Functionalized gellan gum hydrogel encapsulating emulsion of probiotic/sea buckthorn oil and co-loading protocatechuic acid for chicken meat preservation.

Food packaging can effectively reduce food deterioration caused by microbial contamination and adverse storage conditions. In this study, Lactobacillus paracasei Jlus 660321 (LP) was incorporated into a sea buckthorn oil (SBO)-based emulsion and subsequently combined with protocatechuic acid (PCA) in a low-acetyl gellan gum (GG) matrix to construct a multifunctional hydrogel (GPX). GPX showed enhanced mechanical properties and high ABTS and DPPH radical-scavenging activities (>80%). Cell-free supernatants from hydrogels containing LP exhibited high antibacterial activity against E. coli, S. aureus, and S. enteritidis, and the emulsion-hydrogel matrix was available for maintaining LP viability. Water dissolution observations, zebrafish embryo assays, cell viability tests, hemolysis analysis, and compatibility with Lactobacillus rhamnosus provided preliminary evidence of GPX biocompatibility. For chicken meat preservation, GPX treatment reduced the total viable count to 6.22 log CFU/g compared with that of control (7.24 log CFU/g), and showed low TVB-N by 23.30% at 4 °C on day 7. Therefore, this study explored potential application of multifunctional hydrogels for food preservation.