Optimization of bitter orange (Citrus aurantium L.) essential oil microencapsulation through spout fluidized bed drying

The bitter orange essential oils (BOOs: 10, 20, and 30%) were microencapsulated using maltodextrin (MD: 25, 50, and 75%) and whey protein concentrate (WPC: 10, 20, and 30%) through a spout fluidized bed drying technique. The encapsulation yield (EY), encapsulation efficiency (EE), loading capacity (LC), moisture content (MC), hygroscopicity (HG), bulk density (BD), tapped density (TD), particle density (PD), flowability index (FI) in terms of Carr index and Hausner ratio, porosity (PR), solubility (SO), inhibiting power, and releasing in buffer and saliva conditions were optimized using response surface methodology. The optimum point was 11.98%, 53.34%, and 23.26%, respectively, for BOOs, MD, and WPC. It was observed that a moderate concentration of core and wall materials led to the highest values of EY, EE, LC, BD, TD, PD, FI, SO, and releasing and the lowest values of MC, HG, and PR.