Preparation of vanillin nanoparticle/polyvinyl alcohol/chitosan film and its application in preservation of large yellow croaker.

The novel polyvinyl alcohol/chitosan films incorporated with vanillin/zein/κ-carrageenan nanoparticles (VZCNPs) were developed. The polyvinyl alcohol/chitosan/vanillin nanoparticles (PVA/CS/NPs) films had exhibited enhanced tensile strength, hydrophobicity, antioxidant activities and antimicrobial efficacy, all of which varied with the different concentrations of VZCNPs. Notably, the PVA/CS/NPs-10 film exhibited exceptional performance, with a reduced Moisture Content of 15.68 ± 0.46 %, an increased water contact angle of 65.75°, and improved ABTS scavenging rate of 77.39 ± 0.54 %, demonstrating outstanding antioxidant activity and antimicrobial properties. The PVA/CS/NPs films were further applied to the packaging of large yellow croaker (Pseudosciaena crocea) to evaluate their preservation capability at 4 °C. The results indicated that the PVA/CS/NPs films effectively inhibited microbial growth and lipid oxidation, thereby delaying the spoilage of large yellow croaker. High-throughput sequencing study showed that the films effectively inhibited spoilage bacteria, including Comamonas, Pseudomonas, and, Burkholderia and affected the distribution of bacterial populations during storage. This study provides new insights into prolonging the shelf life of fresh-frozen large yellow croaker and developing advanced preservation methods for the future development of the aquatic product.