Theoretical Modeling of Mechanical Behavior and Release Properties of Microcapsules

Microcapsules in food often have a shell with a complex microstructure; the mechanical and structural properties of these shells affect the response of the capsules to deforming forces and the release kinetics of encapsulated components. In this chapter we will discuss a number of models which are typically used to model the behavior of microcapsule shells, such as the 3D film model, the diffuse interface model, and the 2D sharp interface model (or Gibbs dividing surface model). For the last model we show how constitutive models for the fluxes of mass, energy, and momentum, along and across the interface, can be derived using methods from the field of non equilibrium thermodynamics; we also give examples of how these models can be used to describe the behavior of microcapsules in a flow field. Theoretical and computational methods can be an important tool in the optimization of the design of an encapsulation system