Development of Gelatin-Based Active Packaging and Its Application in Bread Preservation

Abstract

The issue of plastic pollution has attracted widespread social attention. Gelatin is valued as a degradable bio-based material, especially as an edible active packaging material. However, the commonly used solution-casting film-forming technology limits the mass production of gelatin films. In order to improve the production efficiency and enhance the commercial value of gelatin films, in this study, fish gelatin (FG) particles were successfully blended with essential oils (EOs) to prepare active films by melt extrusion technique, a common method for commercial plastics, and applied to bread preservation. FG and EOs showed good compatibility with each other. The elongation at break was enhanced in all samples of films containing EOs. The addition of EOs weakened the oxygen barrier properties of the FG films. The gelatin films containing clove EO showed the highest DPPH radical scavenging rate of 39.38%. The films containing oregano EO showed the highest antibacterial activity, with 98.84% and 99.86% against S. aureus and E. coli, respectively. The bread preservation results showed a slower microbial growth rate in the samples preserved by the active films. The bread samples preserved in commercial PE film showed mold on day 3, and the bread samples preserved in active gelatin film showed mold visible to the naked eye by day 7. This study demonstrates the potential of gelatin-based activated films for commercial application in baked goods preservation.