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In recent years, there has been an increased interest in substances that could inhibit or reduce microbial growth in food products. Olive oil industry by-products, due to bioactive compounds with potential antimicrobial properties such as polyphenols, could be used in carcass treatment to enhance hygienic and quality traits. The assessment of the antimicrobial efficacy of bioactive molecules against pathogens should be determined with in vitro and in situ models since it is not possible to evaluate it directly on carcasses at the slaughterhouse. This study aimed to evaluate the effect of an olive mill wastewater polyphenolic extract against Salmonella enteritidis and Listeria monocytogenes, simulating carcass surfaces using bovine dermis samples that were experimentally contaminated with the selected pathogens. The minimum inhibitory concentration and minimum bactericidal concentration were first determined for S. enteritidis and L. monocytogenes. In situ bactericidal activity assessment was performed using 20 cm2 derma samples contaminated with 5 Log CFU/20 cm2 of S. enteritidis and L. monocytogenes in separate trials. Treatment with the polyphenolic extract was not effective for either microorganism. In order to establish the bacteriostatic activity of the polyphenolic extract, suspensions of about 2 Log CFU/20 cm2 of S. enteritidis and L. monocytogenes were used. Polyphenolic extract treatment was not effective against Salmonella, while for Listeria it allowed microbial growth to delay (around 1 Log CFU/cm2 difference at 3, 7, and 14 days between treated and control groups). Further investigations are needed to evaluate the application of polyphenolic compounds on carcass surfaces and their effects on sensory traits.

Consumption of raw or undercooked wild boar (WB) meat is considered an important risk factor for hepatitis E virus (HEV) infection in humans. The possibility of HEV contamination during the slaughtering practices may pose an additional risk. Based on these assumptions, we evaluated HEV contamination of WB meat hunted in Umbria (central Italy) during the 2022–2023 hunting season by real-time RT-PCR. Herein, we show that 10.8% of livers from slaughtered WB were positive for HEV RNA, thus providing an estimate of HEV infection in WB in the Umbria region. Then, by evaluating paired liver–muscle samples from both HEV-positive and HEV-negative animals, we found evidence of muscle HEV contamination in 33% and 14% of cases, respectively. This is the first report on the detection of HEV in WB meat in Umbria, an Italian region with diffuse WB hunting and consumption. The evidence of contamination provided by our study underscores the importance of adopting good hygienic practices in the processing stages of hunted WB carcasses to significantly reduce meat contamination and the risk posed for the final consumer.

Campylobacteriosis, a prevalent foodborne gastrointestinal infection in Europe, is primarily caused by Campylobacter jejuni and Campylobacter coli, with rising global concerns over antimicrobial resistance in these species. This study comprehensively investigates 133 human-origin Campylobacter spp. strains (102 C. jejuni and 31 C. coli) collected in Italy from 2013 to 2021. The predominant Multilocus Sequence Typing Clonal complexes (CCs) were ST-21 CC and ST-206 CC in C. jejuni and ST-828 CC in C. coli. Ciprofloxacin and tetracycline resistance, mainly attributed to GyrA (T86I) mutation and tet(O) presence, were prevalent, while erythromycin resistance was associated with 23S rRNA gene mutation (A2075G), particularly in C. coli exhibiting multidrug-resistant pattern CipTE. Notable disparities in virulence factors among strains were observed, with C. jejuni exhibiting a higher abundance compared to C. coli. Notably, specific C. jejuni sequence types, including ST-21, ST-5018, and ST-1263, demonstrated significantly elevated counts of virulence genes. This finding underscores the significance of considering both the species and strain-level variations in virulence factor profiles, shedding light on potential differences in the pathogenicity and clinical outcomes associated with distinct C. jejuni lineages. Campylobacter spp. plasmids were classified into three groups comprising pVir-like and pTet-like plasmids families, exhibiting diversity among Campylobacter spp. The study underscores the importance of early detection through Whole Genome Sequencing to identify potential emergent virulence, resistance/virulence plasmids, and new antimicrobial resistance markers. This approach provides actionable public health data, supporting the development of robust surveillance programs in Italy.

A survey was conducted from 2018 to 2023 to assess the presence of Salmonella in 280 hunted wild boar (carcasses after evisceration and skinning, N = 226; liver, N = 258; and fecal samples, N = 174). The overall prevalence was 2.86% (confidence interval 95%, 1.45–5.45%) with five positive samples detected in carcasses, three in the liver, and one in a fecal sample. This prevalence was in line with those found in nearby areas denoting a low number of positive samples. Positive animals were over 24 months of age and weighed, before skinning, 59.00 ± 9.11 Kg and no difference was detected in microbial loads between samples positive and negative for Salmonella (aerobic colony count of 4.59 and 4.66 log CFU/400 cm2, and Enterobacteriaceae count of 2.89 and 2.73 log CFU/400 cm2 (mean values) in positive and negative subjects, respectively). Salmonella Stanleyville was the most frequently isolated serotype. A semiquantitative risk assessment was conducted for the first time in game meat considering two products, meat cuts intended for cooking and fermented dry sausages. Only proper cooking can reduce the risk of ingestion of Salmonella to the minimum for consumers, whereas ready-to-eat dry sausages constitute risk products in terms of foodborne Salmonellosis (risk score of 64 out of 100).

Despite the technologies applied to food production, microbial contamination and chemical deterioration are still matters of great concern. In order to limit these phenomena, new natural approaches should be applied. In this context, the present study aimed to assess the antioxidant and anti-Clostridial effects of two different polyphenolic extracts derived from olive mill vegetation water, one liquid (LE) and one encapsulated (EE). The extracts have been preliminary characterized using Liquid Chromatography Quadrupole Time-Of Flight spectrometry. The Oxygen Radical Absorbance Capacity method was used to determine the antioxidant capacity, registering a higher value for EE compared to that for LE (3256 ± 85 and 2446 ± 13 µgTE/g, respectively). The antibacterial activity against C. perfringens, C. botulinum and C. difficile was studied by the agar well diffusion method, MIC and MBC determination and a time-kill test. The results confirm that EE and LE are able to limit microbial growth, albeit with minor effects when the phenolic compounds are encapsulated. Further studies are needed to evaluate the possible application of these extracts in food systems.

A profile of the microbial safety and hygiene of cheese in central Italy was defined based on an analysis of 1373 cheeses sampled under the Italian National Control Plan for Food Safety spanning the years 2013 to 2020 and tested according to Commission Regulation (EC) No. 2073/2005 (as amended). A total of 97.4% of cheese samples were assessed as being satisfactory for food safety criteria and 80.5% for process hygiene criteria. Staphylococcal enterotoxin was found in 2/414 samples, while Salmonella spp. and Listeria monocytogenes were detected in 15 samples out of 373 and 437, respectively. Escherichia coli and coagulase-positive staphylococci counts were found unsatisfactory in 12/61 and 17/88 cheese samples, respectively. The impact of milking species, milk thermal treatment, and cheese hardness category was considered. A statistically significant association (p < 0.05) was found between milk thermal treatment and the prevalence of coagulase-positive staphylococci and Listeria monocytogenes and between hardness and unsatisfactory levels of Escherichia coli. The data depict a contained public health risk associated with these products and confirm, at the same time, the importance of strict compliance with good hygiene practices during milk and cheese production. These results can assist in bolstering risk analysis and providing insights for food safety decision making.

Yersinia enterocolitica represents one of the main foodborne pathogens in Europe and the evaluation of possible sources of contamination and its prevalence in food is of considerable interest for risk analysis approach. The results of the search for Yersinia enterocolitica in food samples taken in Umbria region (central Italy) were evaluated during the years 2015-2018. Different types of foods were considered, both ready-to-eat (meat products, dairy products, and raw vegetables) and meat preparations to be eaten after cooking. Samples were assayed by molecular screening for the species indicator gene ompF. Screening positives were subjected to isolation and characterization by searching for specific virulence marker genes, including the ail gene responsible for invasiveness and the ystB gene for the production of enterotoxin. The total prevalence of positive samples for Yersinia enterocolitica was 16.86% with a higher percentage of positive samples in meat preparations (19.35%), followed by ready-to-eat vegetables (11.76%). Poultry meat samples had a higher prevalence than pork and beef samples. Neither positive samples were found in meat products and dairy, nor seasonality in positivity was observed. All isolated strains of Yersinia enterocolitica were biotype 1A, with absence of the ail virulence gene but presence of ystB gene. Since the strains isolated from human patients appear to be primarily biotypes that possess the ail marker, future investigations would be needed regarding the real role of biotype 1A in human disease. In this context, attention should certainly be paid to ready-to-eat vegetables and to careful cooking of meat preparations.

In this study, we describe a Salmonella enterica serovar (S.) Rissen strain with a reduced susceptibility to meropenem, isolated from a urinary infection in an 89-year-old woman in 2018 during activity surveillance in Italy (Enter-Net Italia). The genomic characteristics, pathogenicity, and antimicrobial resistance mechanisms were investigated via a genomic approach. Antimicrobial susceptibility testing revealed a “susceptible, increased exposure” phenotype to meropenem in the S. Rissen strain (4_29_19). Whole-genome sequencing (WGS) was performed using both the NovaSeq 6000 S4 PE150 XP platform (Illumina, San Diego, CA, USA) and MinION (Oxford Nanopore). The S. Rissen 4_29_19 strain harboured two plasmids: a pKpQIL-like plasmid carrying the blaKPC-3 resistance gene in a Tn4401a transposon (pKPC_4_29_19), and a ColE-like plasmid (p4_4_29_19) without resistance genes, highly prevalent among Enterobacterales. Comparative analysis revealed that the pKPC_4_29_19 plasmid was highly related to the pKpQIL reference plasmid (GU595196), with 57% coverage and 99.96% identity, but lacking a region of about 30 kb, involving the FIIK2 replicon region and the entire transfer locus, causing the loss of its ability to conjugate. To our knowledge, this is the first time that a pKpQIL-like plasmid, carrying blaKPC-3, highly diffused in Klebsiella pneumoniae strains, has been identified in a Salmonella strain in our country. The acquisition of blaKPC genes by Salmonella spp. is extremely rare, and is reported only sporadically. In zoonotic bacteria isolated from humans, the presence of a carbapenem resistance gene carried by mobile genetic elements, usually described in healthcare-associated infection bacteria, represents an important concern for public health.

The Arcobacter genus comprises a group of bacteria widely distributed in different habitats that can be spread throughout the food chain. Fluoroquinolones and aminoglycosides represent the most common antimicrobial agents used for the treatment of Arcobacter infections. However, the increasing trend of the antimicrobial resistance of this pathogen leads to treatment failures. Moreover, the test implementation and interpretation are hindered by the lack of reference protocols and standard interpretive criteria. The purpose of our study was to assess the antibiotic resistance pattern of 17 A. butzleri strains isolated in Central Italy from fresh vegetables, sushi, chicken breast, and clinical human samples to provide new and updated information about the antimicrobial resistance epidemiology of this species. Antimicrobial susceptibility testing was carried out by the European Committee on Antimicrobial Susceptibility Testing (EUCAST)’s disc diffusion method. All the strains were multidrug resistant, with 100% resistance to tetracyclines and cefotaxime (third generation cephalosporins). Some differences were noticed among the strains, according to the isolation source (clinical isolates, food of animal origin, or fresh vegetables), with a higher sensitivity to streptomycin detected only in the strains isolated from fresh vegetables. Our data, together with other epidemiological information at the national or European Union (EU) level, may contribute to developing homogeneous breakpoints. However, the high prevalence of resistance to a wide range of antimicrobial classes makes this microorganism a threat to human health and suggests that its monitoring should be considered by authorities designated for food safety.

Hazelnut shells, the main waste deriving from hazelnut processing, represent an interesting source of active molecules useful in pharmaceutics, although they have not yet been examined in depth. A hydrosoluble extract (hazelnut shell extract, HSE) was prepared by the maceration method using a hydroalcoholic solution and used as the active ingredient of patches (prepared by casting method) consisting of composites of highly deacetylated chitosan and green clay. In vitro studies showed that the formulation containing HSE is able to stimulate keratinocyte growth, which is useful for healing purposes, and to inhibit the growth of S. aureus (Log CFU/mL 0.95 vs. 8.85 of the control after 48 h); this bacterium is often responsible for wound infections and is difficult to treat by conventional antibiotics due to its antibiotic resistance. The produced patches showed suitable tensile properties that are necessary to withstand mechanical stress during both the removal from the packaging and application. The obtained results suggest that the developed patch could be a suitable product to treat wounds.

The wild boar (Sus scrofa) population in central Italy has strongly increased in the last decades. The meat of the game is characterized by high-quality value and the manufacture of food products from game meat could represent a remarkable added value for the local market promoting local gastronomic specialties and traditions. Adult animals were hunted with the waiting method and the carcasses were processed into the game processing center. Five batches of salami were produced with different amounts of wild boar meat and pork meat. The microbiological, physicochemical, rheological, and sensory evaluations were performed. The microbiological analyses indicated that the salami is safe to consume as Listeria monocytogenes and Salmonella spp. were undetectable in the end products. The Enterobacteriaceae count was below 3 log CFU.g-1 attesting to the adequacy of hygienic characteristics of the process. The chemical composition analyses showed lower lipid content in comparison to pork salami, while the rheological characteristics were equivalent among products. The sensory evaluation highlighted that the consumers’ appreciation of wild boar salami is comparable to that of traditional pork salami.

In recent years, there has been a growing interest in the use of novel antimicrobial agents able to inhibit or kill food-borne bacteria or to interrupt the onset of food spoilage. Crocus sativus L. petals, typically considered as waste obtained from saffron spice production, could be a source of natural bioactive compounds to be used as food preservatives. The purpose of this work was to investigate the antibacterial properties of two hydroalcoholicsaffron petal extracts obtained by maceration (SPEA) and by ultrasonic bath (SPEB) methods. The main polyphenols identified in both extracts were gallic and chlorogenic acids, representing almost 70% of the phenolic fraction monitored. The antibacterial activity was studied by the agar well-diffusion method, against food-borne pathogenic and spoilage bacteria. Both extracts showed activity mainly against Gram-positive bacteria, in particular those belonging to the Clostridiaceae family (C. perfringens, C. botulinum and C. difficile), with inhibition zone diameters ranging from 13 to 18 mm. The antibacterial properties against Clostridia were further analyzed, determining MIC and MBC and performing a time-kill test. SPEA showed lower MIC/MBC values (250 mg/mL) compared to SPEB (500 mg/mL), suggesting that it could be more active against the assayed strains, probably because of its higher content of gallic acid. SPEA and SPEB, tested at a concentration of 1 × MIC, showed bactericidal activity against C. perfringens, C. botulinum and C. difficile and these results suggest that saffron petals could represent a valuable natural alternative source to conventional preservatives. Further investigations are needed to evaluate possible applications in the food industry.

Ready-to-eat (RTE) meals produced and served by the catering system still represent one of the major causes of foodborne outbreaks, especially for susceptible consumers. Despite the great progress in food hygiene and safety, the systematic monitoring of microbial contamination of foodstuff is the most effective tool to ensure food safety and protect consumers’ health. The aim of this study was to perform a thorough assessment of the microbial safety and quality of meals and work surfaces of collective catering systems in central Italy, over a five-year period (2014–2018). In total 11,012 microbiological analytical determinations were performed in food matrices (80.1%) and environmental samples (19.9%). The results obtained show a low level of non-conformities ranging from 2.2% to 6.3% of total samples, concerning both hygiene and safety parameters. A decreasing trend of non-conformities during the years was also highlighted (p-value < 0.05), especially for environmental samples. This study suggests that the implementation of Good Manufacturing Practices (GMPs) and the proper definition of Hazard Analysis and Critical Control Point (HACCP) plans, combined with a thorough evaluation of microbiological monitoring, are able to ensure high levels of food safety and hygiene.

Solutions of lactic acid 2% and aromatic vinegar were investigated for microbial load reduction on the surfaces of wild boar carcasses. The animals were hunted and processed according to production specifications to obtain the best hygiene for carcasses. The solutions were sprayed on carcass surfaces after skinning, and sites of 5 × 5 cm were sampled 2 h and 48 h post-treatment, with the carcasses under refrigeration conditions. The values of the microbial loads were lower for lactic-acid-treated sites, compared with control, after both 2 and 48 h. Nonetheless, the differences in the microbial loads were only higher than 1 Log/CFU 25 cm2 for the aerobic colony count. The aromatic vinegar resulted in lower values than in controls only after 48 h for the aerobic colony count, Staphylococcus count, and Lactobacillus count, with values always below 1 Log/CFU 25 cm2. The implementation of a lactic acid solution could represent a valuable strategy to reduce microbial growth on wild boar carcasses, thus becoming a relevant critical control point in this peculiar and niche meat production process.

The mincing process of raw meat favors microbial spoilage as well as chemical and enzymatic oxidation processes. In order to limit this degradative process, preservatives are routinely added to minced meat products. The role of olive mill wastewater polyphenolic extract as a replacement for synthetic preservatives in beef burger was assessed. The antioxidant capacity of the extract experimentally added to beef burger was evaluated using the oxygen radical absorbance capacity method (ORACFL) to assess the shelf-life, while the lipid oxidation was measured by thiobarbituric reactive substance (TBAR) determination. The antimicrobial activity was assayed by means of classical methods and predictive microbiology. The experimental addition of polyphenolic extract led to 62% lower lipid oxidation and 58% higher antioxidant capacity; it also successfully modulated spoilage microbial populations with an average growth reduction of 15% on day 7. Results indicate that olive mill wastewater polyphenolic extracts could be added to raw ground beef meat to act as natural antioxidants and to modulate microbial growth.

The success of wound treatment is conditioned by the combination of both suitable active ingredients and formulation. Grape seed extract (GSE), a waste by-product obtained by grape processing, is a natural source rich in many phenolic compounds responsible for antioxidant, anti-inflammatory, and antimicrobial activities and for this reason useful to be used in a wound care product. Bioadhesive polymeric patches have been realized by combining acacia gum (AG) and polyvinylpyrrolidone (PVP). Prototypes were prepared by considering different AG/PVP ratios and the most suitable in terms of mechanical and bioadhesion properties resulted in the 9.5/1.0 ratio. This patch was loaded with GSE combined with cyclic dextrin (CD) to obtain the molecular dispersion of the active ingredient in the dried formulation. The loaded patch resulted mechanically resistant and able to release GSE by a sustained mechanism reaching concentrations able to stimulate keratinocytes’ growth, to exert both antibacterial and antioxidant activities.

Hazelnut shells represent a waste material (about 42% of the total biomass) deriving from hazelnut harvest. These are mainly used as a heating source; however, they represent an interesting source of polyphenols useful in health field. The impact on phenolic profile and concentrations of hazelnut shell extracts obtained by three extraction methods (maceration, ultrasonic bath, and high-power ultrasonic), as well as temperature, extraction time, and preventive maceration, was studied. The prepared extracts were characterized in terms of chemical composition, antioxidant and antimicrobial activities. Eighteen different phenolic compounds were identified and quantified by chemical analysis and gallic acid was the most abundant in all the extracts analyzed. Other relevant compounds were chlorogenic acid, protocatechuic acid and catechin. Preventive maceration had a positive effect on the extraction of different types of compounds regardless of the method performed. Application of the high-power ultrasonic method had different effects, either positive or negative, depending on the type of compound and extraction time. All the prepared extracts showed antioxidant activity especially those prepared by maceration, and many of them were able to inhibit the growth of both B. subtilis and B. cereus.

Salmonella in pork is still a relevant safety issue in the EU, and specific regulations are in force to control this hazard in the meat chain, in a from farm to fork perspective. In Italy, the control is mainly based on official sampling at the slaughterhouse level. The prevalence of Salmonella, and isolated serovars, was investigated during a three-year survey in small and medium slaughterhouses in central Italy. A total of 400 pig carcasses samples were collected by official authorities during the observation period. Data were also analyzed according to the year and season of sampling. The overall Salmonella prevalence in the five selected abattoirs was 13%, with no differences due to the slaughterhouses size and seasons of sampling. An increasing trend in Salmonella prevalence was registered over the years. The main serovars detected were Salmonella enterica 4,[5],12:i:- and Derby. The data emphasized that the number of contaminated carcasses is relatively high with respect to the level set by EU legislation, and equally distributed in the area, and therefore, appropriate monitoring and control strategies also need to be developed at the farm level.

Game meat production strongly differs from that of other meats, as peculiar factors present in the field and in the steps prior to transfer to a game-handling establishment can influence the hygiene of the carcasses and, therefore, of the meat. The effects of such factors were considered in hunted wild boars based on the main hygienic criteria adopted in meat processing. Environmental, animal, and hunting conditions were studied during two selective hunting seasons in Central Italy. A total of 120 hunted wild boar carcasses were sampled after the skinning process and analyzed for aerobic colony count, Enterobacteriaceae count, and Salmonella spp. isolation. The calculated mean values for aerobic colony and Enterobacteriaceae counts were 3.66 and 2.05 CFU/cm2, respectively, in line with the limits set for the meat of other ungulates by EU legislation. Salmonella spp. showed a prevalence of 2.5% (IC 95%: 1.72–3.27%). Statistical analysis of the data performed with the AIC criterion showed that the main parameter to consider for improving the hygienic level of carcasses is to reduce the time in the refrigerator before skinning, followed by hunting on cold days (

Dry (D.E.) and liquid (L.E.) extracts were prepared from flaxseeds and their application in health field was evaluated. The chemical analysis showed that D.E. is rich in the lignan secoisolariciresinol diglucoside and L.E. in unsaturated triglycerides containing linolenic acid. Mainly, D.E. showed reducing (15.73 μmol Fe2+/g) and radical scavenging capacities (5.25 mg TE/g) and ability to down-regulate the expression of the pro-inflammatory cytokines NO (IC50 = 0.136 ± 0.009 mg/mL) and IL-6 (IC50 = 0.308 ± 0.103 mg/mL), suggesting its use in wound treatment. D.E. and L.E. were active against S. pyogenes and D.E. also against S. aureus. The two extracts were combined in a novel O/W emulgel in which the water phase was viscosized using a low molecular weight and highly deacetylated chitosan (1% wt./v). The presence of this polymer in the emulgel decreased the MIC values of the extracts. In fact, MIC shifted from 0.59 mg/mL to 0.052 mg/mL for D.E. and from 0.22 mg/mL to 0.036 mg/mL for L.E., concentrations safe both for keratinocytes and macrophages. Moreover, the emulgel demonstrated to inhibit S. aureus, P. aeruginosa, S. pyogenes, E. coli, and K. pneumoniae growth (inhibition halos 24–36 mm), strains often responsible for diabetic foot ulcer infection.

Pycnogenol (PYC) is a concentrate of phenolic compounds derived from French maritime pine; its biological activity as antioxidant, anti-inflammatory and antibacterial suggests its use in the treatment of open wounds. A bioadhesive film, loaded with PYC, was prepared by casting, starting with a combination of two biopolymer acqueous solutions: xanthan gum (1% wt/wt) and sodium alginate (1.5% wt/wt), in a 2.5/7.5 (wt/wt) ratio. In both solutions, glycerol (10% wt/wt) was added as plasticizing agent. The film resulted in an adhesive capable to absorb a simulated wound fluid (~ 65% wt/wt within 1 h), therefore suitable for exuding wounds. The mechanical characterization showed that the film is deformable (elastic modulus E = 3.070 ± 0.044 MPa), suggesting adaptability to any type of surface and resistance to mechanical solicitations. PYC is released within 24 h by a sustained mechanism, achieving a maximum concentration of ~ 0.2 mg/mL, that is safe for keratinocytes, as shown by cytotoxicity studies. A concentration of 0.015 mg/mL is reached in the first 5 min after application, at which point PYC stimulates keratinocyte growth. These preliminary results suggest the use of PYC in formulations designed for topical use.

The emergence of Clostridioides difficile as the main agent of antibiotic-associated diarrhoea has raised concerns about its potential zoonotic role in different animal species. The use of antimicrobials is a major risk factor for C. difficile infection. Here, we provide data on C. difficile infection in dairy and beef calves in Umbria, a region in central Italy. This cross-sectional study focuses on prevalence, risk factors, ribotypes, toxinotypes and antimicrobial resistance profiles of circulating ribotypes. A prevalence of 19.8% (CI95%, 12–27.6%) positive farms was estimated, and the prescription of penicillins on the farms was associated with C. difficile detection (OR = 5.58). Eleven different ribotypes were found, including the ST11 sublineages RT-126 and -078, which are also commonly reported in humans. Thirteen isolates out of 17 showed resistance to at least one of clindamycin, moxifloxacin, linezolid and vancomycin. Among them, multiple-drug resistance was observed in two isolates, belonging to RT-126. Furthermore, RT-126 isolates were positive for tetracycline resistance determinants, confirming that tetracycline resistance is widespread among ST11 isolates from cattle. The administration of penicillins increased the risk of C. difficile in calves: this, together with the recovery of multi-resistant strains, strongly suggests the need for minimising antibiotic misuse on cattle farms.

In the present study, a microbiological challenge test in artificially contaminated raw milk Pecorino Umbro cheese during cheese-making was carried out. Raw ewe milk was contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes and L. monocytogenes dynamic growth were evaluated during cheese-making and storage. A significant decrease of the viable count of L. monocytogenes was observed during ripening and L. monocytogenes viable count was below the limit of quantification during storage. The results show that the product is unable to support the growth of the pathogen.