Gulls in Porto Coastline as Reservoirs for spp.: Findings from 2008 and 2023.

Gulls act as intermediaries in the exchange of microorganisms between the environment and human settlements, including spp. This study assessed the antimicrobial resistance and molecular profiles of spp. isolates obtained from fecal samples of gulls in the city of Porto, Portugal, in 2008 and 2023 and from water samples in 2023.

An Exploratory Study on Spoilage Bacteria and in Fresh Salmon: Extending Shelf-Life Using Vacuum and Seasonings as Natural Preservatives.

A growing population increases the demand for food, but short shelf-lives and microbial hazards reduce supply and increase food waste. Fresh fish is highly perishable and may be consumed raw, such as salmon in sushi. This work aims to identify strategies to improve the shelf-life and safety of fresh salmon, using available methods (i.

Combined Effects of Temperature and Dietary Lipid Level on Body Composition, Growth, and Freshness Profile in European Seabass, .

A fish trial was carried out to evaluate the combined effects of temperature and dietary lipid level on the body composition, growth performance, and freshness profile of the European seabass (). Fish were kept for 56 days at 20 °C and 24 °C and fed on two diets, with 16% and 20% lipid. At the end of the trial, fish were euthanized at two temperature conditions (0.

Improved approach based on MALDI-TOF MS for establishment of the fish mucus protein pattern for geographic discrimination of Sparus aurata.

Food fraud is still a recurrent practice throughout food supply chains. In the case of seafood, misidentification of species and products repackaging constitute the most common frauds. Therefore, the development of appropriate analytical approaches to be used against food fraud is necessary.

Seasonal Evaluation of Freshness Profile of Commercially Important Fish Species.

Freshness is considered one of the most important parameters to judge the quality of most fish products. In the current study, the seasonality effect on the freshness profile of different economic fish species was evaluated for the first time, using three different approaches (sensory: Quality Index Method (QIM) and European (EC) Scheme; physical: Torrymeter (TRM) values; and microbiological analyses: Total Viable Counts (TVC) and degradative bacteria). Over a year, individuals of farmed fish and , as well as the wild fish , , and , were sampled seasonally for the evaluation of their freshness profile over 10 days on ice.

Multi-elemental composition of white and dark muscles in swordfish.

Concentrations of 16 elements (K, Na, Mg, Ca, Fe, Zn, Hg, Se, As, Cu, Cd, Mn, Ni, Cr, Pb and Co) were determined in dorsal white and dark muscle of Xiphias gladius, sampled at various positions of a single swordfish and at the same position of eight specimens. Hg was quantified by thermal decomposition atomic absorption spectrometry (LECO AMA-254) and the rest of the elements by inductively coupled plasma optical emission spectrometry (ICP OES) or mass spectrometry (ICP MS). Element partitioning differed in dark and white muscle.

A Systematic AQbD Approach for Optimization of the Most Influential Experimental Parameters on Analysis of Fish Spoilage-Related Volatile Amines.

The volatile amines trimethylamine (TMA) and dimethylamine (DMA) could be used as important spoilage indices for seafood products, assisting in the determination of the rejection period. In the present study, a systematic analytical duality-by-design (AQbD) approach was used as a powerful strategy to optimize the most important experimental parameters of headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) conditions for the quantification of TMA and DMA in . This optimization enabled the selection of the best points in the method operable design region for HS-SPME extraction (30 min; 35 °C; NaOH 15 M and NaCl 35%, ) and GC-MS analysis (80 °C; gradient 50 °C/min; flow rate 1 mL/min and splitless mode).

Freshness Assessment and Shelf-Life Prediction for from Aquaculture Based on the Quality Index Method.

Fish and fish-based products are easily perishable foods due to different factors, including fragile organization, abundant endo-enzymes, psychrophilic bacteria, and impact of pre-harvest operations, that contribute to reducing its value. Therefore, a timely effective method for fish freshness and shelf-life evaluation is important. In this context, this study aimed to develop a sensory scheme based on the Quality Index Method (QIM) (sensory table and point system) for freshness monitorization and shelf-life prediction for from aquaculture in Madeira Island.

Elemental composition and bioaccessibility of farmed oysters () fed different ratios of dietary seaweed and microalgae during broodstock conditioning.

The Pacific oyster () culture has been expanding, thereby leading to a greater importance of hatcheries. Broodstock conditioning is very important in the hatchery process, in which diet composition may have a strong influence on the offspring production and quality. Therefore, the current study evaluated elemental composition and bioaccessibility of oysters fed different ratios of dietary seaweed (SW) and microalgae.

Fatty Acid Profile of Pacific Oyster, Crassostrea gigas, Fed Different Ratios of Dietary Seaweed and Microalgae during Broodstock Conditioning.

The fatty acid (FA) profile of oysters generally reflects the dietary FA composition. Moreover, incorporation of FA into tissues is modulated by various metabolic factors, and final composition will depend upon the dietary sources, cumulative intake, and oysters' development stage. Thus, the aim of this study was to assess the impact of dietary incorporation of seaweed (SW) Ulva rigida, in replacement of traditional microalgae diet, on the FA composition of Pacific oysters Crassostrea gigas, during broodstock conditioning.

Genetic diversity and population structure of the blue jack mackerel Trachurus picturatus across its western distribution.

Blue jack mackerel Trachurus picturatus collected at six sampling locations of the north-east Atlantic Ocean (Azores, Madeira, Canaries, and Matosinhos, Peniche and Portimão, mainland Portugal) and one location in the Mediterranean (Sicily), were used to examine the genetic structure of this species. Three mitochondrial gene regions (cytochrome c oxidase subunit I, cytochrome b and control region) were used to study the genetic structure of the species in Macaronesia, as well as to compare the genetic diversity of this region with published results from its eastern distribution. All markers indicated the absence of genetic structure among populations, with high indices of genetic diversity.

River water analysis using a multiparametric approach: Portuguese river as a case study.

The Ave River in northern Portugal has a history of riverbanks and water quality degradation. The river water quality was assessed by physicochemical, biological (macroinvertebrates) and microbiological (Enterococcus spp. and Escherichia coli) parameters in six locations (A-F, point A being the nearest to the source) throughout its course during a year.

Viability of dietary substitution of live microalgae with dry in broodstock conditioning of the Pacific oyster ().

The current study evaluated the microalgae replacement by dry macroalgae () in the reproductive success and biochemical composition of the Pacific oyster () during broodstock conditioning. Five nutritional regimes were tested: 100% macroalgae (diet 1), 50% macroalgae+50% microalgae (diet 2), 25% macroalgae+75% microalgae (diet 3) and 100% microalgae (diet 4). An unfed group was used as a negative control.

Influence of temperature and fish thickness on the mass transfer kinetics during the cod (Gadus morhua) desalting process.

Background: The aim of this study was to analyse the influence of desalting temperature, fish thickness and desalting time on the mass transfer kinetics during the cod desalting process by physico-chemical analyses.

Results: Both water uptake and salt loss increased with increasing temperature (15 °C > 10 °C > 5 °C) up to 24 h in 'thicker' pieces. The equilibrium achievement was faster in 'thinner' pieces and also with increasing temperature.

MULTIDRUG RESISTANCE IN WILD BIRD POPULATIONS: IMPORTANCE OF THE FOOD CHAIN.

The presence of multidrug-resistant (MDR) Escherichia coli has recently been reported in wild birds (gulls and birds of prey) that had no apparent exposure to antimicrobials. Little work has been done to assess the role of the food chain in the emergence and spread of MDR E. coli .

Quality changes during cod (Gadus morhua) desalting at different temperatures.

Background: To advise consumers and manufacturers regarding decreasing the time needed to desalt salted cod (a time-consuming process), there is a need to develop knowledge about quality changes at different desalting temperatures. The objective of this work was to evaluate the physico-chemical, microbiological and sensory quality changes and their causes during cod desalting at 5, 10 and 15 °C, using a cod/water ratio of 1:9 without water changes. The influence of slices with different thickness and different desalting times was also evaluated.

High prevalence of multidrug-resistant Escherichia coli and Enterococcus spp. in river water, upstream and downstream of a wastewater treatment plant.

In this study, microbial quality and antimicrobial resistance of faecal bacteria from a Portuguese river were assessed. River water samples collected upstream and downstream of a wastewater treatment plant, throughout a 3-month period, were used for the enumeration of Escherichia coli and Enterococcus spp. The highest numbers found for E.

Effect of seasonal changes on the gelling properties of farmed sea bass (Dicentrarchus labrax).

The effect of seasonal changes (summer versus winter) upon the quality of heat-induced gel products from farmed sea bass (Dicentrarchus labrax) was studied. Moreover, the effect of microbial transglutaminase addition (0.5%, w/w) on the quality was assessed.

Effect of season on the chemical composition and nutritional quality of the edible crab Cancer pagurus.

Cancer pagurus is most appreciated in southern Europe for its muscle and brown meat content. In Portugal, consumption occurs mostly in summer and at Christmas. In this study the seasonal nutritional quality of edible tissues of female and male C.

Changes in antimicrobial resistance among faecal enterococci isolated from growing broilers prophylactically medicated with three commercial antimicrobials.

A controlled environment poultry house (1600m(2)) was divided into two separated compartments. Three hundred twenty chick containers (each containing 100 chicks) were randomly allocated to each compartment. Antimicrobial products were provided (via drinking water) to one broiler group in three different growth phases for prophylactic purposes: lincomycin associated with spectinomycin from day 1 to day 3, trimethoprim associated with sulfamethoxazole from day 19 to day 21, and tylosin from day 26 to day 28.

Influence of season and sex on the contents of minerals and trace elements in brown crab (Cancer pagurus, Linnaeus, 1758).

Cancer pagurus is much appreciated in Southern Europe, where the muscle, hepatopancreas, and gonads are consumed regularly with peaks in summer and December. The elemental contents of C. pagurus edible tissues were analyzed in this study during the four seasons.

Nutritional quality of the edible tissues of European lobster Homarus gammarus and American lobster Homarus americanus.

The clawed lobsters Homarus gammarus and Homarus americanus are high-priced and appreciated food items in southern Europe. From a nutritional point of view there is still limited information on the chemical composition of edible tissues (muscle, hepatopancreas, and gonads) of both species. Therefore, the aims of the present work were to study the proximate chemical composition, energy, fatty acid and amino acid profiles, and cholesterol content in each edible tissue of both species and to evaluate their nutritional quality.

Effects of antimicrobial treatment on selection of resistant Escherichia coli in broiler fecal flora.

Under field conditions, three commercial antimicrobials were sequentially prescribed to 16,000 broiler chickens during their rearing period, via drinking water using subtherapeutic levels for 3 days. A control group of 16,000 broilers was placed in the same controlled environment poultry house. Feed diet and fecal samples from both groups were collected periodically.

Accumulation of elements (S, As, Br, Sr, Cd, Hg, Pb) in two populations of Cancer pagurus: ecological implications to human consumption.

The brown crab Cancer pagurus is highly appreciated in Southern European countries and edible tissues are consumed separately or as mixtures. This species is mostly harvested along the Scottish Coast and English Channel and has different market prices depending on the catching area and sex. The aim of this study was to quantify and characterize the contents of S, As, Br, Sr, Cd, Hg and Pb in muscle, hepatopancreas, gonads and gills of female and male crabs from both catching areas.

Antimicrobial resistance in Escherichia coli isolated in wastewater and sludge from poultry slaughterhouse wastewater plants.

The authors investigated the antimicrobial resistance of Escherichia coli isolates in 22 samples of crude inflow, treated effluent, and sludge collected at the wastewater treatment plants of eight poultry slaughterhouses in Portugal. A total of 549 E. coli strains were recovered and tested for resistance to 12 antimicrobial agents.