Mathematical models of controlled drug release applied to an encapsulation system of food active compounds

The release of an encapsulated food active compound (model case: astaxanthin encapsulated in alginate matrix) was described by simple mathematical models from the pharmaceutical field. The models considered dissolution, diffusion, erosion, or swelling. The errors ranged from 17.6% to 49.2%. The active diffusion coefficient was in the order of 10−12 m2/s. The model case required considering dissolution, erosion, and matrix changes (due to water uptake). The proposed models and determined parameters can be considered as basic tools to simplify the analysis and identification of the phenomena governing the release of food active compounds for a wide range of scenarios.