Mechanical and optical characterization of gelled matrices during storage

LORENZO G.; ZARITZKY NOEMI.; CALIFANO A

CARBOHYDRATE POLYMERS

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2015 vol. 117 p. 825 - 835

0144-8617

The effect of composition and storage time on the rheological and optical attributes of multi-component gels containing locust bean gum (LBG), low acyl (LAG) and high acyl (HAG) gellan gums, was determined using three-component mixture design. The generalized Maxwell model was used to fit experimental rheological data. Mechanical and relaxation spectra of gelled systems were determined by the type ofgellan gum used, except LBG alone which behaved as a diluted gum dispersion. Storage time depend-ence of the gels was analyzed using the rubber elasticity theory and to determine changes in networkmesh size the equivalent network approach was applied. Destabilization kinetic was obtained from light scattering results; increasing LAG content improved the long-term stability of the matrices. Almost every formulation exhibited an increment in both moduli during the first 10 days remaining practically constant thereafter or until they broke (binary mixtures with LBG); gels with HAG/LBG mixtures were the least stable.