Improvement of Techno-Functional Characteristics of Fish Gelatin Films Using Peptide-Sugar Conjugates: Maillard Reaction Products

The effects of Maillard Reaction Products (MRPs) obtained from fish gelatin hydrolysates and D-glucose conjugation on the techno-functional characteristics of fish gelatin films were investigated, and the antioxidant effects were measured. MRPs were added to a gelatin solution at different concentrations (5-30% of the gelatin weight). The results revealed that the addition of the MRPs changed the film thickness from 0.15 mm (control) to 0.199 mm (film containing 30% MRPs). Some parameters including density, opacity, and color (ΔE) of the films were directly related to the MRPs concentration. Unlike these parameters, the solubility of the samples was not significantly altered, and the degree of swelling was indirectly changed owing to the MRPs addition. The results also indicated that the MRPs could dramatically decrease the water vapor permeability and oxygen permeability. The viscosity and mechanical properties of the films were increased as the MRPs concentration increased. The UV protective and the DPPH radical scavenging activities of the films were positively related to the MRPs concentration. The control sample (8.71 mg/mL) and the sample containing 30% MRPs (IC50 at 1.72 mg/mL) showed the lowest and highest antioxidant activities, respectively. The results of this study revealed that a fish gelatin film containing MRPs could be used as an active film in food packaging.