PhD defence

Muhammad Khan: Electrospraying for efficient coating of foods

2e promotor: prof. dr ir RM Boom

There is a continuous need for thinner edible coatings with excellent barrier properties, and this requires new application methods. Electrospraying is known to yield fine droplets of size down to 20 μm, giving the potential of very thin and even coatings. The droplets size was influenced by flow rate, conductivity, nozzle height and electrostatic potential. Deposition of these charged droplet was influenced by amount of water (related with conductivity) present in the food surface. The conductive surfaces received more material and early film formation compared to insulator surfaces (parafilm). The droplet deposition was random irrespective of the target surface conductivity. However, have different mode of film formation on different surfaces.

Electrospraying reduced the amount of coating material by coating the top as well as sides of 3D object without much influence the final barrier properties. Besides coating, this method can also be used to make meat fibres and encapsulation of active ingredients.