Propolis Complexation by Using Egg White Protein Nanocarriers: Molecular, Antioxidant, and Interfacial Properties

Abstract

This study aims to encapsulate propolis ethanolic extracts (PE) using egg white protein nanoparticles (EWPn) and assess their impact on the molecular, antioxidant, and interfacial properties of the formed nanocomplexes obtained by an antisolvent technique. Four PE samples from different regions of Argentina (Santiago del Estero, Mendoza, and Tucumán) were obtained and characterized using GC-FID/MS analysis, total phenolic content determination, and total flavonoid content assays. The EWPn-PE systems were analyzed through fluorescence, UV–vis spectroscopy, particle size, ζ-potential, antioxidant activity, encapsulation efficiency, and interfacial studies. The results highlighted significant variability in the chemical composition and properties of the PE samples, influenced by geographical and botanical factors. The antioxidant activity of the EWPn-PE systems was significantly enhanced compared to the free PE, suggesting that EWPn complexation stabilizes and protects the phenolic compounds. The interfacial properties, including the diffusion, penetration, and rearrangement rate constants of EWPn, were also influenced by the complexation with PE. The EWPn-PE2 system exhibited the most favorable interfacial properties, suggesting its potential for stabilizing colloidal dispersed foods such as foams and emulsions. Overall, these findings highlight the effectiveness of EWPn complexation in enhancing the functional properties of PE, offering new opportunities for their application in the food industry.