Microencapsulation of Rosemary Essential Oil: Characterization of Particles

This study evaluated the influence of wall material concentration (10-30%), inlet temperature (135-195 degrees C), and feed rate (0.5-1.0L center dot h(-1)) on the properties of rosemary oil microencapsulated by spray-drying, with gum arabic as carrier. Powder recovery, surface oil, oil retention, and hygroscopicity varied from 17.25%-33.96%, 0.03%-0.15%, 7.15%-47.57%, and 15.87%-18.90%, respectively. The optimized conditions were determined to be a wall material concentration of 19.3%, an inlet air temperature of 171 degrees C, and a feed flow rate of 0.92L center dot h(-1). At this condition, particles presented no fissures and the compositions of pure and microencapsulated oil were similar. The sorption isotherms could be described by the GAB model.