Insoluble dietary fiber and microparticle formation from olive pomace: effects on emulsification and interfacial behavior in Pickering emulsions

Abstract

In this study, we systematically produced particles and insoluble dietary fibers (IDFs) with varying particle sizes from olive pomace, a by-product of olive oil manufacturing, and conducted an extensive characterization of their physicochemical, technological, and structural properties. These materials were then utilized in the formulation of Pickering emulsions, facilitating an investigation into the correlation between particle characteristics and emulsion stability. Emulsions formulated with IDFs exhibited ζ potential values exceeding − 20 mV and displayed minimal fluctuations in particle size. The lowest interfacial tension, indicative of maximal adsorption at the oil–water interface, was observed in olive pomace fiber (OPF) (37.01 mN/m at 10 s). With time, the interfacial tension of all emulsions decreased, suggesting continuous particle adsorption at the oil–water interface. Additionally, Pickering emulsions stabilized by IDFs demonstrated significantly higher θ values, highlighting their superior emulsification efficacy in enhancing Pickering emulsion stability. This investigation lays the groundwork for the development of stable Pickering emulsions utilizing olive pomace, a by-product of olive oil production, and for the comprehensive utilization of olive oil waste. Overall, these findings suggest that the incorporation of olive pomace IDFs holds substantial promise in enhancing the stability of Pickering emulsions.