by varying the solvent constitution at 25°C, and then varying the temperature at 10% of DMSO concentration.

The phase diagrams obtained with both variables were substantially similar and were also similar to those for an aqueous agarose solution. This similarity in phase diagram suggests a similar gel formation mechanism of amylose to agarose.

It was found that the phase separation point for the amylose solution agreed with the gel formation point and also with the starting point of retrogradation.