Processing Mixed Mesopelagic Biomass from the North-East Atlantic into Aquafeed Resources; Implication for Food Safety

Abstract

Aquaculture produces most of the world’s seafood and is a valuable food source for an increasing global population. Low trophic mesopelagic biomasses have the potential to sustainably supplement aquafeed demands for increased seafood production. The present study is a theoretical whole-chain feed and food safety assessment on ingredients from mesopelagic biomass and the resulting farmed fish fed these ingredients, based on analysis of processed mesopelagic biomass. Earlier theoretical estimations have indicated that several undesirable compounds (e.g., dioxins and metals and fluoride) would exceed the legal maximum levels for feed and food safety. Our measurements on processed mesopelagic biomasses show that only fluoride exceeds legal feed safety limits. Due to high levels of fluoride in crustaceans, their catch proportion will dictate the fluoride level in the whole biomass and can be highly variable. Processing factors are established that can be used to estimate the levels of undesirables in mesopelagic aquafeed ingredients from highly variable species biomass catches. Levels of most the studied undesirables (dioxins, PCBs, organochlorine pesticides, brominated flame retardant, metals, metalloids) were generally low compared to aquafeed ingredients based on pelagic fish. Using a feed-to-fillet aquaculture transfer model, the use of mesopelagic processed aquafeed ingredients was estimated to reduce the level of dioxins and PCBs by ~30% in farmed seafood such as Atlantic salmon.

Science governs the future of the mesopelagic zone

“…Where trade-offs between food security and climate mitigation are already being estimated for terrestrial food production 40 and in coastal sheries 41 , this has yet to be considered for the mesopelagic zone. As research into its potential contribution to and suitability for food systems moves forward [42][43][44][45][46][47] , presenting this contribution as a trade-off with climate mitigation may shut down debate about values and trade-offs before it can take place. Furthermore, as most of the mesopelagic zone is in the high seas beyond national jurisdiction, and requires expensive technology to interact with, it is likely that a small number of private or state actors will be highly in uential in these discussions.…”

Future feed resources in sustainable salmonid production: A review

“…69 The low content of persistent organic pollutants and other inorganic compounds reported suggests that oil from mesopelagic fish can be used as a sustainable and healthy alternative to conventional oils. 70 The content of LC-PUFAs, particularly DHA (22:6 n-3), is high and can help to meet the requirement for LC-PUFAs in salmon feed. A high content of monoene fatty acids, particularly oleic acid (18:1 n-9), has been reported in Myctophidae sp.…”

Assessing Dietary Exposure of Potentially Toxic Elements via Fish Consumption

“…Plants take up As from soil, productive animals -from water and feed and particularly fish flour. Seafood build up significant amounts of As, some 90-95 % of which belongs to organic As (Berntssen, et al, 2021, Pei, et al, 2019. However, there are some exceptions: hijiki algae may contain up to 60 % of inorganic As (EFSA, 2009, Camurati and Salomone, 2020).…”

“…The compounds of inorganic arsenic pose no hazard but are recognized as potentially carcinogenic. (Berntssen, et al, 2021, EFSA, 2009, Camurati and Salomone, 2020. Chronic exposure to As may cause skin lesions, neurotoxicity, anemia, diabetes, cancer (Berntssen, et al, 2021, IARC, 2004.…”