Bioengineering of β-cyclodextrin/curcuimin complex-stabilized Pickering emulsion integrated konjac glucomannan film with enhanced antibacterial properties for strawberry preservation

Epigallocatechin gallate (EGCG) and curcumin (Cur) co-encapsulated composite films were prepared using konjac glucomannan (KGM) incorporating Pickering emulsion stabilized by β-cyclodextrin (β-CD). And then the composite films were applied for strawberry preservation. The structure and properties of the films were systematically characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis, scanning electron microscopy (SEM), antibacterial property and biodegradability. The results showed that Pickering emulsion (0.2 g/L) enhanced the thermal stability, increased tensile strength to 33.17 MPa, dropped EAB from 70% to 40% with water vapor permeability of 2.5×10 -13 g·m/(m 2 ·s·Pa) and a denser structure. Both of S6 and S8 displayed high DPPH scavenging ability and strongest antibacterial effect on S. aureus and E. coli . The S8 composite film showed the inhibition zone of 16.08±2.73 mm and 19.97±0.97 mm respectively. Strawberry preservation experiments demonstrated that the film effectively delayed fruit weight loss, hardness reduction, and pH increase, thereby extending the preservation from 6 days to 8 days. Moreover, all Pickering emulsion film completely degraded in soil within 9 days, indicating good biodegradability.