THE USE OF IMAGE-ANALYSIS AS A MEANS OF MONITORING BUBBLE FORMATION IN ALGINATE RAFTS

The use of image analysis as a means of measuring the dimensions of bu bbles produced using a range of alginate raft formulations is describe d. Raft-forming mixes containing three sodium alginate samples (LFR 5/ 60, LF 120M and LF 10/40RB) were prepared, using sodium and potassium bicarbonate as gas-generating agents, and calcium and zinc carbonates as sources of divalent cations. The perimeters, areas and mean diamete rs of the bubbles were ascertained and an index described whereby the sphericity of the bubbles may be quantified. Systems produced using LF R 5/60 were found to produce the largest bubbles overall. Comparison w ith rheological studies indicated that this alginate sample produced t he lowest viscosity mixes, suggesting a correlation between the viscos ity of the medium in which the bubbles form and the subsequent bubble size. (C) 1998 Elsevier Science B.V. All rights reserved.