Effect of partial sodium replacement on physicochemical parameters of smoked sea bass during storage

Integration of untargeted lipidomics and targeted metabolomics revealed the mechanism of flavor formation in lightly cured sea bass driven via salt

Salt enhances flavor and salinity in Chinese curing; however, excessive use can pose health risks, while reducing NaCl may harm taste. This study utilized targeted and untargeted metabolomics to investigate the intrinsic molecular mechanisms that drive flavor formation in cured sea bass subjected to salt. Glycine, succinic acid, lactic acid and uridine significantly contributed to the taste profile of the cured sea bass. A total of 668 lipid molecules were annotated in the samples, of which 60 were classified as differential lipids. Non-targeted lipidomic analysis identified phosphatidylcholine and phosphatidylethanolamine as the major flavor precursors, constituting 40.12 % of the total. Elevated salt concentrations significantly enhanced the production and accumulation of key differential volatile flavor components, including 1-octen-3-ol, 2-undecanone and 2-pentylfuran. Thus, salt facilitated the degradation and oxidation of lipids, leading to the formation of key flavor compounds that contribute to the enhancement of the flavor profile of cured sea bass.

The revealing of the Cyto-genotoxic properties (Allium and MTT) and the effect of chicken meat quality of characterized zein-eugenol nanofibers

Electrospun zein-based eugenol nanofibers (ZEnF) with diameters (148.19-631.52 nm) were fabricated. Thermal degradation was found as <15 % until 300 °C while the nanofiber diffraction pattern presented three main peaks among the 5o and 45o positions. ZEnF was not only evaluated as non-toxic to cells but also possessed anticancer characteristics revealing with the MCF-7 cell line at 800 μg/mL (reduction: 18.08 %) and 1600 μg/mL (reduction: 41.64 %). Allium tests revealed that ZEnF did not have any adverse impact on the health status (chromosomes-DNA) of exposed organisms. Following the nanofiber coating for chicken meat parts (thigh and breast), it was observed up to 1.25 log CFU/g limitation in total viable bacteria counts (p < 0.05). The sensory score (difference: 3.64 in 10 points scoring on the 6th day of the cold storage) and odor score of chicken meat samples were found to be as higher than control samples (p < 0.05).

Effects of umami substances as taste enhancers on salt reduction in meat products: A review

Sodium is one of the essential additives in meat processing, but excessive sodium intake may increase risk of hypertension and cardiovascular disease. However, reducing salt content while preserving its preservative effect, organoleptic properties, and technological characteristics poses challenges. In this review, the mechanism of salt reduction of umami substances was introduced from the perspective of gustation-taste interaction, and the effects of the addition of traditional umami substances (amino acids, nucleotides, organic acids(OAs)) and natural umami ingredients (mushrooms, seaweeds, tomatoes, soybeans, tea, grains) on the sensory properties of the meat with reduced-salt contents were summarized. In addition, the impacts of taste enhancers on eating quality (color, sensory, textural characteristics, and water-holding capacity (WHC)), and processing quality (lipid oxidation, pH) of meat products (MP) and their related mechanisms were also discussed. Among them, natural umami ingredients exhibit distinct advantages over traditional umami substances in terms of enhancing quality and nutritional value. On the basis of salt reduction, natural umami ingredients improve the flavor, texture, WHC and antioxidant capacity. This comprehensive review may provide the food industry with a theoretical foundation for mitigating salt consumption through the utilization of umami substances and natural ingredients.

Utilization of Yeast Extract as a Flavor Enhancer and Masking Agent in Sodium-Reduced Marinated Shrimp

Deepwater pink shrimp (Parapenaus longirostris) has a significantly high catch yield and is a highly important food source for human nutrition in terms of its nutritional value. The reduction of salt content in seafood products while preserving taste poses a significant challenge. The aim of this study is to reduce the NaCl ratio used in the shrimp marination process by substituting it with KCl and masking the resulting bitterness from KCl using natural flavor enhancers, such as yeast extracts. The marinated shrimp were prepared using 50% KCl instead of 50% NaCl. In order to mask the bitter taste caused by KCl and enhance the flavor, two different types of yeast extracts obtained from Saccharomyces cerevisiae were utilized in the formulation. Nutritional composition, Na and K contents, amino acid composition, color measurement, bacteriological quality, pH changes, and sensory evaluations were conducted to assess the impact of salt reduction and yeast extracts on the sensory, chemical, and physical attributes of the products. L-glutamic acid, L-alanine, L-aspartic acid, L-leucine, L-valine, and L-lysine were found to be higher in samples with Levex Terra yeast extract. Despite a 50% reduction in NaCl content, the addition of yeast extract led to an increase in the umami taste due to the elevation of amino acids present. Yeast extracts can offer a promising solution for enhancing the sensory qualities of seafood products with reduced salt content by conducting more detailed sensory development examinations.

Investigations of the Polycyclic Aromatic Hydrocarbon and Elemental Profile of Smoked Fish

Fish are vulnerable to environmental pollutants such as polycyclic aromatic hydrocarbon and heavy metals. As one of the most commonly applied processing methods, the smoking of different species has been applied globally. Hence, this study aims to investigate the smoking process on the polycyclic aromatic hydrocarbon and elemental accumulation of the five different species (rainbow trout, Atlantic bonito, horse mackerel, sea bass, and Atlantic bluefin tuna) which are commonly processed and traded in the smoked fish industry. The processing yield, water holding capacity, and pH were also investigated. The results revealed that the proximal differences among fish species influence the water holding capacity, processing yield, and pH which are very important for process sustainability and the quality of the end product. The main finding was the proximal composition impact on the accumulation of both PAHs and heavy metals at different levels. While all of the tested samples were below the maximum permissible limit, some of the heavy metals, especially toxic elements, were found above the acceptable limit. Horse mackerel is determined to be the species most vulnerable to PAHs and heavy metal accumulation.

The Development of Smoked Mackerel with Reduced Sodium Content

The World Health Organization recommends reducing salt (sodium chloride, NaCl) intake by 30% by 2025. Since smoked fish can deliver up to 4 g NaCl/100 g, the aim of this study was to develop safe, healthy and attractive smoked chub mackerel (Scomber japonicus) with a reduced NaCl content. Two brines (5% and 10%) were used with different ratios of NaCl and potassium chloride (KCl). In each brine, 0%, 25%, 50% and 75% of NaCl was replaced by KCl, resulting in 1.3, 1.1, 0.9 and 0.6 g NaCl (5% brine), and 2.6, 2.0, 1.2 and 0.8 g NaCl (10% brine) per 100 g, respectively. Similar yield, nutritional, safety, texture and colour properties were found in most formulations. The most desirable taste attributes (negligible bitterness and adequate saltiness) were obtained with a 5% brine prepared with 75% NaCl + 25% KCl. Such conditions seemed to allow for obtaining an attractive product for conscious consumers.

Effect of Cold Smoking and Natural Antioxidants on Quality Traits, Safety and Shelf Life of Farmed Meagre (Argyrosomus regius) Fillets, as a Strategy to Diversify Aquaculture Products

Aquaculture has been playing a leading role over the years to satisfy the global growing demand for seafood. Moreover, innovative techniques are necessary to increase the competitiveness, sustainability and profitability of the seafood production chain, exploiting new species from the aquaculture, such as meagre (Argyrosomus regius), to develop value-added products and diversify their production. In the present work, the effectiveness of cold smoking combined with antioxidants (SA) compared to cold smoking alone (S) on meagre fillets, the quality and shelf life were investigated. Sensory, biochemical, physical–chemical and microbiological analyses were performed on the smoked fillets during vacuum-packaged storage for 35 days at 4 ± 0.5 °C. The results showed positive effects of the SA treatment on the biochemical parameters of meagre fillets. The total volatile basic nitrogen (TVB-N) in smoked meagre fillets was significantly lower in the SA treatment at the end of storage compared to the S treatment. Moreover, SA had a positive effect on lipid peroxidation. Lower values of malondialdehyde (mg MDA/kg) were observed in the SA treatment during preservation compared to the S treatment. This work will contribute to the growth of the fish production chain, producing a value-added fish product by exploiting meagre, whose production has been increasing over decades.

Effect of salting procedures on quality of hake (Merluccius hubbsi) fillets

The influence of salting procedures on the proximate analysis, mechanical parameters, and color of hake (Merluccius hubbsi) was investigated. Three procedures were comparatively evaluated: dry salting (DS), mixed salting (MS) and brining (BS). MS samples had the highest fat content, a considerable protein content and an equilibrium salt content similar to BS. MS samples had a great water loss, as DS method, but hardness and other mechanical parameters were similar to that obtained with BS, i.e. significantly lower than DS. All samples showed color parameters significantly different as compared to fresh hake, turning more red-orange as the salting time increased. Lightness diminished, a∗ values increased and b∗ values did not show a clear trend throughout the salting time. Principal component analysis (PCA) described the relationship between some variables (z_NaCl, color, and mechanical parameters) with salting time. High Pearson's correlation coefficients were found between z_NaCl and hardness, springiness, cohesiveness and a∗ parameter (r = 0.76, p < 0.001; r = 0.93, p < 0.0001; r = 0.95, p < 0.001 and r = 0.93, p < 0.0001, respectively). Luminosity was negatively correlated with z_NaCl (r = -0.87, p = 0.0001). The correlation curves showed nonlinear relationships (R²_adj between 83.7 % and 97.4 %), which could be used to predict quality attributes of hake fillets as a function of salting time. This work contributed to know the effect of different salting procedures on the quality attributes of a species widely available in the Southwest Atlantic Ocean.

Strategies to reduce sodium levels in European seabass sausages

Considering the increasing demand towards "ready-to-cook" processed seafood products, recognised as being potential contributors to high sodium (Na) intake by consumers, this study aimed to assess the effect of sodium chloride (NaCl) reduction on physicochemical, microbiological and sensory properties of European seabass (Dicentrarchus labrax) sausages stored in chilling conditions during 5 weeks. Three formulations were tested in comparison with a control (100% NaCl, CTR): (i) 50% NaCl+50% ME (oleoresins microcapsules) (F1); (ii) 50% NaCl+50% KCl (F2); and (iii) only 50% NaCl (F3). The NaCl reduction mainly affected the texture and the salty taste, resulting in softer and perceived as less salty sausages after processing. However, hardness differences disappeared after 5 weeks. It seems that an antioxidant protection was obtained in sausages formulated with oleoresins microcapsules. No or low growth of psychrotrophic and mesophilic bacteria was observed (≤2.40 log CFU/g). Decreasing NaCl content and/or partially replacing it (50%) by KCl or oleoresins microcapsules seem to be suitable solutions to reduce Na (30.9-36.3%) levels, while maintaining the chilled sausages quality for 5 weeks. The partial replacement of NaCl by KCl also allows obtaining a product richer in K (997.2 mg/100 g), which ingestion may contribute for a cardiovascular protective effect.

Plant-Based Seafood Analogs

There is a growing global need to shift from animal- towards plant-based diets. The main motivations are environmental/sustainability-, human health- and animal welfare concerns. The aim is to replace traditional animal-based food with various alternatives, predominantly plant-based analogs. The elevated consumption of fish and seafood, leads to negative impacts on the ecosystem, due to dwindling biodiversity, environmental damage and fish diseases related to large-scale marine farming, and increased intake of toxic substances, particularly heavy metals, which accumulate in fish due to water pollution. While these facts lead to increased awareness and rising dietary shifts towards vegetarian and vegan lifestyles, still the majority of seafood consumers seek traditional products. This encourages the development of plant-based analogs for fish and seafood, mimicking the texture and sensorial properties of fish-meat, seafood, or processed fish products. Mimicking the internal structure and texture of fish or seafood requires simulating their nanometric fibrous-gel structure. Common techniques of structuring plant-based proteins into such textures include hydrospinning, electrospinning, extrusion, and 3D printing. The conditions required in each technique, the physicochemical and functional properties of the proteins, along with the use of other non-protein functional ingredients are reviewed. Trends and possible future developments are discussed.

Combination of Freezing, Low Sodium Brine, and Cold Smoking on the Quality and Shelf-Life of Sea Bass (Dicentrarchus labrax L.) Fillets as a Strategy to Innovate the Market of Aquaculture Products

Simple Summary

The growing fish consumption driven by the increased production, the concomitant reduction in wastage, and the huge amount of fish food traded globally, makes it important to address the sustainability, profitability, security, and safety issues related to the seafood production sector. Toward this direction, innovative methods extending shelf-life, maintaining seafood quality, safety and nutritional characteristics and that open new market opportunities, satisfy consumer preferences, and improve product traceability are required. Answering this call, this study aimed to develop a new value added product exploiting a species largely cultured in Italy (i.e., European sea bass). In particular, sea bass fillets were cold smoked using both fresh and frozen fillets to understand the effectiveness of this kind of processing on developing a new fish product and whether the quality of the raw material that could be affected by freezing and thawing could change the quality of the final product. It was seen that the quality of the raw material was affected by the time of frozen storage and that these starting conditions consequently impaired the quality of the smoked fillets. However, cold smoking was proven to be an effective process to develop a valuable product contributing to the growth of the aquaculture sector.

Abstract

Aquaculture is playing a leading role in both meeting the growing demand for seafood and increasing the sustainability of the fish production sector. Thus, innovative technologies that improve its sustainability, competitiveness, and safety are necessary for growth in the sector. This study aimed to develop cold smoked sea bass fillets from aquaculture. The aptitude of frozen and fresh fillets for cold smoking was investigated by processing both fresh and thawed fillets kept previously at −20 °C for 15, 30, 60, and 90 days. Moreover, to develop a low-salt product, fillets were immersed in low-sodium or standard brine. Sensory, biochemical, and physical-chemical analyses were performed on both the raw fillets and the smoked fillets during vacuum packaged storage for 35 days at 1 ± 0.5 °C. Young modulus values, representative of texture and sensory evaluation, showed that the quality of fresh fillets was better compared to the thawed ones, thus affecting the quality of the final product as the correlation between parameters showed (principal component analysis). Cold smoking was effective in both maintaining the total volatile basic nitrogen (TVB-N) below the threshold for spoilage and preventing lipid peroxidation. Moreover, partial sodium replacement by potassium did not alter the sensory attributes of smoked fillets, which maintained high scores up to 21 days.

New formulation for producing salmon pâté with reduced sodium content

Reducing consumption of salt, specifically sodium, is one of the most effective ways to improve public health. A novel formulation for producing salmon pâté with reduced sodium content was investigated. Salmon pâtés with three different sodium concentrations were evaluated using microbiological, sensory and chemical analyses. Saltwell®, a natural salt containing a mixture of sodium chloride and potassium chloride, was used for partial substitution of sodium chloride (table salt) alone in the formulation. Replacing 80% of the sodium chloride with Saltwell®, resulted in a 22% reduction in sodium, without affecting microbial activity. A trained sensory panel observed minor differences in three of the twelve sensory attributes that were evaluated (coherent texture, saltiness, canned fish flavor). However, these differences were only weakly significant. Saltwell is a viable alternative to sodium chloride to produce seafood products with reduced sodium content without compromising quality and safety.

The combined impact of cold smoking and natural antioxidants on quality and shelf life of dolphinfish (Coryphaena hippurus) fillets

This study aimed to produce new value-added products from dolphinfish (Coryphaena hippurus) as fillets when using cold smoking combined with natural antioxidants, obtained from Halocnemum strobilaceum a plant belonging to halophytes. The fillet treatments were controlled (untreated), immersed in standard brine (STD), treated with NaCI and antioxidant before freezing (Aox-pre) and treated with NaCl and antioxidant after thawing (Aox-post). The quality of dolphinfish fillets was assessed using sensory, biochemical, microbiological, and technological parameters. Treating fillets with antioxidants before freezing and cold smoking (Aox-pre) enhanced significantly the shelf life, as well as improved the biochemical, microbiological, and sensory aspects of the product. Aox-pre fillets had the lowest peroxide values (PV) and malondialdehyde (MDA) content, demonstrating that the immediate treatment of fillets with the polyphenols protected lipids from peroxidation. The smoking process, together with antioxidant treatment, significantly reduced microbial counts after 15 days of storage, compared to the control. Overall, combining antioxidant treatments with cold smoking has a positive effect on the quality of Aox-pre fillets with respect to both sensory components and biochemical parameters associated with shelf life. Consequently, Aox-pre treatment enhances the marketability of this species, promoting local and seasonal products, contributing to costal fisheries sustainability.

Diet Affects Muscle Quality and Growth Traits of Grass Carp (Ctenopharyngodon idellus): A Comparison Between Grass and Artificial Feed

Fish muscle, the main edible parts with high protein level and low fat level, is consumed worldwide. Diet contributes greatly to fish growth performance and muscle quality. In order to elucidate the correlation between diet and muscle quality, the same batch of juvenile grass carp (Ctenopharyngodon idellus) were divided into two groups and fed with either grass (Lolium perenne, Euphrasia pectinata and Sorghum sudanense) or artificial feed, respectively. However, the different two diets didn't result in significant differences in all the detected water quality parameters (e.g., Tm, pH, DO, NH3/[Formula: see text]-N, [Formula: see text]-N, [Formula: see text], TN, TP, and TOC) between the two experimental groups. After a 4-month culture period, various indexes and expression of myogenic regulatory factor (MRFs) and their related genes were tested. The weight gain of the fish fed with artificial feed (AFG) was nearly 40% higher than the fish fed with grass (GFG). Significantly higher alkaline phosphatase, total cholestrol, high density cholestrol and total protein were detected in GFG as compared to AFG. GFG also showed increased hardness, resilience and shear force in texture profile analysis, with significantly bigger and compact muscle fibers in histologic slices. The fat accumulation was most serious in the abdomen muscle of AFG. Additionally, the expression levels of MyoG, MyoD, IGF-1, and MSTNs were higher, whereas Myf-5, MRF4, and IGF-2 were lower in most positional muscles of GFG as compared to AFG. Overall, these results suggested that feeding grass could promote muscle growth and development by stimulating muscle fiber hypertrophy, as well as significantly enhance the expression of CoL1As. Feeding C. idellus with grass could also improve flesh quality by improving muscle characteristics, enhancing the production of collagen, meanthile, reducing fat accumulation and moisture in muscle, but at the cost of a slower growth.

Effect of curry leaf and clove bud essential oils on textural and oxidative stability of chill stored sutchi catfish fillets

Effect of coating with curry leaf and clove essential oils (EO) on oxidative and textural stability of sutchi catfish fillets were evaluated during chilled storage. The changes in parameters associated with textural and lipid degradation was also evaluated to ascertain the interactive effect of polyphenols with muscle proteins. Further, the results were compared against vacuum and conventional polyethylene packaging practices. Prior to coating, the properties of antioxidants were evaluated in vitro based on total phenolic and flavonoid contents, 2, 2-diphenyl-1- picrylhydrazyl radical scavenging activity, inhibition of linoleic acid peroxidation, iron reducing power, and metal chelating ability. Coating with clove bud EO was found to be more effective in protecting the textural quality and retarding lipid oxidation of the fillets during chilled storage. Curry leaf EO was found to have only moderate effect.

PRACTICAL APPLICATIONS

In addition to the well-studied antibacterial and antioxidant properties, plant polyphenols have become an intense focus of research for their ability to cross-link proteins that widens their applications for textural and functional modification of food and beverages. Currently, a number of carcinogenic chemicals such as ammonia and formalin are hazardously used to prevent texture deterioration in chilled fish associated with post-rigor changes and microbial reactions. This study evaluates the efficacy of polyphenols present in culinary herbs such as clove bud and curry leaf EO, in stabilising the texture of fish meat during chilled storage. From the results, it could be inferred that both the EO at 0.25% level mediated protein cross-linking/complexation and maintained textural integrity during chilled storage apart from exhibiting antioxidant activities.

Partial sodium replacement in tilapia steak without loss of acceptability

The aim of this study was to evaluate physical and sensory characteristics of low-sodium tilapia steaks restructured with microbial transglutaminase. Polyphosphate (0.4%), condiment mixes-onion powder and garlic powder (2.5%), water (10.0%), transglutaminase (1.0%), and different types of salts (1.5%) were mixed with non-commercial sized fillets. Substitution of NaCl by KCl or MgCl2 (at 50% each) affected quality attributes and decreased (P < 0.05) consumer acceptability. The tri-salt steaks (KCl, MgCl2, and NaCl at 1:1:2 ratio) improved some attributes and increased (P < 0.05) acceptability and purchase intention. We conclude that potassium and magnesium chlorides are possible replacers of salt (NaCl) in restructured tilapia steaks and potentially decrease the risk factor for heart failure associated with high sodium consumption.

Innovative nondestructive measurements of water activity and the content of salts in low-salt hake minces

Impedance spectroscopy (IS), low-field proton nuclear magnetic resonance (LF (1)H NMR), chloride titration, ion chromatography, and an ion selective electrode were used to investigate the physicochemical parameters and measure sodium and potassium contents in low-salt brines and fish. Salt solutions (0-3 w/w, %) and model products of minced hake with added NaCl (0.5-3.0 w/w, %), or a mixture of NaCl and KCl (50/50 w/w, %), were analyzed. Good correlation was observed between the sodium content determined by using the ion selective electrode method and ion chromatography (R(2) = 0.97). In both salt solutions and fish minces, the impedance spectroscopy measurements could detect the difference in salt contents in mince with salt contents down to 0.5%. The NMR transversal relaxation time T2 measurements clearly distinguished samples with 0, 0.5, and 1.0-3.0% salt, based on principal component analysis (PCA). Therefore, LF (1)H NMR seems to be a suitable technique for studies of low-salt products.