Crosslinked starch/konjac glucomannan active films containing encapsulated thymol for cherry tomatoes preservation

Abstract

Active films attracted growing interest due to environmental protection and safety of food packaging materials. In this study, we developed cross-linking corn starch/konjac glucomannan active films by incorporating thymol microcapsules (TMs). FTIR, XRD and SEM results indicated the formation of molecular interactions and good compatibility between cross-linking matrixes and TMs. The cross-linking effect with citric acid (CA) significantly reduced the water vapor permeability and swelling rate of the films. Addition of TMs in the composite films improved mechanical property, moisture content, light barrier property and antibacterial activities against E. coli and S. aureus. Additionally, the MCSK4 films effectively reduced weight loss, maintained firmness, and enhanced total phenolic content and total flavonoid content of cherry tomatoes. The synergistic effects of CA and TMs improved the structural and functional properties of composite films, providing a potential application for fruit and vegetable preservation.