Transglutaminase effect on the gelatin-films properties

The development of biodegradable materials, especially those from renewable sources, is important to reduce the impact of plastic waste on the environment. On the other hand, protein-based films have high solubility in water, in addition to limited mechanical properties, which makes their application in high humidity environments a challenge. The enzyme transglutaminase (TGase) can reduce the interaction of gelatin films with water, improving these properties, while improving the mechanical properties. Therefore, this study aimed to determine the best condition for using the TGase enzyme, through variations in the gelatin and enzyme mass, in addition to the time that the enzyme acts on the gelatin, evaluating the properties tensile strength, elongation, and solubility in water. In the second set of experiments, gelatin amount was kept fixed at 4%, and other proportions of an enzyme (1% and 5% w/w gelatin) were studied, evaluating beyond these properties the degradation in simulated soil through thermogravimetry analysis and Fourier transform infrared spectrometer (FTIR). It was concluded that the higher concentration of TGase (5%) promoted a greater reduction in the solubility of the films, making the films more resistant to biodegradation, facilitating their application due to the increase in their useful life. At the end of the degradation test, it was noticed that the films were degraded, presenting the potential for substitution of polymers of fossil origin, which could be an alternative to the problem of polymeric residues in the environment.