Preparation and characterization of montmorillonnite/carrageen/guar gum gel spherical beads

Composite gel spherical beads of carrageen and guar gum were prepared with a size range of 2 to 3 mm by adding montmorillonite (MMT) as a modifier for use in immobilised cell carrier technology. The interior structure and functional groups of the beads were characterised by XRD and FT-IR and the thermal stability of the beads was measured by DSC. The swelling kinetics of the composite gel spherical beads was studied. We pilot-studied living Saccharomyces cerevisiae cell immobilization and the effect of storage time on the cells' activity. The beads thermal stability was better than those of carrageen and guar gum because of the addition of MMT. The MMT made the beads form beautiful three-dimensional reticulated structures and improved their stability. It also reduced their solidification temperature and swelling ratio. The population of Saccharomyces cerevisiae on immobilised cells was about 70% of that at the beginning and was still 10(7) cells/g after storage for 3 months.