A LIGHT-SCATTERING STUDY OF CARRAGEENAN GALACTOMANNAN INTERACTIONS/

New experimental results that support the formation of mixed aggregate s in the carrageenan/galactomannan system are presented. Kappa- and io ta-carrageenan were degraded by ultrasonication to obtain low molecula r weight samples. These samples were mixed with galactomannan in vario us proportions and studied in dilute solutions by multi-angle laser li ght scattering. Two different galactomannans were used, locust bean gu m and guar gum. The ion specificity of the carrageenans was used to co ntrol their conformation and association. This made it possible to sep arately study how double helices and aggregates interact with the gala ctomannans. Under self-aggregated conditions, kappa-carrageenan was se en to associate with locust bean gum, but not with guar gum. Iota-carr ageenan did not show any signs of association under any conditions.