Structure-rheology relationships of composite gels: Alginate and Basil seed gum/guar gum

Structure-rheology relationship of binary composite gel (BCG) systems of alginate/guar gum and basil seed gum/guar gum at ratio 2:1 at different Ca2+ levels (2-10%) were evaluated. The highest value of structural strength was obtained at 2 % of Ca2+, which can be attributed to its stronger network as assessed by rheological experiments. Mechanical spectra of the alginate/guar gels explained pseudoplastic behavior with a highly interconnected elastic gel structure. The mechanical strength as well as other textural properties of the alginate and basil seed gum network was functions of its stoichiometry with calcium ions. Whereas alginate/guar gels showed an elongated globular denser structure as determined by SEM, the BSG/guar gels showed a rigid cubic as the pieces of a puzzle, presenting a softer and weaker gel structure. The alginate/guar gels showed less porosity without syneresis or shrinkage during storage as supported by its high elasticity and rigidity.