Mathematical modeling of the red ginger oleoresin release from chitosan-based microcapsules using emulsion crosslinking method

Abstract

The mathematical model was developed analytically to describe the release of red ginger oleoresin (Zingiber officinale var. rubrum) from microcapsules prepared by cross-linking emulsion method with chitosan as wall material. The model of release used a reservoir system, where red ginger oleoresin diffused through the chitosan membrane (wall material) to the solution medium. The assumption was that the microcapsule diameter was much larger than the wall thickness; therefore the mathematical equation was approximated by diffusion through the slab. Comparison between experimental data and calculated data of red ginger oleoresin concentration in buffer solution (CAw) was used to verify the suitability of the mathematical model. Mathematical models for controlled release was in good agreement with experimental data which was indicated by the value of R2 = 0.76–0.86. Keywords: Chitosan, Diffusion coefficient, Red ginger oleoresin, Emulsion crosslinking, Reservoir system