Development and Characterization of Lipid Micro- and Nanoparticles for the Encapsulation of Pomegranate Seed Oil

The aim of this study was to produce and characterize micro- and nanoparticulate lipid carriers for pomegranate seed oil (PSO) to preserve its functional properties. The results of the dynamic light scattering (DLS) technique revealed that formulation proportions minimally affected particle size, with lipid nanoparticles (LNs) ranging from 308 to 325 nm, and LN4:1 being the most monodisperse formulation. Lipid microparticles (LMs) ranged from 1251 to 4364 nm, demonstrating the efficiency of hot homogenization with rotor–stator for micrometer-sized particles. SEM analysis further confirmed the morphology, showing well-defined spherical shapes and the presence of particle clusters, likely due to the lyophilization process and the lipid nature of the carriers. All formulations exhibited stable dispersion (high negative zeta potential). Formulations with greater color difference (ΔE*) and a lower polydispersity index (PDI), such as LN4:1, indicate more effective oil homogenization and enhanced protection of the oil and its bioactive components. Compatibility and preservation of PSO characteristics were confirmed by XRD and FTIR. Encapsulation efficiency values for the formulations ranged from 40.0% to 66.1%, indicating satisfactory oil encapsulation. Furthermore, the encapsulation process effectively protected the antioxidant activity of PSO, with a decrease in the DPPH scavenging percentage from 55.4% (free PSO) to values ranging from 41.4% to 51.3% (lipid carriers). Overall, this study demonstrates the feasibility of producing PSO micro- and nanoparticles with the methods employed, suggesting applications in sustainable packaging.

Practical Applications: The development of lipid micro and nanoparticles for the encapsulation of pomegranate seed oil (PSO) offers significant potential in the food industry, particularly for creating biodegradable active packaging. Encapsulation enhances the stability of bioactive compounds, including punicic acid, tocopherols, and polyphenols, protecting them from oxidative degradation. This preservation improves the shelf life and functional properties of food products. Additionally, the controlled release mechanism of these lipid carriers can enhance the bioavailability of PSO's antioxidants, contributing to improved nutritional value and health benefits. These findings suggest potential applications in the formulation of functional foods, nutraceuticals, and packaging solutions that maintain the quality and safety of food products over time.