Nutritional value of the Tunisian mussel Mytilus galloprovincialis with a special emphasis on lipid quality

Nutritional quality traits of Mediterranean mussels (Mytilus galloprovincialis): A sustainable aquatic food product available on Italian market all year round

In this study, Mediterranean mussels (Mytilus galloprovincialis) coming from Italian production were purchased in the most important Italian wholesale fish market in different seasons. Biometrical parameters and chemical composition were investigated, with a particular focus on lipid quality and fatty acids (FAs) composition. Results showed a valuable nutritional profile independently by the season of production, represented by high protein and low-fat content, with the lipid portion represented by high amounts of beneficial FAs, particularly the long chain of the n-3 series. Some differences (p < 0.05) were found in carbohydrates and fat content of mussels edible tissues and in FAs profile of specimens collected in different seasons. The most favourable composition in terms of lipid quality was found in mussels collected during spring, corresponding to the moment of the year when mussels store energy reserves in the form of carbohydrates and fat (preparing for the spawning events) and when seawater is enriched in phytoplankton. The lipid health indices calculated (n6/n3, AI, TI) showed optimal values independently by the season of production. The outcomes obtained in this study could help supporting the appreciation of Mediterranean mussels as nutritional valuable seafood product, thus helping encouraging their consumption and promoting the appraisal of this farming sector essential for Italian aquaculture and related to low environmental impact.

Effects of superheated steam processing on the physicochemical properties of sea rice bran

Sea rice bran powder is a new type of instant food additive. Currently, its solubility is low, and its flavor is not pleasant. Superheated steam cooking is a promising treatment in cellulose-rich substances, which essentially improves quality. To gain better sea rice bran powder, physicochemical properties of sea rice bran were investigated using 100 °C, 110 °C, 120 °C, and 130 °C superheated steam treatments for 10, 20, 30, and 40 min. After the treatment, these samples were cooled down, dried, and milled to assess sea rice bran powder's product qualities. Profiles of odor, taste, aroma, and aliphatic acids were determined using e-nose, e-tongue, and gas chromatography-mass spectroscopy. Results revealed that superheated steam brought new profiles of odors and tastes for consumers. Superheated steam treatment was found to decrease swelling capacity. Methane (2,2,4,6,6-pentamethyl, heptane) was seen as a significant odor component, whereas umami and bitterness were considered considerable taste components. Superheated steam treatment retained higher content of aliphatic acids: saturated fatty acids 218-204 mg/100 g and unsaturated fatty acids 830-781 mg/100 g. This study discovered that superheated steam is suitable for processing rice bran as food ingredients; 100 °C-120 °C and 10-30 min could be suggested for suitable cooking sea rice bran.

Hot Air Drying of Sipunculus nudus: Effect of Microwave-Assisted Drying on Quality and Aroma

The present study aimed to investigate the effect of different microwave pre-drying times under hot-air-drying processes on the quality properties and sensory evaluation of Sipunculus nudus (S. nudus). The colour, proximate analysis, amino acid content, fat oxidation, and volatile components of dried S. nudus were determined. Microwave pre-drying could significantly (p < 0.05) increase the drying rate and shorten the drying time. The results of colour, proximate analysis, and amino acid content indicated that microwave pre-drying could improve the quality of the product, resulting in dried S. nudus with less of a loss in nutrients. The samples that underwent microwave pre-drying had a high degree of fatty acid oxidation and low monounsaturated fatty acid content, which facilitated the formation of volatile components. Additionally, the MAD-2 and MAD-3 groups had high relative contents of aldehydes and hydrocarbons, and the FD group had the highest relative content of esters found in the samples. The relative content of ketones and alcohols did not differ significantly between the different drying groups. The finding of this study has important potential for enhancing the quality and aroma of dry S. nudus products with microwave pre-drying during the drying process.

Identification and quantification of lipids in wild and farmed Atlantic salmon ( Salmo salar ), and salmon feed by GC‐MS

The fatty acid profiles of wild and farmed Atlantic salmon (Salmo salar) and salmon feed was elucidated and quantitated. Due to the increasing proportion of vegetable oils in salmon feed, it was of interest to evaluate the effects on the farmed salmon fatty acid profile. There was found to be four times more fat in the muscle in farmed compared to wild salmon, 8.97 ± 0.63% and 2.14 ± 0.32%, respectively. The contents of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids were 15.0%, 55.4%, and 29.6%, respectively, in farmed salmon, while 26.3%, 47.4%, and 26.3% in wild salmon. The lipids were also fractioned into neutral lipids, free fatty acids, and polar lipids by solid‐phase extraction. Both wild and farmed salmon contained approximately equal amount of eicosapentaenoic acid and docosahexaenoic acid with 520 and 523 mg/100 g fish muscle, respectively. The salmons of both kinds were evaluated from a health perspective by discussing the contents of n‐3 and n‐6 fatty acids, saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids together with nutritional quality indices. In conjunction with a lower fat intake by consumption, the wild Atlantic salmon displayed the most nutritionally beneficial profile.

Potential for Coastal and Offshore Aquaculture in Portugal: Insights from Physico-Chemical and Oceanographic Conditions

Physico-chemical and biological parameters along the Portuguese coast were analyzed to evaluate the potential to produce aquatic species of economic interest. Water samples were collected in 2018 and 2019 in five different areas of the Portuguese coast. Currents data were collected between 2018 and 2020 and historical waves height data from 1988 to 2019. According to the results, there is a wide variety of species that can be considered for production. The northernmost area presented the lowest temperature, as well as the highest levels of chlorophyll a, and nitrate. Under such conditions, the rearing of salmon Salmo salar, mussel Mytilus edulis, scallop Pecten maximus, macroalgae Porphyra umbilicalis, and Undaria pinnatifida can be considered. Regarding the southernmost area, due to the highest temperature, this area seems appropriate for the production of meager Argyrosomus regius, sea bream Sparus aurata, sea bass Dicentrarchus labrax, and greater amberjack Seriola dumerili. This study highlights the challenges in deploying aquaculture structures on the Atlantic coast due to its oceanographic conditions. Site selection for aquaculture is a complex process and pilot studies are essential to analyze the feasibility of developing offshore aquaculture along the coast of Portugal.

Black Sea Mussels Qualitative and Quantitative Chemical Analysis: Nutritional Benefits and Possible Risks through Consumption

Mussels have a particular nutritional value, representing a highly valued food source and thus sought after worldwide. Their meat is a real culinary delicacy, rich in proteins, lipids, carbohydrates, trace elements, enzymes, and vitamins. The seasonal variation of mussels’ biochemical composition has been studied to determine the best harvesting period to capitalize on various biologically active fractions. In this work biochemical determinations have been performed on fresh flesh samples of Mytilus galloprovincialis specimens from the Black Sea coast to study seasonal variations in mussels’ biochemical compounds. An analysis of significant lipid classes and the fatty acid composition of lipid extracts obtained from mussel flesh has also been performed. Since mussels retain pollutants from the marine environment, in parallel, the concentration of heavy metals in the meat of mussels collected for the analysis of the chemical composition was investigated. The impact and risk of heavy metal poisoning due to food consumption of mussels contaminated due to pollution of the marine harvesting area was evaluated by the bio-concentration factor of metals and estimated daily intakes of heavy metals through mussel consumption.

Free amino acid, 5'-Nucleotide, and lipid distribution in different tissues of blue mussel (Mytilis edulis L.) determined by mass spectrometry based metabolomics

Blue mussel (Mytilus edulis L.) is a popular, nutritional, and tasty mollusk. To better understand the composition of nutrients and improve further processing of the mussels, metabolomic approaches were used to analyze the free amino acids, 5'-nucleotides, and lipid compositions of different tissues. Our results showed that the viscera and gonad were rich in glutamine and glycine. Adenosine 5'-monophosphate, uridine 5'-monophosphate, guanosine 5'-monophosphate, and inosine 5'-monophosphate were abundant in the mantle, foot, and adductor muscle. Three main types of lipids, phospholipids (PLs), glycerides, and fatty acids (FAs), were semi-quantified. PLs were mainly distributed in the gonad of male mussels and viscera, gonad, and mantles of female mussels. FAs were relatively high in the viscera of males and in the gonad and viscera of females. The viscera of females were rich in phosphatidylcholine, such as 16:0/22:6 and 16:0/20:5. Triglycerides were the key lipids for distinguishing different tissues, especially 16:0/18:1/18:3 and 16:0/18:4/20:5.

Effect of physiological conditions and biochemical factors of mussels Mytilus galloprovincialis in radioactivity monitoring programs along the Algerian coast

A study was carried out to determine the activities of radionuclides (¹³⁷Cs, ⁴⁰K, ²²⁶Ra, ²¹⁴Bi, ²¹⁴Pb, and ²¹⁰Pb) and the levels of biochemical components (lipids, carbohydrates, and proteins) in mussels (Mytilus galloprovincialis) along the Algerian coast. The goal was to evaluate the effect of mussels' biological parameters on radionuclide concentrations, through two coastal water biomonitoring programs. The mussels were taken from three study areas on the Algerian coast: Kristel (Oran), Surcouf (Alger), and Collo (Skikda), for the passive biomonitoring program and transplanted from each study area into the control site of Surcouf. Biochemical components were determined by means of UV-visible colorimetric assays, while the activity concentrations of radionuclides were measured by gamma-ray spectrometry. The results showed that carbohydrates were the most abundant biochemical components (40-60%) compared with proteins (20-40%) and lipids (15-20%). ¹³⁷Cs activity concentrations were below the lower limit of detection (LOD) for all samples, while the high activities of ⁴⁰K are the result of its behavior as stabile potassium K which is extensively used in the metabolism of mussels reflects the conditional state of mussels. ²¹⁰Pb concentration reflects the conditional state of mussels (morphometric parameters and proteins content). The mussels' bioaccumulation capacity for radionuclides was found to be dependent on the growing site and the biomonitoring time period.

Comparative evaluation of high-density polyethylene and polystyrene microplastics pollutants: Uptake, elimination and effects in mussel

The high-density polyethylene (HDPE) and the polystyrene (PS), which are typical microplastic contaminants, are frequently detected in the environment and have potential hazard to environmental health. In this study, the accumulation, elimination, tissue distribution and potential effects of the HDPE and the PS in the mussels (Mytilus galloprovincialis) were evaluated. The HDPE and the PS were found in various tissues (digestive gland > gill > gonad ≈ muscle) with no difference in distribution patterns. The accumulation of the HDPE and the PS rapidly increased in the first 48 h exposure, and the accumulation of HDPE was higher than that of PS. After 144 h of elimination, most of the HDPE and the PS were cleared by mussels. In addition, the activities of superoxide dismutase (SOD), catalase (CAT) and the content of oxidized glutathione considerably increased, indicating that the HDPE and the PS induced oxidative stress and prevented oxidative damage in elimination. The metabolomic analysis suggested that exposure to HDPE and PS induced alterations in the metabolic profiles of mussel. Differential metabolites were involved in energy metabolism, lipid metabolism, tricarboxylic acid cycle and neurotoxic response., and Meanwhile, the PS had a lower effect on mussel metabolism during elimination, but the effect of HDPE was increased. Overall, this study elucidated that the HDPE and the PS caused adverse effects on the mussels and provided insights toward understanding the hazard of different microplastics on aquatic organisms.

The influence of glacial melt and retreat on the nutritional condition of the bivalve Nuculana inaequisculpta (Protobranchia: Nuculanidae) in the West Antarctic Peninsula

Due to climate change, numerous ice bodies have been lost in the West Antarctic Peninsula (WAP). As a consequence, deglaciation is expected to impact the marine environment and its biota at physiological and ecosystem levels. Nuculana inaequisculpta is a marine bivalve widely distributed around Antarctica that plays an important role for ecosystem functioning. Considering that N. inaequisculpta inhabits coastal areas under effect of glacial melt and retreat, impacts on its nutritional condition are expected due to alterations on its physiology and food availability. To test this hypothesis, biochemical composition (lipids, proteins, and fatty acids) and energy content were measured in individuals of N. inaequisculpta collected in a fjord at different distances to the retreating glacier in the WAP. Oceanographic parameters of the top and bottom-water layers (temperature, salinity, dissolved oxygen, and chlorophyll-a) were measured to investigate how the environment changes along the fjord. Results showed that surface oceanographic parameters displayed a lower temperature and dissolved oxygen, but a higher salinity and chlorophyll-a content at nearest compared to farthest sites to the glacier. In contrast, a lower temperature and chlorophyll-a, and a higher salinity and dissolved oxygen was measured in the bottom-water layer toward the glacier. N. inaequisculpta had a higher amount of lipids (17.42 ± 3.24 vs. 12.16 ± 3.46%), protein (24.34 ± 6.12 vs. 21.05 ± 2.46%) and energy content (50.57 ± 6.97 J vs. 39.14 ± 5.80 J) in the farthest compared to the nearest site to the glacier. No differences were found in total fatty acids among all sites. It seems likely that lower individual fitness related to proximity to the glacier would not be related to nutritional quality of sediment food, but rather to food quantity.

Assessment of the biochemical and nutritional values of Venerupis decussata from Tunisian lagoons submitted to different anthropogenic ranks

The present study aimed to evaluate the biochemical status of Venerupis decussata collected seasonally from two Tunisian coastline lagoons (Ghar El Melh and Boughrara) submitted to different anthropogenic levels. Trace elements were significantly higher in clams from Boughrara, especially during the warm season. Fatty acids, proximate compositions, and nutritional value of both clam populations were higher, appearing to be the best for human consumption principally during the spring season. The principal component analysis was determined, including phospholipids and reserve lipids, revealing a great variation with the exogenous and endogenous factors. Generally, clams from Boughrara had a significant alteration in biochemical composition principally due to the anthropogenic levels and physicochemical fluctuation of this lagoon. Our results reflected the healthy benefit of clam consumption and the use of energy reserves and essential fatty acids as a great biomarker to assess ecological risk in lagoons and other coastal ecosystems.

A multimetric approach to evaluate offshore mussel aquaculture effects on the taxonomical and functional diversity of macrobenthic communities

A multimetric approach was used to detect structural, compositional, and functional shifts in the underlying macrobenthic communities of an offshore mussel (Mytilus galloprovincialis) farm in a Portuguese Aquaculture Production Area. Sampling stations distributed inside and outside this area were used to evaluate sediment descriptors and macrobenthic samples collected before (April and September 2010) and after (June and September 2014) the initiation of mussel farming. Sediment fine fraction, organic matter content, and trace element concentrations were found to increase with depth, independently from the mussel farm. Moreover, the structure and composition of the macrobenthic communities were likewise structured by depth. Turnover was the dominant temporal and spatial pattern of beta diversity for all communities. Furthermore, the functional diversity of these communities was unaffected by the mussel farm. These results suggested that an offshore profile allowed hydrodynamic conditions to weaken the impact of mussel farming and highlighted the importance of conducting an integrative multimetric analysis when studying aquaculture impacts on benthic communities.

Polyunsaturated fatty acids and nutritional quality of five freshwater fish species cultivated in the western region of Santa Catarina, Brazil

Abstract There is a paucity of information about the chemical composition of commercially important freshwater fish species (Nile tilapia, bighead carp, grass carp, common carp and silver carp) cultivated in the western region of Santa Catarina, Brazil. This study determined the moisture, ash, protein and lipid contents and the fatty acid composition, as well as the nutritional quality of the lipids in fillets of these five freshwater fish species. Moisture was the most prominent fish component (74.7%-81.7%), followed by protein (15.8%-18.8%) and lipids (0.4%-8.2%). Saturated palmitic acid (90-1740 mg/100 g) and monounsaturated oleic acid (70-2260 mg/100 g) were the major fatty acids found in all the fish species. The grass and common carps and Nile tilapia (caged) had high contents of γ-linolenic acid (GLA), with an average of 536 mg/100 g. Bighead carp was the richest source of ω-3 PUFA, mainly eicosapentaenoic (EPA, 400 mg/100 g) and docosahexaenoic (DHA, 620 mg/100 g) acids, and had the highest ω-3/ω-6 ratio of 6.11. The nutritional evaluation of the fatty acid profile indicated that average values were: atherogenicity index (AI) ~0.59, thrombogenicity index (TI) ~0.82, hypocholesterolemic/hypercholesterolemic ratio (H/H ~1.98), polyunsaturated/saturated ratio (P/S) ~0.43 and ω-3/ω-6 ratio ~2.18, values suggesting that the consumption of these freshwater fish species could be of benefit to human health.