CHARACTERIZATION AND ANTIOXIDANT CAPACITY OF ESSENTIAL OIL MICROCAPSULES FROM Campomanesia adamantium

Essential oils (EO) have expanded use and acceptability by the population, due to their relative safety and potential application in cosmetic, food, therapeutic fields. However, its volatility and susceptibility to degradation from high temperatures, humidity, light, and oxygen can result in the loss of aroma and decreased biological activity. These difficulties can be overcome by microencapsulation. The objective was to characterize EO microcapsules derived from residues (peels/seeds) obtained during the pulping of Campomanesia adamantium fruits, by the complex coacervation process followed by freeze-drying. Three formulations were prepared with different concentrations (%, w/w) of EO, which are: MC1 (33%), MC2 (43%), and MC3 (50%), using 1:1 ratio of gelatin and gum arabic encapsulants. MC2 and MC3 showed higher encapsulation efficiency (EE = 53% both) and lower hygroscopicity (H = 6.7%; 7.6%, respectively) than MC1 (EE = 47%, H = 11.6%), with a significant difference (p <0.05). The microcapsules showed no significant differences in mean diameter (45 – 49 µm), water activity (below 0.437), and water solubility (6.9 – 9.4%). Scanning electron microscopy indicated morphology with a smooth surface in MC1 and some pores in MC2 and MC3, possibly due to the high EO: encapsulant ratio. Thermogravimetric analysis indicated thermal stability of the microcapsules until 200 °C, while pure EO was wholly degraded at 250 °C. The observed characteristics are related to EO protection and lower volatilization in the studied encapsulation systems. Antioxidant capacity (AC) was evaluated by the ABTS•+ radical capture method, with microcapsules showing radical inhibition of 35% (MC1), 40% (MC2), and 51% (MC3), at a concentration of 1000 µg/mL. There was a greater AC with more incorporated EO, MC3 maintained 86% of the AC compared to pure EO. Microcapsules containing EO from C. adamantium demonstrate potential for food, therapeutic or cosmetic use, suggested by its characterization and antioxidant capacity