Preparation of postbiotic-electrospinning antimicrobial film and its preservative effect on taihe silkies

• A strain of Lactobacillus plantarum with significant antimicrobial activity against was selected. • A gelatin/chitosan-based nanofibrous film incorporated with 15% postbiotics was successfully fabricated via electrospinning, exhibiting enhanced thermal stability, hydrophilicity, and antimicrobial activity. • The developed postbiotic-loaded film effectively inhibited microbial growth, delayed protein and lipid oxidation, and extended the shelf-life of Taihe Silkies chicken by 4 days during storage at 4°C. The rising consumption of Silkie chicken has underscored the challenge of its short shelf life, which results from the predominant distribution in chilled, bulk form. This study aims to screen lactic acid bacteria-derived postbiotics with antimicrobial activity and to fabricate postbiotics-loaded gelatin-chitosan composite films with enhanced antimicrobial properties via electrospinning technology for retarding the spoilage of Silkie chicken. The postbiotics derived from Lactobacillus plantarum ZJUIDS18 (GQ1501) exhibited significant antibacterial activity against five common spoilage bacteria ( Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 9027, Salmonella enterica serovar Typhimurium ATCC 14028, and Listeria monocytogenes CMCC 54007), with inhibition zone diameters of 2.00 ± 0.50 mm against P. aeruginosa and 1.17 ± 0.09 mm against Listeria. A comprehensive evaluation of the physicochemical and preservative properties of the composite films was conducted. The results demonstrated that increasing the postbiotics content led to notable improvements in film performance. Specifically, the film incorporating 15% postbiotics showed a maximum decomposition temperature of 323.9 °C, a water contact angle of 51.8°, a tensile strength of 1.12 MPa, and an elongation at break of 3.69%. Application of the 15% postbiotics film on Silkie chicken during 10-day storage at 4 °C significantly reduced the total viable count by 2.59 log CFU/g and decreased the total volatile basic nitrogen (TVB-N) content by 18.70 mg/100 g compared to the control. Furthermore, it effectively delayed lipid and protein oxidation, thereby extending the shelf life of Silkie chicken by 4 days. These findings confirm the promising potential of the developed postbiotics-loaded film for application in active food packaging.