Proof of concept of electrospraying skimmed milk

Electrospraying is a process that uses an electric field to remove solvents from polymeric solutions, allowing the production of micro- and nanoscale particles. This technique is characterized by its non-thermal nature, which avoids thermal damage to treated materials. This method has not been employed as a dehydration approach in food processing, and its potential applications in this field have not yet been explored or studied in depth. In this study, electrospraying for the removal of water from reconstituted milk was evaluated, yielding promising results. The increase in the distance between the tip and the collector did not show significant effects on the size of the drops due to the interaction of two opposite effects: the decrease in the intensity of the electric field and the increase in the residence time. It was also observed that a larger diameter of the tip resulted in big drops, while a high fat content generated small drops due to the increase in viscosity and decrease in surface tension. The diameter of the droplets was reduced by decreasing the flow rate and/or increasing the concentration of total solids. Finally, electrospraying, at a low flow rate, eliminated water significantly ( p < 0.05) without producing any significant effect on the structure of proteins (i.e., caseins and whey proteins). These findings open the way for novel research directions in the drying of high–value liquid foods, highlighting the potential of this technique for innovative applications within the food processing sector.