Fatty acid composition of three freshwater fishes under different storage and cooking processes

Microbiota diversity of three Brazilian native fishes during ice and frozen storage

This study aimed to assess the bacterial microbiota involved in the spoilage of pacu (Piaractus mesopotamics), patinga (female Piaractus mesopotamics x male Piaractus brachypomus), and tambacu (female Colossoma macropomum × male Piaractus mesopotamics) during ice and frozen storage. Changes in the microbiota of three fish species (N = 22) during storage were studied through 16S rRNA amplicon-based sequencing and correlated with volatile organic compounds (VOCs) and metabolites assessed by nuclear magnetic resonance (NMR). Storage conditions (time and temperature) affected the microbiota diversity in all fish samples. Fish microbiota comprised mainly of Pseudomonas sp., Brochothrix sp., Acinetobacter sp., Bacillus sp., Lactiplantibacillus sp., Kocuria sp., and Enterococcus sp. The relative abundance of Kocuria, P. fragi, L. plantarum, Enterococcus, and Acinetobacter was positively correlated with the metabolic pathways of ether lipid metabolism while B. thermosphacta and P. fragi were correlated with metabolic pathways involved in amino acid metabolism. P. fragi was the most prevalent spoilage bacteria in both storage conditions (ice and frozen), followed by B. thermosphacta. Moreover, the relative abundance of identified Bacillus strains in fish samples stored in ice was positively correlated with the production of VOCs (1-hexanol, nonanal, octenol, and 2-ethyl-1-hexanol) associated with off-flavors. 1H NMR analysis confirmed that amino acids, acetic acid, and ATP degradation products increase over (ice) storage, and therefore considered chemical spoilage index of fish fillets.

Effects of food processing on the lipid nutritional quality of commercially important fish and shellfish

Fish and shellfish are important sources of high quality lipids, especially omega-3 long-chain polyunsaturated fatty acids. In most countries, seafood is eaten cooked to eliminate any potential parasites and pathogens. In addition, cold storage plays an important role in extending the shelf life of seafood. However, both cooking and storage processes can cause alterations in the lipid content and fatty acid profile of fish and shellfish. Although the lipid nutritional quality of fish and shellfish have recently been reviewed, these reviews mainly focus on raw seafood, and information on the impact of food processing on the lipid nutritional quality of fish and shellfish still lacks coherence. Therefore, this study was carried out to provides a critical reviews on the effects of food processing, especially cooking and cold storge, on the lipid nutritional quality of fish and shellfish. Overall, from the perspective of lipid nutritional quality, baking and steaming are the most recommended cooking methods for fish and shellfish, respectively, while it is strongly not recommended to fry seafood with margarine. For cold storage, 3 days and 2 weeks are the most recommended storage periods for refrigeration and frozen storage, respectively. This article can provides consumers with useful information to choose food preparation and storage methods based on their personal interest in specific lipid nutritional quality indicators.

Effects of culinary treatments on the lipid nutritional quality of fish and shellfish

Coronary heart disease (CHD) is one of the leading causes of death worldwide. Seafood, especially fish and shellfish, is a healthy food that reduces the risk of CHD. In many regions, seafood is consumed cooked to eliminate potentially pathogenic microorganisms. Although there have been many reports of culinary preparations causing changes in the fatty acid profile of fish and shellfish, this information has not been well organized, and most of it is not associated to CHD. Therefore, this study was conducted to study the effect of culinary treatments of seafood on lipid nutritional quality in relation to promotion/prevention of CHD. In this study, fatty acid profiles of fish and shellfish prepared with different culinary preparations were obtained from published literature. Lipid nutritional quality indices related to promoting/preventing CHD were calculated and analyzed to reveal the effects of culinary treatment on the lipid nutritional quality of fish and shellfish in promoting/preventing of CHD. The information in this article is very useful and can fill the knowledge gap of the effects of culinary preparation on the lipid nutritional quality of fish and shellfish. Such information is very useful for guiding consumers to choose better ways to cook fish and shellfish to reduce the risk of CHD.

Quantitative risk-benefit assessment of Portuguese fish and other seafood species consumption scenarios

Portugal has high fish/seafood consumption, which may have both risks and benefits. This study aims to quantify the net health impact of hypothetical scenarios of fish/seafood consumption in the Portuguese population using a risk-benefit assessment methodology. Consumption data from the National Food, Nutrition and Physical Activity Survey 2015-2016 (n 5811) were used to estimate the mean exposure to methylmercury and EPA + DHA in the current and the alternative scenarios considered. Alternative scenarios (alt) were modelled using probabilistic approaches to reflect substitutions from the current consumption in the type of fish/seafood (alt1: excluding predatory fishes; alt2: including only methylmercury low-level fishes) or in the frequency of weekly fish/seafood consumption (alt3 to alt6: 1, 3, 5 or 7 times a week, replacing fish/seafood meals with meat or others). The overall health impact of these scenarios was quantified using disability-adjusted life years (DALY). In the Portuguese population, about 11 450 DALY could be prevented each year if the fish/seafood consumption increased to a daily basis. However, such a scenario would result in 1398 extra DALY considering the consumption by pregnant women and the respective risk on fetal neurodevelopment. Our findings support a recommendation to increase fish/seafood consumption up to 7 times/week. However, for pregnant women and children, special considerations must be proposed to avoid potential risks on fetal neurodevelopment due to methylmercury exposure.

Development, characterization and stability of a white cachama pâté-type product (Piaractus brachypomus)

The objective of the work was to formulate, characterize and evaluate the stability of a product based on white cachama (Piaractus brachypomus). From four lipid sources (pork back fat, canola oil, olive oil or sacha inchi oil), the one with the highest acceptance rate was selected based on the acceptance index and sensory characteristics. The formulation was optimized using the response surface method; 15 formulations were used in triplicate, evaluating the pH, moisture, colour and sensory acceptance values. The macronutrient composition and lipid profile of the optimal formulation was determined; its stability was evaluated under refrigeration conditions by measuring lipid and protein degradation, changes in colour, texture, changes at the microbiological and sensory levels. It was found an optimal proportion of inclusion of 50% white cachama pasta, 21% canola oil and 23% water. The stability of the final product obtained was 42 days, with 82% of acceptability index. This product could be an alternative to other pâté-type products from other species.

Effect of Different Cooking Methods on Lipid Content and Fatty Acid Profiles of Mytilus galloprovincialis

The effect of cooking (barbecue-grilling, boiling, microwaving, oven cooking and frying) on lipids, fatty acids (FAs) and lipid quality indices of the mussel Mytilus galloprovincialis was investigated. In general, all processing methods significantly (p < 0.05) modified the fatty acid profiles of mussels, although with major changes in fried samples, which exhibited the lowest saturated fatty acids and n-3 and highest polyunsaturated (PUFA) and n-6 FAs content. A significant decrease in the n-3 PUFA from the raw sample to five cooking methods was observed. The n-3/n-6 ratio decreased from raw (6.01) to cooked mussels, exhibiting the lowest value in fried ones (0.15). C20:5 n-3 and C22:6 n-3 significantly decreased during all cooking processes, and overall in fried mussels. It can be concluded that cooking does not compromise the nutritional quality of mussels except with frying, although it resulted in a decrease of the atherogenic and thrombogenic indices.

The Effect of Different Cooking Methods on The Nutritional Composition f Tilapia (Oreochromis Sp.)

Tilapia (Oreochromis sp.) is a fish that is gaining ground in cultivation and sales because of its nutritional properties: high protein content, vitamins, and minerals with few unhealthy saturated fats as in red meats. This work aimed to evaluate the effect of cooking on the chemical composition, Aw, and pH, in addition to the electrophoretic, and fatty acid profile of the Tilapia using an electric oven, microwave and steaming as cooking methods. The results showed that the nutritional components of Tilapia changed significantly (p<0.05) at two temperatures and at two potencies used. Microwave and steaming preserved better the proteins in the Tilapia after its cooking. Electrophoresis results showed a decrease in intensity and number of bands depending on the type of treatment to which the meat was subjected. On the other hand, the electric oven method at 2 temperatures resulted with the highest increase in essential fatty acids (45% and 36%), with a slight decrease in the ω-6 family, because of a probable hydrolysis or oxidation of the same. The steam cooking showed a slight increase in essential fatty acids, but microwave oven preserved better the proteins, indicating that this could be a good method for cooking Tilapia.

Long-chain Omega-3 Polyunsaturated Fatty Acids in Natural Ecosystems and the Human Diet: Assumptions and Challenges

Over the past three decades, studies of essential biomolecules, long-chain polyunsaturated fatty acids of the omega-3 family (LC-PUFAs), namely eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA), have made considerable progress, resulting in several important assumptions. However, new data, which continue to appear, challenge these assumptions. Based on the current literature, an attempt is made to reconsider the following assumptions: 1. There are algal classes of high and low nutritive quality. 2. EPA and DHA decrease with increasing eutrophication in aquatic ecosystems. 3. Animals need EPA and DHA. 4. Fish are the main food source of EPA and DHA for humans. 5. Culinary treatment decreases EPA and DHA in products. As demonstrated, some of the above assumptions need to be substantially specified and changed.

Effects of preparation on nutrient and environmental contaminant levels in Arctic beluga whale (Delphinapterus leucas) traditional foods

For Canadian Arctic indigenous populations, marine mammal (MM) traditional foods (TFs) represent sources of both important nutrients and hazardous environmental contaminants. Food preparation is known to impact the nutrient and environmental contaminant content of processed items, yet the impacts of preparation on indigenous Arctic MM TFs remain poorly characterized. In order to determine how the various processes involved in preparing beluga blubber TFs affect their levels of nutrients and environmental contaminants, we collected blubber samples from 2 male beluga whales, aged 24 and 37 years, captured during the 2014 summer hunting season in Tuktoyaktuk, Northwest Territories, and processed them according to local TF preparation methods. We measured the levels of select nutrients [selenium (Se), polyunsaturated fatty acids (PUFAs)] and contaminants [organochlorine pesticides, perfluoroalkyl and polyfluoroalkyl substances (PFASs), polybrominated diphenyl ethers, polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs), mercury (Hg)] in raw and prepared (boiled, roasted, aged) beluga blubber TFs. The impacts of beluga blubber TF preparation methods on nutrient and environmental contaminant levels were inconsistent, as the majority of processes either did not appear to influence concentrations or affected the two belugas differently. However, roasting and ageing beluga blubber consistently impacted certain compounds: roasting blubber increased concentrations of hydrophilic substances (Se and certain PFASs) through solvent depletion and deposited PAHs from cookfire smoke. The solid-liquid phase separation involved in ageing blubber depleted hydrophilic elements (Se, Hg) and some ionogenic PFASs from the lipid-rich liquid oil phase, while PUFA levels appeared to increase, and hydrophobic persistent organic pollutants were retained. Ageing blubber adjacent to in-use smokehouses also resulted in considerable PAH deposition to processed samples. Our findings demonstrated that contaminant concentration differences were greater between the two sets of whale samples, based on age differences, than they were within each set of whale samples, due to variable preparation methods. When considering means to minimize human contaminant exposure while maximizing nutrient intake, consumption of aged liquid from younger male whales would be preferred, based on possible PUFA enhancement and selective depletion of hydrophilic environmental contaminants in this food item.

Determining the effect of different cooking methods on the nutritional composition of salmon (Salmo salar) and chilean jack mackerel (Trachurus murphyi) fillets

The effect of four cooking methods was evaluated for proximate composition, fatty acid, calcium, iron, and zinc content in salmon and Chilean jack mackerel. The moisture content of steamed salmon decreased (64.94%) compared to the control (68.05%); a significant decrease was observed in Chilean jack mackerel in all the treatments when compared to the control (75.37%). Protein content in both salmon and Chilean jack mackerel significantly increased under the different treatments while the most significant decrease in lipids was found in oven cooking and canning for salmon and microwaving for Chilean jack mackerel. Ash concentration in both salmon and Chilean jack mackerel did not reveal any significant differences. Iron and calcium content only had significant changes in steaming while zinc did not undergo any significant changes in the different treatments. Finally, no drastic changes were observed in the fatty acid profile in both salmon and Chilean jack mackerel.

Storage Stability of Refined Oil From Lake Victoria Nile Perch (Lates Niliticus) Viscera

Nile perch (Lates niloticus) viscera oil was extracted by wet rendering method and refined by neutralization, deodorization and winterization. After winterization, the oil was decanted and separated by filtration into a low melting point fraction (LMPF) and a high melting point fraction (HMPF). The two fractions were used to carry out storage stability study. Each fraction was stored at room temperature (19 – 23oC) for a period of 20 weeks in transparent and amber colored glass containers. The oil fractions were subjected to quality tests to assess their storage stability. The effects of package color and storage duration were assessed by analyzing for the content of free fatty acids (FFA) as oleic acid and the peroxide value (PV) at the beginning of storage and at intervals of two weeks during storage. The resulting data were subjected to statistical analysis (p ≤ 0.05) using GenStat software, 13th edition. There was a general increase in FFA and PV, with significant differences between oil fractions and package color over storage time. For FFA, there was no interaction between the oil fraction and package color while for PV there was significant interaction between the oil fraction and package color. FFA increased from 0.26% to 0.59% for LMPF in clear package, 0.26 – 0.43% for LMPF in red package, 0.22 – 0.85% for HMPF in clear package, and 0.22 – 0.69% for HMPF in red package. PV increased from 0.50 mEq O2/kg oil to 11.65 mEq O2/kg oil for LMPF in clear package, from 0.5058 mEq O2/kg oil to 10.58 mEq O2/kg oil for LMPF in red package, from 1.01 mEq O2/kg oil to 9.94 mEq O2/kg oil for HMPF in clear package, after 20 weeks, and from 1.01 mEq O2/kg oil – 6.86 mEq O2/kg oil for HMPF in red package after 14 weeks. The levels of FFA and PV of LMPF in colored package remained within the CODEX limits of 0.3% and 5 mEq O2/kg oil respectively for refined fish oils up to 18 weeks. The FFA of HMPF surpassed the limit after 6 and 10 weeks for transparent and colored packages respectively. The FFA of LMPF in transparent package surpassed the limit after 8 weeks. Only low melting point oil fraction in transparent pack had PV above limit at 18 weeks. Results showed that colored package is more suitable for both oil fractions studied. In terms of FFA and PV, HMPF and LMPF can retain good quality at ambient temperatures for 10 and 18 weeks respectively.

Differentiation of fresh and frozen-thawed fish samples using Raman spectroscopy coupled with chemometric analysis

The potential of Raman spectroscopy was investigated in terms of its capability to discriminate the species of the fish samples and determine their freshness according to the number of freezing/thawing cycles they exposed. Species discrimination analysis was carried out on sixty-four fish samples from six different species, namely horse mackerel (Trachurus trachurus), European anchovy (Engraulis encrasicolus), red mullet (Mullus surmuletus), Bluefish (Pomatamus saltatrix), Atlantic salmon (Salmo salar) and flying gurnard (Trigla lucerna). Afterwards, fish samples were exposed to different numbers of freezing/thawing cycles and separated into three batches, namely (i) fresh, (ii) once frozen-thawed (OF) and (iii) twice frozen-thawed (TF) samples, in order to perform the freshness analysis. Raman data collected were used as inputs for chemometric analysis, which enabled us to develop two main PCA models to successfully terminate the studies for both species discrimination and freshness determination analysis.

Effect of six different cooking techniques in the nutritional composition of two fish species previously selected as optimal for renal patient's diet

Benefits of fish consumption are widely known, but there is little information about nutrient values of raw and cooked fish. The aim was to study the impact that six cooking techniques have on the nutritional composition of two fish species with low content of adverse nutrients in renal diet. Raw and steamed, foiled with aluminum, foiled with banana leaf, gas oven-baked, microwave oven-coked and fried lightly samples were chemically analyzed to determine their protein, phosphorus and lipid content. Crevalle jack: all methods increased lipid and protein content and fatty acids (FA) varied in all cooking methods. Phosphorus decreased in the steamed and microwave oven-cooked samples. Red drum: foiled and fried lightly increased lipid content compared to the raw sample. FA concentration changed in all cooking methods. Protein increased with every technique and phosphorus decreased in the steamed and gas oven-baked samples. Renal patients should preferably consume crevalle jack steamed or microwave oven-cooked and red drum steamed or gas oven-baked.

Hypovitaminosis D is common among pulmonary tuberculosis patients in Tanzania but is not explained by the acute phase response

Vitamin D is essential to immune function, but little is known about the vitamin D status in equatorial populations. A cross-sectional study was conducted among pulmonary tuberculosis (PTB) patients in Mwanza, Tanzania to identify the predictors of their vitamin D status. Data on sociodemography, season, and intake of food, alcohol, tobacco, and soil were collected, anthropometric measurements taken, and serum alpha(1)-antichymotrypsin (ACT), ferritin and soluble transferrin receptor (sTfR), and serum 25-hydroxy-(ergocalciferol+cholecalciferol) [25(OH)D] determined. Of the 655 patients studied, 79.7% (508/637) were culture-positive (PTB+) and 47.2% HIV infected. Mean serum ACT, an acute phase reactant, was 0.73 +/- 0.25 g/L with 69.2% >0.6 g/L. Mean serum 25(OH)D was 86.6 +/- 32.9 nmol/L, with 41.2% <75 nmol/L. Serum 25(OH)D was highest during the harvest season, May to July, compared with the remaining year. Single subjects had lower [10.4 (95% CI 4.0; 16.9) nmol/L] serum 25(OH)D concentrations than married subjects and PTB+ patients had concentrations lower [8.2 (95% CI 1.5; 14.9) nmol/L] than PTB- patients. Serum 25(OH)D increased with consumption of a large freshwater fish but not of small dried fish or other foods. BMI and serum TfR were positive predictors of serum 25(OH)D, whereas neither elevated serum ACT nor HIV were predictors. In conclusion, serum 25(OH)D is a valid measure of vitamin D status during the acute phase response. The lower concentrations in PTB+ patients may reflect lower sun exposure or increased utilization. The health consequences of hypovitaminosis D in low-income equatorial populations, at risk for both infectious and chronic diseases, should be studied.

Content of essential polyunsaturated fatty acids in three canned fish species

Three canned fish species--Pacific saury (Cololabis saira), Pacific herring (Clupea harengus) and Baltic sprat (Sprattus sprattus)--most common and popular in Russia, were analyzed for fatty acids. Special attention was paid to long-chain essential polyunsaturated fatty acids: eicosapentaenoic acid (20:5omega3) and docosahexaenoic acid (22:6omega3). Sums of eicosapentaenoic acid and docosahexaenoic acid in saury, herring and sprat were, on average, 2.42, 1.80 and 1.43 g/100 g product, respectively. Contents of these essential acids in all the canned fish species were found to be very high compared with many other fish reported in the available literature. All the canned fish appeared to be highly valuable products for human nutrition concerning the content of eicosapentaenoic and docosahexaenoic acids.