Characterization of Microencapsulated Thymus schimperi Essential Oil Prepared by Spray and Freeze-Drying Using Gum Arabic as Carrier Material

The process of microencapsulation is used to coat essential oils that are vulnerable to oxidation, dampness, UV light, and high temperatures. It serves to shield the active chemicals from the environment while boosting the core material's controlled release, stability, and solubility. This work used spray and freeze-drying procedures to microencapsulate essential oil extracted from Thymus schimperi (T. schimperi) leaves using hydro distillation. The objective of this study was to investigate the impact of gum Arabic as a coating agent on the physicochemical properties of T. schimperi essential oil microcapsules through spray and freeze-drying encapsulation procedures. Water content, surface morphology, solubility, bulk density, tapped density, surface oil, flowability, particle mean diameter, and other physical and chemical properties were examined. The physico-chemical properties of the microencapsulated samples were examined, including their releasing property, functional group identification, thermal property, and storage stability. The features of microcapsules made by spray drying differ greatly from those made by freeze drying. According to the results, spray drying was shown to have a higher encapsulation efficiency (71.05%) than freeze drying (68.89%). The solubility index of spray-dried microcapsules was higher than that of freeze-dried microcapsules. When compared to freeze-dried encapsulated T. schimperi EO, the bulk density of spray-dried encapsulated EO is lower, whereas the tapped density is reversed. Compared to freeze-dried microcapsules, spray-dried microcapsules had a more spherical shape.