Research Progress on Nutritional Value, Preservation and Processing of Fish-A Review

Toxicological effects of cobalt on common carp: oxidative stress, ionic imbalance, fatty acid disruption, and gill histopathology

Cobalt (Co) is an essential element to fish and other organisms that become toxic at high concentrations. This element is emerging as a concerning pollutant in water bodies, potentially endangering the health of marine biota. The aim of this study was to investigate the short-term subcellular toxicity of cobalt in the common carp Cyprinus carpio (0, 1.13, 11.34, 22.68 and 45.37 µg/L of Co2+ for 72 h), with emphasis on oxidative balance (enzymatic and non-enzymatic antioxidants), fatty acid composition, Na+K+/Mg2+ATPases activities and histopathological changes. Co exposure increased the levels of the ferric reducing antioxidant power, hydrogen peroxide, malondialdehyde and protein carbonyl along with enzymatic and non-enzymatic antioxidant-related markers. The observed prooxidant-antioxidant imbalance in exposed fish was solidified by histological sections confirming alterations in the histomorphological structure of C. carpio gills. Results showed that increases in Co2+ exposure of fish altered the ATPases activities revealing changes in osmoregulation. Additionally, the analysis of fatty acids (FA) underscored shifts in the fish's fatty acid profile, which is indicative of Co2+ impact on C. carpio overall metabolism and immune response. Significant changes occurred in some major FA which were associated with lipid peroxidation increase and the inhibition of Na+K+ and Mg2+ ATPases activities. Overall, the current results suggest that the mechanism of Co2+ toxicity involves oxidative damage, disruption of ionic balance, cellular homeostasis and the normal physiological function of the fish gills.

Explanatory AI Predicts the Diet Adopted Based on Nutritional and Lifestyle Habits in the Spanish Population

This study used Explainable Artificial Intelligence (XAI) with SHapley Additive exPlanations (SHAP) to examine dietary and lifestyle habits in the Spanish population and identify key diet predictors. A cross-sectional design was used, employing the validated NutSo-HH scale to gather data on nutrition, lifestyle, and socio-demographic factors. The CatBoost method combined with SHAP was applied. The sample included 22,181 Spanish adults: 17,573 followed the Mediterranean diet, 1425 were vegetarians, 365 were vegans, and 1018 practiced intermittent fasting. Fish consumption was the strongest dietary indicator, with vegans abstaining and some vegetarians consuming it occasionally. Age influenced diet: younger individuals preferred vegan/vegetarian diets, while older adults adhered to the Mediterranean diet. Vegans and vegetarians consumed less junk food, and intermittent fasters were more physically active. The model effectively predicts the Mediterranean diet but struggles with others due to sample imbalance, highlighting the need for larger studies on plant-based and intermittent fasting diets.

New Perspectives on Canned Fish Quality and Safety on the Road to Sustainability

Canning extends the shelf life of seafood products while preserving their quality. It is increasingly considered a more sustainable food processing method due to the primary fishing methods used for key species and the lower energy costs compared to the production of fresh and frozen fish. However, canning can change key components, allow some contaminants to persist, and generate undesirable compounds. This review revisits the effects of canning on product quality and highlights the potential hazards that may compromise safety. It also examines emerging trends in product development, particularly novel formulations aimed at optimizing nutritional value while maintaining safety standards without compromising sustainability. Overall, the quality of most canned seafood meets industry requirements, for example, with improvements in processing strategies and strict safety protocols, leading to reduced histamine levels. However, data on marine biotoxins and microplastics in canned seafood remain limited, calling for more research and monitoring. Environmental contaminants, along with those generated during processing, are generally found to be within acceptable limits. Product recalls related to these contaminants in Europe are scarce, but continuous monitoring and regulatory enforcement remain essential. While new formulations of canned fish show promise, they require thorough evaluation to ensure both nutritional value and safety.

A preliminary exploration of the synergistic preservation effect of electrostatic field and superchilling on muscle foods: Mechanisms, influencing factors, applications, and challenges

Muscle foods that are highly perishable require effective preservation technologies to maintain their quality and extend their shelf life. Electrostatic field (EF) treatment, superchilling (SC), and their combined technologies have received attention for their effectiveness in improving muscle food quality. However, the lack of a comprehensive understanding of their mechanism and combined effects on muscle foods has limited their application. Therefore, the review began with a discussion of the mechanisms, influencing factors, and equipment development underlying EF treatment and SC of muscle foods. It then reviewed the research progress made to date and highlighted the effects of these technologies on various quality attributes, such as texture, color, and nutritional value. Additionally, the review explored the potential synergistic effects of combining these technologies and discussed how they could complement each other to achieve superior preservation outcomes. The EF significantly improves muscle food quality by inhibiting ice crystal growth, blunting enzyme activity, causing microbial electroporation, and generating ozone. SC technology utilizes low temperatures to form an ice crystal shell, effectively inhibiting the reproduction of microorganisms and passivating the activity of enzymes, thereby extending the shelf life. The combination of the two, through the dual inhibition of bacteria and enzymes and the regulation of ice crystals, can build an excellent preservation system to bring a better preservation effect for muscle foods. Future research should prioritize safety issues, equipment cost, and process optimization while exploring innovative applications. This will provide theoretical and technical support for the progress of muscle food preservation technology.

Fish handling and postharvest losses around the Fincha'a, Amarti, and Nashe reservoirs in Oromiya, Ethiopia

This study assessed the factors contributing to postharvest loss of fish around the Fincha'a, Amarti, and Nashe reservoirs in Horro Guduru Wollega, Oromia, Western Ethiopia, using semi-structured questionnaires from January, 2022 GC onward. The aim of the finding was to know the fish handling and post-harvest preservation of fish around the reservoirs. In the study area, 320 respondents were selected using a random sampling system. Findings revealed that 61.1% of respondents consume fish without processing, with only 20.8% using salting and 18.1% practicing drying. The drying process notably affected texture, smell, and color. Most respondents (91.7%) preferred fresh fish due to financial constraints, lack of awareness, and market access. Species preference (40.3%), quality (33.3%), and market demand (23.6%) influenced pricing. Transportation is often done using donkey-back loads that could increase the risk of fish contamination. Although 50% of respondents stored harvested fish for one day without treatment, among these, 88.9% reported no spoilage within a day. Handling materials varied, with metal containers (33.3%) being the most common. Fish is primarily consumed as stew (39.4%) in the study area. Among these, almost all (91.9%) enjoy eating fish. However, it is often viewed as food for children and for the poor by many of them (60.6%). Despite concerns over fish bones and odors of the fish, 80.6% reported no health issues related to consumption. Most respondents (90.3%) discarded spoiled fish due to a lack of training in fish harvesting and preservation. The study indicates that postharvest losses are minimal due to effective harvesting methods, with immediate consumption practices prevalent in the community.

Nationwide survey in Korea for risk assessment of pesticide residues in fishery and seaweed products

Pesticide residues in fishery products are a concern due to environmental contamination. However, it is not sufficiently managed because of a lack of established standards. This study was conducted to monitor pesticide residues in fishery and seaweed product samples and assess the risk to humans. A total of 454 fishery products and 38 seaweed products were examined, and seven pesticides were detected. Among these, ethoxyquin was the most frequently detected. The risk of ethoxyquin via chronic exposure was 0.16 % and 83 % for the average and 97.5th intake, respectively. A risk exceeding 80 % is concerning; however, this concentration is considered safe in real-world circumstances, such as washing and cooking processes. Therefore, the detected pesticide residues in this study were assessed to be safe level for Korean intake level of fishery products. However, DDT, the prohibited pesticide decades ago, was still found and it is necessary to keep monitor considering persistent of pesticides. Considering newly regulated pesticides, sufficient monitoring and risk assessment data such as this study should be provided for policy standards setting and management.

Marine-Derived Bioactive Ingredients in Functional Foods for Aging: Nutritional and Therapeutic Perspectives

Aging is closely linked to various health challenges, including cardiovascular disease, metabolic disorders, and neurodegenerative conditions. This study emphasizes the critical role of bioactive compounds derived from marine sources, such as antioxidants, omega-3 fatty acids, vitamins, minerals, and polysaccharides, in addressing oxidative stress, inflammation, and metabolic disorders closely related to aging. Incorporating these materials into functional foods not only provides essential nutrients but also delivers therapeutic effects, thereby promoting healthy aging and mitigating age-related diseases. The growth of the global anti-aging market, particularly in North America, Europe, and Asia, underscores the significance of this study. This review systematically analyzes the current research, identifying key bioactive compounds, their mechanisms of action, and their potential health benefits, thus highlighting the broad applicability of marine-derived bioactive compounds to enhancing healthy aging and improving the quality of life of aging populations.

Comparative Analyses of Muscle Quality in Hooked, Trawl-Net, and Radar-Net Hairtail (Trichiurus haumela) during Thermal Processing

To investigate and compare the changes in muscle quality of hooked, trawl-net, and radar-net hairtail (Trichiurus haumela, HH, TH, and RH) during thermal processing, the physicochemical properties of three kinds of hairtail were determined under heating at 30, 50, 70 and 90 °C for 10 min. Additionally, the muscle tissues were observed via Oil Red O (ORO) staining, Masson staining, and scanning electron microscopy (SEM). The results showed that with increased heating temperature, pH, L*, b*, chewiness, and gumminess in hairtail muscle increased, while a* and shearing force decreased. The springiness, relative contents of hydrophobic and disulfide bonds, myosin surface hydrophobicity, and TCA-soluble peptide content increased first and then decreased. However, the relative contents of ionic and hydrogen bonds showed an opposite trend. Histological observations revealed that heating disrupted hairtail muscle tissue, manifested by the blurriness and disorder of myofibrils and breakage of myofibrillar bundle membranes. The RH muscle exhibited the highest chewiness, gumminess, and chemical force levels, accompanied by the lowest content of TCA-soluble peptide. Furthermore, the RH muscle presented the greatest fat droplet content, diffusivity, and integrity of collagen and myofibers. Correlation analysis revealed a close correlation between muscle quality and protein function in HH, TH, and RH. This study provides a theoretical basis for the difference in muscle quality in three different types of hairtail.

Assessment of cooking methods and freezing on the nutritional value and health risks of heavy metals in four fish species consumed in Douala, Cameroon

The effects of smoking, boiling and freezing on the nutritional value and health risks of heavy metals in four fish species consumed in Douala was investigated. Fish samples from Cyprinus carpio, Arius parkii, Ethmalosa fimbriata and Polydactilis quadrifilis were collected at the Douala Fishing seaport, carried to the laboratory, washed with distilled water and processed. Proximate composition, mineral content, heavy metals and lipid quality were analyzed using AOAC standard methods. Estimated Daily Intake (EDI), Targeted Hazard Quotient (THQ), Hazard Index (HI) and Carcinogenic Risk (CR) were used to estimate the human health risk. Results showed that smoking and boiling increased significantly (P < 0.05) protein and ash levels. Lipid were reduced significantly (P < 0.05) with boiling and freezing compared to raw and smoked sample. Smoking increased significantly (P < 0.05) cadmium, lead, mercury and arsenic contents compared to boiling and freezing. EDI values of cadmium in all species of fish smoked were not acceptable for human consumption. THQ values of mercury in raw, smoked, boiled and frozen were not acceptable for human consumption. HI suggested a non potential carcinogenic effect for all fish while CR for cadmium and arsenic suggested a carcinogenic health risk for Arius parkii (smoked and boiled). All treatment decreased significantly (P < 0.05) iodine value and increased acid, peroxide, anisidine values, thiobarbituric acid reactive substances and total oxidation index compared to raw fish. Boiling was the best cooking method compared to smoking.

Evaluation of the toxic metals, proximate composition and length-weight relationships of selected fish species from the Gadananathi River, Southern Tamil Nadu

The present study reveals toxic metals, proximate composition, and growth conditions in seven fish species, aiding their nutritional importance and conditions. The samples of seven different small indigenous fish species, including Xenentodon cancila, Glossogobious giuris, Pseudambassis ranga, Puntius dorsolis, Mystus vittatus, Dawkinsia filamentosa, and Dawkinsia tambraparaniei, were collected in river Gadananathi, Tamilnadu, India. A total 14 fish samples were analyzed for lead, cadmium, and copper using atomic absorption spectrometry. The standard procedures were used to determine the length-weight and proximate composition of the seven fishes. The findings revealed that the seven fish species had variable amounts of metal buildup. Cu levels were highest in D. tambraparniei gills and lowest in M. vittatus gills and livers; nonetheless, substantial amounts of Cu were found in P. dorsalis livers. In the length-weight correlations of the regression parameters of coefficient value r2, the "a" and "b" values revealed a positive allometric growth rate in all fish species except G. giuris and M. vittatus. However, X. cancila had the highest composition in the proximate analysis, while D. tambraparniei and D. filamentosa had the highest protein content mean value at a significant level (P ≤ 0.05). Overall, discrepancies in nutritional content might be related to species, environmental circumstances, fish age and size, and food availability.

Effect on nutritional quality changes in fresh and canned Scomber australasicus and Scomberomorus guttatus

The purpose of present research was to investigate the effect of different storage periods on nutrients composition of the two the fish species. In the present study, proximate composition, energy values and oil indexes of two the fish species Scomber australasicus and Scomberomorus guttatus were determined. The lipid content of the fresh S. guttatus was found significantly higher than the S. australasicus (p < .05). The S. australasicus after 2 months storage found lowest calorie value (275.5 kcal/kg). The calorie values of S. australasicus after 4 months storage was 292.5 kcal/kg and for S. guttatus after 6 months storage (375.70 kcal/kg) found highest. The number of acidic and peroxide for both types of fish after 2 months storage found 2.66 mg KOH/g and 4.22 meqO2/kg for S. australasicus, and found 2.47 mg KOH/g and 3.76 meqO2/kg for S. guttatus which were lowest compared to the other two treatments. The storage periods after the canning process led to a decrease in protein and moisture contents and increase in the lipid content of the canned tuna. The calorie level was related to the parameters such as fat level of the processed S. guttatus after 6 months storage which lead to high calorie level (375.70 kcal/kg-1), while processed S. australasicus after 2 months storage with lower fat content (15.1%) had lower energy value (275.5 kcal/kg-1). The highest acidic, and peroxide value for treatment 6 months storage for canned fish S. guttatus was 4.34 ± 0.36 mg KOH/g, and 5.74 ± 0.25 (meqO2/kg), while for S. australasicus was 4.21 ± 0.34 mg KOH/g, and 6.67 ± 0.23 (meqO2/kg), It can be concluded for fish 6 months storaged S. guttatus, shelf life increased the and can be stored for several years.

Toward Sustainable and Healthy Fish Products-The Role of Feeding and Preservation Techniques

Fish is a fundamental component of the human diet, and in the near future the proportion of aquatic foods originating from aquaculture production is expected to increase to over 56%. The sustainable growth of the aquaculture sector involves the use of new sustainable raw materials as substitutes for traditional fishmeal and fish oil ingredients, but it is crucial that the substitution maintains the nutritional value of the fish meat. In addition, the preservation of the nutritional value should be a mandatory requirement of new technologies that extend the shelf life of fish. In this context, we evaluated the impact of a newly formulated feed and three preservation treatments (brine, pulsed electric field (PEF), and PEF plus brine) on the fatty acid composition and protein and lipid digestibility of sea bass fillets. In non-digested fillets, although slightly reduced by the newly formulated feed (standard = 2.49 ± 0.14; newly formulated = 2.03 ± 0.10) the n-3/n-6 PUFA ratio indicated good nutritional value. The preservation treatments did not modify the fatty acid content and profile of non-digested fillets. Conversely, protein and lipid digestibility were not affected by the different diets but were significantly reduced by brine, with or without PEF, while PEF alone had no effect. Overall, our results indicated that the newly formulated feed containing 50% less fishmeal is a good compromise between the sustainability and nutritional value of cultivated seabass, and PEF is a promising preservation technology deserving of further study.

Toxicological effect of endocrine disrupting insecticide (deltamethrin) on enzymatical, haematological and histopathological changes in the freshwater iridescent shark, Pangasius hypothalamus

This study investigated the deltamethrin (DMN) induced harmful effects on Pangasius hypophthalmus using enzymatic activity, haematological, and histopathological changes. LC50 value was 0.021 mg/L at 96 h, and sublethal toxicity was tested for 45 days at two `concentrations (i.e., 1/5th and 1/10th of LC50). Haematological parameters and enzymatic activities significantly changed between DMN-exposed and control groups (p < 0.05). Histopathologically, both DMN doses induced liver hyperemia, hepatic cell rupture, necrosis, hypertrepheoid bile duct, shifting nuclei, vascular haemorrhage, and hepatocyte degeneration, while in gill, secondary lamellae destruction, a fusion of adjacent gill lamellae, hypertrophy, hyperplasia, adhesion, and fusion were noticed. Kidney developed melanomacrophages, increased periglomerular and peritubular space, vacuolation, decreased glomerulus, hyaline droplets in tubular cells, loss of tubular epithelium, distal convoluted segment hypertrophy, and granular layer in brain pyramid and Purkinje cell nucleus. But, limiting pesticide impacts on freshwater fish and their habitat requires a holistic, cradle-to-grave approach and toxicological studies.

Nutritional composition, heavy metal contents and lipid quality of five marine fish species from Cameroon coast

The nutritional value, heavy metal content and lipid quality of five marine fishes from, Cameroon coast were be investigated. Fish samples from Ilisha africana, Sardinella, maderensis, Cyprinus carpio, Arius parkii and Ethmalosa fimbriata were collected at, the Douala sea port, carried to the laboratory, washed with distilled water and, processed. Proximal composition, minerals, lipid quality and heavy metal analyses, were performed using AOAC standard methods. Results show that proteins (18.43%), and lipids (3.69%) contents were higher in Ilisha africana. Cyprinus carpio had the, highest ash content (4.59%). Contents of minerals and heavy metals were found as, follows: P > Mg > K > Ca > Na > Fe > Zn > Cu > Mn and Hg > Pb > Cd > As. Oils extracted from C. carpio, A. parkii and E. fimbriata were semi-siccative while those of I. africana and S. maderensis were siccative. Thus, these fish species are good sources of proteins and, minerals that can be used for managing mineral deficiencies in humans and animals.