A novel starch-based film integrated with Nisin-A and curcumin nanoemulsion for real-time monitoring of salmon freshness

Freshness deterioration of salmon during cold storage poses significant safety concerns, highlighting the need for real-time monitoring strategies. Herein, a novel starch-pectin film incorporating Nisin-A and curcumin nano-emulsion (SP-NC film) was developed for real-time monitoring of salmon freshness. FTIR, XRD, and molecular dynamics simulations confirmed strong molecular compatibility and stable hydrogen bonding among film components. The SP-NC film exhibited high mechanical strength, with a tensile strength of 4.51 MPa and elongation at break of 43.58 %, as well as outstanding barrier properties reflected by low water vapor permeability (6.82 × 10 −10  g·mm −1 ·s −1 ·Pa −1 ) and oxygen permeability (6.10 × 10 −9  g·mm·mm −2 ·s −1 ). Under blue light, the SP-NC film reduced S. aureus and Salmonella survival rates to 1.85 % and 3.79 %, respectively. When applied to 4 °C refrigerated salmon, the SP-NC film extended shelf life from 4 to 8 days and provided visual spoilage indication. Overall, this study offers a valuable reference for the design of intelligent food packaging.