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Effective biopreservation measures are needed to control the growth of postprocess <i>Listeria monocytogenes</i> contamination in fresh whey cheeses stored under refrigeration. This study assessed growth and biocontrol of inoculated (3 log₁₀ CFU/g) <i>L. monocytogenes</i> in vacuum-packed, fresh (1-day-old) or ‘aged’ (15-day-old) Anthotyros whey cheeses, without or with 5% of a crude enterocin A-B-P extract (CEntE), during storage at 4 °C. Regardless of CEntE addition, the pathogen increased by an average of 2.0 log₁₀ CFU/g in fresh cheeses on day 15. Gram-negative spoilage bacteria also increased by an average of 2.5 log₁₀ CFU/g. However, from day 15 to the sell-by date (days 35–40), <i>L. monocytogenes</i> growth ceased, and progressively, the populations of the pathogen declined in most cheeses. This was due to an unmonitored, batch-dependent natural acidification by spoilage lactic acid bacteria, predominantly <i>Leuconostoc mesenteroides</i>, which reduced the cheese pH to 5.5, and finally to ≤5.0. The pH reductions and associated declines in pathogen viability were greater in the CEntE-treated samples within each batch. <i>L. monocytogenes</i> failed to grow in cheeses previously ‘aged’ in retail for 15 days. Overall, high population levels (>7.5 log₁₀ CFU/g) of psychrotrophic <i>Enterobacteriaceae</i>, particularly <i>Hafnia alvei</i>, were associated with an extended growth and increased survival of <i>L. monocytogenes</i> during storage.