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

Authors: DAVIDSON, JOHN - Freshwater Institute; KENNEY, P BRETT - West Virginia University; Barrows, Frederic; GOOD, CHRISTOPHER - Freshwater Institute; SUMMERFELT, STEVEN - Freshwater Institute

Submitted to: Journal of the World Aquaculture Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/12/2017
Publication Date: 8/13/2017
Citation: Davidson, J., Kenney, P., Barrows, F., Good, C., Summerfelt, S. 2017. 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. Journal of the World Aquaculture Society. 49(1):183-196. https://doi.org/10.1111/jwas.12452.
DOI: https://doi.org/10.1111/jwas.12452

Interpretive Summary: Farmed production of Atlantic salmon in recirculation aquaculture systems (RAS) and the use of alternate ingredient diets with little or no fishmeal are developing as sustainable industry trends, but have not been evaluated in combination. As fishmeal is replaced with alternate protein ingredients in aquaculture diets, fillet quality, human health benefits, and consumer acceptability of the end product could be altered. Fillet quality and processing attributes of Atlantic salmon fed a standard fishmeal diet were compared to that of salmon fed a diet without fishmeal while raising these fish in freshwater RAS. Atlantic salmon performance, fillet quality, and processing attributes were generally unaffected by diet type. Use of fisheries byproduct as lipid in the fishmeal-free diet enhanced the salmon sustainability score and maintained the human health benefits provided by omega-3 fatty acids in the fillets.

Technical 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 greater than 99%. Diet did not affect (P greater than 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.