Popis: |
Much of our everyday nutrition is based on foods that are emulsions or have been emulsified at a certain stage during their processing. Emulsions’ inherent metastable state urges the introduction of emulsifiers, as a physical barrier that prevents droplets from coming together. In lieu of this approach, Pickering emulsions (i.e. droplets stabilised by solid particles) have amassed a great deal of both theoretical and commercial interest due to their scope of added functionalities. These include an exceptionally high stability and the compliance with the current demand for/appeal of formulations based on natural ingredients. Yet, their large scale adoption by the food industry has been hampered by the lack of a reservoir of edible structures that can be used as Pickering stabilisers. This thesis suggests the use of particles made of lipids as an alternative option for the design of Pickering-type emulsion stabilisers. Colloidal crystalline structures were fabricated via a melt-emulsification and subsequent crystallisation route. Solid particle characteristics, crucial for Pickering stabilisation (e.g. size, interfacial behaviour), could be controlled by adjustments to formulation and processing parameters. Building upon the knowledge gained from this initial study, colloidal lipid particles were assessed for their effectiveness to act as emulsifiers in oil-in-water (o/w) emulsions and also, for their aptitude to undergo a dehydration and rehydration process without variation of dimension or Pickering functionality. |