Microfluidics can be used to produce emulsions but also to study the stability of emulsion droplets during production and further processing . In this project we focus on the use of microfluidic tools to study emulsifier adsorption and emulsion stability. Measurements are done with a microfluidic Y-junction and coalescence channel. Results are related to industrial processing conditions in order to gain understanding of emulsification at relevant time and length scales.
Based on previous work in our group  we developed a microfluidic method to measure interfacial tension in time scales relevant for industrial emulsification (i.e., sub-milliseconds to milliseconds) . The method is based on the relation between droplet size and the continuous phase velocity and viscosity, dispersed phase flow rate and the interfacial tension between the two fluids at the moment of detachment. Accurate measurements are possible because of the high monodispersity of the formed droplets and advanced image analysis (Clip 1). Figure 1 illustrates typical results found with this method, for example with sodium dodecyl sulphate (SDS) used as a model emulsifier. Our next steps are to gain better understanding of emulsifier transport mechanisms in the microfluidic device, and to apply this method to study the adsorption of food-grade emulsifiers.
This work is supported by NanoNextNL, a micro and nanotechnology consortium of the Government of the Netherlands and 130 partners.
Cross-flow microfluidic emulsification from a food perspective
Dynamic Interfacial Tension Measurements with Microfluidic Y-Junctions
Interfacial tension measured at high expansion rates and within milliseconds using microfluidics
Coalescence dynamics of surfactant-stabilized emulsions studied with microfluidics
How microfluidic methods can lead to better emulsion products