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Clostridium species are known for their impact on animal and human health, but also for the spoilage of foodstuffs. Their spores contaminate milk and result in germination and gas production, the latter being particularly evident in the cheeses that suffer severe depreciation. To address this issue, the Primary Production Department of the IZSLER institute in Brescia, Italy conducts the Most Probable Number (MPN) method on bovine milk samples collected from Northern Italian dairies between 2004 and 2023. This approach leverages two semi-quantitative protocols, S2 and S3, to detect Clostridium species spore forms upon customer request. Here, we would like to present an a-posteriori analysis on the results of the S2 and S3 protocols. The goal of this study is to highlight the differences between these two methods and provide evidence of the actual decrease in Clostridium species in raw cow milk over a 20-year period. Our analysis shows that client demand for S2 has progressively decreased, while S3's has remained constant, and both protocols reveal a significant reduction in positives; furthermore, S3's greater sensitivity made it more responsive to environmental changes. This highlights the necessity of choosing the appropriate testing protocol that accounts for both regulatory standards and environmental factors. Overall, our findings underscore the importance of continued monitoring to manage Clostridium species contamination and ensure milk quality. [ABSTRACT FROM AUTHOR]

Over the last few decades, tick-borne encephalitis (TBE) has become a growing public health problem in Europe. The tick-borne encephalitis virus (TBEV) is a zoonotic virus that affects the central nervous system (CNS). TBEV has been detected in 27 European countries, and the rise in TBE cases is mainly due to environmental and ecological factors, and factors that increase the risk of human exposure to infected ticks. The infection via the alimentary route is the second most common means of TBEV transmission to humans. Raw milk from infected goats, sheep, or cows has been identified as a source of human food-borne infections. This study aims to gather new information on the prevalence of tick-borne encephalitis virus (TBEV) in raw goat's and cow's milk and related raw products in the Lombard Alps (Italy). This is important due to the close proximity of Lombardy to the Triveneto region, where TBE is endemic, and southern Switzerland, where numerous TBEVpositive mammals have been found. Throughout 2023, a passive monitoring plan was implemented on samples delivered for TBEV analyses from the Alpine pastures. In total, 248 specimens including raw milk, raw milk cheese, and butter were tested. This is the first monitoring of food at risk of TBEV transmission in a non-endemic region with evidence of TBEV circulation. Despite testing a wide range of dairy products, no sample tested positive for RNA-TBEV by real-time RT-PCR. Preliminary results suggest that raw milk and raw dairy products do not pose a significant risk of TBEV transmission to humans in the territory of Lombardy. [ABSTRACT FROM AUTHOR]

Water buffalo mozzarella cheese (WBMC) is a fresh pasta filata cheese produced from whole chilled buffalo milk. Although pasteurization of milk and the use of defined starter cultures are recommended, traditional technology involving the use of unpasteurized milk and natural whey cultures is still employed for WBMC production in Italy. The aim of this study were to assess the behaviour of Salmonella Typhimurium during the production of artisan water buffalo mozzarella cheese and during its shelf life under different temperature conditions. Raw milk was inoculated with S. Typhimurium and the evolution of S. Typhimurium count during production and shelf life was monitored. In artisan WBMC production technology S. Typhimurium multiplied in the curd during ripening, but its growth rate expressed in log CFU/g/h was lower than the growth rate reported by theoretical predictions. Stretching proved to be a process with good repeatability and able to reduce S. Typhimurium contamination by 5.5 Log CFU/g. The intrinsic characteristics of traditional WBMC proved to be unable to obstacolate the growth of S. Typhimurium during storage in the case of thermal abuse. Control of raw milk contamination and a proper refrigeration temperature are key factors in reducing the risk for consumers. [ABSTRACT FROM AUTHOR]

The direct sale by farmers of raw milk for human consumption has been allowed in Italy since 2004. The aim of this study was to evaluate the behaviour of selected foodborne pathogens in raw milk sold in vending machines, in field handling conditions, and during shelf-life from production to consumption. Temperature of storage of raw milk in 33 farms authorized to produce and sell raw milk were investigated from farm to vending machine delivery, together with consumer habits in one province of the Emilia-Romagna region of northern Italy. Failure to maintain appropriate low temperatures during shelf-life was recorded and 43% of consumers did not boil milk before consumption. Listeria monocytogenes, Escherichia coli O157:H7, Salmonella Typhimurium and Campylobacter jejuni strains were inoculated into raw milk samples, and the best (4°C as established by law) and worst temperature storage conditions detected (variable temperature) were simulated. Boiling tests were performed for each pathogen considered at high and low levels of contamination. Results showed an increase in L. monocytogenes in milk stored at 4°C and at variable temperatures recorded in shelf-life monitoring, an increase in E. coli O157:H7 and S. Typhimurium at variable temperatures but not at 4°C, and a decrease in C. jejuni in all storage conditions. Boiling milk is effective in making it safe for consumers. This study provides evidence that appropriate handling of raw milk, maintaining low temperatures, together with consumer education concerning boiling raw milk before consumption are key factors in preventing foodborne infections linked to raw milk consumption, and helps assess the risk of foodborne infection linked to raw milk consumption. [ABSTRACT FROM AUTHOR]

As reported on RASFF 's portal, in the first 9 months of 2016, a total of 13 “alerts/information for attention” were issued concerning the presence of Listeria monocytogenes in mould cheeses throughout Europe. This study analyzes the behaviour of L. monocytogenes in Gorgonzola cheese, a typical Italian soft blue-veined cheese, when contaminated at different time points. In the first challenge test, the pasteurized milk was contaminated and the complete cheese manufacture (cheesemaking, ripening) and shelf life was simulated. After a decrease during the first days of the cheesemaking, the pH remained constant for 35 days (5 weeks) and then it increased rapidly reaching the final values of 6.8 ± 0.02 in the core and 5.8 ± 0.4 on the rind. At the same time, the pathogen concentration decreased (about 2 log CFU/g), although during the last week a rapid pathogen growth was observed after the rise in pH values. When the cheese was stored at thermal abuse condition (8–12 °C), the pathogen concentration on the rind was 4.8 ± 0.3 log CFU/g and after 66 days (about 9 weeks) no significant difference ( p > 0.05) was observed; whereas, a growth from 5.4 ± 0.4 to 7.1 ± 0.5 log CFU/g was observed in the core. A second challenge test was performed using three batches of commercial slices of Gorgonzola cheese inoculated by L. monocytogenes and stored at 8 °C. The maximum specific growth rates (μ max , 1/h) of L. monocytogenes estimated ranged from 0.007 to 0.061. The square root model was used to predict the μ max at others temperature and to establish the time necessary to reach the European critical legal limit of 2 log CFU/g, in different storage scenarios. The predictions obtained in this study can be applied to any time-temperature profile, and in particular to the conditions to which the product is most likely to be subject in normal use, up to its final consumption. This study can be considered a valuable contribution also aimed at supporting the monitoring surveys carried out by officers of the Regional Veterinary Authority. [ABSTRACT FROM AUTHOR]

The study provides data on two cases of foodborne botulism caused by consumption of commercial vegetable products: artichoke preserve and cream of vegetable soup. By mouse bioassay, Clostridium botulinum toxin in both the suspected food samples was detected and identified as type B toxin. The detection of C. botulinum toxin in the artichoke preserve indicates an inadequate food production technology while the presence of C. botulinum toxin in the vegetable soup appeared to be related to wrong behavior on the part of the consumer and to faulty food preservation. The study confirms that an early identification and reporting of suspected botulism cases is vital in the prevention of accidental widespread outbreaks.