Effect of dietary replacement of fish meal by prepupae meal of black soldier fly (Hermetia illucens) on fillet quality traits and shelf-life of EUROPEAN sea bass (Dicentrarchus labrax) juveniles

The aim of this trial was to evaluate the effects of dietary replacement of fish meal by Hermetia illucens prepupae meal (HM) in diets for European sea bass juveniles on fillet quality traits. Four diets were formulated: a control diet with fish meal as the main protein source and three experimental diets with increasing levels of HM (7.5, 15, 22.5% of the total dietary protein) replacing fish meal, which were fed fish over a period of 62 days. At the end of the trial, sea bass fillets were sampled for analyzing the physical (colour and pH) and chemical quality traits (fatty acid profile, lipid nutritional indexes and lipid oxidation products) during the shelf life, at two different times, T0 (corresponding to the initial time) and T3 (corresponding to three days of storage in a fridge, at a temperature of +2 ºC). Irrespectively the dietary fish meal replacement level, HM incorporation lead to no significant differences in colour of muscle, skin and liver, in pH, proximal composition during shelf life and in liver fatty acid profile. On the other hand, dietary inclusion of 22.5% of HM decreased lipid oxidation in muscle, as showed by the significant decrease of TBARS values, due to the difference in fatty acid profile. In conclusion, the dietary replacement of fish meal by HM, up to 22.5% of the diet, did not affect the fillet quality traits and shelf-life of European sea bass, and may inclusively reduce lipid oxidation.