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Quantitative microbial risk assessment (QMRA) models are extensively applied to inform management of a broad range of food safety risks. Inevitably, QMRA modeling involves an element of simplification of the biological process of interest. Two features that are frequently simplified or disregarded are the pathogenicity of multiple strains of a single pathogen and consumer behavior at the household level. In this study, we developed a QMRA model with a multiple-strain approach and a consumer phase module (CPM) based on uncertainty distributions fitted from field data. We modeled exposure to staphylococcal enterotoxin A in raw milk in Lombardy; a specific enterotoxin production module was thus included. The model is adaptable and could be used to assess the risk related to other pathogens in raw milk as well as other staphylococcal enterotoxins. The multiplestrain approach, implemented as a multinomial process, allowed the inclusion of variability and uncertainty with regard to pathogenicity at the bacterial level. Data from 301 questionnaires submitted to raw milk consumers were used to obtain uncertainty distributions for the CPM. The distributions were modeled to be easily updatable with further data or evidence. The sources of uncertainty due to the multiple-strain approach and the CPM were identified, and their impact on the output was assessed by comparing specific scenarios to the baseline. When the distributions reflecting the uncertainty in consumer behavior were fixed to the 95th percentile, the risk of exposure increased up to 160 times. This reflects the importance of taking into consideration the diversity of consumers' habits at the household level and the impact that the lack of knowledge about variables in the CPM can have on the final QMRA estimates. The multiple-strain approach lends itself to use in other food matrices besides raw milk and allows the model to better capture the complexity of the real world and to be capable of geographical specificity. [ABSTRACT FROM AUTHOR]

Two quantitative risk assessment (RA) models were developed to describe the risk of salmonellosis and listeriosis linked to consumption of raw milk sold in vending machines in Italy. Exposure assessment considered the official microbiological records monitoring raw milk samples from vending machines performed by the regional veterinary authorities from 2008 to 2011, microbial growth during storage, destruction experiments, consumption frequency of raw milk, serving size, and consumption preference. Two separate RA models were developed: one for the consumption of boiled milk and the other for the consumption of raw milk. The RA models predicted no human listeriosis cases per year either in the best or worst storage conditions and with or without boiling raw milk, whereas the annual estimated cases of salmonellosis depend on the dose-response relationships used in the model, the milk storage conditions, and consumer behavior in relation to boiling raw milk or not. For example, the estimated salmonellosis cases ranged from no expected cases, assuming that the entire population boiled milk before consumption, to a maximum of 980,128 cases, assuming that the entire population drank raw milk without boiling, in the worst milk storage conditions, and with the lowest dose-response model. The findings of this study clearly show how consumer behavior could affect the probability and number of salmonellosis cases and in general, the risk of illness. Hence, the proposed RA models emphasize yet again that boiling milk before drinking is a simple yet effective tool to protect consumers against the risk of illness inherent in the consumption of raw milk. The models may also offer risk managers a useful tool to identify or implement appropriate measures to control the risk of acquiring foodborne pathogens. Quantification of the risks associated with raw milk consumption is necessary from a public health perspective. [ABSTRACT FROM AUTHOR]

All dairy farms authorized to produce and sell raw milk in a province of Northern Italy were investigated to determine the presence of Campylobacter spp., verocytotoxin-producing Escherichia coli (VTEC), Listeria monocytogenes, and Salmonella spp. in in-line milk filters and to assess their association with suspected risk factors on farms. A logistic regression model was used to analyze data collected describing the characteristics and management practices of 27 farms and the microbiological status of 378 in-line milk filters by both culture-based and molecular methods. Thermotolerant Campylobacter, VTEC, and L. monocytogenes were detected in 24 (6.45%), 32 (8.4%), and 2 (0.5%) samples, respectively. No Salmonella spp. were detected. For risk analysis, data of L. monocytogenes and Salmonella spp. were not included in the model because of the low prevalence or absence of these organisms. The univariate analysis disclosed that the presence of VTEC and/or Campylobacter spp. in milk filters was associated with lack of cleanliness of bedding, water trough, and feed trough; nonevaluation of water hardness; lack of cleanliness of milk tank; and nonapplication of forestripping. After multivariate analysis, an association was observed with inadequate cleanliness of bedding and milk tank and the nonapplication of forestripping. PCR analysis of milk filters was a rapid and sensitive method for the microbiological evaluation of herd contamination status and should be included among the registration requirements for the authorization to produce and sell raw milk. Specific control actions must be incorporated into the farmer's daily practices to ensure the low-risk production of raw milk. [ABSTRACT FROM AUTHOR]

This study involved ten enterprises producing Italian salami, 20 different samples of fermented sausages underwent challenge tests to assess and record the following parameters: time, temperature, pH, a w , and Salmonella counts. A linear regression model was used to describe the Salmonella spp. decay: at the end of the process the result of total Salmonella reduction was 0.97–5.84 Log 10 CFU/g and it was significantly associated with pH at the end of acidification/drying process, a w at the end of seasoning period, the duration of seasoning, and the caliber of salami respectively. High Pressure Processing (HPP) further reduced the Salmonella level by 2.41–5.84 Log 10 CFU/g with an efficacy that resulted inversely associated with a w of salami at the end of seasoning; the objective of 5-Log reduction was always reached in all the cases tested by the production process plus HPP. This model could be a useful tool for enterprises and Authorities to evaluate the efficacy of the processes to reduce Salmonella load for exportation to the U.S. [ABSTRACT FROM AUTHOR]

The rising prevalence of celiac disease leads to an increased demand of “gluten-free” products. A survey study on the gluten content and on the microbiological quality of “gluten-free” flour, and processing flour products, was carried out from 2010 to 2015 in Northern Italy. Overall 12,419 samples were analyzed, and 94.7% contained a gluten concentration less than 5 mg kg −1 (lower limit of detection). Only 0.1% of samples showed a gluten concentration above 80 mg kg −1 (maximum limit of detection). In the remaining 5.2%, the gluten concentration was between 5 and 80 mg kg −1 , underlining how a gluten-free diet completely devoid of gluten is unrealistic. The microbiological quality of these products was investigated. Overall, the majority of samples revealed microbial loads of less than 1 l g CFU g −1 (lower limit of detection). High levels of spoilage bacteria were found in egg-containing products. Total mesophilic bacteria were counted in all analyzed food categories with concentrations up to about 6, 8 and 9 l g CFU g −1 in dry pasta, flours and egg products respectively. Listeria monocytogenes was found only in one sample, whereas Salmonella spp. was never found. Buckwheat flour was the most frequently contaminated product by presumptive Bacillus cereus , with a prevalence of 12.5%. Also, a contamination by Coagulase-Positive Staphylococci was found during this investigation, especially in buckwheat dry pasta and flour and in egg dry pasta, with a prevalence of 54.7%. This study aimed to enhance the knowledge about the “gluten-free” products which are still poorly studied, even if their impact on the food market is increasingly considerable. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is an important food-borne pathogen causing meningitis, meningo-encephalitis and abortion. Both sporadic and epidemic human listeriosis cases are associated with the consumption of contaminated foods. To assess the potential risk to consumer health, the presence of L. monocytogenes was investigated using qualitative and quantitative methods in raw milk (bulk tank milk and milk for vending machine) collected from 2010 to 2013 in Northern Italy (Lombardy and Emilia-Romagna regions). Overall, L. monocytogenes was detected in 145 on 8716 of raw milk samples, with a prevalence of 1.66% (95% C.I. 1.4%–1.7%). The prevalence ranged from 0.52% (95% C.I. 0.3%–0.9%) in 2012 to 2.7% (95% C.I. 2.0%–3.8%) in 2013, but no trend of increase was observed in four-years of investigation. The pathogen was detected from 2.2% (95% C.I. 1.9%–2.6%) of bulk tank milk and from 0.5% (95% C.I. 0.3%–0.8%) of milk for vending machine. A significative difference (p < 0.05) of the prevalence data was observed between data collected in two different regions of Northern Italy with an higher prevalence in Lombardy. In addition to the geographical area, the L. monocytogenes presence was influenced also by the seasonal period of collection samples, with peaks in spring and autumn. These results confirm the raw milk can be a source of foodborne illness outbreaks if consumed without sanitizing treatments, but the low prevalence and the low contamination levels (more than 80% of the contaminated samples contained <10 cfu ml −l of L. monocytogenes ) proving the hygienic quality of the milk produced in Northern Italy. [ABSTRACT FROM AUTHOR]

Trade of food of animal origin between countries is carried out according to specific bilateral agreements based on the Sanitary and Phytosanitary Measures (SPS) Agreement. As specific control plans are currently in place for establishments that produce meat products to be exported to the US in order to ensure the equivalence between control systems, the Italian Ministry of Health implemented a monitoring plan in food processing establishments that export meat (n = 29), fishery (n = 5) and dairy products (n = 16) to other Third Countries. Audits of good hygiene practices for the verification of Sanitation Standard Operating Procedures (SSOPs), were carried out. For each plant, 15 environmental samples for detection of Listeria monocytogenes (L. monocytogenes) and 5 samples of ready-to-eat products for detection of L. monocytogenes and Salmonella were taken, in a total of 750 surface samples and 250 food samples. The presence of L. monocytogenes was reported in 58 environmental samples (7.7%, 95% CI 6.0–9.9), detected in 50% of food companies. L. monocytogenes was also detected in 7 food product samples (2.8%, 95% CI 1.4–5.7). Salmonella spp. was never detected. Genetic characterization of L. monocytogenes strains with pulsed-field gel electrophoresis (PFGE) was made, in one case, to correlate the origin of product contaminations to the processing environment. Genetic homogeneity among strains isolated from the same establishment was always highlighted. Audits showed that the most part of features relating to the presence and application of SSOPs were satisfied in the large majority of food companies in a proportion ranging from 88% to 100%, except the rotation of disinfectants (44% not compliant) and the presence of a list of surfaces to be regularly checked (18% not compliant). This study allowed to collect information on the microbiological safety of food companies that export from Italy to the Third Countries. Microbiological contaminations were similar to food companies that export to the US, even if L. monocytogenes detection was slightly more common. Improving cleaning and disinfection procedures and the correct application of the SSOPs will be useful to comply with the zero tolerance for L. monocytogenes requested by some Third Countries. • Export of food of animal origin is carried out according to bilateral agreements. • Lab testing and SSOPs audits were carried out in export-authorized processing plants. • The presence and application of SSOPs were satisfactory in most food companies. • Microbiological contaminations were similar to food companies that export to US. [ABSTRACT FROM AUTHOR]

A model describing Listeria innocua evolution according to process parameters of 51 Italian salami processes and HPP in 31 companies was developed. A total of 51 challenge tests were performed. During processing a L. innocua reduction of 0.34–4.32 Log10 CFU/g was observed and HPP further reduced the count of 0.48–3.47 Log10 CFU/g; an overall reduction of 1.04–5.68 is reached. PH after acidification/drying process, a w after seasoning, duration of the seasoning and caliber resulted associated (p < 0.05) with L. innocua decrease. HPP efficacy was associated (p < 0.05) with a w and pH of the product: higher the pH and a w after the acidification/drying and seasoning phases, higher resulted the L. innocua reduction after HPP. No significant association was observed between L. innocua and salt, nitrate and starter content and other characteristics of process. The model meets companies and Authorities needs and represents a useful tool to predict L. monocytogenes lethality, giving recommendations to food business operators interested in exportation to the U.S. [ABSTRACT FROM AUTHOR]