Propolis microencapsulation by complex coacervation using whey protein and gum arabic: An approach to the assessment of the stability and controlled release of phenolic compounds

The aim of this study was to microencapsulate the propolis extract via complex coacervation using whey proteins and gum arabic, followed by oven drying. It assessed encapsulation efficiency, yield, morphology, and physicochemical properties of the microparticles, including moisture content, water activity, bulk density, hygroscopicity, and dispersibility. Antioxidant activity was determined in both free and encapsulated extracts, and the stability of bioactive compounds was evaluated over 90 days at −75 and 25 °C. The release profile of phenolic compounds was assessed in acidic and neutral media. The encapsulation process showed high efficiency (80.3%) and yield (74.3%), producing microcapsules with an average diameter of 3.14 µm, 6.7% moisture content, 0.30 water activity, 0.56 mg/mL bulk density, 3.2% hygroscopicity, and 25% water dispersibility. Microencapsulation effectively maintained the antioxidant activity of propolis extract. The stability of the bioactive compounds was influenced by temperature, with a more pronounced reduction in flavonoid content (86%) at room temperature and better retention of phenolic compounds (15%) at −75 °C. The release profile of phenolic compounds was similar in acidic and neutral media, with higher retention (62%) in the neutral medium. These findings highlight the potential of encapsulated propolis extract as a food additive.