Pectin/tamarind gum-based edible active films reinforced with supramolecularly self-assembled apigenin nanocrystals for shelf-life extension of strawberries.

Apigenin nanocrystals (AN) were synthesized through supramolecular self-assembly and incorporated into a pectin/tamarind gum (PTG) matrix to fabricate edible bio-based nanocomposite films. Scanning electron microscopy (SEM) confirmed that AN exhibits a rod-like nanostructure. Both simulations and experimental results demonstrated that supramolecular interactions are the primary driving force behind AN self-assembly. The nanocrystals showed excellent biocompatibility. Structural characterization revealed that AN was uniformly dispersed within the PTG matrix. It formed strong intermolecular interactions and a dense three-dimensional network. As a nanofiller, AN significantly enhanced the mechanical properties of the films. The tensile strength (TS) reached 9.89 MPa, and the elongation at break (EAB) reached 56.83%. These values outperform those of films containing non-self-assembled Apigenin (Ap) (TS = 8.52 MPa; EAB = 51.61%). In addition, AN improved the thermal stability, UV-blocking ability, and water vapor barrier properties of the PTG films. Its higher specific surface area also provided superior antioxidant and antibacterial activities compared with untreated Ap. In strawberry preservation tests, PTG films containing AN extended the shelf life to eight days.