Abstract
The growing demand for Ready-to-Eat (RTE) fish products increases the need for effective safety measures against Listeria monocytogenes, a pathogen associated with high fatality rates. This study evaluated the bioprotective potential of lactic acid bacteria (LAB) strains, including probiotic ones, against L. monocytogenes in cold-smoked rainbow trout. Two LAB cocktails were tested: a commercial mix (LC-LL) and a vegetable-derived mix (LAB2-LP15). LC-LL effectively inhibited L. monocytogenes at both static (5 °C) and dynamic (4-20 °C) conditions by the inhibitory effect of the bacteriocin leucocin (≈4 log unit growth inhibition). In contrast, LAB2-LP15 was effective only at 5 °C (≈2 log unit growth inhibition), maintaining the best sensory characteristics. These findings support the use of LAB as natural bioprotective agents in RTE fish, combining food safety and sensory preservation.