Fillet Quality and Processing Attributes of Postsmolt Atlantic Salmon, Salmo salar, Fed a Fishmeal-free Diet and a Fishmeal-based Diet in Recirculation Aquaculture Systems

Abstract

Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS). To this end, a study was conducted comparing fillet quality and processing attributes of postsmolt Atlantic salmon fed a fishmeal-free diet (FMF) versus a standard fishmeal-based diet, in replicate RAS. Mean weight of Atlantic salmon fed both diets was 1.72 kg following the 6-mo trial and survival was >99%. Diet did not affect (P > 0.05) processing and fillet yields, whole-body proximate composition(fat, moisture, protein), fillet proximate composition, cook yield, fillet texture, color, or omega-3 fatty acid fillet content, including eicosapentaenoic acid and docosahexaenoic acid levels. Whole-body ash content was greater in salmon fed the FMF diet. The FMF diet resulted in a wild fish-in to farmed fish-out ratio of 0:1 per Monterey Bay Aquarium's Seafood Watch criteria due to its fishmeal-free status and use of lipids from fishery byproduct. Overall, fillet quality and processing attributes were generally unaffected when feeding a diet devoid of fishmeal to postsmolt Atlantic salmon cultured in RAS. [Correction added on 7 September 2017, after first online publication: the P value in Abstract has been changed from “P < 0.05” to “P > 0.05”.].