Dual Antimicrobial–Antioxidant Postbiotics From Lactiplantibacillus plantarum for Clean‐Label Meat Preservation

ABSTRACT The rising consumer demand for clean‐label foods has intensified the search for natural alternatives to synthetic preservatives. Postbiotics from lactic acid bacteria are safe and multifunctional, but their effectiveness in real food systems remains unclear. This study examined the biochemical composition, functional properties, and biopreservation potential of cell‐free supernatants (CFSs) produced by two Lactiplantibacillus plantarum strains (MI131 and MI207). Compositional analyses by FTIR, GC–MS, and UHPLC identified diverse bioactive metabolites. GC–MS detected 25 metabolites, with MI131 being more abundant. UHPLC confirmed the presence of phenolic acids and flavonoids, which are known for their antioxidant activity. Antioxidant activity, measured by DPPH assay, was similar for both strains. Antibacterial tests showed strain‐specific effects: MI131 exhibited a broader inhibition spectrum, whereas MI207 had lower minimum bactericidal concentrations against Listeria monocytogenes and Salmonella Typhimurium (6.25 mg/mL). Applying CFS to meat stored for 15 days at 4°C reduced viable counts (< 3 log CFU/g) and inhibited pathogens, as confirmed by culture‐based methods and qPCR. The results support the use of postbiotics from L. plantarum strains MI131 and MI207 as natural biopreservatives that extend shelf life, promote clean‐label formulations, enhance safety, and reduce reliance on synthetic antimicrobials, thereby aligning with EU regulations.