Search Results (19)

Lionfish (Pterois miles), an invasive species in the Mediterranean, pose ecological and socioeconomic challenges. This study examines the seasonal variation in the nutritional composition and technical quality of lionfish from the Ionian and Aegean Seas, evaluating their potential as a food resource. Fillets were high in protein (19.4%) and low in fat (2.0%), with significant seasonal differences in the Ionian Sea, where winter samples had higher lipid content. The fillet yield (28.4%) was satisfactory given the fish’s morphology. Fatty acid analysis confirmed lionfish as a valuable source of polyunsaturated fatty acids (PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with EPA + DHA levels exceeding the recommended daily intake (119.2%). Seasonal variations in fatty acid composition were observed, including higher EPA in autumn and lower lipid nutritional quality in summer. Arachidonic acid (ARA) was also present at nutritionally significant levels (79.4 mg/100 g). The n3/n6 ratio (2.2) and favourable atherogenic and thrombogenic indices highlight its nutritional benefits. This is the first study to assess seasonal variations in the nutritional value and technical yield of lionfish in the Mediterranean, offering novel insights into its commercial valorisation. These findings support its promotion as a sustainable protein source and as a means of managing its invasive population. Full article

The aim of this work was to introduce the by-products generated by the sea bream processing industry as a new ingredient in the production of fish and seafood burgers. Fish by-product flour was obtained and added in the preparation of sea bream and shrimp burgers. The formulations selected from a sensory evaluation with semi-trained assessors were burgers with sea bream and shrimp (C) and the same sample with 10% of by-product flour (BP10). These formulations were subjected to sensory evaluation with consumers using hedonic scales. Both samples had a good acceptability, although the presence of by-products had a negative impact on the colour, resulting in a slight decrease in the global acceptance. It would be interesting to use a natural ingredient that could improve the colour of the product or use the by-product flour in battered products where the colour could be masked. Full article

With the aim to upcycle fish side-streams, enzymatic hydrolysis is often applied to produce protein hydrolysates with bioactive properties or just as a protein source for food and feed. However, the production of hydrolysates generates a side-stream. For underutilized fish and fish backbone this side-stream will contain fish bones and make it rich in minerals. The aim of this study was to assess the relative bioaccessibility (using the standardized in vitro model INFOGEST 2.0) of minerals in a dietary supplement compared to bone powder generated after enzymatic hydrolysis of three different fish side-streams: undersized whole hake, cod and salmon backbones consisting of insoluble protein and bones. Differences in the bioaccessibility of protein between the powders were also investigated. The enzyme hydrolysis was carried out using different enzymes and hydrolysis conditions for the different fish side-streams. The content and bioaccessibility of protein and the minerals phosphorus (P), calcium (Ca), potassium (K) and magnesium (Mg) were measured to evaluate the potential of the powder as an ingredient in, e.g., dietary supplements. The bone powders contained bioaccessible proteins and minerals. Thus, new side-streams generated from enzymatic hydrolysis can have possible applications in the food sector due to bioaccessible proteins and minerals. Full article

In response to the exponential growth in world population, there has been a striking surge in the volume of discarded fish worldwide. This surge is particularly evident in the fish processing industry, where a substantial amount of waste is generated, posing significant environmental concerns. Consequently, the repurposing and utilisation of these waste materials have emerged as pivotal processes for the preservation of marine resources. By employing innovative strategies, valuable products can be extracted from these fish by-products, offering not only economic advantages but also contributing to mitigating environmental impacts. This comprehensive literature review focuses on exploring diverse avenues for using fish waste and extracting high-value materials such as bioactive peptides, collagen, and enzymes, elucidating their potential applications across various industries. The literature review also demonstrates the possibility of extracting various bio-compounds from highly diverse fish waste. It has been observed that there is a need for optimisation of extraction protocols, as the variation in extraction methods and respective conditions significantly affects the extraction yields of the products. Moreover, considering our specific interest in the fish species endemic to The Azores, a meticulous characterisation will be conducted, as there is limited knowledge about waste utilisation processes specific to this archipelago. Full article

This work describes the development of a ready-to-eat (RTE) product based on an equal mixture of fish mince from three undervalued fish species with different fat contents and protein gelling capacity, which was enriched with fish oil entrapped in a κ-carrageenan egg white fish protein hydrolysate powder, obtained by either spray drying (SD) or heat drying (HD) at 80 °C (HD80). Previously, the spray-dried (SD) powder and heat-dried powders obtained at 45 °C, 60 °C and 80 °C (HD45, HD60 and HD80) were characterised in terms of water solubility, lipid oxidation (TBARS), hygroscopicity and ζ potential. All HD powders showed higher hygroscopicity and lower TBARS than the SD powder. The dry powder was incorporated into a blend composed of salt-ground batter and raw mince to improve binding and textural properties. Changes in water-holding capacity, colour, shear strength and microorganisms were monitored during the processing steps. The RTE product presented a high protein content and a noticeable amount of long-chain ω-3 fatty acids. The use of undervalued fish species together with fish oil and a protein hydrolysate from fish waste contribute to improving the sustainability of fishery resources, being conducive to obtaining a potentially functional RTE product. Full article

The fishery industry generates large amounts of waste (20–75% (w/w) of the total caught fish weight). The recovery of bioactive compounds from residues and their incorporation in cosmetics represents a promising market opportunity and may contribute to a sustainable valorisation of the sector. In this work, protein-rich extracts obtained by high-pressure technologies (supercritical CO₂ and subcritical water) from sardine (Sardina pilchardus) waste and codfish (Gadus morhua) frames were characterized regarding their cosmeceutical potential. Antioxidant, anti-inflammatory and antibacterial activities were evaluated through chemical (ORAC assay), enzymatic (inhibition of elastase and tyrosinase), antimicrobial susceptibility (Klebsiella pneumoniae, Staphylococcus aureus and Cutibacterium acnes) and cell-based (in keratinocytes-HaCaT) assays. Sardine extracts presented the highest antibacterial activity, and the extract obtained using higher extraction temperatures (250 °C) and without the defatting step demonstrated the lowest minimum inhibitory concentration (MIC) values (1.17; 4.6; 0.59 mg/mL for K. pneumoniae, S. aureus and C. acnes, respectively). Codfish samples extracted at lower temperatures (90 °C) were the most effective anti-inflammatory agents (a concentration of 0.75 mg/mL reduced IL-8 and IL-6 levels by 58% and 47%, respectively, relative to the positive control). Threonine, valine, leucine, arginine and total protein content in the extracts were highlighted to present a high correlation with the reported bioactivities (R² ≥ 0.7). These results support the potential application of extracts obtained from fishery industry wastes in cosmeceutical products with bioactive activities. Full article

Anaerobic digestion is a promising method of organic waste valorisation, particularly for fish farm waste, which has experienced a high growth rate in recent years. The literature contains predictive mathematical models that have been developed by various authors, allowing the prediction of the composition of bio-gas production from organic waste. In general, Monod’s kinetic expression is the basis for describing the enzymatic reaction rates for anaerobic digestion. In this work, several parameters are taken into account, such as temperature, cell growth inhibition, and other operating parameters, and systems of differential equations coupling the kinetics and stoichiometry for bio-reactions are applied to better describe the dynamics. Because of the high number of initial parameters that need to be defined for the anaerobic digester, the use of this model requires significant resources and a long calculation time. For this reason, a global sensitivity analysis (GSA) is applied to this predictive model based on the Sobol index method, in order to identify the most influential key parameters and the interactions between them. For the digestion of fish waste, it is observed that the key parameters influencing methane production are the lipid concentration of the waste, temperature, and hydraulic retention time (HRT). Full article

Japanese Spanish mackerel (JSM) (Scomberomorus niphonius) is a marine fish species containing health-beneficial polyunsaturated fatty acids (PUFAs). In the present study, the quality of JSM by-products oils extracted by supercritical CO₂ (SC-CO₂) and organic solvent extraction was compared in terms of physico-chemical properties of the oils. Eicosapentaenoic acid (EPA) is one of the important polyunsaturated fatty acids present in SC-CO₂-extracted skin and muscle oil 5.81 ± 0.69% and 4.93 ± 0.06%, respectively. The amount of docosahexaenoic acid (DHA) in SC-CO₂-extracted skin and muscle oil was 12.56 ± 0.38% and 15.01 ± 0.28%, respectively. EPA and DHA are considered as important PUFAs for the development of brain function and the prevention of coronary heart diseases. Extracted oils showed considerable antioxidant activity. In the obtained oils, atherogenic index (AI) values varied from 0.72 to 0.93 and thrombogenic index (TI) ranged from 0.75 to 0.92, which is considered an acceptable level. Fatty acid composition, bio potentiality, thermogravimetric, and vitamin D analysis showed that oils extracted from JSM by-products can be a good source of oil for application in food, pharmaceutical and cosmetic industries. Therefore, the present research revealed the potentiality of green valorisation of S. niphonius by-products as a possible sustainable approach for targeting the era of zero waste. Full article

The Common Fisheries Policy of the European Union was reformed in 2013 with the aim of improving the sustainability of the fishing sector. The Landing Obligation, a cornerstone of this reform, requires fishers to land their unwanted catch instead of discarding it at sea. Existing literature pays little attention to what becomes of this unwanted catch once it is landed. To further the discourse on the sustainable valorisation of unwanted catch, this study explores whether unwanted catch that is safe for human consumption could be used for improving food security. The paper focuses on Dutch food banks, which deliver critical food aid to over 160,000 individuals yearly but struggle to provide all dependant recipients with nutritionally balanced food parcels. The research question is addressed in two ways. The food bank recipients’ willingness to consume UWC is evaluated quantitatively through a survey. Next to this, data from interviews with relevant stakeholders are analysed qualitatively. Results indicate that the Food Bank Foundation and its recipients are willing to receive this fish if it is safe to consume and accessible. However, various factors such as existing infrastructure, lack of economic incentive to donate, competition from non-food and black markets, and the fishing industry’s conflict with the landing obligation might pose barriers to this kind of valorisation. The dissonance between fisheries, food, and sustainability policies is discussed and identified as a key limiting factor. To bridge the differences between these policy areas, we propose public-private partnerships and voluntary agreements among involved stakeholders. Full article

Several anchovies species are captured all over the world; they are consumed fresh but also preserved by the industry, either by brine-fermentation or canning in oil. The industrial process generates large amounts of residue (about 50% of the original fish biomass) that is generally used to produce fish flour. In this paper, the advancement of a recently proposed process for the full valorisation of anchovies aimed at the extraction of fish oil (to be used as an omega-3 source) and at the production of biomethane through anaerobic digestion is presented. Particularly, in the experiments presented, a co-digestion of anchovy sludge—used as a nitrogen supplement—and market waste (5% and 95% on a Total Solids basis) was performed. Since the proposed extraction process uses, as a green-solvent, d-limonene, the well-known problems of toxicity for the anaerobic biomass must be overcome during the digestion process. As discussed below, the granular activated carbon (GAC) is used to reclaim and improve anaerobic digestion processes in a reactor displaying clear signs of inhibition. In fact, GAC demonstrates multiple benefits for anaerobic digestion, such as adsorption of toxic substances, biomass selection, and triggering of direct interspecies electron transfer (DIET). Full article

Fish side streams represent between 20–80% of the weight of fish, and their disposal represents an environmental and economic problem. These side streams contain proteins and antioxidant compounds that give them added value. In order to valorise these side streams, an extraction assisted by pulsed electric fields (PEF) was carried out to obtain proteins and compounds with antioxidant activity. An extraction for the same time but without PEF pre-treatment was used as a control. The side streams used were head, skin, viscera and backbone from sea bass. The antioxidant capacity was measured by two complementary methods, TEAC and ORAC. The results showed that in the case of head and skin, treatment with PEF notably improved protein extraction by 37.7 and 37.8%, respectively. However, for viscera, the best values were achieved with the control extraction. Finally, backbone did not show significant differences in protein recovery between PEF-assisted extraction and control extraction. Regarding antioxidant capacity, the results followed the same trend as for proteins. For head and skin, the pre-treatment with PEF increased the extraction of antioxidant compounds, improving the TEAC values by 21.74 and 29.11%, respectively. On the other hand, ORAC results increased 22.11% for head extracts and 40.93% for skin extracts. In the extracts obtained from the viscera, the TEAC and ORAC values were better in the control sample, being 21.43% and 24.82% higher, respectively. The antioxidant compounds present in the samples may be bioactive peptides, but a more exhaustive analysis using chromatographic techniques would be necessary to complete the information. Therefore, it has been seen that PEF-assisted extraction can be a good strategy to increase the recovery of proteins and antioxidant compounds from fish side streams such as head or skin, but not for viscera and backbone. Full article

One third of food produced globally is wasted. Disposal of this waste is costly and is an example of poor resource management in the face of elevated environmental concerns and increasing food demand. Providing this waste as feedstock for black soldier fly (Hermetia illucens) larvae (BSFL) has the potential for bio-conversion and valorisation by production of useful feed materials and fertilisers. We raised BSFL under optimal conditions (28 °C and 70% relative humidity) on seven UK pre-consumer food waste-stream materials: fish trimmings, sugar-beet pulp, bakery waste, fruit and vegetable waste, cheese waste, fish feed waste and brewer’s grains and yeast. The nutritional quality of the resulting BSFL meals and frass fertiliser were then analysed. In all cases, the volume of waste was reduced (37–79%) and meals containing high quality protein and lipid sources (44.1 ± 4.57% and 35.4 ± 4.12%, respectively) and frass with an NPK of 4.9-2.6-1.7 were produced. This shows the potential value of BSFL as a bio-convertor for the effective management of food waste. Full article

Seafood by-products, produced by a range of different organisms, such as fishes, shellfishes, squids, and bivalves, are usually discarded as wastes, despite their possible use for innovative formulations of functional foods. Considering that “wastes” of industrial processing represent up to 75% of the whole organisms, the loss of profit may be coupled with the loss of ecological sustainability, due to the scarce recycling of natural resources. Fish head, viscera, skin, bones, scales, as well as exoskeletons, pens, ink, and clam shells can be considered as useful wastes, in various weight percentages, according to the considered species and taxa. Besides several protein sources, still underexploited, the most interesting applications of fisheries and aquaculture by-products are foreseen in the biotechnological field. In fact, by-products obtained from marine sources may supply bioactive molecules, such as collagen, peptides, polyunsaturated fatty acids, antioxidant compounds, and chitin, as well as catalysts in biodiesel synthesis. In addition, those sources can be processed via chemical procedures, enzymatic and fermentation technologies, and chemical modifications, to obtain compounds with antioxidant, anti-microbial, anti-cancer, anti-hypertensive, anti-diabetic, and anti-coagulant effects. Here, we review the main discards from fishery and aquaculture practices and analyse several bioactive compounds isolated from seafood by-products. In particular, we focus on the possible valorisation of seafood and their by-products, which represent a source of biomolecules, useful for the sustainable production of high-value nutraceutical compounds in our circular economy era. Full article

Climate changes are nowadays reality and affect all aspects of everyday life. One of the places where these changes influence the society the most is the Brazilian Ceará region and Jaguaribara basin that suffer long-lasting, devastating drought cycles. They have a dramatic negative impact on local economy, forcing change in business models. This work presents the valorisation of wastes and residues from local fish, prawns, and the vegetable-cultivation industry via biogas production forced to adapt to these new circumstances. Along a single year, as much as 189.74 tonnes of wastes and residues can be processed by the biogas production facility, producing as much as 94 GJ of cooling energy and 1 tonne of biofertiliser monthly. Even for such a small biogas production facility, the NPV is positive already after 11 years; its IRR is 6.2%, and accumulated ROI for 20 years of operation is as high as 77.8%. This work demonstrates that a valorisation of industrial wastes and residues via biogas production is a feasible solution for a specific industrial scenario addressing new socio-economic challenges for the particular enterprise. Full article

Overfishing is increasing over time, and according to FAO (Food and Agriculture Organization), about one third of the world’s fish stocks are now overfished. Thus, diversifying the target species is essential for fisheries sustainability contributing to improve resource-efficient processes. Non-target species can be valuable resources for the development of new food products. However, those species are scarcely studied, and it is of high importance to trace their seasonal sensory profile as a first step towards their valorisation. Therefore, in this study, seasonal influence on sensory properties of five low commercial value or unexploited fish species, namely Trachurus picturatus (blue jack mackerel), Spondyliosoma cantharus (black seabream), Trigla lyra (piper gurnard), Serranus cabrilla (comber) and Capros aper (boarfish), was assessed in order to identify the most favourable season for catching each species. Fish samples were assessed by a panel of 16 semi-trained assessors for sensory attributes previously identified. The evaluation takes place every 2 months. Statistical differences were reported between attributes and seasons for all species, except for T. lyra, which did not present any difference in its sensory attributes throughout the year. Full article