Fabrication and characterisation of electrospun zein-based fibres functionalised by caffeic and p-coumaric acid for potential active packaging applications

This study focused on the fabrication of zein-based coatings functionalised by two phenolic acids, caffeic acid (CA) and p-coumaric acid (pCA), using electrospinning. The electrospun fibres were fabricated with three different concentrations (5%, 10% and 20% w/w) of CA and pCA individually. The average fibre diameter (AFD) increased due to the addition of phenolic acids. Thermogravimetric analysis (TGA) revealed that degradation temperatures of the zein electrospun fibres were not significantly affected (P > 0.05) after the incorporation of CA and pCA. Meanwhile, interactions between zein and the phenolic acids were indicated by surface characterisation. CA-loaded zein electrospun fibres exhibited increasing antioxidant activity with increasing CA concentration. Both phenolic acid-loaded zein electrospun fibres displayed favourable antibacterial activities against S. aureus and E. coli foodborne pathogens. Overall, zein electrospun fibres with 20% w/w CA demonstrated the most desirable properties for potential active food packaging application.