Effect of the dietary supplementation based on essential oils on the quality of gilthead seabream

Abstract

The effectiveness of using essential oils against fish parasites and pathogenic bacteria as environmentally friendly phytotherapeutic agents in the aquaculture industry is demonstrated. A commercial additive composed of garlic essential oil, thymol and carvacrol (AROTEC-G®) was added to a diet for gilthead seabream (Sparus aurata) as a protection strategy against Sparicotyle chrysophrii. The intense aromatic properties of these essential oils might lead to the need of a suppression time to reverse possible changes in the organoleptic quality of the fish. Two experimental groups were set up: an experimental group fed a commercial feed supplemented with AROTEC-G® (diet A) during the first 4 weeks of the nutritional assay, and after which the treatment was suspended for 14, 21 and 28 days after a first sampling performed (day 0); and a control group, fed the same basal diet without AROTEC-G® supplementation (diet C). A physicochemical evaluation measured the pH, colour and texture, and a descriptive quantitative sensory analysis (QDA) was carried out using a trained panel for gilthead seabream fillets. Overall, the findings showed that the use of dietary essential oils did not result in significant sensory differences after day 0 of the study, although slight differences were observed in some of the physicochemical parameters analysed.