BACKGROUND: The aquafeed sector has been replacing conventional dietary ingredients with more economic and eco-friendly ingredients. Insects embody a promising alternative as a result of being highly nutritious and showing traits leading to a circular bioeconomy. Atlantic salmon (Salmo salar L.) at the sea-water stage were fed diets with a partial or complete substitution of fishmeal with meal of Hermetia illucens larvae reared on a media containing Ascophyllum nodosum mixed with organic wastes (60:40). The present study aimed to assess the quality of fillets by characterizing its physico-chemical traits with conventional and innovative methods, such as the proton transfer reaction-time of flight-mass spectrometer technique, allowing the analysis of samples at room temperature. Finally, steamed fillets underwent a consumer test to investigate the liking of consumers and their intention of re-consumption.
RESULTS:The main findings showed that a complete dietary substitution of fishmeal with H. illucens larvae meal did not impair the physico-chemical quality of A. salmon fillets. Notably, neutral n-3 polyunsaturated fatty acids (PUFA) slightly but significantly increased in the fillets of A. salmon fed H. illucens, also as a result of the additional fish oil present in the diets containing insect. The volatile organic profile was not altered by the different diets. The consumer-liking test revealed that Italian consumers appreciated the tested salmon irrespective of the administered feed. CONCLUSION: Tailoring the insect fatty acid profile by rearing the larvae on a PUFA-rich substrate, coupled with a dietary modulation of the oily source, can successfully maintain or even increase the cardioprotective characteristics of fillets.
Physical analysesThe pH was measured in two points of the cranial and caudal regions of each fillet by a pH-meter METTLER TOLEDO (Mettler-Toledo, Schwerzenbach, Switzerland). Fillet color measurement, expressed as L* (lightness), a* (redness) and b* (yellowness) indices, 17 was performed on two points of both cranial and caudal regions, using a Konica Minolta colorimeter (Chiyoda, Tokyo, Japan). Texture measurements were performed using a Zwick Roell ) equipped with a 1-kN load cell. A 4 × 4 cm section