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.