Nanoencapsulated clove essential oil applied in low dose decreases stress in farmed gilthead seabream (Sparus aurata L.) during slaughter by hypothermia in ice slurry

© 2019The current procedure used to slaughter gilthead seabream involves hypothermia in seawater with crushed ice, slurry ice. This method stresses the fish and negatively affects the quality and shelf life of the fresh product. Clove essential oil (CEO), one of the most effective anesthetics when handling fish, is not used for stunning at slaughter on an industrial scale, mainly due to its very low water solubility. The main objective of this study was to evaluate the use of very low doses (5¿15 mg/kg ice) of CEO nanoencapsulated in ß-cyclodextrin (ß-CD), which is known to improve the water solubility of the essential oil, to reduce stress in farmed gilthead seabream at slaughtering. Postmortem plasmatic levels of different stress markers and the mRNA expression level of several immune- and stress-related genes were evaluated. In conclusion, CEO nanoencapsulated in ß-CD used within the ice at slaughtering significantly decreases fish stress compared to the current procedure that uses only ice.