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Chicken are among the main reservoirs of Salmonella , and slaughterhouses have been identified as key sites for cross-contamination of this pathogen. This study aimed to quantify the transfer rate of Salmonella in different cross-contamination scenarios found in chicken slaughterhouses. To this end, a pool of Salmonella spp. Was inoculated onto chicken carcasses and thighs, reaching out concentrations of 2–5 log 10 CFU/g. After inoculation, carcasses and thighs were used to reproduce four cross-contamination scenarios based on industrial reality as follows: 1. Transfer of Salmonella from chicken carcasses to stainless steel and polyethylene surfaces; 2. Transfer of Salmonella between hanging chicken carcasses; 3. Transfer of Salmonella from stainless steel surfaces to chicken carcasses, and 4. Transfer of Salmonella from thighs to stainless steel and polyethylene surfaces. The results showed that the transfer rates (TR) of Salmonella on the chicken carcass to stainless steel and polyethylene were 25.77 ± 22.63% and 24.71 ± 13.93%, respectively, while the TR between hanged chicken carcasses was 5.11 ± 1.71%. When sliding carcasses through a stainless steel ramp, 41.47 ± 1.32% of the Salmonella present on the ramp adhered to the chicken carcasses, and the greater transfer seems to be linked to the wet surfaces. The transfer rates from the thighs to the stainless steel and polyethylene were 1.81 ± 0.66% and 9.0 ± 1.34%, respectively. Cross-contamination occurred regardless of the sample weight, time of contact, and amount of inoculum. [Display omitted] • A single contaminated chicken can contaminate surfaces and other chicken carcasses. • Even in low concentration Salmonella can be transferred to surfaces. • The highest Salmonella transfer occurred from the carcass wet to the stainless steel. [ABSTRACT FROM AUTHOR]

Worldwide, despite concerns about the possibility of Salmonella presence in eggs and the recommendations of regulatory agencies, soft-cooked eggs are served. Studies indicate that eggs cooked at low temperature for long times are able to inactivate Salmonella at safe levels. There are two main low cooking methods used in food services, thermocirculator (tested in a previous study) and steam oven, not yet validated. This study was undertaken to analyze the survival of Salmonella during soft-cooked eggs processing by steam oven. Five strains of Salmonella were inoculated in egg yolks and incubated at 37 °C, for 18 h, reaching 8.1 ± 0.1 log 10 CFU/g. Contaminated eggs were processed at 62 °C for 52 min in asteam oven and samples were collected for the purpose of investigating Salmonella survival. Results indicated that the egg's center temperature reached 58.7 ± 0.4 °C after 17 min and no Salmonella was detected. After 52 min of cooking, yolk remained liquid. The results of this study demonstrated that soft-cooked eggs processing by steam oven showed similar results to the processing by thermocirculator and can also be used by chefs and food processors in order to validate another way of serving soft-cooked eggs safely. • Processed eggs in steam oven at 62 °C for 52 min inactivated 8.1 log 10 CFU/g of Salmonella. • Thermal inactivation of Salmonella was well-fitted by Double Weibull model. • The 4D reduction for Salmonella was 12 min, at 62 °C. • Steam oven is an alternative to use of temperature-controlled water circulators. [ABSTRACT FROM AUTHOR]

Spaghetti alla carbonara is a traditional Italian dish, which the sauce made of raw egg yolks is heated using only the heat of cooked pasta. C oncerns about the safety of this preparation have been raised due the possibility of egg yolks be contaminated by Salmonella and the heat treatment may not be sufficient for total Salmonella inactivation. This study was undertaken to analyze the survival of Salmonella in spaghetti alla carbonara in which the only thermal processing of egg yolks was the heat transfer from the pasta. A pool of Salmonella was inoculated in egg yolks reaching 8.8 log 10 CFU/g. Contaminated egg yolks were added to the cooked spaghetti, away from the heat source. Results indicated that immediately after cooking and draining, the pasta reached 86.0 °C. After 4.5 min of contact with the egg yolks, the mean temperature of spaghetti alla carbonara decreased to lower than 60 °C. The preparation method was able to inactivate approximately 4.7 log 10 CFU/g of Salmonella and the spaghetti alla carbonara processed by this method had a creamy and silky sauce formed by yolks. Based on the results, it should be advisable the use of thermo-processed eggs to ensure the safety of this preparation. • After cooked and drained, the pasta reached a temperature of 86.0 ± 1.7 °C. • The traditional preparation method of spaghetti alla carbonara was able to inactivate 4.7 log 10 CFU/g of Salmonella. • Spaghetti alla carbonara processed by this method had a creamy and silky sauce formed by yolks. [ABSTRACT FROM AUTHOR]

Peruvian pisco sour is an alcoholic cocktail prepared with egg white in order to form a creamy texture. This drink has been served worldwide, however concerns about its safety have been raised because of the possibility of egg whites be contaminated by Salmonella. This study was undertaken to analyze the survival of Salmonella in pisco sour drink. A pool of Salmonella was inoculated in egg white and then mixed during 30 s with Quebranta pisco, syrup, lemon juice and ice cubes, reaching 6.1 ± 0.1 log 10 CFU/ml. Samples were collected to investigate the Salmonella survival. Microbiological results demonstrated that Salmonella was not detected (<100 CFU/ml) after 6 min of exposure to pisco sour (18% vol., pH 3.0), while predictive results showed that the whole population (6.1 log 10 CFU/ml) was completely inactivated after 9 min. The alcohol content associated with a low pH of pisco sour was responsible for Salmonella reduction, however, phenolic compounds present in Quebranta pisco (3.5 ± 0.3 μgGAE/ml) may also have contributed to the Salmonella inactivation. In conclusion, it is advisable to wait 9 min between preparation and consumption of pisco sour when raw egg white is used or prepare pisco sour using thermal processed egg whites. • Pisco sour drink after 6 min of exposure inactivated at least 4.1 log 10 CFU/ml of Salmonella spp. • Inactivation of Salmonella spp. was well-fitted by Geeraerd Log-Linear + Shoulder model. • The predictive results showed that Salmonella was completely inactivated in 9 min. • Alcohol content associated with a low pH was the main factor responsible for Salmonella reduction. [ABSTRACT FROM AUTHOR]

Listeriosis is a foodborne disease caused by Listeria monocytogenes (LM) and has been linked to the consumption of sliced mozzarella cheese. This study aimed to assess the LM transference during mechanical slicing of mozzarella cheese and its growth during refrigerated storage. Mozzarella cheese was contaminated with LM and 100 slices containing approximately 5 log CFU/slice were produced. Next, 100 slices of non-contaminated cheese were sliced using a contaminated blade (3.67log CFU/10 cm2). LM was quantified on the blade and slices right after slicing and after storage at 10 °C for 10 and 15 days. Results demonstrated that increasing counts of LM were transferred to the blade, comparing the first and the fifth slices (2.71 and 3.22log CFU/10 cm2, respectively, p ≤ 0.05), however, transference stabilized after the 50th slice (3.75 CFU/10 cm2). The blade transferred 1.69–2.66 log CFU/g of LM to different slices. At the end of the storage at 10 °C by 10 and 15 days, LM counts increased to 1.51 and 1.69 log CFU/g, respectively, indicating that LM population can increase if the cheese is stored for a long time. • Listeria monocytogenes (LM) can growth in mozzarella cheese slices stored at 10 °C. • Mozzarella cheese (7 log CFU/g of LM) transferred 3.67 log CFU/10 cm2 to the blade. • Blade (2.68 log CFU/cm2 of LM) transferred 1.69–2.66 log CFU/g to mozzarella cheese. [ABSTRACT FROM AUTHOR]