Models for the mechanical characterization of core-shell microcapsules under uniaxial deformation

In this research, we characterized edible, polymer-based microcapsules composed of a sunflower oil core and a gellan gum shell. We measured the force-displacement relationship of the microcapsules under uniaxial compression with a cantilevered-capillary force apparatus (CCFA). The analysis reveals the critical importance of determining the precise point of compressive contact. Two models are presented for describing the data, one from the literature and one presented here for the first time. We conclude that both models may be useful depending on the type of microcapsule and show that our new model has the advantage of producing an overall modulus for the capsule in addition to the modulus of shell material.

Automated summary

This research characterized polymer-based microcapsules with a sunflower oil core and a gellan gum shell. Analysis of the force-displacement relationship under uniaxial compression emphasized the importance of determining the precise compressive contact point. Two models were presented to describe the data, with the new model showing the advantage of providing an overall modulus for the capsule as well as the modulus of shell material.