Revista mexicana de ingeniería química
Print version ISSN 1665-2738
C., Pérez-Alonso et al. Interrelationship between the structural features and rehydration properties of spray dried manzano chilli sauce microcapsules. Rev. Mex. Ing. Quím [online]. 2009, vol.8, n.2, pp. 187-196. ISSN 1665-2738.
Manzano chilli sauce microcapsules (MCHS) were obtained by spray drying using Gum Arabic (GA100%), whey protein concentrate (WPC100%) and a blend of these biopolymers (GA50%-WPC50%) as wall materials in 2:1 and 4:1 wall to core material ratios (WCMR). Water vapor adsorption isotherms data of microcapsules were obtained at 35 °C and fitted to GAB's model. The monolayer water content values of the microcapsules varied from 9.97 to 14.32 kg H2O/100 kg dry solids, and were used for determining the surface fractal dimension (Ds). Ds values ranged between 2.04 to 2.30 for the 2:1 WCMR and 2.17 to 2.43 for the 4:1 WCMR, respectively. Microcapsules topology was determined by Scanning Electronic Microscopy (SEM). Microcapsules with WPC100% exhibited smoother and more regular shaped topology than those with GA100% which tended to exhibit surface flaws and dents, while those made with the biopolymers blend exhibited an intermediate morphology. Rehydration times of the microcapsules were function of water activity (aw) and WCMR. The higher the WCMR, the higher the rehydration time required.
Keywords : fractal dimension surface; sorption isotherms; water activity; microencapsulation; topology; structural features.