Surface modification of zein colloidal particles with different gums to stabilize Pickering emulsions

In this study, zein, the primary storage protein in corn seeds, was used to synthesize colloidal particles as emulsion stabilizers. Surface modification of zein particles was performed using different polysaccharides (carboxymethyl cellulose (CMC), water-soluble portion of Persian gum (WPG), and gum Arabic (GA)) through two fabrication methods: matrix (MT) and core-shell (CS), in order to create composite particles with enhanced ability to stabilize Pickering emulsions. The composite particles exhibited negative surface charge values at pH 4, indicating the presence of polysaccharides surrounding the zein cores. All particle dispersions had a viscous nature, with those containing CMC exhibiting the highest viscosity. The emulsions stabilized by zein/WPG particles fabricated using the MT method and zein/CMC particles fabricated using the CS method demonstrated the highest stability during 42 days of storage, while GA did not improve emulsion stability. The droplet sizes of the emulsions were in the micrometer range, with a low negative surface charge. For the emulsion stabilized by composite CMC particles, G' was greater than G", while for those containing WPG, G' and G" values were almost equal. All samples exhibited shear-thinning properties. The addition of curcumin (Cu) to the zein/WPG (MT) particles improved emulsion stability slightly.