A rapid method for determining sphericity of hydrocolloid beads

Estimation of deviations from sphericity is important in the study of mass and heat transfer from beads used for biotechnological operations. The sphericity of alginate beads was estimated by two techniques: a method originally developed for quartz grains expresses the shape character of the bead relative to that of a sphere of the same volume and a method previously developed for convex bodies calculates a dimensionless constant which relates surface area to volume. Deviations from sphericity were estimated easily by the former. The latter, although more laborious, provides measurements that influence the results less. The difference between the two procedures for estimating bead sphericity was not more than 5%. Deviations from perfect sphericity are ∼7% for tested alginate beads under examined conditions.