Search Results (430)

The silver pomfret (Pampus argenteus) is a high-value marine food fish, but its aquaculture is limited by juvenile intestinal immaturity, characterized by impaired digestion, barrier dysfunction, and microbial dysbiosis. This study evaluated whether early-life dietary inulin could improve intestinal health and muscle nutritional composition. After an 8-week feeding trial, fish fed a 5 g/kg inulin-supplemented diet showed improved growth performance, as reflected by higher final body weight (+17.2%), WGR (+18.5%), and SGR (+6.4%) than the control group. These benefits were associated with enhanced intestinal morphology, increased α-amylase and lipase activities, upregulated expression of tight junction genes, and a remodeled gut microbiota. These gut-associated changes were accompanied by improved selected muscle compositional traits. Specifically, inulin supplementation enriched essential amino acids, including methionine and threonine, as well as flavor-related amino acids, such as glutamate, glycine, and serine. Meanwhile, the muscle lipid profile was also modified, as reflected by reduced levels of selected saturated fatty acids and increased levels of monounsaturated fatty acids, particularly oleic acid. Collectively, our findings suggest that early-life dietary supplementation with 5 g/kg inulin may support intestinal homeostasis-related indicators and improve selected muscle nutritional traits in farmed silver pomfret. Full article

To address the quality divergence between wild and cage-farmed red sea bream (Pagrus major), we conducted a comparative analysis of their proximate composition, fatty acid and amino acid profiles, and chromatic characteristics across varying size and growth stages. Farmed fish exhibited substantial lipid deposition (peaking at 4.77% in F4), yielding a high relative percentage of n-3 long-chain polyunsaturated fatty acids. In contrast, wild fish maintained a leaner muscle profile (<2.43% lipid) and were uniquely characterized by an elevated abundance of C22:1n-9 (up to 11.52%), distinguishing them from farmed cohorts. Regarding sensory quality, large-sized wild specimens contained significantly higher concentrations of delicious amino acids (DAA, up to 8.83 g/100 g), particularly glycine and alanine, indicating a superior flavor profile. Colorimetric analysis demonstrated that wild fish maintained vivid reddish pigmentation in the caudal fin (a* = 8.73), whereas farmed fish exhibited marked skin darkening. These findings elucidate a distinct phenotypic and nutritional divergence: intensive farming enhances overall somatic lipid retention, while natural marine environments optimize flavor-active amino acid accumulation and visual appeal, providing critical baseline markers to guide precision aquaculture. Full article

Artemisia annua contains artemisinin, a sesquiterpene lactone endoperoxide; artemether is a semisynthetic derivative of artemisinin that may offer potential advantages due to its redox-modulating and antimicrobial activities. These compounds have been associated with oxidative-stress modulation and microbial inhibition, making them promising candidates for experimental evaluation in nutritional and post-harvest quality studies. This study evaluated the effect of dietary supplementation with A. annua powder, artemisinin, and artemether on the refrigerated quality of Nile tilapia (Oreochromis niloticus) fillets. A total of 160 Nile tilapia were randomly assigned to four treatments: control (no additive), 1% A. annua powder, artemisinin (9.6 mg/kg feed), or artemether (9.6 mg/kg feed). After 30 days of feeding, 320 fillets were collected and stored under refrigeration at 4 °C. Samples were analyzed immediately after slaughter (day 0) and on days 7, 15, and 30. For each treatment group and sampling time, 20 fillets were used: 10 for microbiological evaluations, including counts of mesophilic and psychrotrophic bacteria, molds and yeasts, sulfite-reducing Clostridium, Enterobacteriaceae, coagulase-positive staphylococci, and coliforms; and 10 for physicochemical analyses, including pH, colorimetry, lipid oxidation through TBARS, and sensory evaluation. All supplemented treatments demonstrated improved microbial stability and lower TBARS values when compared with the control. Spoilage indicators such as discoloration, texture loss, and odor deterioration were also delayed. Artemether showed the most pronounced benefits, with lower microbial loads and oxidation indices for several evaluated parameters. These findings suggest that dietary supplementation with A. annua and its derivatives may help delay post-harvest quality deterioration of tilapia fillets during refrigerated storage. Full article

A low matrix effects (MEs) analytical strategy was developed for quantifying diazepam (DZP) in aquatic products by combining immunomagnetic bead (IMB)-based sample pretreatment with UPLC-MS/MS. The preparation conditions of IMBs, sample extraction, and purification were systematically optimized. Due to the weak MEs of this method, the quantification of DZP was carried out using a solvent-based calibration curve with an external standard solution. Good linearity was achieved over the range of 0.5–20 ng/mL with a correlation coefficient (R²) of 0.9971. The LOD and LOQ were 0.125 μg/kg and 0.25 μg/kg, respectively. Recoveries ranged from 85.5% to 106%, with intra-day and inter-day precisions of 1.16–7.04% and 3.42–8.99%, respectively. This work has established a robust, rapid, and practical methodology for DZP residue monitoring in aquatic products. Moreover, it serves as a methodological foundation for the detection of other low-molecular-weight contaminants in complex food matrices, thereby enhancing the surveillance and risk assessment for aquaculture products. Full article

Northern pike (Esox lucius) myofibrillar protein (MP) forms inherently weak gels due to endogenous proteolytic activity and the low thermal stability of fish myosin, limiting its application in surimi products. This study investigated the reinforcing effect and underlying mechanism of rice protein amyloid fibrils (RFs) on pike MP gels. Dynamic rheology revealed that RFs increased both the storage and loss moduli in a concentration-dependent manner, with the 5% group exhibiting an approximately threefold increase in the G′ at 100 rad/s relative to the control. The gel strength, hardness, and chewiness increased progressively with the RF content, whereas the water-holding capacity peaked at 1–3% RFs and declined sharply at 5% RFs. Microstructural imaging showed that moderate RF levels promoted a dense, homogeneous network architecture, while excessive RFs induced phase separation and structural heterogeneity. Hydrophobic interactions and hydrogen bonds were strengthened via RF incorporation, while disulfide bonds decreased monotonically with the increasing fibril concentration. FTIR spectroscopy revealed an α-helix-to-β-sheet transition, with the β-sheet content reaching a maximum of 49.37% at 3% RFs, and SDS-PAGE confirmed that the RF–MP interactions were predominantly non-covalent in nature. These results demonstrate that RFs reinforce pike MP gels through a molecular mechanism involving rigid fibrils acting as structural scaffolds within the protein network and a progressive shift from disulfide-mediated covalent crosslinking toward non-covalent stabilization via hydrophobic interactions and hydrogen bonding. The 1–3% RF range delivers the most balanced gel properties, while excessive fibril loading at 5% induces over-aggregation and impairs water retention. These findings establish amyloid fibrils as effective structural modifiers for freshwater fish gel products and provide a mechanistic basis for their application in surimi processing. Full article

Freshness prediction of starch-coated snakehead fish fillets across different storage times remains challenging due to complex quality deterioration and spectral distribution shifts. In the current research, hyperspectral imaging (HSI) combined with transfer learning (TL) was developed to predict the freshness of starch-coated snakehead fish fillets during short-term refrigerated and long-term frozen storage. The results showed that storage led to texture deterioration, pH increase, TVB-N accumulation, and lipid oxidation, while starch coating effectively delayed quality degradation. Compared with models based only on short-term or long-term data, the domain transfer convolutional neural network (DT-CNN) model improved the robustness of freshness prediction across storage stages. The DT-CNN model based on VIS spectra achieved the best performance for TBA prediction in the starch coating treatment group, with an R_P² of 0.76 and RMSE_P of 0.13, and showed strong performance for TVB-N prediction in the starch coating treatment group, with an R_P² of 0.85 and RMSE_P of 8.66. These results demonstrate that HSI combined with TL is a promising non-destructive method for freshness evaluation of starch-coated snakehead fish fillets during storage. Full article

Off-odor volatiles limit the acceptability of Atlantic salmon. This study investigated the effects of spatial distribution within the fillet, storage conditions, and cooking methods on the volatile profile of salmon and evaluated how pre-harvest rearing conditions, sex, and the presence of skin influence volatile compound formation during storage and cooking. Volatiles were classified as lipid-derived, protein-derived, and environmental contaminants. Spatial distribution within the fillet influenced volatile formation, with the head region exhibiting higher concentrations than the center and tail, reflecting differences in lipid distribution and precursor availability. During storage, fillets stored on ice generally exhibited higher volatile concentrations than samples frozen immediately, particularly for lipid-derived and environmental compounds, consistent with continued biochemical and microbial activity during chilled holding, whereas frozen storage preserved the biochemical state of the fillet. The magnitude of these differences depended on pre-harvest rearing conditions, the presence of skin, and harvest age. Cooking significantly increased volatile concentrations compared to raw fillets, with dry-heat methods, particularly baking, producing the highest levels, while boiling resulted in lower concentrations due to leaching into the cooking medium. Lower volatile formation was generally associated with cool-reared fish, male fillets, and muscle-only samples, while warm-reared, female, and skin-on samples exhibited greater volatile formation or retention, reflecting differences in precursor availability and tissue structure. These findings demonstrate that volatile formation in salmon is governed by the interaction between precursor accumulation during growth, spatial variability within the fillet, and transformation during post-harvest storage and cooking. Full article

Ready-to-eat sea cucumbers (RSC) cannot be preserved at room temperature due to autolysis, which is closely related to the instability of collagen resulting from the disruption of hydrogen bonds. To investigate the protective effect of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) cross-linking against disruption of hydrogen bonds and its role in stabilizing RSC quality at room temperature, this study designed comparative experiments involving EDC/NHS cross-linking treatments with varying sequences of hydrogen bonds disruption. The results indicated that EDC/NHS positively affects the stabilization of the collagen structure in RSC. The various quality parameters of both groups of RSC that underwent cross-linking treatment before and after hydrogen bonds disruption were significantly better than those of the control group, which only experienced the breaking of hydrogen bonds. Notably, the Eb group, which underwent EDC/NHS cross-linking treatment prior to the disruption of the hydrogen bonds network, yielded even more favorable results. Preliminary analyses of textural properties and moisture content suggested that EDC/NHS helps delay the deterioration of RSC quality. The levels of soluble components and carbonyl groups indicated that prior cross-linking treatment is more effective in mitigating collagen degradation and oxidation. Differential scanning calorimetry revealed that the reduction in ΔH for the Eb group was only 2.4%. Furthermore, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and circular dichroism spectroscopy, examined from the perspectives of secondary and tertiary structures respectively, indicated that the cross-linking mechanism of EDC/NHS involves the formation of a more robust network of amide bonds, thereby preventing the disruption of hydrogen bonds and enhancing collagen stability, enabling it to better resist the cleavage of hydrogen bonds due to urea. The scanning electron microscope and Van Gieson’s staining techniques offer a clearer illustration of this point from a microscopic perspective. Moreover, molecular docking simulations have indicated the cross-linking mechanism of EDC/NHS at the atomic level, thereby establishing a scientific foundation for the potential application and development of EDC/NHS in room-temperature storage technologies for RSC. Full article

Climate change is intensifying the release and dispersion of various hazardous chemicals into marine ecosystems, such as algal biotoxins, heavy metals, persistent organic pollutants, and agricultural and industrial wastes. Eutrophication and global warming are responsible for the increase in known and emerging marine biotoxins, such as brevetoxins, palytoxins, pinnatoxins, and cyclic imines. Furthermore, tetrodotoxins and ciguatoxins, which are primarily found in tropical regions, have recently been identified in fish and bivalve molluscs from temperate areas where they had never been previously reported. These toxicants can accumulate in seafood and enter the human food chain, posing a public health concern. This review describes the interrelationship between climate change and its impact on marine organisms and human health, as well as the environment. It recommends integrating a broad range of scientific knowledge, reviewing regulatory policies, and proactively managing public health to counter these environmental threats. Full article

Selenium (Se) speciation in seafood is a key determinant of its nutritional value. However, limited data exist on the influence of common cooking methods on Se chemical forms. This study investigated Se speciation in commonly consumed Thai seafood prepared by different cooking methods, namely, fresh (control), boiling, frying, and grilling, using HPLC–ICP–QQQ–MS. Across all samples, Se was predominantly present in organic forms, with selenomethionine (SeMet) identified as the major species, followed by selenocystine (SeCys₂), while inorganic forms (Se(IV) and Se(VI)) were generally below the limit of quantification. Indo-Pacific horseshoe crab (eggs) consistently presented significantly higher SeMet concentrations than all other seafood species across all cooking methods (p < 0.05). In addition, frying and grilling resulted in higher apparent SeMet concentrations compared to fresh and boiled samples in several species (p < 0.05). This increase should be interpreted as a concentration effect associated with moisture loss during high-temperature cooking, rather than a true chemical formation of SeMet. SeCys₂ concentrations varied across species and cooking conditions, with significantly higher levels found in certain crustaceans, such as banana prawn and musk crab, particularly after boiling (p < 0.05). Extraction yields ranged from 77% to 94%, indicating high analytical recovery. Overall, cooking methods influenced the concentration of Se species but did not substantially alter their chemical forms. These findings suggest that commonly consumed Thai seafood is a rich source of bioavailable Se, particularly in the form of SeMet. Further research is warranted to characterize minor Se species and assess their nutritional implications. Full article

This study evaluated the effects of deheading and intestinal removal on protein degradation and quality changes in chilled Litopenaeus vannamei. The results showed that shrimp subjected to heads removed (HR) and both heads and intestines removed (HIR) maintained better muscle integrity and sensory characteristics compared with intact (CK) and intestines removed (IR) shrimp. Furthermore, the HR and HIR treatments significantly inhibited the accumulation of total volatile basic nitrogen, trichloroacetic acid-soluble peptides, and bitter free amino acids (including His, Lys, Leu, Val, and Tyr), while maintaining consistently low activities of trypsin, cathepsin B, cathepsins B+L, and cathepsin D in the muscle throughout storage. Additionally, intrinsic fluorescence spectroscopy, SDS-PAGE, and microstructural analyses revealed that HR and HIR treatments significantly delayed muscle protein degradation and effectively preserved the structural integrity of muscle tissue. These findings suggest that quality deterioration of shrimp during chilled storage may be largely associated with the migration of endogenous proteases from the hepatopancreas in the cephalothorax into the muscle tissue. Full article

Tilapia fillets are widely popular worldwide, but endogenous foreign matter (such as scales and bones) remaining during processing poses potential risks to quality control and food safety. Furthermore, these endogenous foreign objects are difficult to detect through manual or traditional visual inspection methods. This study developed a non-destructive rapid detection method for endogenous foreign bodies in tilapia fillets. After acquiring high-quality images of foreign bodies using a UV fluorescence imaging system (360–370 nm), a U-Net deep learning model was first employed to accurately segment the foreign body regions. Subsequently, color features were extracted from various color models (RGB, HSV, L*a*b*, and YCbCr), and texture features were extracted from images enhanced by principal component analysis (PCA). A support vector machine (SVM) classifier optimized using a genetic algorithm was then constructed. Among these, the model integrating color and local binary pattern (LBP) texture features (Color-LBP-GASVM) performed well, achieving an average accuracy of 95.9% and an overall average F1 score of 96.15% on the test set. The results confirm that combining UV-induced fluorescence imaging with an integrated deep learning and machine learning framework holds great potential for the automatic and reliable detection of endogenous foreign bodies in tilapia fillets. Full article

The bioaccumulation of cadmium (Cd) in the edible tissues of Oratosquilla oratoria, a seasonal delicacy in Shanghai, poses potential health risks to consumers. This study investigated Cd accumulation in the edible tissues (muscle, gonad, hepatopancreas, intestine, heart) of Oratosquilla oratoria purchased from Shanghai markets, focusing on cadmium content during gonadal development using inductively coupled plasma mass spectrometry (ICP-MS). Results revealed the hepatopancreas as the primary site of Cd storage, with concentrations in the intestine and hepatopancreas (10.64–58.27 mg/kg) being orders of magnitude higher than those in the gonads and muscle (0.01–0.48 mg/kg). Strikingly, Cd levels in the gonads remained consistently low throughout development and did not correlate with the gonadosomatic index. This indicates a biological barrier that sequesters Cd in the outer gonad membrane of Oratosquilla oratoria, thereby protecting germ cells from toxicity. Health risk assessment indicated that consumption of the intestine and hepatopancreas poses a potential carcinogenic risk, whereas the most commonly consumed tissues—muscle and gonads—present a low risk. Our findings clarify the differential bioaccumulation of Cd in Oratosquilla oratoria, reveal a potential biological mechanism for gonadal protection, and provide a scientific basis for targeted consumption guidance to mitigate public health risks. Full article

South China carp (Cyprinus carpio rubrofuscus) with low bone mineral density (BMD), characterized by softened bones and wavy ribs, were identified during paddy field aquaculture. This study investigated the association between bone status and muscle traits by comparing muscle texture, nutritional composition, histology, ultrastructure, and proteomic profiles between low-BMD fish (BMD-low, ≤0.02 g/cm²) and normal-BMD fish (BMD-normal, ≥0.04 g/cm²). Compared with the BMD-normal group, the BMD-low group showed significantly lower muscle resilience and chewiness, significantly higher iron content, and significantly lower methionine and histidine contents (p < 0.05). Histological analysis revealed increased muscle fiber density, reduced muscle fiber cross-sectional area, and greater intramuscular lipid accumulation in the BMD-low group (p < 0.05). Ultrastructural observations further showed myofibrillar disorganization and elongated sarcomeres and A-bands (p < 0.05). Proteomic analysis identified 21 differentially expressed proteins, including up-regulated desmin a and down-regulated nebulin. KEGG enrichment indicated that these proteins were mainly involved in the cytoskeleton in muscle cells, calcium signaling, regulation of actin cytoskeleton, and ubiquitin-mediated proteolysis. These findings provide new insights into the relationship between bone status and muscle quality in South China carp and support future quality evaluation and selective breeding. Full article