Neglected fish, #poorimabuoni, garner full marks from the Istituto Superiore di Sanità (ISS) in a study examining their nutritional values and food safety. (1)
The consumption of oily fish-and particularly those lesser-known but equally valuable species-is therefore an excellent opportunity to provide valuable nutrients and micronutrients for health.
The EU research project SEAFOODTOMORROW, in which ISS is participating, has thus enabled the development of ready-to-eat foods with appreciable nutritional and organoleptic profiles from underutilized fish species.
Fish, human nutrition and health
Fish, crustaceans and shellfish are sources of high biological value protein, marine Omega-3 fatty acids (EPA+DHA) and essential micronutrients (vitamins and minerals). (2) However, depopulation of fish stocks calls for more attention to the sustainability of supplies. Andaquaculture, today better than fishing, is proving capable of ensuring a suitable response to global demand. (3)
At least two weekly servings of fish are recommended to ensure that each person has the minimum coverage of requirements for omega-3 fatty acids, vitamin D, and trace elements such as selenium and iodine (in marine species). More frequent consumption, 3-4 servings weekly, is recommended to reduce the risk of cardiovascular disease in adults, as well as for pregnant women to promote better brain development in the unborn. (4)
Fish and heavy metals? The benefits outweigh the risks
The presence of heavy metals (e.g., methylmercury) in fish is possible, depending on the pollution levels in the watersheds–related to the concentration of industries near the coast–and the duration of environmental exposure, which is longer in larger, long-lived fish.
However, risk-benefit analysis indicates how the health benefits associated with the consumption of seafood far outweigh, in most cases, the possible contraindications related to the presence of heavy metals. The content of which in fish is in any case subject to legal limits and official controls. (5)
#SEAFOODTOMORROW, the European research project.
The European research project SEAFOODTOMORROW, in the Horizon 2020 program, has the dual objectives of:
– Promote sustainable aquaculture, focusing on fish species of particular nutritional value,
– Develop innovative processing processes aimed at making foods of high sensory and nutritional quality even from neglected fish. (6)
European research in this area, as well as in microalgae (ProFuture), aspires to ensure greater availability of high-quality protein from sustainable sources.
Neglected fishes, #poormabobs. Nutritional characterization
Three underutilized species (‘neglected fish’) – blue whiting, brown pout and dab – have been used, along with carp and blue mussels, to make semi-industrial ready-to-eat products that are palatable, tasty, safe, nutritious and affordable. Having regard to children (8-10 years old), pregnant women (20-40 years old) and the elderly (> 60 years old), as well as nutritional and consumption requirements (e.g., chewability, absence of spines) (7)
All species showed important trace element values including selenium, especially in brown busbana, and iodine, as well as iron, copper, and zinc. The bioavailability of iodine was very satisfactory, 98%, reflecting the excellent nutritional quality of these foods.
Toxicological analysis
Mercury was found to be present, in the form of methylmercury, in all species analyzed. Especially in brown pout(Trisopterus luscus, also known as brown cod or French cod), which feeds on the seabed. Cadmium, nickel and lead were found to be very low, 1-2 degrees higher in mussels. However, the concentrations were found to be below tolerance limits, with the exception of mussels, which should therefore be consumed with caution by sensitive individuals (e.g., “I’m not a mussel. sickle cell anemia risk figures).
The selenium/mercury ratio is a useful parameter to identify the detoxification capacity of methylmercury in fish. Selenium is in fact capable of binding to mercury and converting it to a form that is not bio-available to the body. (8) Only busbana and limanda were not found to have significant values in the selenium/mercury ratio, which was well identified in the other species.
Ready-to-eat foods
Ready-to-eat foods made from the indicated fish and shellfish species include different formats and recipes. With the addition, in some cases, of vegetables and/or grains. Calcium, iron, copper and zinc contents were significant, selenium content decreased but remained appreciable. Conversely, heavy metals (cadmium, lead and nickel, arsenic in food obtained from mussels) are residual in low concentrations.
All foods, administered in 250 g portions, were found to meet the nutritional requirements for the age groups under consideration. Having special regard to protein and omega-3 fatty acids, iodine and other minerals, vitamins D and E. This confirms the great potential of the researched fish species, including in innovative and easy-to-eat food preparations.
Interim conclusions
Many unused fish species therefore deserve consideration in fisheries-without indulging in the exploitation of only the most commercial species-but also in aquaculture, given their nutritional properties and limited contaminant inputs.
The use of these raw materials in the production of ready-to-eat foods deserves equal consideration. Particularly where we are targeting more sensitive and discerning segments of the population, who require increased intakes of essential nutrients while at the same time requiring safe, affordable and easy-to-eat foods.
Dario Dongo and Andrea Adelmo Della Penna
On the cover an image from SEAFOODTOMORROW
Notes
(1) Ferraris et al. Francesca Ferraris, Francesca Iacoponi, Andrea Raggi, Francesca Baldi, Murielle Fretigny, Alberto Mantovani, Francesco Cubadda. Essential and toxic elements in sustainable and underutilized seafood species and derived semi-industrial ready-to-eat products. Food and Chemical Toxicology (2021), https://doi.org/10.1016/j.fct.2021.112331
(2) Bogard et al. (2019) Will fish be part of future healthy and sustainable diets? Lancet Planet. Heal. 3:e159–e160, https://doi.org/10.1016/S2542-5196(19)30018-X
(3) Loredana Spagnardi, Dario Dongo and Alessandra Mei. #poormabuoni. Savings and health in oily fish. GIFT (Great Italian Food Trade). 5/14/20, https://www.greatitalianfoodtrade.it/consum-attori/poverimabuoni-risparmio-e-salute-nel-pesce-azzurro
(4) European Food Safety Authority, NDA Panel (2014). Opinion on health benefits of seafood (fish and shellfish) consumption in relation to health risks associated with exposure to methylmercury. EFSA Journal 12(7):3761, https://doi.org/10.2903/j.efsa.2014.3761
(5) Thomsen et al. (2021). Human health risk-benefit assessment of fish and seafood: a scoping review. Crit. Rev. Food Sci. Nutr., https://doi.org/10.1080/10408398.2021.1915240
(6) SEAFOODTOMORROW. https://seafoodtomorrow.eu/
(7) Manceau et al. (2021). Demethylation of Methylmercury in Bird, Fish, and Earthworm. Environ. Sci. Technol. 55(3):1527-1534, https://doi.org/10.1021/acs.est.0c04948
(8) Yamashita et al. (2013). Selenoneine, a novel selenium containing compound, mediates detoxification mechanisms against methylmercury accumulation and toxicity in zebrafish embryo. Mar. Biotechnol. 15:559–570, https://doi.org/10.1007/s10126-013-9508-1
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
Graduated in Food Technologies and Biotechnologies, qualified food technologist, he follows the research and development area. With particular regard to European research projects (in Horizon 2020, PRIMA) where the FARE division of WIISE Srl, a benefit company, participates.
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