Italian Journal of Food Safety 2020-01-22T17:59:54+00:00 Emanuela Fusinato Open Journal Systems <p>The <strong>Italian Journal of Food Safety (IJFS)</strong> is the official journal of the <a href="" target="_blank" rel="noopener">Italian Association of Veterinary Food Hygienists (AIVI)</a>. The Journal addresses veterinary food hygienists, specialists in the food industry and other experts offering technical support and advice on food of animal origin. The <strong>Italian Journal of Food Safety</strong> publishes original research papers concerning food safety and hygiene, animal health, zoonoses and food safety, food safety economics. Reviews, editorials, technical reports, brief notes, conference proceedings, letters to the Editor, and book reviews are also welcome. Every article published in the Journal will be peer-reviewed by experts in the field and selected by members of the Editorial Board.</p> Staphylococcus aureus 2064 growth as affected by temperature and reduced water activity 2020-01-22T17:59:52+00:00 Alžbeta Medveďová Adriana Havlíková Veronika Lehotová Ľubomír Valík <p>Based on 247 growth data, the growth of <em>S. aureus</em> 2064 in dependence on temperatures (8-50°C) and <em>a<sub>w</sub></em> values (0.999-0.83) was described. Optimal values of <em>a<sub>w</sub></em> at all studied temperatures were determined by using Gibson model. Its compatibility was confirmed by several statistical indices, <em>e.g.</em> root mean square errors (<em>RMSE</em> 0.003-0.138), standard errors of prediction (%SEP 0.6-17.5). Cardinal values for <em>S. aureus</em> growth (<em>T<sub>min</sub></em>=7.7°C, <em>T<sub>opt</sub></em>=40.6°C, <em>T<sub>max</sub></em>=46.7°C, <em>a<sub>wmin</sub></em>=0.808, <em>a<sub>wopt</sub></em>=0.994, <em>μ<sub>opt</sub></em>=1.97 1/h) were determined by using CM model with indices <em>RMSE</em>=0.071, <em>SEP</em>=17.5%. Our findings can provide relevant growth information that can be used in S. aureus exposure assessment or in validation of other data regarding the growth of this opportunistic pathogen in foods.</p> 2019-12-05T08:18:21+00:00 ##submission.copyrightStatement## Occurrence and antibiogram of Listeria monocytogenes Isolates from Retail Meat Shops at Erbil City, Kurdistan Region, Iraq 2020-01-22T17:59:51+00:00 Dhary Alewy Al-Mashhadany <p><em>Listeria monocytogenes</em> is well-known globally as one of the most significant foodborne bacterial pathogens. Listeriosis may trigger life-threatening illness, such as severe sepsis, meningitis, sometimes resulting in lifelong harm and even death. This study aimed to determine the occurrence and antibiotic resistance pattern of <em>L. monocytogenes</em> in red meats sold at retail outlets in Erbil city, Kurdistan region, Iraq. Three hundred and seventy-five (375) samples were aseptically collected from retail meat shops between July and December 2018. For isolation of <em>L. monocytogenes</em>, samples were cultured on selective media and tested for their susceptibility to common antibiotics by disk diffusion assay. The results revealed that the overall occurrence of <em>L. monocytogenes</em> in red meat samples was 13.9%. Warm season was associated with increase in <em>L. monocytogenes</em> occurrence. The results of antimicrobial susceptibility testing showed that 98.1%, 94.2%, and 82.7% of isolates were resistant to Streptomycin, Gentamicin, and Ampicillin respectively. This resistance pattern of <em>L. monocytogenes</em> is critically alarming owing to the aforementioned antibiotics are the drugs of choice of treatment of listeriosis. This level of resistance requires further investigations and effective countermeasures since it may pose a public health hazard.</p> 2019-12-05T08:26:22+00:00 ##submission.copyrightStatement## A case study on the development of representative sampling procedure to determine mercury levels in a lot of tuna caught by static trap 2020-01-22T17:59:50+00:00 Pierluigi Piras Antonio Assaretti Gianuario Fiori Andrea Sanna Giannina Chessa <p>Mercury contamination in fish products, and in large pelagic predatory fish in particular, is a remarkable food safety issue that affects fish industry. A lot made up by Bluefin tunas caught at Porto Paglia − in the south-western coast of Sardinia − was subject to several sessions of fish meat official sampling, as disputable results of mercury level determination suggested a potential non-compliance to maximum allowable limit. Local competent Veterinary Service reviewed the sampling procedure introducing more rigorous details including the identification of a specific muscular portion as sampling site, after having taken into account both statutory provisions laid down by Regulation (EC) No 333/2007 and available scientific evidence on variables affecting uneven distribution of mercury across tuna carcasses. This case-study aims to provide an initial contribution in order to ensure an appropriate and representative field sampling protocol of tuna lots that are to be analysed for mercury content.</p> 2019-12-05T08:30:41+00:00 ##submission.copyrightStatement## Effect of an Italian propolis on the growth of Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus in milk and whey cheese 2020-01-22T17:59:49+00:00 Francesca Pedonese Giada Verani Beatrice Torracca Barbara Turchi Antonio Felicioli Roberta Nuvoloni <p>Propolis antimicrobial activity has been limitedly studied in food, particularly in dairy products. We studied the antimicrobial activity of an alcoholic extract of an Italian propolis in sterile skim milk, pasteurized cow’s milk, and cow’s and goat’s whey cheese (ricotta). Following the determination of the minimal inhibitory concentration on Gram+ and Gram- bacteria, the extract was employed at 2 and 5% (P2, P5), using controls with the same ethanol concentrations (E2, E5) and without any addition. In milk trials, <em>Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus</em>, and <em>Pseudomonas fluorescens</em> were tested. P2 and P5 samples registered significant decreases of Gram+ bacteria in skim milk. The same was true for P5 in cows’ milk, but only with S. aureus for P2. Ricotta was inoculated with <em>L. monocytogenes, S. aureus</em> and <em>B. cereus</em> and stored at 8.5°C. In cow’s milk ricotta, <em>L. monocytogenes</em> counts in P5 were always lower than control during the storage time, significantly so from the 14th day. In goat’s ricotta, <em>L. monocytogenes</em> counts in P5 were at least one logarithm lower than E5, whereas the extract didn’t show a significant effect on <em>S. aureus</em> and <em>B. cereus</em>. The antimicrobial activity of propolis, particularly on <em>L. monocytogenes</em>, could be employed in ready-to-eat refrigerated dairy products.</p> 2019-12-05T08:32:37+00:00 ##submission.copyrightStatement## Application of shotgun metagenomics to smoked salmon experimentally spiked: Comparison between sequencing and microbiological data using different bioinformatic approaches 2020-01-22T17:59:48+00:00 Alessandra De Cesare Chiara Oliveri Alex Lucchi Frederique Pasquali Gerardo Manfreda <p>The aims of this study were i) to evaluate the possibility to detect and possibly quantify microorganisms belonging to different domains experimentally spiked in smoked salmon at known concentrations using shotgun metagenomics; ii) to compare the sequencing results using four bioinformatic tools. The salmon was spiked with six species of bacteria, including potential foodborne pathogens, as well as <em>Cryptosporidium parvum, Saccharomyces cerevisiae</em> and <em>Bovine alphaherpesvirus</em> 1. After spiking, the salmon was kept refrigerated before DNA extraction, library preparation and sequencing at 7 Gbp in paired ends at 150 bp. The bioinformatic tools named MG-RAST, OneCodex, CosmosID and MgMapper were used for the sequence analysis and the data provided were compared using STAMP. All bacteria spiked in the salmon were identified using all bioinformatic tools. Such tools were also able to assign the higher abundances to the species <em>Propionibacterium freudenreichii</em> spiked at the highest concentration in comparison to the other bacteria. Nevertheless, different abundances were quantified for bacteria spiked in the salmon at the same cell concentration. <em>Cryptosporidium parvum</em> was detected by all bioinformatics tools, while <em>Saccharomyces cerevisiae</em> by MG-RAST only. Finally, the DNA virus was detected by CosmosID and OneCodex only. Overall, the results of this study showed that shotgun metagenomics can be applied to detect microorganisms belonging to different domains in the same food sample. Nevertheless, a direct correlation between cell concentration of each spiked microorganism and number of corresponding reads cannot be established yet.</p> 2019-12-05T08:34:45+00:00 ##submission.copyrightStatement## Occurrence of Salmonella infection and antimicrobial susceptibility for local Salmonella isolates from different sources in a cross-sectional study 2020-01-22T17:59:45+00:00 Shaymaa Abdelmalek Mona Kadry Esraa A. Elshafiee Wafy Hamed Ihab Mohamed Moussa Khalid S. Al-Maary Ayman S. Mubarak Hassan A. Hemeg Ayman Elbehiry <p>Salmonellosis is a considerable public health problem worldwide, with high economic importance in developed countries. The main purpose of this study was to determine the prevalence of Salmonella infection and antibiogram analysis of isolated strains in a cross-sectional study in Egypt 2016-2017. The study investigated twenty-eight Salmonella isolates from different areas in Egypt and different types of samples, such as human stool (9.3%), Egyptian cattle egrets and storks (28.5%) and grilled chicken from electric grills (36.6%). No isolates were detected from grilled chicken from charcoal grills or drinking water. The main Salmonella serotype detected in the isolates was <em>S. typhimurium</em> (86.5%). Molecular characterization of the invA gene by PCR was carried out and then confirmed by sequencing, and the results were submitted to GenBank. Antibiogram analysis of Egyptian isolates carried out on 9 antimicrobial discs reported that the routine regimes of treatment were not yet effective for recent new <em>Salmonella</em> generations in 2016-2017. The new isolates could be treated with levofloxacin, cefaperazone/sulbactam, chloramphenicol, imipenem or meropenem.</p> 2019-12-05T08:39:12+00:00 ##submission.copyrightStatement## Evaluation of the weight loss of raw beef cuts vacuumpackaged with two different techniques 2020-01-22T17:59:44+00:00 Simone Stella Daniela Garavaglia Giorgia Francini Valeria Viganò Cristian Bernardi Erica Tirloni <p>In the present study, 25 cuts of shank form adult cattle coming from the same slaughtering batch, were withdrawn just after manual sectioning/deboning, and each divided into two pieces (Prox and Dist) of approximately the same weight, that were vacuum packaged by using two different packaging systems: vacuum chamber machine with a bag material and a thermoforming packaging machine with top and bottom webs named BAG and THF respectively. The packed cuts were stored at 2-3°C for 20 days. The drip loss was calculated at the end of the storage as the difference between drained weight and net. Internal muscle pH and pH of the exudate present in the package and microbiological analyses (by pooling the samples) were performed at T0 and at the end of the storage. The drip loss, was significantly lower with BAG packaging: this difference was evident after 20 days of storage (average ± STD BAG <em>vs</em> THF = 1.04±0.36% vs 1.71±0.42%; P&lt;0.01). The values were, in general, low for both the packaging systems, never above 2%. Moreover, shrink bag packages are characterized by better overall pack appearance and less plastic weight per pack. Forming step reduce the thickness of thermoforming material lowering the mechanical resistance and the barrier to oxygen, on the contrary after shrinking bag materials are thickened. The pH of muscles was stable, although a slight increase was evidenced after 20 (average ± STD BAG vs THF= 5.73±0.05 <em>vs</em> 5.78±0.09; P&lt;0.01), due to the ageing of meat. The pH of the exudate was equal at T20 (average ± STD BAG vs THF = 5.34±0.20 vs 5.33±0.17). The drip loss didn’t influence the development of all the microflora; in particular LAB, that represented the main microbial population, showed a gradual increase from T0 (2.20±0.41 Log CFU/g) to T20 (average ± STD BAG vs THF= 4.76±0.29 Log CFU/g vs 4.75±0.0.15 Log CFU/g). <em>Enterobacteriaceae</em> showed an increase, if compared to the initial counts, due to the prolonged storage and the gradual growth of ephemeral microorganisms, without differences among the two series (<em>Enterobacteriaceae</em>: T0=&lt;1.7 Log CFU/g to T20 average ± STD BAG vs THF = 2.83±0.77 Log CFU/g vs 3.09±0.0.70 Log CFU/g). In conclusion, the use of the BAG system demonstrated to have an effect in reducing the drip loss of beef cuts during the refrigerated storage, with only slight influence on the other characteristics of raw meat.</p> 2019-12-05T08:41:17+00:00 ##submission.copyrightStatement## Arcobacter spp. in raw milk from vending machines in Piedmont and occurrence of virulence genes in isolates 2020-01-22T17:59:43+00:00 Amaranta Traversa Silvia Gallina Francesca Martucci Cvetelina Boteva Elisa Baioni Cristiana Maurella Laura Chiavacci Elisa Benvenuto Irene Ferrero Elena Ferrero Federica Giacometti Silvia Piva Francesco Chiesa Daniela Manila Bianchi Andrea Serraino Lucia Decastelli <p><em>Arcobacter</em> spp. has been recognized as an emerging foodborne pathogen and a hazard to human health. In the dairy chain, it has been isolated from different sources, nevertheless data on <em>Arcobacter</em> occurrence in raw milk provided by vending machines are few. This study aimed to identify potentially pathogenic <em>Arcobacter</em> spp. in raw milk intended for human consumption sold through vending machines located in Piedmont. In an 8-month period, 37 raw milk samples were collected from 24 dairy farms: 12 (32,4%) were collected directly in farm from bulk tank milk and 25 (67,6%) from vending machines. Eight (21,6%) out of the 37 milk samples and 7 (29,2%) out of the 24 dairy farms were positive for <em>Arcobacter</em> spp. by culture examination. Four (16%) out of the 25 samples from vending machines and 4 (33,3%) out of the 12 samples from bulk tank milk were positive. All 8 isolates were identified as <em>A. butzleri</em> both by MALDI-TOF MS and multiplex end-point PCR. According to the detection of virulence genes, a total of four Patho-types were highlighted: 5 isolates in P-type 1 and only one isolate for each of the P-types 2-3-4. <em>A. butzleri</em> isolates carrying encoding virulence factors genes were isolated from raw milk intended for human consumption: these findings strengthen the compulsory consumption after boiling as required by current legislation and suggest the need of enlarging the analytical investigations to other microorganisms not yet included in the food safety criteria.</p> 2019-12-05T08:47:48+00:00 ##submission.copyrightStatement## Evaluation of the efficacy of a training course in food safety addressed to food charity volunteers 2020-01-22T17:59:54+00:00 Daniela Manila Bianchi Ilaria Giorgi Fabio Zuccon Donatella De Somma Valeria D'Errico Walter Martelli Adolfo Muzzani Vilma Soncin Salvatore Collarino Daniela Adriano Lucia Decastelli <p>In Italy, the Banco Alimentare Onlus manages a network of 8,000 charitable organizations that distribute 67,000 tons of foodstuffs to 1.6 million needy persons. To provide their volunteers with the required food safety knowledge, the Banco Alimentare del Piemonte Onlus commissioned the Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta to hold training courses in food safety. Before and after each session, the participants completed a questionnaire to evaluate their knowledge on the topic of food safety. The responses were entered in a dedicated database and analyzed using STATA ver. 15.1. Comparison of the scores for each participant before and after training revealed a considerable discordance [ICC 0.06, 95% confidence interval (CI) 0.00-0.18]. Analysis of the post-training questionnaires showed that the number of questions left unanswered decreased and the number of correct answers increased. The difference between the percentage of correct and incorrect responses before and after the training course was statistically significant (P&lt;0.001). Comparison of responses to the pre- and post-training questionnaires provided the data for statistical evaluation of the efficacy of the training course.</p> 2019-12-05T08:14:02+00:00 ##submission.copyrightStatement## Microbiological analysis of the Robiola di Roccaverano cheese by means of traditional culturing methods 2020-01-22T17:59:46+00:00 Federica Biolcati Maria Teresa Bottero Alessandra Dalmasso <p>Robiola di Roccaverano is a Protected Designation of Origin soft cheese made with goat’s milk, produced in Piedmont region (Italy). The peculiarities of this cheese are: i) the use of the raw milk, ii) the addition of a Natural Milk Starter, iii) the application of traditional techniques of production and iv) the localization of the dairies in rural area. All these aspects influence the microbial flora of final product and make interesting its investigation. Samples were collected at different moment of the cheese making process and during the different seasons. In this preliminary study, the safety and the hygiene parameters of the production were evaluated. Lactic acid bacteria, moulds and yeasts involved in cheese-making process were also enumerated. Pathogens were not found in all samples and the counts of coagulase positive staphylococci were within the standard of law. The enumeration of microorganisms of technological interest demonstrated that, nevertheless the artisanal manufacturing process applied, the dairy was able to standardize the final products.</p> 2019-12-05T08:36:41+00:00 ##submission.copyrightStatement##