In the present study, the cross contamination and distribution of Escherichia coli O157:H7 was investigated in fresh-cut lettuce by simulating a commercial process at a pilot plant scale with different initial inoculum levels. A deterministic approach was used to derive a potential Food Safety Objective (FSO) for the studied pathogen. The experimental outcomes, together with literature data, were used to develop a probabilistic exposure model for E. coli O157:H7 to elucidate potential risk management metrics, i.e., Performance Objectives (POs) and a Per-formance Criterion (PC) at specific process steps within the food chain of fresh-cut leafy vegetables. The proposed FSO was estimated to be-6.0 log CFU/g for E. coli O157:H7 at consumption. The experimental results indicated that the pathogen could cross contaminate most of the samples in a lot at the different contamination levels tested (1-7 log CFU/g) resulting in a homogeneous distribution of E. coli O157:H7 in fresh-cut lettuce after processing. Based on the modelling results, the average concentration estimated as PO in unprocessed lettuce should be-5.8 log CFU/g to meet the proposed FSO. On the other hand, the PO established after washing and packaging (processed lettuce) showed a lower value, with-6.8 log CFU/g E. coli O157:H7. Reduction levels during the washing or disinfection step estimated as the PC should be > 2.9 log CFU/g. The establishment of PC for the washing step, assisted by the use of disinfection process indicators (e.g., generic E. coli), could be considered as a suitable measure to reach the FSO in fresh-cut leafy vegetables. The suggested POs and PC would help food businesses and authorities to establish safety targets and corrective actions to reduce the number of potentially contaminated lettuce lots on the market, thus reducing the number of E. coli O157:H7 infections.

According to the search for alternatives to replace antibiotics in animal production suggested in the antimicrobial resistance action plans around the world, the objective of this work was to evaluate the bactericidal effect of kaolin-silver nanomaterial for its possible inclusion as an additive in animal feed. The antibacterial activity of the C3 (kaolin-silver nanomaterial) product was tested against a wide spectrum of Gram-negative and Gram-positive bacteria (including multidrug resistant strains) by performing antibiograms, minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC), as well as growth inhibition curves against seven strains causing infections in animals. The C3 product generated inhibition halos in all the tested strains, and a higher activity against Gram-negative bacteria was found, with MBC values ranged from 7.8 µg/mL (P. aeruginosa) to 15.6 µg/mL (E. coli and Salmonella). In contrast, it was necessary to increase the concentration to 31.3 µg/mL or 250 µg/mL to eliminate 99.9% of the initial population of S. aureus ATCC 6538 and E. faecium ATCC 19434, respectively. Conversely, the inhibition growth curves showed a faster bactericidal activity against Gram-negative bacteria (between 2 and 4 h), while it took at least 24 h to observe a reduction in cell viability of S. aureus ATCC 6538. In short, this study shows that the kaolin-silver nanomaterials developed in the framework of the INTERREG POCTEFA EFA183/16/OUTBIOTICS project exhibit antibacterial activity against a wide spectrum of bacteria. However, additional studies on animal safety and environmental impact are necessary to evaluate the effectiveness of the proposed alternative in the context of One Health.

The aim of this study was to assess the routine food safety procedures carried out in catering services so as to provide a useful monitoring program for managers based on the relevant deviations detected in the observational survey and activities carried out in 15 catering services located in Navarra (region of northern Spain). The main hygiene standards, food handler practices and compliance with the HACCP system were evaluated by means of visual inspections (checklist), monitoring of critical control points (food storage and food processing temperatures, total polar compounds) and microbiological analysis of food-contact and hand-contact surfaces. While general high scores were obtained in the observational survey (73.3% above 36 points), none of the evaluated services had obtained the maximum rate of 48 points. The mayor deficiencies were related to the presence of dirty uniforms, improper hand washing or use of gloves, incorrect disinfection of vegetables and the missing records of stated critical points (temperatures and polar compounds in oil). The performed monitoring activities confirmed the safety of frying oil in all the kitchens, despite the fact that only 33% of them applied scientific methods to measure polar compounds. By contrast, holding temperatures were unsatisfactory in 77% of cold dishes and in 19% of hot meals. Despite the fact that 77% of food contact surfaces were considered acceptable (<4 CFU/cm2), high levels of total mesophilic microorganisms and Enterobacteriaceae were detected in hand-contact surfaces such as aprons and handles. The periodic visual supervision focusing on hygienic practices and the microbiological surveillance of surfaces of high risk for cross-contamination should provide valuable information for improving the knowledge, attitudes and practices of food handlers regarding food safety.

Prerequisite programs are considered the most efficient tool for a successful implementation of self-control systems to ensure food safety. The main objective of this study was to evaluate the implementation of these programs in 15 catering services located in Navarra and the Basque Country (regions in northern Spain), through on-site audits and microbiological analyses. The implementation of the prerequisite program was incomplete in 60% of the sample. The unobserved temperature control during both the storage and preparation of meals in 20% of the kitchens reveals misunderstanding in the importance of checking these critical control points. A high level of food safety and hygiene (absence of pathogens) was observed in the analyzed meals, while 27.8% of the tested surfaces exceeded the established limit for total mesophilic aerobic microorganisms (¿100 CFU/25 cm²). The group of hand-contact surfaces (oven door handles and aprons) showed the highest level of total mesophilic aerobic microorganisms and Enterobacteriaceae, and the differences observed with respect to the food-contact surfaces (work and distribution utensils) were statistically significant (P < 0.001). With regard to the food workers' hands, lower levels of microorganisms were observed in the handlers wearing gloves (that is, for Staphylococcus spp we identified 43 CFU/cm2 on average compared with 4 CFU/cm2 (P < 0.001) for those not wearing and wearing gloves, respectively). For a proper implementation of the prerequisites, it is necessary to focus on attaining a higher level of supervision of activities and better hygiene training for the food handlers, through specific activities such as informal meetings and theoretical-practical sessions adapted to the characteristics of each establishment.

Proper application of HACCP in catering services involves monitoring decisive critical points. The purpose of this study was to assess food temperatures and surface hygiene control in two catering services in Navarra (Spain) at two different time periods: the first one after implementation of the HACCP system and the second period, after the initial supervision through audits and a specific training session regarding temperatures of products and hygienic conditions of surfaces and equipment because the majority of detected nonconformities were related to these parameters. The recorded temperatures of 650 cooked food products within the first period showed that only 65.1% of the hot dishes had a temperature higher than 65 °C, in accordance with Spanish legislation, and 12.9% of them showed a risky holding temperature (<55 °C). However, the percentage of noncomplying dishes was reduced by a half after the training session (p < 0.001). Since the significant differences observed in recorded temperatures were related to the type of meal (with or without sauces) and the type of cooking procedure, a lower safe criterion for the retention of hot dishes was suggested if the temperature is continuously maintained over 55 °C until serving. With regard to cleaning and disinfection, 18.3% of the 600 analyzed surfaces did not meet the established cleaning criterion (¿100 CFU/25 cm2) in the first period, while in the second period this percentage was reduced to 13.6% in both catering businesses (p = 0.021). The dirtiest surfaces were equipment such as cutting boards and meat slicing machines (>26%) compared to utensils for distribution (12.0%). As the impact of dirty surfaces on the hygienic quality of a finished product will depend on which step was being taken during dish elaboration when equipment or utensil was used, it is suggested that more restrictive limits be established regarding utensils and equipment that are in direct contact with the finished product (¿1 CFU/cm2). Results of the study demonstrate that a specific training session on these items has improved the temperature control of prepared meals and the effectiveness of cleaning and disinfection, essentials for guaranteeing the hygienic quality of prepared foods.

Controlling Listeria monocytogenes in smoked salmon is still a challenge for food business operators. The reported lowlevels and uneven distribution of the pathogenmake it necessary to apply good sampling plans and analytical procedures in order to detect contaminated batches. However, analyses are expensive and due to current economic situations, usually only one sample per lot is checked instead of the n = 5 samples established in Regulation (EC) No 2073/2005. This work proposes the investigation of L. monocytogenes by pooling pre-enriched Half Fraser from several units from a batch (n = 6). The results obtained from a preliminary in-house validation (n = 51 pools) showed that the performance characteristics (sensitivity and specificity) are very high (N95%). This high reliability, together with reduced costs (nearly half), suggests that the wet pooling test could be a good cost-effective approach for investigating L.monocytogenes in smoked salmon. Additional research is needed before this approach can be used for other foodmatrices, such as determining the maximumnumber of units per batch that can be pooled with effective detection of L. monocytogenes.

The aim of this study was to obtain data from refrigerated ready-to-eat seafood products at retail in Spain (young eels, crabstick and smoked salmon), regarding prevalence and levels of Listeria monocytogenes, storage temperatures and the impact of transport conditions (type of bag) on the temperature of the product. The one-year surveillance period was carried out according to the EC Regulation No. 2073/2005, taking 5 units/batch and analyzing 250 samples following ISO 11290-1/A1 and ISO 11290-2/A methodologies. Low prevalence of L. monocytogenes was observed in surimi products, while 4.8% of smoked salmon samples were positive for Listeria with low levels (<10 cfu/g) and uneven pathogen distribution. A single company was responsible for 80% of the positive lots. All purchased products showed values higher than 4 C at retail and an average increase of 2.5 C or up to 6.2 C was recorded when isothermal or plastic shopping bags were used for transport, respectively. To avoid noncompliance of the Food Safety Objective for L. monocytogenes in seafood RTE products more efforts from all stakeholders are needed, with special attention so as to improve control and maintenance of refrigerators at retail and to enhance consumer education regarding food safety practices.

The evaluation of implementing the HACCP system in contract catering companies and assessment of the knowledge, attitudes and practices of the food handlers were the main objectives of this study. It was conducted in 20 companies throughout Spain, with visual inspection of facilities and food handler activities, as well as the distribution of a self-administrable questionnaire among the 105 participant catering workers. In addition, samples of surfaces and finished dishes were taken from each kitchen for microbiological evaluation. The results obtained from the questionnaires reflect extensive knowledge and correct behaviors among respondents with a middle- or high-school educational level, stability in the same workplace and positions of greater responsibility. However, the observation of hygiene practices revealed systematic incorrect procedures in 60% of the kitchens. Most observed deviations were related to the lack of HACCP training and information, the temperature of finished dishes, the storage areas and proper cleaning and disinfection. In summary, this study confirms the difficulties inherent in catering companies to effectively implement the HACCP system, such as the lack of well-trained personnel, lack of motivation or adhesion to said system on the part of the workers, and the lack of financial and economic resources to address the deficiencies in the facilities. Specific educational programs and grants are need for an adequate implementation of HACCP in this sector.