Assessment of biogenic amines in commercial tuna fish: Influence of species, capture method, and processing on quality and safety

This study investigated the influence of species, capture method, chilling, and freezing on the quality and variations in biogenic amines of Thunnus tonggol and Thunnus albacares. Samples were collected from different sources, including fisheries ports, cold rooms, and canning factories. The results indicated that canned fish had significantly higher levels of biogenic amines, especially histamine, compared to raw fish from ports and cold rooms. However, all canned samples complied with the FDA regulation of 50 mg/kg for histamine content. Canning led to a substantial increase in total amines, with histamine being the predominant amine in most groups. Putrescine was present in all samples, with the highest levels found in canned tuna made from frozen yellow-fin tuna captured using drift gillnetting. Canned samples also exhibited higher cadaverine levels compared to raw tuna. Storage conditions, capture method, and tuna species were found to significantly affect tuna quality and biogenic amines formation.

The concentration and health risk assessment of radionuclides in the muscle of tuna fish: A worldwide systematic review and meta-analysis

Exposure to radionuclides, especially in food, can endanger the health of consumers. In this study, a systematic review and meta-analysis were performed regarding the concentration of radionuclides in tuna fish muscle. International databases including PubMed, Scopus, and Embase were searched to find articles regarding the concentration of radionuclides in tuna fish muscle from 1 January 2000 to 20 February 2021. The lowest and highest concentration of radionuclides was related to Caesium-137 (¹³⁷Cs) and Potassium-40 (⁴ K), respectively. The rank order of radionuclides based on their pooled concentration was ⁴ K (370.157 Bq/kg) > ²¹⁰Po Polonium-210 (26.312 Bq/kg) > ²¹⁰Pb (5.339 Bq/kg) > ²²⁶Ra (4.005 Bq/kg) > ¹³⁷Cs (0.415 Bq/kg). The health risk assessment based on annual effective dose indicates that consumers are at the safe range of health risk (H < 1 mSv/y). The continuous monitoring concentration of radionuclides in seafood and health risk assessment should be recommended.

Rapid and Low Cost Determination of Total Mercury in Cat Foods by Photochemical Vapor Generation Coupled to Atomic Absorption Spectrometry

A rapid and low-cost method for determination of total mercury (THg) in cat food was developed based on photochemical vapor generation (PVG) coupled to cold vapor atomic absorption spectrometry (CVAAS). Cat food samples with ingredients based on tuna fish and other seafood were investigated. Organic acid precursor and concentration for radical generation and Hg photoreduction, sample UV irradiation time, and carrier gas flow were optimized. Highest PVG efficiency was achieved using 10% v v^-1 formic acid, 4-s UV irradiation time, and a carrier gas flow of 50 mL min^-1. The calibration function presented a correlation coefficient of 0.99. Accuracy was confirmed by analysis of Certified Reference Materials with recoveries of 93-110% and relative standard deviation lower than 6%. Under optimized conditions, a procedural detection limit of 0.28 μg kg^-1 was obtained. Determination of THg in 10 samples of cat food purchased in local markets revealed a concentration range of 0.035-0.388 mg kg^-1. Highest concentrations were found in cat foods. Only one sample presented a concentration close to the regulatory limit of the European Commission Directive. Assuming the estimated daily food intake (EDI) calculated in a range of 0.0021 to 0.023 mg of THg per day per kg body weight, it is concluded that it remains below that considered lethal for cats. The methodology is efficient, simple, low cost, and fit for purpose.

A novel highly efficient and ultrasensitive electrochemical detection of toxic mercury (II) ions in canned tuna fish and tap water based on a copper metal-organic framework

Invisible mercury ion is an incredibly toxic pollutant to the atmosphere. Thus a quick and sensitive detection method is of considerable importance for toxicological assessment, environmental protection and human health. A novel electrochemical sensing system has been developed for the detection of mercury (Hg²⁺) ions in canned tuna fish and tap water. The sensing platform was developed on the cubic copper-metal-organic framework (Cu-MOF) based nanoparticles. Cu-MOF has a porous architecture with a large, unique surface area that is favorable for mercury ions adsorption and preconcentration. The electrochemical properties of Cu-MOF nanoparticles modified electrode were investigated. Differential pulse voltammetry (DPV) and cyclic voltammetry (CV) were applied for the detection of mercury in 0.1 M phosphate buffer (PB) at pH 9 under ambient conditions. Under optimized conditions, the limit of detection (LOD) for Hg²⁺ is around 0.0633 nM with a linear range of 0.1-50 nM. Cu-MOF nanoparticles were successfully applied to the analysis of mercury ions in canned tuna fish and tap water. The developed sensor demonstrated satisfactory anti-interference, reproducibility, reliability, repeatability and applicability for the detection of mercury ions. This proof of principle serves as a steppingstone towards promoting ultrasensitive and precise assay for the detection of mercury.

A sonochemical assisted synthesis of hollow sphere structured tin (IV) oxide on graphene oxide sheets for the low-level detection of environmental pollutant mercury in biological samples and foodstuffs

In modern approaches for nanomaterials synthesis, ultrasonication plays an important role in providing the larger surface area and smaller crystalline size properties that are favorable to electrochemical techniques. Herein, we report the tin (IV) oxide on graphene oxide nanoparticles were synthesized (SnO₂@GO NPs) by ultrasonic methodology (UZ SONOPULS HD 3400 Ultrasonic homogenizer) with the total power of 400 W and the (frequency of 20 kHz; 140 W/dm³). The formation of as-prepared SnO₂@GO NPs and its surface morphology were scrutinized over XRD, XPS, TEM, and FESEM. Besides, the sonochemically prepared SnO₂@GO NPs were employed for the determination of environmental hazardous mercury (Hg). As a result, the modified electrode acquired a very low-level detection limit of 1.2 nM with a wider range of 0.01-10.41-µM and 14.52-225.4-µM for the detection of Hg. Finally, the practical applicability of SnO₂@GO NPs in spiked human blood serum and tuna fish samples shows appreciable found and recovery values. .

The applications of Lactobacillus plantarum-derived extracellular vesicles as a novel natural antibacterial agent for improving quality and safety in tuna fish

Bacteria release membrane vesicles into the extracellular environment but which activity is unclear. We investigated the applications of extracellular vesicles (EVs) isolated from probiotic Lactobacillus plantarum to protect tuna fish against spoilage and quality loss in this study. A significant difference was found in EVs size obtained from L. plantarum after 8, 24, and 48 hr incubation. The L. plantarum-derived EVs were collected and used to confirm the anti-bacterial activity versus Shewanella putrefaciens. Finally, the tuna fish was stored at 4 °C for 5 days after coating with EVs or sodium erythorbate, and the quality indexes were assayed. Results indicated that EVs markedly inhibited oxidation reaction, total volatile base nitrogen (TVBN), peroxide value (PV), malondialdehyde (MDA), and bacteria levels. These results finding out that EVs from L. plantarum may have potential for application in food storage technology. Overall, we indicated this new material may be developed as an anti-bacterial agent for prolonging the shelf life of tuna fish.

Human health risk assessment of heavy metals via consumption of commercial marine fish (Thunnus albacares, Euthynnus affinis, and Katsuwonus pelamis) in Oman Sea

This study was performed to determine the concentrations of copper (Cu), zinc (Zn), and lead (Pb) in the gill, liver, muscle, and tail fin tissues of Euthynnus affinis, Katsuwonus pelamis, and Thunnus albacares from Oman Sea. All samples were analyzed using a flame atomic absorption spectrophotometer and the results were expressed as μg g^-1 dry weight. Metal concentrations were significantly higher in the liver than other tissues in three species (with some exceptions) (p < 0.05). The concentrations of metal accumulation in tissues of tuna species followed the Zn > Cu > Pb. Correlation matrix and principal component analysis (PCA) revealed that Zn and Pb have anthropogenic sources. Estimated daily intake (EDI) in three tuna species for heavy metals were below the tolerable daily intake (TDI). Also, the mean target hazard quotient (THQ) based on studied metals in three tuna species was below 1, which suggests that consumption of these fish can be safe for human health in the Oman Sea. Graphical Abstract .

Effect of immersion ohmic heating on thawing rate and properties of frozen tuna fish

In the present study, the application of immersion ohmic heating was examined to improve thawing of frozen tuna fish cubes. The experimental tuna cubes (3 × 3 × 3 cm³) were thawed under ohmic heating subjected to three different voltages (40, 50, and 60 V) with three different concentrations (0.3, 0.4, and 0.5% w/v) of brine solution. The parameters associated with the quality of tuna, such as thawing time, thawing rate, thawing loss, cooking and total losses, centrifugal loss, lipid oxidation, texture, and color, were investigated during ohmic heating thawing, and compared with the conventional still air thawing, water thawing at 27 and 40 ℃. The results showed that immersion ohmic thawing significantly decreased the thawing time of frozen tuna fish cubes. Thawing time in ohmic treatment (50 V- 0.3% brine) was 5.95 times shorter than conventional conditions. The lowest thawing and cooking losses were observed at ohmic treatments. In addition, the ohmic treatments (group 1) were evaluated versus conventional methods (group 2) and the results showed that thawing and total losses in group 1 were significantly lower than group 2.

Japans commercial whaling is a threat to public health

Japans' decision to withdraw from the International Whaling Commission and reinstate commercial hunting on minke, sei and Bryde's whales has recently been discussed in several journals. Here we discuss mercury exposure to the public eating baleen whales, toothed whales and tuna in relation to the European Food Safety Authority (EFSA) tolerable weekly intake (TWI).

Carbon Monoxide Residues in Vacuum-Packed Yellowfin Tuna Loins (Thunnus Albacares)

The use of carbon monoxide (CO) in fresh fish has generated considerable debate. Carbon monoxide is used to treat fresh fish in order to retain its fresh red appearance for a longer period. It reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex that may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish (Thunnus Albacares) has been investigated by means of optical spectroscopy. Formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. Samples were judged as CO treated when their levels were higher than 200 ng/g. Only two positive samples out of 29 analyzed were detected. The high level of uncertainty (0.30) of the method requires the use of more specific and sensitive methods for confirmatory analysis.

Bacteriological Quality of Tuna Fish ( Thunnus thynnus ) Destined for Canning: Effect of Tuna Handling on Presence of Histidine Decarboxylase Bacteria and Histamine Level

The present paper analyzes the bacteriological quality and histamine content of tuna fish samples destined for canning. Raw material used in the canning process was of good quality. Histamine-producing bacteria counts were only found in three samples from the last step of the canning process before sterilization. Most of the bacteria identified as histamine formers were gram negative, and nearly all of which belonged to the Enterobacteriaceae family. Morganella morganii was the most frequent and active histamine former in tuna fish destined for canning. Other powerful histamine-producing bacteria isolated during the canning operation were Klebsiella oxytoca , Klebsiella pneumoniae and some strains of Enterobacter cloacae and Enterobacter aerogenes . They all were able to produce more than 500 ppm of histamine in experimental conditions. Most of these species might be expected to be found as a result of contamination of fish during capture and subsequent unhygienic handling in the canning plant. An increase in histamine content in tuna meat was not expected through the canning process. Histamine content always was acceptable in accordance with the maximum allowable levels of histamine fixed by both the European Economic Community and Food and Drug Administration.