EPA + DHA intake in land-locked central Europe (CE) is barely fulfilled. Imported marine fish/farmed salmonids are likely the backbone of an ailing EPA + DHA security. Supplementing with captured marine fish oil capsules (~0.5 g up to 1.6 g CO2-eq. mg EPA + DHA-1) could be comparable in GHG emissions with fish consumption itself (~1 g to as low as 0.6 g CO2-eq. mg EPA + DHA-1). But synergistic benefits of EPA + DHA intake by consuming fish protein need consideration too. Taking semi-intensive pond carp and intensively farmed salmon as models, we analyzed footprint, eco-services, and resource use efficiency perspectives of achieving EPA + DHA security in a CE region. Despite a lower production footprint, pond-farmed fish greatly lag in EPA + DHA supply (carp 101-181 mg 100 g-1 < salmon 750-1300 mg 100 g-1). It doubles-to-quadruples footprint 'per mg' of EPA + DHA: nitrogen (carp 18.3 > salmon 8.7 mg N), phosphorus (carp 6.8 > salmon 1.6 mg P), and climate change (carp 1.84 > salmon 0.8 g CO2-eq.). With enhancements in pond carp (>300 mg EPA + DHA 100 g-1), these differences may cease to exist. Harnessing EPA + DHA bioaccumulation pathways active in ponds, finishing feeding strategies, and polyculture, the EPA + DHA content in pond fish may be increased. Ecosystem services with EPA + DHA mining from pond food web or high EPA + DHA output-to-input ratio (pond carp 1-200 > RAS salmon 0.75) make ponds an eco-efficient system. As fish consumption in CE must improve, pond-farmed fish would be needed to complement (but not substitute) salmonid/marine fish/oil capsules consumption. Achieving EPA + DHA security with minimum pressure on the environment or global resources.

• Publication type
• Journal Article MeSH

Measures for consumer protection against food adulteration and misleading labelling are integrated into EU legislation, including methods for detecting misleading practices. Verification of the meat content is available for marine products, but not for salmonid fish due to the lack of standard nitrogen factors. This study aimed to establish nitrogen factors for rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis). The study analysed 340 fish from Czech fisheries obtained in the summer of 2018-2020. According to the established ISO methods, fillet samples with and without skin were analysed for their nitrogen content (protein), dry matter, ash, and fat. The recommended nitrogen factor for rainbow trout fillets with and without the skin is 3.07 ± 0.12 and 3.06 ± 0.14, respectively, and the nitrogen factor for fat-free rainbow trout fillets with and without the skin is 3.33 ± 0.15 and 3.29 ± 0.15, respectively. The recommended nitrogen factor for brook trout fillets with and without the skin is 3.16 ± 0.10 and 3.12 ± 0.09, respectively, and the nitrogen factor for fat-free brook trout fillets with and without the skin is 3.42 ± 0.13 and 3.36 ± 0.12, respectively. The established nitrogen factors will enable the analysis of the meat content to ensure that consumers purchase correctly described and labelled fish products.

• Keywords
• adulteration, fish products, fish-food fraud, nitrogen factor, salmonid,
• Publication type
• Journal Article MeSH

Proximate and fatty acid (FA) composition of seven freshwater fish species from the Czech Republic were examined. Moreover, the index of atherogenicity (IA) and the index of thrombogenicity (IT) were calculated from the obtained data. These two indices along with the total content of the essential n-3 FAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as well as the ratio of n-6/n3 FAs, provide good indicators for the nutritional value of the fish. The species had been selected owing to the limited amount of information about their nutritional composition available. Furthermore, they are not typically subject to aquaculture, being almost exclusively obtained by angling. The protein content was relatively stable in all species (17.1 ± 1.55 to 19.2 ± 2.20 g/100 g). The content of carbohydrates ranged from 0.02 ± 0.1 to 0.99 ± 0.0 g/100 g and ash from 1.08 ± 0.20 to 2.54 ± 1.57 g/100 g. As expected, a high variability was observed in the fat content (0.74 ± 0.04 to 4.04 ± 0.81 g/100 g) and the FA composition, as well as the contents of EPA and DHA. IA and IT were close to the values stated for the Eskimo diet, indicating a high nutritional value with a positive effect for human health.

• Keywords
• Docosahexaenoic acid, Eicosapentenoic acid, Index of atherogenicity, Index of thrombogenicity, Nutritional value,
• Publication type
• Journal Article MeSH