(583e) Characterization of Adsorption of Food Proteins at Oil-Water Interfaces of Monodisperse Emulsions

Dairy proteins play an essential role as emulsifiers in various food applications. Understanding their adsorption behavior at oil-water interface is crucial for elucidating the mechanisms underlying emulsion formation as well as their long-term emulsion stability. In this study, we developed a microfluidics-based approach to characterize the adsorption of dairy proteins onto monodisperse emulsion interfaces at timescales of minutes to many hours. In general, we find that the adsorption curve shows an increase in interfacial load with time, followed by a saturated load. We characterize this interfacial adsorption kinetics as a function of bulk protein concentration and protein type. We find that irrespective of the bulk concentrations, flexible proteins exhibited higher adsorption efficiency compared to globular proteins. Mapping the saturation load as a function of bulk concentration, we determine the monolayer coverage for the different proteins. Interestingly, we find that at higher bulk concentrations, the saturated load exceeds the monolayer coverage indicating the formation of multi-layered protein films or protein aggregates. In summary, our work describes a novel method to characterize the interfacial load of proteins at oil-water interfaces