Emerging Biocontrol Strategies in Cheese Safety: A Critical Review of Bacteriophages, Antimicrobial Peptides, and Postbiotics

Fresh and soft cheeses feature high moisture content, elevated water activity, and nutrient richness, creating favorable conditions for foodborne pathogens including Listeria monocytogenes, Salmonella spp., Shiga toxin-producing Escherichia coli, and Staphylococcus aureus, which can contaminate products via post-pasteurization biofilm formation on processing equipment. Because conventional thermal and chemical preservation methods can compromise organoleptic and nutritional quality, biological control strategies have emerged as promising alternatives to enhance microbiological safety. This review critically evaluates three biopreservation modalities along their technological maturity gradient: bacteriophages and endolysins, antimicrobial peptides (AMPs) and bacteriocins, and postbiotics. Bacteriophages present high operational readiness, supported by regulatorily cleared commercial preparations; however, their lytic activity is frequently constrained by low temperatures, acidic pH, and matrix-bound fat. AMPs and bacteriocins—anchored by nisin—are extensively researched, with contemporary innovation focusing on advanced delivery vehicles, including active packaging, nanoencapsulation, and in situ bacteriocinogenic starter cultures, to preserve peptide stability throughout ripening. Postbiotics—here referring specifically to preparations consistent with the International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus definition of inanimate microorganisms and/or their components, as distinct from the cell-free supernatants and fermentates most often tested in cheese—offer good physicochemical stability and dose control, albeit with lower and more variable intrinsic antimicrobial potency. Across all modalities, multi-target hurdle approaches consistently outperform single-agent applications, with surface-targeted delivery representing the dominant engineering strategy. Persistent limitations across all strategies include post-treatment bacterial regrowth, matrix interference, non-standardized activity units, and unresolved regulatory status. Moving forward, standardized, full-shelf-life challenge trials in real cheese matrices under harmonized storage conditions are imperative to benchmark these biointerventions head-to-head against conventional methods and live protective cultures.