Novel bio-based active packaging film with colloidosome-encapsulated clove essential oil

To mitigate the thermal instability of essential oils, we engineered robust colloidosomes via the cross-linking of soy protein isolate nanoparticles (SPI NPs) using poly(hexamethylene diisocyanate) (PHDI) to encapsulate clove essential oil (CEO). Subsequent to a systematic screening of filler loadings, these colloidosomes were incorporated into a gelatin-κ-carrageenan (GK) matrix. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) confirmed that PHDI initiated nucleophilic addition, constructing a rigid shell while facilitating secondary interfacial grafting. This covalent interlocking ensured uniform dispersion and eliminated phase separation defects. In particular, the 40 wt% PHDI treatment yielded complete shell integrity, effectively shielding the CEO from thermal degradation. Accordingly, the optimized GK-CE-40 film featured a densified network structure, translating to superior UV/water vapor barrier properties, high tensile strength (13.41 ± 1.56 MPa), and sustained antioxidant/antibacterial activity (51.28% DPPH scavenging; 20 mm inhibition against E. coli ). Preservation trials on cherry tomatoes demonstrated significant retention of firmness and appearance over 10 days. These results validate interfacial cross-linking as a potent strategy to resolve the stability-dispersibility trade-off in bio-based packaging.