Naturally crosslinked gelatin gels with modified material properties

Natural crosslinking of gelatin using a simple plant-derived phenolic compound, caffeic acid has been studied. For the first time, we are reporting a thermo-irreversible gelatin gel formation at 60 °C. Controlling the crosslinking reaction has resulted in obtaining gelatin with modified material properties. Reaction parameters such as reaction pH, reaction time and concentration of caffeic acid have been optimised to obtain different degrees of crosslinking. The modified material properties were studied using small and large deformation rheology. Gelatin crosslinked at 60 °C and pH 9 for 20 min using 1.5% concentration of caffeic acid showed higher melting and setting temperatures. The storage modulus and gel strength were also found to be higher for crosslinked gelatin at higher temperatures.