β-Lactoglobulin-carboxymethylcellulose core-shell microparticles: Construction, characterization and isolation

The aim of this work was to build, to isolate and to characterize, core-shell microparticles composed of a core of thermally aggregated β-lactoglobulin (β-lg) covered by a shell of carboxymethylcellulose (CMC). The core-shell particles were obtained by mixing (β-lg)n and CMC solutions at pH 7 and finally, decreasing the pH up to 4, promoting the adsorption of CMC on the protein core due their opposite electric charge. The core-shell microparticles were characterized by static laser light scattering (SLS), optical microscopy and atomic force microscopy (AFM). At pH 4, (β-lg)n showed a diameter ∼200 nm, but after adding the polysaccharide had a diameter ∼1 μm. The microscopy corroborated the data obtained by SLS measurements. Core-shell microparticles could be isolated by lyophilization and potentially applied as a fat replacement and/or a delivery systems for encapsulated substances in food formulations.