PhD Thesis Defense by Bernat Pérez Playà, predoctoral researcher at IMB-CNM and UAB.
Supervisors:
- Dr. Manuel Castillo (UAB)
- Dra. Anna Zamora (UAB)
- Dra. Llibertat Abad (CSIC)
PhD Committee:
- Dra. Bibiana Juan (UAB)
- Dr. Jaume Esteve Tintó (CSIC)
- Dr. José Reyes de Corcuera (University of Florida)
University: Universitat Autònoma de Barcelona
PhD Degree in Food Science
About the thesis
Food dehydration is an essential technique to extend shelf life and facilitate storage and transport; however, conventional methods often involve high energy cost and can lead to the loss of functional, nutritional and sensory properties due to the application of heat. In this context, electrospraying is proposed as a sustainable alternative due to its potentially lower energy consumption and advantages, such as avoiding thermal damage during processing. 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, as well as by the functional advantages derived from the resulting microstructure. Although it has been widely studied in various fields (e.g., material science), its application in food processing has been less explored.
The objective of this thesis was to evaluate the potential application of electrospraying as a non-thermal dehydration method for liquid foods and food processing aids. To this end, two technological variants were investigated: traditional electrospraying, using laboratory-scale equipment, and a pilot-scale variant, electrospraying assisted by pressurised gas.
In conclusion, electrospraying, both in its traditional and gas-assisted forms, demonstrated the capacity to dehydrate food materials while maintaining key functional and quality attributes, yielding products comparable in several respects to those obtained through freeze-drying, with differences such as solubility or colour. Although the present study focused on the physicochemical characterization of the resulting powders, further work is required to determine the economic feasibility and practical scalability of these electrospray-based technologies. Assessing these aspects represents the next essential step for evaluating their potential integration into industrial food processing.