Search Results (35)

Canning is an excellent solution to provide convenient, affordable, nutritious, and safe seafood with a long shelf life. However, many canned products use tuna, sardines, and Atlantic chub mackerel, species that raise sustainability concerns and whose overuse can put additional pressure on them. Hence, this study aimed to i) develop and assess a nutritious and sustainable canned meal prototype using the Atlantic horse mackerel (Trachurus trachurus) (whose EU allowable-catch amounts have increased, particularly, in Iberian waters) and vegetables in light brine in terms of stability, sterility, and physicochemical and sensory properties over a 4-month period at room temperature and ii) evaluate its nutritional contribution for different population groups. After preparation, the meal was stored for one month at ≈20 °C and ≈40 °C (to simulate the 4 months). Although the pH was not stable, the meal was considered commercially sterile according to the challenge accelerated tests. Moreover, aging did not significantly affect the meal’s physicochemical and sensory properties. This innovative meal prototype can be claimed to be “low-fat”, “reduced in NaCl/Na”, a “source of protein, phosphorus, iron, selenium and vitamin D”, and “high in vitamin B12”. It proved to be both nutritious and appealing for consumption, with potential to be scaled up. Full article

Background/Objectives: Improving one’s diet for the purpose of promoting health is constrained by people’s ingrained eating habits, as the eating patterns that align with their established habits do not necessarily correspond to a healthy way of eating. In addressing the issue of improving diet while taking both health and habits into consideration, this paper focuses on three concepts of complementarity related to food combinations and presents an approach using Japanese data. Methods: This paper first organizes three concepts of complementarity related to food combinations. The three concepts of complementarity are formulated based on (i) nutrients, (ii) habits, and (iii) recipes. The definitions of measurement scales corresponding to these concepts are also discussed. Results: Using data from a specific region in Japan, we analyzed three types of complementarities related to food combinations across different gender and age groups. This approach enabled us to visualize the potential for dietary improvements and identify effective strategies tailored to each group. For instance, among females aged 50 and above in this region, it was found that recipes incorporating combinations such as (α) milk and pasta, (β) salmon and pasta, (γ) horse mackerel or sardines with carrots, and (δ) onions with taro can efficiently support dietary improvement for this demographic, building upon their established dietary habits. The differences in recommended recipes for each group are due to variations in nutrients that tend to be insufficient and differences in established eating habits. Conclusions: A combination of foods with high (i) complementarity of nutrients constitutes a healthy diet, whereas a combination of foods with low (ii) complementarity in habits reflects dietary behaviors that are not sufficiently practiced within the relevant sub-population at present. Meanwhile, combinations of foods with high (iii) complementarity in recipes can serve as tools to bridge the gap between healthy eating patterns and established dietary habits. Full article

Background: Red macroalgal flour resulting from commercial phycocolloid extraction has been shown to include valuable preservative compounds. Methods: This study focused on the preservative effect of a gelatin-based packaging system including Gelidium sp. flour during refrigerated storage of Trachurus trachurus fillets. Different microbial and chemical indices related to quality loss were determined in fish muscle during a 6-day storage period at 4 °C. Results: Compared with gelatin-packaged control samples, those packaged in the system including the algal flour presented significantly lower microbial development (aerobic bacteria, psychrotrophic bacteria, and proteolytic bacteria) and significantly lower chemical indices related to microbial development (pH and trimethylamine). With respect to lipid oxidation, there was significantly greater retention of peroxides and significantly lower formation of secondary oxidation products in the samples packaged with the algal flour. Additionally, the algal flour group presented significantly less lipid hydrolysis. Conclusions: A preservative effect was derived from the addition of Gelidium flour to a gelatin-based packaging system during refrigerated storage of T. trachurus. This study supports the practical and valuable use of Gelidium sp. flour and addresses the current global interest in natural sources of preservative compounds and the use of marine byproducts. Full article

The expansion of fisheries and aquaculture in recent decades has led to a substantial increase in fish by-products. This study investigates the extraction and characterization of calcium phosphates from the by-products of representative species in these industries, aiming to identify potential sources for biotechnological and pharmaceutical applications. Clean bones obtained by enzyme hydrolysis from the heads, central skeletons, and/or tails of Atlantic horse mackerel, blue whiting, hake, mackerel, and farmed turbot were subjected to calcination to obtain calcium phosphates. The clean bone content in terms of nitrogen, lipids, organic matter, total protein, and amino acids was evaluated together with the chemical bonds, structures, and elemental composition of calcium phosphates. Results indicated a significantly higher yield of wet bone recovery (23%, p < 0.05) for the central skeleton of Atlantic horse mackerel and the highest mineral fraction for the heads of Atlantic horse mackerel (73.2%), followed by that of blue whiting (72.6%). Hake and turbot presented the lowest mineral fractions and, therefore, the highest protein content (27–31%, p < 0.05), with significant levels of collagen-related amino acids (p < 0.05). X-ray diffraction (XRD) and Fourier-transform Raman spectroscopy (FT-Raman) confirmed the biphasic calcium phosphate composition for most samples based on hydroxyapatite with contributions of whitlockite/β-tricalcium phosphate. The highest contribution to the non-apatite phase was made by the central skeletons of both mackerel and Atlantic horse mackerel. Full article

This study analysed commercial ‘Srdelara’ purse seine landings in the Central Eastern Adriatic from November 2020 to March 2022. The observed commercial landings demonstrated typical seasonal variations, with a peak from September to November and the lowest landings recorded from spring to early summer. Sardines dominated the purse seine landings, comprising 97.9% of the total landing, followed by anchovies at 1.3%, with occasional by-catches or other species. Biological analysis involved collecting samples of eight pelagic fish species (sardine, anchovy, round sardinella, Atlantic bonito, Atlantic horse mackerel, Atlantic mackerel, chub mackerel and bogue) captured by the aforementioned fishing gear during the study period. The length frequency distributions of the investigated fish species were predominantly unimodal, with the exception of the Atlantic horse mackerel. Moreover, the length–weight relationships indicated isometric growth for each examined species. Stable isotope analysis revealed overlapping isotopic niches among the eight analysed fish species, with estimated mean trophic positions ranging from 3.0 to 4.7, indicating consumption of prey across approximately two trophic levels. The round sardinella and bogue had the smallest isotopic niche, while Atlantic mackerel had the widest one. This study highlights the need for further research to evaluate the observed overlap among pelagic species, particularly between small and medium-sized pelagic fish, as this interaction could significantly impact their biomass. Determining the extent of this overlap is crucial for improving management strategies and ensuring the sustainability of pelagic fish stocks in the Adriatic Sea. Full article

Frequent intentional mislabeling of particular fish and fish products, such as the sale of frozen and thawed fish instead of fresh fish, occurs on all continents. Therefore, two studies were conducted to classify fish meat using excitation–emission matrix (EEM) nondestructively. The first study assessed EEM for differentiation between fresh and frozen–thawed spotted mackerel fillets. Fresh fillets were yielded with different post-mortem freshness variations (ice storage for 0–40 h). The right-side fillets were used as fresh fillets, whereas the left-side fillets were frozen and stored at −30 °C for three months, then thawed at 4 °C. Subsequently, EEM acquisition and chemical analyses were performed. Results of principal component analysis (PCA) of EEM spectra showed clear discrimination between fresh and frozen–thawed meat of fish fillet. In the second study, post-mortem freshness variations in four fish species (horse mackerel, spotted mackerel, cod, and flounder) were simulated by ice storage (0–48 h) and subsequent freezing. PCA of the EEM demonstrated a clear distinction among the fish meat categories, which was also revealed from the freshness data of chemical analysis. Results show that this novel method can be used to monitor fishery product authenticity. Full article

The aim of this study was to investigate the preservative properties of alga Gelidium sp. flour when included in the glazing medium employed for the frozen storage (−18 °C) of horse mackerel (Trachurus trachurus). Different concentrations (low, medium, and high) of an aqueous extract were tested and compared to a control water-glazing condition. Quality changes (lipid oxidation and hydrolysis, fatty acid (FA) profile, and trimethylamine (TMA) formation) were determined after 3- and 6-month storage periods. A general quality loss (lipid oxidation with hydrolysis development and TMA formation) with the frozen storage period was detected in all samples. The presence of an alga flour (AF) extract in the glazing medium led to a lower (p < 0.05) TBARS and fluorescent compound formation and to higher (p < 0.05) polyene values in frozen fish. Furthermore, a preserving effect on free fatty acids was detected in AF-treated fish. On the contrary, the AF-glazing treatment did not affect (p > 0.05) the TMA formation and the total n3/total n6 FA ratio. In general, preservative effects were found to be higher in frozen fish corresponding to the medium concentration tested. Current results show the potential of Gelidium sp. flour as a natural source of preservative hydrophilic compounds for the quality enhancement of frozen horse mackerel. Full article

In contemporary markets, fish are frequently wrapped in cling film, necessitating consumers’ reliance on visual cues to assess freshness. This study explores whether common Japanese consumers can accurately discern fish freshness based solely on visual information. We conducted an online experiment with 529 randomly selected participants in Japan by asking them to select the freshest fish from photographs of horse mackerel with varying freshness levels. In order to elucidate the mechanism of freshness detection, we conducted principal component analysis on the quantified body color and shape data. Additionally, we measured physical characteristics such as lipid contents, gloss, length, and weight of the fish. This study examines the correlation between these visual cues and consumers’ judgments, revealing the accuracy of visual indicators used by consumers in daily assessments of fish freshness. These findings suggest that a portion of Japanese consumers can correctly identify the freshness of fish based on appearance. They primarily rely on the brightness of the fish’s eyes and specific color combinations of the body to judge freshness, with the shape of the fish having less impact. Comparing the selection frequency between high- and low-accuracy participants, we observed that a low accuracy in freshness detection was not solely due to a lack of sensitivity to signals from photographs, but may also result from a misinterpretation of these signals by consumers. Full article

In this study, the distribution patterns of southern horse mackerel are examined using commercial fine-scale resolution data. Using landings by size category and VMS data from the Portuguese commercial bottom-trawl fishery, which consistently targets horse mackerel, this study provides a comprehensive analysis of horse mackerel age distributions spanning a decade (2010–2020). Importantly, this study addresses potential biases in commercial effort data and establishes the usefulness of commercial bottom-trawl gear as a suitable method for sampling and evaluating southern horse mackerel stock dynamics. Ordered regression models were applied to allow for the modelling of the distribution of multiple age categories and investigate spatio-temporal migrations off the Portuguese coast. Southern horse mackerel show a widespread age distribution range and stable abundance with indications of seasonal and spatial patterns in the distribution of specific age groups. The insights derived from this research contribute valuable knowledge for understanding the dynamics and distribution patterns of fish populations. Full article

The combined effects of thermal processing (i.e., sterilisation treatment) and the prior frozen storage time (3 or 6 months at −18 °C) on the quality loss in canned Atlantic horse mackerel (Trachurus trachurus) were determined. Thus, the sterilisation step led to a remarkable (p < 0.05) formation in the canned fish muscle of fluorescent compounds, free fatty acids (FFAs), and trimethylamine and an increase in the L* and b* colour parameters; meanwhile, a decrease (p < 0.05) in the total ω3 FA/total ω6 FA ratio and the a* colour value were detected. The prior frozen storage period led to an increased (p < 0.05) lipid oxidation (peroxide, thiobarbituric acid reactive substance, and fluorescent compound formation) and hydrolysis (FFA formation) development and to increased L* and b* colour values in the corresponding canned samples; additionally, a lower (p < 0.05) polyene index and phospholipid content were observed in canned fish previously subjected to frozen storage. In most indices, physico-chemical changes related to quality loss were found to be higher if the previous storage period was increased. According to the marked effects of the sterilisation step and the prior frozen storage period, the optimisation of such processing conditions is recommended to maximise the quality of canned horse mackerel. Full article

This work creates a fish species identification tool combining a low-cost, custom-made multispectral camera called MultiCam and a trained classification algorithm for application in the fishing industry. The objective is to assess, non-destructively and using reflectance spectroscopy, the possibility of classifying the spectra of small fish neighborhoods instead of the whole fish for situations where fish are not completely visible, and use the classification to estimate the percentage of each fish species captured. To the best of the authors’ knowledge, this is the first work to study this possibility. The multispectral imaging device records images from 10 horse mackerel, 10 Atlantic mackerel, and 30 sardines, the three most abundant fish species in Portugal. This results in 48,741 spectra of 5 × 5 pixel regions for analysis. The recording occurs in twelve wavelength bands from 390 nm to 970 nm. The bands correspond to filters with the peculiarity of being highpass to keep the camera cost low. Using a Teflon tape white reference is also relevant to control the overall cost. The tested machine learning algorithms are k-nearest neighbors, multilayer perceptrons, and support vector machines. In general, the results are better than random guessing. The best classification comes from support vector machines, with a balanced accuracy of 63.8%. The use of Teflon does not seem to be detrimental to this result. It seems possible to obtain an equivalent accuracy with ten cameras instead of twelve. Full article

The antioxidant properties of the liquor resulting from commercial octopus cooking were analysed for this study. Two different concentrations of octopus-cooking liquor (OCL) were tested as glazing systems during the frozen storage period (−18 °C for up to 6 months) of whole Atlantic horse mackerel (Trachurus trachurus). Compared to water-control glazing samples, an inhibitory effect (p < 0.05) on lipid oxidation development (the formation of thiobarbituric acid reactive substances and fluorescent compounds) was detected in frozen fish treated with the most concentrated OCL-glazing system. Additionally, a preservative effect (p < 0.05) on polyunsaturated fatty acids (measurement of polyene index) was also proved. However, no effect (p > 0.05) on the free fatty acid content and on the ω3/ω6 ratio was detected with the presence of the OCL in the glazing system. An increased lipid quality in frozen horse mackerel was established by including the OCL solution in the glazing system. According to previous research, the observed preserving properties were explained on the basis of the presence of antioxidant compounds in the cooking liquor. A novel and valuable combination of glazing processing and the employment of a marine waste substrate is proposed to enhance the lipid stability of frozen fish. Full article

People spend most of their time indoors, particularly in their houses where daily activities are carried out, enhancing particulate matter (PM) emissions with consequent adverse health impacts. This study intended to appraise the toxicological and mutagenic responses of particulate matter with a diameter less than 10 μm (PM₁₀) released from cooking and ironing activities under different conditions. The cytotoxicity of the PM₁₀ total organic extracts was tested in A549 cells using the WST-8 and the lactate dehydrogenase (LDH) assays, while the interference in cell cycle dynamics and reactive oxygen species (ROS) production was analysed by flow cytometry. The S. typhimurium TA98 and TA100 Ames tester strains with and without metabolic activation were employed to determine the mutagenic potential of the PM₁₀-bound polycyclic aromatic hydrocarbons (PAHs). PM₁₀ organic extracts decreased the metabolic activity of A549 cells; however, no effects in the LDH release were observed. An increase in ROS levels was registered only for cells treated with PM₁₀ at IC₂₀ from steam ironing, in low ventilation conditions, while cell cycle dynamics was only affected by exposure to PM₁₀ at IC₂₀ from frying horse mackerel and grilling boneless pork strips. No mutagenic effects were observed for all the PM₁₀-bound PAHs samples. Full article

The Mediterranean is one of the most overfished seas of the world where mesopredators are severely threatened. The trophic strategies of four pelagic species that inhabit the Adriatic Sea (Scomber spp. and Trachurus spp.) were investigated through an integrated approach of stomach contents and stable isotopes analyses. Our study demonstrated that Scomber colias feeds mainly on strictly pelagic prey, with fish larvae as a secondary prey in the Southern Adriatic Sea, while S. scombrus feeds on prey belonging to higher trophic levels. Smaller specimens of Trachurus mediterraneus have a diet mainly based on pelagic prey, while larger fishes rely on prey such as benthic decapods, showing an ontogenetic shift in the diet of the species. Trachurus trachurus shows a preference for offshore and deeper areas and a diet such as that of its congeneric, but no clear ontogenetic shift was observed. This spatial segregation allows the co-existence of these two species of Trachurus. Scomber colias mainly inhabits southern areas and S. scombrus shows a preference for the northern sectors. This latitudinal gradient avoids the overlap of their trophic niches. Bayesian mixing models confirmed that the trophic niches of these species only partially overlap in the middle of the trophic web. Full article

Abundance indices are essential data for the application of stock assessment models to obtain fish abundance estimates. Abundance indices have usually been derived from fishery-dependent data, yet the increase in fisheries-independent surveys is now offering new opportunities for these calculations. In this study, we explored the usefulness of ichthyoplankton indices derived from scientific surveys in estimating spawning biomass. In addition, we also investigated whether the strength of the year–class of the commercial cohort of Atlantic hake, as a determinant, could be defined at an early life stage. We used samples collected during the triennial mackerel and horse mackerel egg surveys (MEGS), which cover the hake spawning area in the Bay of Biscay. The biomass indices were determined as the abundance of eggs in the early development stage (stage 1) when transformed into egg production (EP) from 1995 to 2019 in the months of March and April—which is considered a period of high spawning activity for hake in this area. Additionally, we built a metric for larval abundance and converted larval length into age. This was in addition to constructing a pre-recruit year-class index (YCI) while using the EVHOE bottom trawl abundance database for hake for the period of 1997 to 2016. The results of regression analysis of egg production and spawning stock biomass indicate that both parameters are significantly correlated (r = 0.76). By connecting the abundance of eggs and larvae in the adjoining stages, we are able to identify two periods of high mortality associated with the transition from “yolk-sac-first” to “feeding larvae” and “late larvae-YCI10”, but we were unable to discover when the strength of the recruitment year–class is determined. As such, it appears that for the northern stock of hake, recruitment is established in the late juvenile stages. Full article