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The aim of this work is the description and characterization of a severe Microsporidia infection in a batch of salted and dried cod. Particularly, the case involves a batch of approximately 800 kg obtained from Gadus macrocephalus (Food and Agriculture Organization Zone 61 - Northwest Pacific Ocean), which, after rehydration and sectioning operations, underwent routine company checks before packaging. On about 20% of the samples, the presence of whitish nodules with a diameter ranging from 1 to 2 mm was observed on the surface of the fillets and in cross-section. The lesions ranged from a few units to 10 per cm2. Some samples were subjected to fresh microscopic observation with the stereomicroscope, confirming the nodular nature of the lesions, which were often confluent, alternating with empty spaces, giving the tissue a honeycombing aspect. The histological examination at low magnification allowed us to observe the heavy vacuolization of nodular lesions irregularly surrounded by a spongy-like wall. The observation at higher magnification of other sections allowed us to identify intra-myofibrillar cists containing presumptive microsporidian elements. The tissue damage derived from the technological processes and gravity of lesions did not allow a morphological characterization of presumptive protozoans. The molecular examination of the nodular lesions and the analysis of the sequence of an 897 bp fragment of the small subunit 16S rRNA revealed 100% identity with Microsporidium theragrae (GenBank Accession number MT928885-89) first isolated from the skeletal muscles of Gadus chalcogrammus specimens from the Sea of Okhotsk. This finding confirms the importance of selecting suppliers and raw materials in the seafood industry, as well as the usefulness of an effective traceability system.

The genus Aeromonas includes well-known pathogenic species for fishes and humans that are widely distributed in the aquatic environment and foods. Nowadays, one of the main issues related to wild Aeromonas isolates is their identification at the species level, which is challenging using classical microbiological and biomolecular methods. This study aims to test MALDI-TOF MS technology in the identification of Aeromonas strains isolated from n. 60 retail sushi and sashimi boxes using an implemented version of the SARAMIS software V4.12. A total of 43 certified Aeromonas strains were used to implement the SARAMIS database by importing the spectra obtained from their identification. The original SARAMIS version (V4.12) failed to recognize 62.79% of the certified strains, while the herein-implemented version (V4.12plus) allowed the identification of all the certified strains at least to the genus level with a match of no less than 85%. Regarding the sushi and sashimi samples, Aeromonas spp. was detected in n. 18 (30%) boxes. A total of 127 colonies were identified at the species level, with A. salmonicida detected as the most prevalent species, followed by A. bestiarum and A. caviae. Based on the results of the present study, we could speculate that MALDI-TOF technology could be a useful tool both for the food industry to monitor product contamination and for clinical purposes to make diagnoses effectively and quickly.

Microplastics (MPs) (0.1 µm–5 mm particles) have been documented in oceans and seas. Bivalve molluscs (BMs) can accumulate MPs and transfer to humans through the food chain. BMs (especially mussels) are used to assess MPs’ contamination, but the genus Donax has not been thoroughly investigated. The aim of this study was to detect and characterize MPs in D. trunculus specimens collected along the Tuscan coast (Italy), and to assess the potential risk for consumers. The samples (~10 g of tissue and intervalval liquid from 35 specimens) were digested using a solution of 10% KOH, subjected to NaCl density separation, and filtered through 5 μm pore-size filters. All items were morphologically classified and measured, and their mean abundance (MA) was calculated. Furthermore, 20% of them were analyzed by Raman spectroscopy and, based on the obtained results, the MA was recalculated (corrected MA) and the annual human exposure was estimated. In the 39 samples analyzed, 85 items fibers (n = 45; 52.94%) and fragments (n = 40; 47.06%) were found. The MA was 0.23 ± 0.17 items/grww. Additionally, 83.33% of the items were confirmed as MPs (polyethylene and polyethylene terephthalate). Based on the correct MA (0.18 MPs/grww), D. trunculus consumers could be exposed to 19.2 MPs/per capita/year. The health risk level of MPs was classified as level III (moderate).

Persistent bacteria are a microbial subpopulation that, exposed to bactericidal treatment, is killed at a slower rate than the rest of the population they are part of. They can be triggered either following stress or stochastically without external signals. The hallmark of persistent bacteria is the biphasic killing curve, a sign that, within a microbial population, two subpopulations are inactivated at a different rate. Furthermore, when plated into a fresh medium and in the absence of stressors, persistent bacteria typically remain in the lag phase longer before resuming active replication. This study aims to evaluate in vitro whether the formation of persistent cells in a strain of Listeria monocytogenes can be triggered by exposure to osmotic stress and if this phenomenon can increase heat resistance in the bacterial population. In a first experiment, the lag time distribution of a L. monocytogenes strain grown in a 6% NaCl broth was evaluated using the software ScanLag. A stationary phase broth culture was inoculated on agar plates placed on an office scanner inside an incubator at 37°C. The plates were scanned every 20’ for 4 days and the acquired images were automatically elaborated with the aid of MatLab software in order to evaluate the appearance times of every single colony. The experiment was also carried out on a control culture obtained by growing the strain in the broth without salt. In a second experiment, the same broth cultures, after proper dilutions to rebalance NaCl concentration, were subjected to a heat treatment at 51°C and the death curves obtained were parameterized using the GinaFit system. Results showed that the lag phase of 31.40% of the salt culture colonies was long enough to suppose the formation of persistent bacteria. Analyses of the thermal survival curves showed that the shoulder and tail model was the one that best represented the inactivation trend of the salt culture, unlike the control culture, whose trend was essentially linear. Results of the present study show how exposure to salt could induce the formation of persistent bacteria in a L. monocytogenes strain. The last raises concerns as persistent cells may not only be undetected with common analytical techniques but they even show a greater heat resistance.

Background and Aim: Balantidiasis, caused by Balantidium coli (syn. Neobalantidium coli or B. coli), represents a neglected parasitic infection of zoonotic significance affecting a variety of hosts, including domestic pigs that are the main reservoir. B. coli has a direct life cycle with a fecal-oral route transmission that occurs mainly by the ingestion of food and water contaminated with cysts. The ingestion of meat contaminated during inappropriate slaughtering processes may represent a new potential route of transmission. Only a few studies have investigated the prevalence of B. coli in domestic pigs in Italy, despite its high prevalence and zoonotic significance. This study aimed to improve the knowledge on B. coli prevalence in domestic swine reared both in intensive and "en plein air" breeding systems in the south of Italy. Materials and Methods: The infection rate of B. coli in pigs bred in 15 different pig farms and regularly slaughtered in South Italy, in the Calabria region, was investigated. From 2017 to 2019, 177 terminal parts of the rectums of pigs, of which 91 commercial hybrids and 86 autochthonous (Nero Calabrese), reared, respectively, in intensive and "en plein air" breeding system, were tested for parasite detection. After the slaughtering, the terminal part of the rectum was sampled and transported to the laboratories and immediately processed. For the detection of trophozoites, fresh smears of feces were examined at light microscopy. Moreover, flotation was performed using a sodium chloride solution, then smears of feces were dispersed on microscope slides and examined at light microscopy. The observed parasites were identified at the species level using morphological characteristics. Results: B. coli was detected in a total of 83 (i.e., 46.89%) pigs, with a significantly higher prevalence (p

In the present study, the chemical composition and the in vitro antimicrobial and antibiofilm activity of an ethanolic extract of propolis (EEP) from Tunisia against different ATCC and wild bacterial strains were evaluated. In situ antimicrobial activity and sensory influence of different EEP concentrations (0.5% and 1%), also in combination with 1% vinegar, were evaluated in chilled vacuum-packed salmon tartare. Furthermore, a challenge test was performed on salmon tartare experimentally contaminated with Listeria monocytogenes and treated with the different EEP formulations. The in vitro antimicrobial and antibiofilm activity was observed only against Gram-positive bacteria, such as L. monocytogenes and S. aureus, both ATCC and wild. Results of the in situ analyses revealed significant antimicrobial activity against aerobic colonies, lactic acid bacteria, Enterobacteriaceae and Pseudomonas spp. only when the EEP was used at 1% and in combination with 1% vinegar. The 1% EEP in combination with 1% vinegar was the most effective treatment also against L. monocytogenes, although 0.5% and 1% EEP used alone also showed antilisterial effects. After 7 days of storage, the sensory influence on odor, taste and color of salmon tartare was negligible for all EEP formulations. In this background, results obtained confirmed the antimicrobial efficacy of propolis which could be proposed as a suitable biopreservative to ensure safety and improve the quality of food.

Background and Aim: Vibrio bacteria are autochthonous inhabitants of aquatic and marine environments. Certain strains are responsible for important seafood-borne outbreaks in developed nations. The aim of this study was to investigate the occurrence of Vibrio spp. along the Algerian Mediterranean coast in several samples of two prominent wild and farmed marine fishes, Sparus aurata and Dicentrarchus labrax. Materials and Methods: A total of 350 S. aurata (n=280 farmed and n=70 wild) and 340 D. labrax (n=250 farmed and n=90 wild) were sampled among three different locations along the Algerian Mediterranean coastal area. The samples were processed for Vibrio research according to the ISO methods. Isolated colonies were identified utilizing biochemical tests and consecutively confirmed with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, combined with polymerase chain reaction (PCR) analysis when appropriate, or confirmed with PCR analysis alone. Results: A total of 42 Vibrio spp. were detected only among the farmed fishes. Taking into account, all 690 fishes sampled, the incidence of Vibrio spp. was 6.08% (with peaks up to 7.92%) among the total number of farmed fishes. Overall, 25 strains were isolated from S. aurata and 17 strains were isolated from D. labrax. The isolated strains belonged to four different species and were represented as follows: Vibrio alginolyticus (n=20), Vibrio cholerae (n=15), Vibrio fluvialis (n=5), and Vibrio hollisae (n=2). The incidence of Vibrio was higher in places characterized by greater levels of anthropogenic contamination of seawater. Conclusion: Considering the growing production and consequent rising consumption of farmed fish in Algeria, the reported incidence of Vibrio and the presence of potentially pathogenic strains of Vibrio such as V. cholerae cause particular concern for food safety matters. Even if innovative and natural techniques are desired in aquaculture, proper hygiene and manufacturing practices are essential for the correct management of Vibrio infection risk in farmed fishes at both industrial and domestic levels.

This study aims to evaluate the behaviour of Listeria monocytogenes under fluctuating temperature comparing the efficacy of deterministic and stochastic methods for its prediction. In the first part of the study, a strain of L. monocytogenes was maintained at two different fluctuating temperature regimes both from 2 to 8 C and regularly sampled for the quantitative determination. The first temperature regime lasted 204 hours with a fluctuation length of 12 hours whereas the second lasted 167 hours with a fluctuation length of 24 hours. A dynamic predictive model was implemented for the reproduction of the observed data. Model resolution has been carried out by using values of the recorded temperature as well as the value of the mean temperature, the kinetic mean temperature, the 75th and 95th percentile of the temperature. A stochastic resolution was also performed considering the mean temperature and Standard Deviation as stochastic variable. In the second part of the study, a temperature mean curve was constructed by monitoring temperature of 8 refrigerated conveyances, 10 display cabinet and 15 domestic refrigerators. This curve was used to obtain predictive scenarios for L. monocytogenes based on the above and also considering temperature regime suggested by the EURL Lm TECHNICAL GUIDANCE DOCUMENT on challenge tests and durability studies for assessing shelf-life of ready-to-eat foods related to Listeria monocytogenes (Version 4 of 1 July 2021). All predicted behaviours were compared to the observed ones through the Root Mean Squared Error. Firstly, dynamic predictive model as well as the stochastic one, provided the best level of reproducibility of the observed data. The kinetic mean temperature reproduced the observed data better than the mean temperature for the 12 hoursregime while for the 24 hours-regime was the opposite. The 75th and 95th percentile overestimated the observed growths. Secondary, predictions obtained with the mean temperature, kinetic temperature and stochastic approach well fitted the observed data. The 75th and 95th percentile of Temperature and the “Eurl LM” temperature regimes overestimated the observed prediction. Dynamic approach as well as the stochastic one allowed to obtain the lowest values of Root Mean Squared Error. The mean temperature and kinetic mean temperature appeared the most representative values in a deterministic “single-point” approach.

Despite its commercial value, the shelflife of the Atlantic mackerel (Scomber scombrus) during refrigerated storage was poorly investigated. In this regard, the Quality Index Method (QIM) was proposed as a suitable scoring system for freshness and quality sensorial estimation of fishery products. This study aims to develop a deterministic mathematical model based on dynamic temperatures conditions and a successive statistical analysis of the results obtained. This model will be exploited to predict the shelf-life of the Atlantic mackerel based on specific storage temperatures. A total of 60 fresh fishes were subdivided into two groups and respectively stored in ice for 12 days at a constant temperature of 1 0.5 C (Group A) and a fluctuating temperature ranging between 1 and 7 C (Group B). Microbiological analysis and sensory evaluation through the QIM were performed on each fish at regular time intervals. A critical value of 6 Log cfu/g of spoilage bacteria (mainly psychotropic) associated with a significant decay of the sensorial characteristics was exceeded after 9 days of storage for Group A and 3 days for Group B. A reliable prediction of fish freshness was obtained by modelling the QIM as a function of the spoilage bacteria behaviour. A coefficient β of correlation was determined to convert the spoilage bacteria load into a Quality Index score. The adoption of mathematical predictive models to assess microbial behaviour under different environmental conditions is an interesting tool for food industries to maximize production and reduce waste.

It is widely accepted that human is exposed to microplastics through food consumption, however data occurrence in foodstuffs are still little and basically limited to seafood. In this study, the presence of microplastics was investigated in icefish (Neosalanx spp.) samples sourced from various mass-market retailers in Italy, supplied as frozen, glazed and vacuum-packed product. Icefish is a small freshwater fish widely imported in Europe from China as surrogate of other fish species subjected to commercial restriction, consumed whole after cooking in several culinary preparation. The samples (~10 g of icefish from each of the 40 packs tested) were digested using a solution of 10% potassium hydroxide and filtered through a 5 μm pore-size filter. Filters of the samples were observed under a stereomicroscope and the chemical composition of the items detected were analysed by FTIR spectroscopy. A total of 163 items were counted in 37 (92.5%) samples with a mean value of 0.42±0.28 items/g w.w. Fibers were the most detected morphotype and several plastic polymers, such as polypropylene, polyethylene, polyethylene terephthalate and polystyrene, were identified by FT-IR analysis. As store-bought samples, the sources of microplastics could be substantially related to contamination during food processing. However, an intravital exposure to microplastics present in the surroundings waters cannot be ruled out. More foodstuffs need to be investigated for microplastic presence. In this study, microplastic occurrence was reported in freshwater biota intended for human consumption sampled directly from supermarket contributing to the risk assessment of human exposure to microplastics via food consumption.

Removal of para-nitrophenol (p-NP) from an aqueous solution was studied under various batch adsorption experiments, using alumina (Al2O3) and its composite hexadecyltrimethylammonium bromide (HDTMA+-Br−) as adsorbents. These were later characterized, before and after adsorption of p-NP, by thermal analysis (DSC-TG), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and UV/Visible spectroscopies. The results show that HDTMA+/Al2O3 adsorbents have a greater affinity toward p-NP than Al2O3 alone. Linear and non-linear forms of kinetics and isotherms were used to analyze the experimental data obtained at different concentrations and temperatures. The results indicate that the pseudo-second order kinetic model provided the best fit to the experimental data for the adsorption of p-NP on both adsorbents, and that the intra-particle diffusion was not only the rate controlling step. Both the Langmuir and Redlich-Peterson (R-P) models were found to fit the sorption isotherm data well, but the Langmuir model was better. Physical adsorption of p-NP onto the adsorbents proved to be an endothermic and spontaneous process at high temperatures, which mainly involves a hydrogen bonding mechanism of interactions between p-NP and functional groups of adsorbents. The antibacterial activity of Al2O3, HDTMA+-Br− and HDTMA+/Al2O3 were evaluated against Listeria monocytogenes and Salmonella spp. strains using both disc diffusion and broth microdilution methods. The HDTMA+-Br− and HDTMA+/Al2O3 displayed a bacteriostatic effect against all tested strains of Listeria monocytogenes and Salmonella spp., while Al2O3 exhibited no bacterial effect against all bacterial strains tested.

Anisakiasis is a fish-borne zoonotic disease caused by the ingestion of raw/undercooked fishes or cephalopods parasitized by members of the genus Anisakis. Freezing ensures the inactivation of viable Anisakis larvae; however, since it affects the organoleptic properties of food, essential oils and their compounds were proposed as an alternative. In this study, fresh anchovy fillets were experimentally parasitized with L3 Anisakis larvae to test the anisakicidal efficacy of R (+) limonene (LMN) in marinated fishery products. The anisakicidal effectiveness and organoleptic influence of several LMN concentrations (0.5%, 1%, and 5%) were tested during the marinating process (MS) and storage in sunflower seed oil (SO) of marinated anchovy fillets. Double treatment (DT) with 1% LMN was also performed both during marination and subsequent storage in oil. MS treatment resulted only in a reduction in larvae viability after 48 h, while a complete inactivation was observed in SO after 8, 10, and 20 days of treatment with 5%, 1%, and 0.5% LMN, respectively. DT was the most effective with complete larval inactivation after 7 days. Only 5% LMN influenced the sensory characteristics of the fillets, resulting, however, in a pleasant lemon-like odor and taste. Considering the results obtained, LMN might be a suitable natural alternative to manage Anisakis risk in the fishery industry.

The aim of this work is to study the effect of temperature fluctuations on spoilage microbial flora behaviour of a semi-preserved seafood product in modified atmosphere packaging (MAP) as well as to find correct interpretation criteria for simulating temperature fluctuations during storage tests. The study concerned 54 packages of “Octopus carpaccio” that were grouped in three batches and stored at 3 different temperature profiles: the first (16 packages - Group 4°C) was stored at 4±0.5°C; the second (16 packages - Group 8°C) was stored at 8±0.5°C; the third (16 packages - Group F) was stored under a fluctuating temperature regime between 2°C and 14°C. Spoilage microflora, pH and AW has been monitored, at regular intervals, along the storage period (44 days). A predictive model was constructed according to the accredited scientific literature and validated against the observed growth curves of the above three groups. Afterwards, the predictive model has been used setting the temperature at the mean value of fluctuations (6.72°C), at the kinetic mean value of fluctuations (7.80°C) and at the 75th percentile value of fluctuations (11.14°C). The best fitting to the observed data was obtained with the kinetic mean temperature value and this result shows that this parameter can be proposed to reproduce the temperature fluctuation along the distribution and the domestic storage when a storage test has to be carried out.

Ice cream is a frozen dairy dessert consumed worldwide. The frozen state may give a positive impression regarding microbiological safety; however, transmission of foodborne pathogens can also occur through ice cream consumption. A total of 200 samples of milk-based industrial ice cream, with and without inclusions, were purchased at different mass-market retailers in Italy and analyzed for the detection and enumeration of the aerobic colonies, Enterobacteriaceae, coagulase-positive staphylococci, Salmonella spp. and Listeria monocytogenes. Results were classified according to different ranges of acceptability, whose limits were set for each microbiological parameter. Unsatisfactory loads were obtained for two and nine samples as regarded the aerobic colonies and Enterobacteriaceae, respectively. L. monocytogenes was detected in 16 samples, and in three of them, the loads exceeded the legal limit of acceptability (≤100 cfu/g) during marketing. No unsatisfactory loads were obtained for coagulase-positive staphylococci and no Salmonella spp. was detected. The results obtained allow speculation that inclusions may be a relevant source of contamination for industrial ice cream. However, inadequate manufacturing and hygiene practices also threaten the safety of the finished product. Ice cream is a complex food matrix, and a comprehensive approach to the whole production system is required to ensure high standards of quality and safety.

Spices and aromatic herbs have always had great historical importance in human nutrition. Their use has been documented for centuries as a rich source of bioactive compounds; they have been used for their health benefits and also for flavoring or coloring food. However, despite the many health properties linked to the use of spices and aromatic herbs, these can represent biological hazards and can contain chemical substances of concern. Certainly, monitoring potential health hazards in spices and aromatic herbs includes microbiological safety and also the content of inorganic substances: both represent a key step. This research aims at monitoring the compliance of various spices and aromatic herbs from a non-European country market (namely: black cumin seeds, Iranian Tokhme Sharbati, clove buds, Shahjeera, Abbaszadeh saffron, organic fenugreek, whole black pepper, cinnamon, Abthul Ahmar (Asario), Ajwan seeds, whole coriander seeds, black sesame seeds, Sabja seeds) with the current European Union (EU) and WHO regulations, when available, regarding mineral and microbiological parameters. In particular, microbiological assays using rapid and conventional methods, and trace mineral determination by inductively coupled plasma mass spectrometry (ICP-MS) were performed. Results show the safety of the tested spices, given that the microbiological parameters were within the legal microbiological criteria set by the European Commission Regulation (EC) No. 2073/2005 and its amendment Regulation (EC) No. 1441/2007. With reference to potentially toxic Cd, Pb, As, Hg, these were within the limits set by the European Commission Regulation (EC) No. 1881/2006 and its amendments, Regulation (EU) No. 1317/2021 and Regulation (EU) No. 1323/2021, and WHO. According to EU regulations, for Pb content, 2 samples out of 16 showed values different from the set limits.

Background and Aim: Staphylococcus aureus is one of the most common causes of foodborne disease worldwide, due to the consumption of food contaminated by their toxins. This study aimed to determine the prevalence and the antimicrobial resistance of S. aureus isolated from sausages in Meknes city of Morocco. Materials and Methods: A total of 156 samples (Beef sausages, Turkey sausages, and Artisanal sausages "Merguez") were collected from different shopping sites (butchery, supermarket, street vendors, and weekly market "Souk") and used for the isolation of S. aureus. All the isolated strains were tested for their antimicrobials resistance to 16 antibiotics. Results: Our results showed the presence of S. aureus in 63 samples (40.38%). Furthermore, the antimicrobial resistance study showed that 84.13% of isolated S. aureus were resistant to streptomycin, 76.20% to tetracycline, 42.86% to ampicillin, 41.27% to doxycycline, 38.1% to penicillin G, and 19.05% to chloramphenicol with the presence of 25 different phenotypic profiles. However, all isolated strains were sensitive to oxacillin, cefoxitin, gentamicin, and vancomycin. Conclusion: The findings of this study revealed consumption of sausages as a potential risk of foodborne poisonings because of its contamination with the multi-resistant strains of S. aureus. Moreover, this contamination is related to the season, sampling sites and the origin of the raw material.

The aim of this study was to assess the virulence, antimicrobial resistance and biofilm production of Escherichia coli strains isolated from healthy broiler chickens in Western Algeria. E. coli strains (n = 18) were identified by matrix-assisted laser desorption–ionization time-of-flight mass spectrometry. Susceptibility to 10 antibiotics was determined by standard methods. Virulence and extended-spectrum β-lactamase (ESBL) genes were detected by PCR. The biofilm production was evaluated by microplate assay. All the isolates were negative for the major virulence/toxin genes tested (rfbE, fliC, eaeA, stx1), except one was stx2-positive. However, all were resistant to at least three antibiotics. Ten strains were ESBL-positive. Seven carried the β-lactamase blaTEM gene only and two co-harbored blaTEM and blaCTX-M−1 genes. One carried the blaSHV gene. Among the seven strains harboring blaTEM only, six had putative enteroaggregative genes. Two contained irp2, two contained both irp2 and astA, one contained astA and another contained aggR, astA and irp2 genes. All isolates carrying ESBL genes were non-biofilm producers, except one weak producer. The ESBL-negative isolates were moderate biofilm producers and, among them, two harbored astA, two irp2, and one aggR, astA and irp2 genes. This study highlights the spread of antimicrobial-resistant E. coli strains from healthy broiler chickens in Western Algeria.

Domestic environment, in particular, kitchen setting is a well-established source of microbial contamination. Kitchen sponges represent an important vehicle of microbial transmission and maintenance of spoilage bacteria and pathogenic strains responsible for food borne diseases. The aim of this study was to evaluate the microbial communities of 100 ‘in-use’ kitchen sponges, improving the knowledge on their role in cross-contamination in domestic environment and transmission of ESBLproducing strains. Sponges were processed for: aerobic mesophilic bacteria (AMB), Enterobacteriaceae (EB), yeasts and molds (YM), coagulase-positive staphylococci (CPS), micrococci (MCC), anaerobic sulfite reducing bacteria (ASR), and for the detection of Listeria monocytogenes, Salmonella spp. and Yersinia enterocolitica. A total of 309 enterobacteria strains were identified and then processed for ESBL (Extended Spectrum Beta Lactamase) phenotypical expression. A high contamination level of kitchen sponges was observed (mean value AMB 8.25±1.1; EB 5.89±1.2; YM 5.57±1.1; MCC 4.82±0.1 log CFU/g). Identified enterobacteria strains revealed several opportunistic and pathogenic agents such as Enterobacter cloacae (28%), Citrobacter freundii (23.3%), Cronobacter sakazakii (14.6%) and other strains in lower percentage. Listeria monocytogenes was found in only one sponge (1%). A total of 69 (22.3%) enterobacteria resulted ESBL+, with the following prevalence: P. rettgeri (50%), L. adenocarboxilata (30%), K. pneumoniae (25%), K. oxytoca (25%), C. sakazakii (20%), E. cloacae (20.7%), C. freundii (20.1%). Results confirm the potential role of kitchen sponges as vehicle for food-borne pathogens such as, C. sakazakii for the first time, infectious agents and spoilage microorganisms. The observed high contamination level and the presence of several ESBLs opportunistic pathogens, stresses the necessity to improve a proper education of the consumers on the effective treatment to reduce their microbial loads.

The effect of allyl isothiocyanate (AITC), a natural compound found in plants belonging to the family Cruciferae, on the shelf-life of fish fillets was evaluated. Preliminarily, the effectiveness of AITC was investigated in vitro against some strains of Specific Spoilage Organisms (SSOs). The inhibitory effect of AITC vapour was screened evaluating the bacterial growth in a jar. A strong inhibitory effect against the tested SSOs was observed. Successively, the shelf-life of gilthead sea bream fillets treated with AITC vapour and stored at 2°C was evaluated and compared with untreated samples. AITC inhibited the growth of SSOs effectively, and its use resulted in a shelf-life extension by ca. 8 days in treated fillets, compared to the control samples. The AITC addition in fillets yielded a distinct but pleasant flavour and contributed to a considerable reduction of fish spoilage.

n the last few years, the consumption of fish eggs has increased rapidly, finding widespread use also in mass catering. This increase has involved also those of the Peter’s fish (Zeus faber). Females of this species, by their reproductive characteristics, have highly developed gonads in different periods of the year, making the raw material easy to find. The aim of the present study was to perform a quality assessment of Zeus faber ovaries regularly commercialized for human consumption. A total number of 34 samples, divided in fresh (11) and frozen (23), were processed for microbiological characterization, parasitological and histological evaluations. Fresh and frozen samples have significant (P

ESBL and MRSA-producing bacteria in food-producing animals may contribute to increased incidences of infection in humans. This study was carried out on 38 samples obtained from 32 chickens and 6 turkey products purchased at retail outlets of Hannover (Germany) and imported from Italy. The samples included the thigh, breast fillet, gizzard, sausage, liver, heart, and roll, and were processed for the detection of ESBL producing E. coli and MRSA producing Staphylococcus aureus. Twenty-six chicken products (68.4%) of the total of poultry products analysed proved to be positive for E. coli and for phenotypical detection of ESBL. Six turkey products (100%) were positive for ESBL producing E. coli. Staphylococcus aureus was found in 4 chicken products (10.52%) that resulted positive in the detection of MRSA. Serratia spp. were reported in 4 samples that were also positive for ESBL. Thirty-three E. coli isolates from the poultry and turkey products were all resistant to at least one or more of the compounds tested. The highest resistance levels were observed, notably, against ampicillin and cefotaxim.

Three data sets concerning the behaviour of spoilage flora of fillets treated with natural preservative substances (NPS) were used to construct a new kind of mathematical predictive model. This model, unlike other ones, allows expressing the antibacterial effect of the NPS separately from the prediction of the growth rate. This approach, based on the introduction of a parameter into the predictive primary model, produced a good fitting of observed data and allowed characterising quantitatively the increase of shelf-life of fillets.

We evaluated the effects of Gymnorhynchus gigas on the freshness and hygienic quality of Lepidopus caudatus. Total Volatile Basic Nitrogen (TVB-N), Trimethylamine Nitrogen (TMA-N), as well as Specific Spoilage Organisms (SSOs) are the most important freshness indicators in fish. Our study was carried-out on 65 specimens of L. caudatus kept in ice and stored at 2°C for different period of time. The microbiological charge of SSOs recovered on a portion of parasitised muscles (MP) was compared with those recovered on portions of parasite-free muscles (M). The contents of TVB-N and TMA-N on MP, M, and G. gigas larva/ae were measured using the Conway microdiffusion method. High prevalence (72.31%) of G. gigas in the specimens of L. caudatus from the Mediterranean sea was observed. No statistically significant differences (P < 0.05) between M and MP were found during storage. However, massive infestation of G. gigas on the muscle of the silver scabbardfish could negatively influence TVB-N values, without compromising the sensorial characteristic of fish.

Essential oils are aromatic and volatile substances extracted from plants and characterized by antimicrobial activity. The aim of the present study was to evaluate the antibacterial activity (agar disc-diffusion method) of seven different bergamot essential oils (BEOs) on eight Listeria monocytogenes strains. Minimal inhibitory concentration (MIC) of most efficient BEOs was estimated. Extremely variable results for agar disc-diffusion method for L. monocytogenes strains were reported. One of the tested microorganisms resulted insensible to all the BEOs; 3 strains showed an inhibition from weak to null and the remaining 4 a variable susceptibility. Among the BEOs tested, one showed a strong activity against four pathogenic strains. Four BEOs revealed weak, moderate or null activity in all the 7 sensitive strains, while for two oils only a weak or no activity was reported. MIC values were 0.625 μL/mL for the most efficient BEO, 2.5 and 5 μL/mL for the other samples that showed moderate inhibition. Experiment results are significantly related to the strains tested (P0.01). In conclusion, we can consider BEO as a natural technological hurdle for Listeria monocytogenes in combination with other preservation strategies. Finally, this study underlines the necessity to evaluate the antimicrobial activity of EOs on a significant strains number of the same bacteria.

The present study was carried out on 21 specimens of Brama raji collected at fish markets of Sicily and Calabria between april 2011 and march 2012. The detection of total Enterobacteriaceae, Vibrio spp. and Specific Spoilage Bacteria from gills, intestine, skin and muscle during storage (336h) was carried out. 34 Vibrio spp. (rpoA+) strains were isolated from gills and skin. The subsequent identification of species by multiplex PCR (gene collagenase) allowed to establish that 33 strains were V. alginolyticus and one was V. parahaemolyticus. The anatomopathological examination of muscle tissue showed that 15 specimens (71.x4%) were positive for the presence of larvae of Gymnorhynchus gigas. The determination of TVB-N and TMA-N was made on muscle portions around the parasite, on larvae of G. gigas and on muscle portions parasite-free. The TVB-N and TMA-N contents of each sample were measured using the Conway microdiffusion method. The higher values of TVB-N (31.6 mg/100g) and TMA-N (8.5 mg/100g) were observed at 336 hours of storage. No statistically significant differences between muscle parasite-free and muscle around the parasite for TVB-N and TMA-N were observed during storage. Parasites of genus Koellikeria filicollis, Sphiriocephalus tergestinus and Anisakis spp. were also observed.

The aim of this work was to carry out an inspective survey on frozen slices of swordfish (Xiphias gladius, Linneo 1758), regularly commercialised in Messina, Sicily (Italy). 402 products were checked at retail levels; the products came from four different fishing area: 59 from the Mediterranean Sea, 155 from North-East Atlantic Ocean, 139 from the Indian Ocean, and 49 from the Pacific Ocean. Fifty-one products were sampled and carefully examined macroscopically and histologically. The histological examination was also carried out on 31 muscle portions without macroscopic alterations. 25 samples (Group A), were parasitised by larvae of Gymnorhynchus gigas or Molicola (Gymnorhynchus) horridus. The lesions described for Group B (24 samples) as well as for 31 muscle portions without macroscopic alterations were attributed, to the freezing effect. Histological and macroscopic findings on four samples suggested the presence of parasitic lesions.

The aim of this work is to evaluate the activity of R(+) limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showing a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+) limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status.

The aim of this work is to evaluate the activity of allyl isothiocyanate (AITC) against fish spoilage bacteria (specific spoilage organisms; SSOs) as well as its possible use in gilthead sea bream (Sparus aurata) fillets to extend their shelf-life. In this regard, in vitro tests are carried out in order to evaluate the inhibitory activity of AITC and its vapours on several strains of SSOs. The AITC effect on the shelflife of sea bream fillets was made by putting them in plastic trays hermetically closed with the addition AITC. Microbiological and sensorial evaluations were made on fish fillets during storage. Treated fillets maintained microbial populations at a significantly lower level compared with the control samples during storage, showing better sensorial characteristics. Therefore, the use of AITC’s vapours seems to be a new and interesting alternative way to increase fish product shelf-life.

Sushi and sashimi are traditional Japanese food, mostly consisting of raw seafood alone or in combination with rice. Eating sushi and sashimi has become popular in many countries even outside Japan. This food is not free from health risks such as ingestion of pathogenic bacteria or parasite. The aim of this study was to investigate on hygienic-sanitary quality of sushi and sashimi sold in the cities of Messina and Catania, Southern Italy. Fifty samples (38 sushi and 12 sashimi) were analysed to determinate the aerobic mesophilic bacteria (AMB), psycrophilic bacteria (PB), Enterobacteriaceae, specific spoilage organisms (SSOs), Pseudomonas spp., coagulase-positive staphylococci, micrococci, Vibrio spp., Bacillus cereus, Salmonella spp. and Listeria monocytogenes. In sushi, AMB ranged from 5.00 to 8.18 log CFU/g, PB from 4.70 to 7.13 log CFU/g, Enterobacteriaceae from 1.41 to 6.67 log CFU/g, while SSOs and Pseudomonas spp. from 3.49 to 7.72 and from 3.36 to 8.00 log CFU/g, respectively. Micrococci ranged from 3.53 to 5.03 log CFU/g and coagulase positive staphylococci were found in 16 samples (2.00 to 3.60 log CFU/g). Bacillus cereus was found in 3 samples (1.70 to 4.00 log CFU/g), while Vibrio spp. was found in 15 of the sushi samples (1.70 to 3.70 log CFU/g). In sashimi, the AMB, PB and SSOs values were higher than 7.00 log CFU/g, Pseudomonas spp. and Enterobacteriaceae were from 6.00 to 8.00 log CFU/g, while Vibrio spp. were found in six samples with means of 2.00 log CFU/g. No Salmonella spp. and Listeria monocytogenes were detected in all sushi and sashimi samples.

The ‘Nduja of Spilinga protected geographical indication (PGI) is a spreadable italian salami, obtained by using fat (50%), lean of pork (25%), chili pepper (25%) and NaCl, stuffed into natural pork casing. Its predominant flora is represented by yeasts, reaching at the end of seasoning values of 6 log CFU/g. Considering the need to enhance and protect traditional local products, it seemed interesting to carry out a characterisation of yeasts of the ‘Nduja of Spilinga PGI. A total of 127 strains of yeast isolated from samples of ‘Nduja of Spilinga PGI (79 strains from samples at different days of curing and 48 from samples of commerce) was subjected to morphological identification, hydrolysis of urea, lipolytic activity and identification with API 20C AUX, ID 32C and simplified identification systems. One hundred twenty three (96.8%) strains were attributable to the phylum Ascomycetes (urease-negative), the remaining 4 strains (3.2%) were Basidiomycetes (urease-positive). Debaryomyces hansenii and its anamorph shape, Candida famata, represented the most prevalent species (61.42 and 17.32% respectively), followed by Candida glabrata (8.66%), Pichia (Candida) guilliermondii (5.17%), Candida parapsilosis and Rhodotorula glutinis (1.57%). Candida catenulata, Criptococcus uniguttulatus, Rhodotorula minuta, Candida zeylanoides and Candida utilis were observed with 0.79%. The lipolytic activity was observed only in 10 strains of D. hansenii and in one of C. zeylanoides. Further investigation will contribute to the selection of indigenous strains that could be used for the creation of specific starter, useful to improve the process of characterisation of the ‘Nduja of Spilinga and also to guarantee its safety.

The aim of the present study was to evaluate the microbiological quality of hot beverages dispensed by vending machines (VMs). The study was carried out on 203 samples from 15 VMs located in 5 Army barracks in Messina. The samples included: water used for preparation of beverages, swab of water tank, swab of blender machine, chocolate powder, milk powder, cappuccino and chocolate drink (29 samples for each types). All samples were examined for total bacterial count (TBC), coliforms, Escherichia coli, enterococci, Pseudomonas aeruginosa, Staphylococcus aureus, Clostri - dium perfringens, Aeromonas spp., Salmonella spp. and Listeria monocytogenes. For the water samples the colony count (CC) at 22°C and at 37°C was made. The average values of CC at 22°C and at 37°C were of 10.86x10²±8.72x10² CFU/mL and of 21.72x10²±16.44x10² CFU/mL, respectively. P. aeruginosa, coliform bacteria, S. aureus, E. coli and molds were detected from water. The TBC ranged from 176 CFU/g (±275.2) for chocolate powder to 294.8±69.4 CFU/g for milk powder. S. aureus and molds were isolated from milk powder, while coliforms, E. coli and S. aureus were observed in chocolate powder. The average TBC for hot beverages ranged from 34.32x10³±97.77x10³ CFU/mL for cappuccino to 36.59x10³±10.47x104 CFU/mL for chocolate drink. Coliforms, E. coli, enterococci and molds were detected from cappuccino, while enterococci and molds were observed in chocolate drink. The microbiological characteristics of the water and powders, hygiene, and the periodic cleaning of machines, influenced the microbiological quality of the hot beverages dispensed by VMs.