Encapsulation of cinnamon leaf oil within chitosan: formulation and characterization

Abstract

Chitosan microcapsules containing cinnamon leaf oil were formed by ionotropic gelation of chitosan by crosslinking with sodium tripolyphosphate. The microencapsulation method for oil loading was optimized by varying the amounts of polymer, oil and cross linker. The effect of varying process parameters on the encapsulation efficience (EE), oil loading capacity (LC) and release rate was monitored. The formulated microcapsules were characterized using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). SEM imaged clear spherical shaped oil loaded microcapsules with a crimpy surface while empty capsules had a smooth texture.FTIR spectra evidence for the successful encapsulation of oil within wall material. EE increased with increasing oil load while it decreased with increasing polymer and cross linker concentration. LC increased with increasing amounts of oil and crosslinker and showed a decrease with increasing polymer amounts. Release rate of oil increased with increasing oil loading whereas it decreased with increasing polymer and crosslinker amounts. Varying the process parameters has a direct impact on the EE, LC and release rate. The optimum formulation for cinnamon oil microcapsules is polymer, 1 g : oil, 3g: cross linker, 0.5 g with an EE of 91%, and a LC of 38%.

Keywords

• encapsulation, cinnamon oil, essential oil, chitosan, microcapsules