Tuning the properties of gelatin films through crosslinking and addition of ionic liquids

The exploration into biopolymer applications has experienced fast growth in recent years due to the ever-growing environmental and societal demand for a greener and safer environment. In this study, fish gelatin-based films with fructose and different choline-based ionic liquids, such as choline dihydrogen phosphate, choline acetate, and choline serinate, were prepared to assess the effect of Maillard reaction and the inluence of the ionic liquids on the film properties. Overall, the presence of physical and chemical interactions enhanced UV–Vis light absorption capacity, reduced the solubility, improved film flexibility and conductivity. These changes were related to the formation of Maillard reaction products, the plasticising effect of ionic liquids and the increase in ionic mobile species associated with the ionic liquids within the films. This study shows the possibility of tailoring the properties of bio-based materials via Maillard reaction and the addition of ionic liquids. • Gelatin film properties were tailored through Maillard reaction with fructose. • The incorporation of ionic liquids enhanced the film flexibility and conductivity. • Resulting films were non-toxic and showed antimicrobial activity.