The influence of different sterilization procedures on alginate dispersions was studied by measuring viscosity and molecular weight changes. Autoclaving caused a 64% decrease in viscosity. Heating at a low temperature over several cycles was less efficient in sterilizing alginates and there was a progressive breakdown of the alginate chain over the succeeding cycles. Heating during ethylene oxide sterilization also resulted in reduced viscosity and breakdown. Membrane filtration yielded a sterile product with no significant reduction in viscosity or mol. wt.