Why food is a colloid scientists playground!

I am often told that soft matter in food is more an art than a science. It is true, we all cook … but food is far more complex than a recipe and encompasses all of the key colloidal science challenges of the past 50 years. During this presentation I will examine the complex colloidal phenomena that occur during the life of emulsions from their design, stability, degustation and digestion and outline how they are influenced by key colloidal science phenomena.
 
Starting with the creation of emulsions, a key problem is understanding and controlling the conformation of proteins at interfaces. The structure of a protein results from the fine balance of thermodynamics and kinetics leading to rich research on the “protein folding problem”. A proteins structure also governs its functionality, which is particularly the case at interfaces where adsorption to interfaces changes the energetics of the hydrophobic residues. In a series of experimental studies we examined how adsorption to oil/water interfaces changes the forces governing protein conformation and how this impact colloidal stability.¹ The conformation of a protein also impacts how it interacts with the oral surface and potentially biofilm formation. I will show some recent insights on the colloidal interactions governing mucoadhesion of emulsions and give new in vivo understanding of bio/mucoadhesion of emulsions.²
 
Understanding bio-colloidal interactions has also enabled us to create smart colloids with designed gastro-intestinal destabilisation that dramatically affects the controlled release of lipids/lipophilic active ingredients. Using MRI we were able to visualise the dynamics of gastric emulsion structuring giving us a first insight into the nature of droplet break-up in vivo.³ Fine control of surfactant assembly also allows us to create colloidal structures which can dramatically alter bioactive adsorption, which can have both positive and negative effects on health and nutrition.^{4, 5}     

Bio: Dr Tim J Wooster is a colloids and polymer scientist focusing on the biophysics of emulsions and particles. He has been working at the Nestlé Research Centre for the past 7 years, where he is the leader of the Colloidal Systems Group within the Institute of Materials Science. He obtained his PhD in materials chemistry from Monash University, and conducted post-doctoral studies at CSIRO Australia and is author of 45 journal articles (H-index 26, > 2000 citations) and ten patents.