Microfluidic and membrane foaming deviced

With microfluidics (devices with very small but precisely made channels) it is possible to make droplets of exactly the same size. One of the techniques that we developed in our lab (partitioned EDGE) you can see in action in the figure. It is expected that also foams can be made very efficiently, although the mechanisms will be rather different from those in emulsion production due to the great differences in viscosity for example.

The actual bubble formation mechanism is currently investigated, and although we have achieved a lot of new insights, there is still a lot to discover. For example the geometry of the EDGE device, and the composition of the water phase are expected to influence the bubble size greatly, also as function of applied pressure. In order to understand this better, detailed investigations will be done using high speed imaging (up to 1 million frames per second) in combination with image analysis.

The insights that are thus obtained will be used to design an upscaled system. For this we will use experimental observations with model systems, and extend these insights to components that are used in practice (e.g., proteins). We have identified a new underlying mechanism that revolves around interaction between bubbles. This will help us operate this new technique efficiently, using proteins to stabilise the interfaces during preparation, and also during storage.

For up-scaling we consider various options, ranging from microfluidic systems prepared by state of the art technology and innovative approaches 3D printing. We also consider membranes that are readily available, but have a pore size distribution. We are interested to find out how membranes can be scaled up for food foam production.