Phase Separated Structures of Mixed Carrageenan Gels Elucidated Using Particle Tracking

摘要

The phase separated structure of mixed k-(KC) and l-(IC) carrageenan gels were elucidated using dynamic rheological measurements and particle tracking for probe particles with diameter of 100 nm. Particle tracking was utilized to investigate the gelation mechanism and network structure of the mixed gels during cooling at 1 and 0.005 °C/min and after 1 day storage at 5 °C. The mean square displacement (MSD) of particles in the mixed gels was used to characterize the changes in the microscopic physical property of the gels. The individual MSD of particles in the mixed gel after 1 day storage showed a large distribution indicating a microstruc-tural heterogeneity which proposed the formation of phase separated structure with KC-rich and IC-rich network domains. Interestingly, a significant splitting in the individual MSD was observed using 0.005 /min cooling rate suggesting an enhanced phase separated structure.