Dietary essential oils having natural antioxidants have been included in aquaculture feed for their potential healthy role on immune response and intestinal microbiota. Besides their use as antimicrobials, natural antioxidants added to fish feed have improved the redox balance of living fish and then promoted a higher oxidative stability of the corresponding final fishery products. Nevertheless, slaughter stress has demonstrated to affect the onset of post-mortem oxidation in cultured fish species. Hence, stress can provoke in short term the accumulation of lipid oxygenated products and reduce the commercial shelf-life, due to a higher susceptibility to develop rancidity. Accordingly, in this work we have studied the potential synergism between the incorporation of a dietary antioxidant essential oil in the feed of rainbow trout (O. mykiss) and the use of an unstressed slaughter method to enhance the oxidative stability of trout flesh. For this purpose, the effects that two different slaughter methods, asphyxia and percussion, exerted on the post-mortem quality and stability of two groups of cultured trouts (control and essential oil supplemented feed), were investigated. A comprehensive redox Lipidomic/Proteomic combined study on muscle lipids and proteins was followed in the corresponding frozen trout fillets stored for 6 months at –10ºC. The study was completed with the organoleptic evaluation of the fish flesh and the degradation of nucleotides for the assessment of stress conditions. Results demonstrated that frozen fish fillets from trout fed the antioxidant oil showed a significant protection of specific muscle proteins against oxidation and therefore, preserved muscle protein solubility and water holding capacity during frozen storage. Lipid oxidation and rancidity were also delayed in trout fed essential oils, resulting in frozen fish with higher organoleptic and sensory scores. However, stress during slaughter greatly influenced oxidative imbalance, thus promoting the earlier onset of biomarkers of instability as lipid mediators and protein carbonyls. As a consequence, fillets derived from non-stressed slaughtering method were more stable in terms of oxidative stability and showed longer shelf-life with no influence of the dietary antioxidant essential oil added to trout feed.
Stress during Slaughtering affects Oxidative Stability and Long Term Quality more than Dietary Antioxidant Supplementation in Cultured Trout / Méndez L., González M.J., Dasilva G., Secci G., Santos H.M.C., Parisi G., Medina I.. - ELETTRONICO. - (2020), pp. 24-24. (Intervento presentato al convegno 3rd International Symposium on Lipid Oxidation and Antioxidants tenutosi a web meeting nel 23 – 24 November 2020).
Stress during Slaughtering affects Oxidative Stability and Long Term Quality more than Dietary Antioxidant Supplementation in Cultured Trout
Secci G.Writing – Review & Editing
;Parisi G.Writing – Review & Editing
;
2020
Abstract
Dietary essential oils having natural antioxidants have been included in aquaculture feed for their potential healthy role on immune response and intestinal microbiota. Besides their use as antimicrobials, natural antioxidants added to fish feed have improved the redox balance of living fish and then promoted a higher oxidative stability of the corresponding final fishery products. Nevertheless, slaughter stress has demonstrated to affect the onset of post-mortem oxidation in cultured fish species. Hence, stress can provoke in short term the accumulation of lipid oxygenated products and reduce the commercial shelf-life, due to a higher susceptibility to develop rancidity. Accordingly, in this work we have studied the potential synergism between the incorporation of a dietary antioxidant essential oil in the feed of rainbow trout (O. mykiss) and the use of an unstressed slaughter method to enhance the oxidative stability of trout flesh. For this purpose, the effects that two different slaughter methods, asphyxia and percussion, exerted on the post-mortem quality and stability of two groups of cultured trouts (control and essential oil supplemented feed), were investigated. A comprehensive redox Lipidomic/Proteomic combined study on muscle lipids and proteins was followed in the corresponding frozen trout fillets stored for 6 months at –10ºC. The study was completed with the organoleptic evaluation of the fish flesh and the degradation of nucleotides for the assessment of stress conditions. Results demonstrated that frozen fish fillets from trout fed the antioxidant oil showed a significant protection of specific muscle proteins against oxidation and therefore, preserved muscle protein solubility and water holding capacity during frozen storage. Lipid oxidation and rancidity were also delayed in trout fed essential oils, resulting in frozen fish with higher organoleptic and sensory scores. However, stress during slaughter greatly influenced oxidative imbalance, thus promoting the earlier onset of biomarkers of instability as lipid mediators and protein carbonyls. As a consequence, fillets derived from non-stressed slaughtering method were more stable in terms of oxidative stability and showed longer shelf-life with no influence of the dietary antioxidant essential oil added to trout feed.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.