Preparation and characterization of dressing-type emulsions formulated with hydrocolloids from the mango (Mangifera indica) peel

Abstract

Mango is a popular tropical fruit known worldwide and mango peel is a waste product worthy of valorization. This study explores the stabilizing effect of hydrocolloids extracted from mango peel in dressing-type emulsions (DE). Emulsions stabilized with different ratios of mango (Mangifera indica) peel-derived hydrocolloids (PE) and guar gum (1 % wt. total concentration) were prepared and characterized: DE1 (0.25/075), DE2 (0.5/0.5), DE3 (0.75/0.25) and DE4 (1/0). Particle size distribution, zeta-potential, proximal composition, color, microstructure, and rheological properties were evaluated. All the samples showed similar proximal compositions. However, PE/ guar gum ratio influences color parameters. For the microstructural analysis, Sauter’s mean droplet size ranged from 6.41 to 11.11 μm. The zeta- potential values ranged from -18.03±0.21 to -16.97 mV. Emulsions exhibited shear thinning responses that can be well described by the Williamson model, and gel-like viscoelastic character with G’ higher than G”. The activation energy values (Eα) deduced from the application of an Arrhenius model to the viscous flow behaviour of the emulsions ranged from 108.46 to 143.44 Kj/mol. From the microstructural analysis and the rheological characterization, it can be inferred that PE favors the flocculation of the emulsion droplet in high concentrations. Overall, this research contributes to the sustainable exploitation of a mango waste material, such as the peel, in food emulsions.