The aim of this study was to evaluate the effects of carvacrol and eugenol, separately and in combination, on survival of Listeria monocytogenes, and sensory and microbiological characteristics in vacuum packaged Oncorhynchus mykiss during refrigerated storage (4 ± 1 °C) for 20 days. The control fish fillets were analyzed for microbial (total mesophilic and psychrotrophic bacteria and lactic acid bacteria) and sensory properties. Fish fillets treated with carvacrol, eugenol, and their combination displayed populations of L. monocytogenes significantly lower, by 1.35–2.84 log cfu/g, than the control fillets during the whole storage period. No significant differences between groups of fish fillets with different active compound(s) added were noted except at the end of the storage, when the number of L. monocytogenes was significantly lower in the fish fillets with eugenol added. Sensory analysis showed that fish fillets with eugenol added were the most acceptable to trained panelists.
Taking into account the increasing need for the production of safe fish and fish products and the fact that carvacrol and eugenol, which exhibited significant antilisterial effect, are generally recognized as safe they can find its practical application in fish industry. Furthermore, as these substances are major constituents of numerous essential oils they can be considered as natural preservatives and used in the organic production as a substitute with synthetic additives which can cause adverse effects.