Alsdempsey1763

la cells in liquid whole egg. Thus, the higher the intensity of the thermal treatment applied to liquid egg, the more iron would be available, a phenomenon that would be linked to the denaturation of iron and/or siderophore binding egg proteins. Further work is still required to fully elucidate why lower Salmonella initial doses lead to lower growth rates, but it can be hypothesized that this might be related to a lower amount of siderophores being released to the medium (especially salmochelin), which would also limit iron bioavailability.Pink discoloration defect can cause economic losses for cheese producers due to the impossibility to sell the defected cheese, but few knowledge is currently available on the causes of this defect. To gain more insight on the causes that lead to the formation of pink discoloration in Pecorino Toscano cheese with the Protected Designation of Origin (PDO) status, the bacterial community in defected and not defected cheese was characterized by high-throughput sequencing of bacterial 16S rRNA gene. The bacterial community in the defected cheese significantly differed compared to the control. The relative abundance of the genera Acidipropionibacterium, Enterococcus, Escherichia/Shigella, Lactobacillus, Lentilactobacillus and Propionibacterium was higher in the cheese with pink discoloration defect. The concentration of short chain fatty acids and of lactic acid in cheese was measured and a shift towards the production of propionate in the cheese with pink discoloration defect was observed. Furthermore, the possible involvement of microbially produced vitamin B12 in the formation of pink discoloration was not supported by the data, since a tendency to a lower concentration of vitamin B12 was measured in the defected cheese compared to the control.A collection of Listeria monocytogenes isolates from various food products, food processing environments and clinical sources (n = 153) were evaluated for their tolerance to acetic, lactic and propionic acids. A large variation in tolerance was observed amongst isolates under mildly acidic conditions (pH 5.3) for acetic (5-20 mM undissociated acid) and propionic acid (2-10 mM undissociated acid) but there was less variation for lactic acid (3-6 mM undissociated acid). Analysis of the isolate genome sequences for a complement of genes previously shown to have a role in acid tolerance revealed that thiT, gadT2, gadD2 and gadD3 genes were linked to higher acetic acid tolerance (P less then 0.05) while lisRK was linked to higher tolerance to propionic acid (P = 1 × 10-11). An absence of plasmid genes was also linked with isolates showing higher tolerance for all acids. Scoary GWAS analysis revealed that a total of 333, 207, and 333 genes were associated with acid tolerance for acetic, lactic, and propionic acid, respectively (P less then 0.05). However, the p-value adjusted with Bonferroni's method for multiple comparisons did not reveal any significant associations. Isolates were grouped into clonal complexes (CC) using Multi Locus Sequence Typing (MLST) and MIC values for the three acids were determined for representative strains. One complex, CC18, showed significantly higher (P ≤ 0.05) acetic and propionic acid MIC values than other groups, whereas only CC7 type isolates revealed significantly higher (P ≤ 0.001) lactic acid MIC values. The results demonstrate that MLST typing could be linked to acid tolerance phenotypic traits which is important in predicting the behaviour of L. monocytogenes in food products.The transmission of tick-borne encephalitis virus (TBEV) through food is rare, but can occur through the consumption of raw milk products from animals infected by tick bites. In 2020, France faced a TBEV outbreak linked to the consumption of unpasteurized goat cheese. The aim of this study was to develop and characterize a molecular method for the detection of TBEV in raw milk products based on the recent international standard PR ISO/DIS 16140-4. The TBEV recovery rates varied with the inoculation level and settings. The LOD50 and LOD95 of TBEV were 6.40 × 103 genome copies per g or per mL and 2.84 × 104 genome copies per g or per mL, respectively. The percentages of RT-qPCR inhibitions were lower than 75% and the murine norovirus (MNV-1), used as process control, was detected in all samples with a recovery rate higher than 1%, as recommended in ISO 15216. We conclude that the described method is appropriate to detect TBEV in raw milk products for routine diagnosis, and to assess potential health risks.Feeding dogs and cats with raw meat-based pet food is taking relevance in the recent years. The high aw of these products together with the no cooking before its consumption by the animal pose a risk due to the potential occurrence and growth of foodborne pathogens. High pressure processing (HPP) is a non-thermal emerging technology that can be used as a lethality treatment to inactivate microorganisms with a minimum impact on the sensory and nutritional traits of the product. The purpose of the present study was to evaluate the variability in pressure resistance of different strains of the relevant foodborne pathogens Salmonella spp., Escherichia coli and Listeria monocytogenes in raw pet food formulated without and with lactic acid. In general, Salmonella and L.monocytogenes strains showed a higher resistance to HPP than E. coli strains. In lactic acid acidulated formulations, the susceptibility to HPP of L. monocytogenes was markedly enhanced. The resistance to HPP was not only dependent on the microorganism but also on the strain. Thus, the selection of the proper strains should be taken into account when designing and validating the application of HPP as a control measure within the HACCP plan.The aims of this study were to characterize postbiotics, and to evaluate their antibacterial effects in-vitro and on chicken drumsticks. 7Ketocholesterol Postbiotics [Pediococcus. acidilactici (PA), Latilactobacillus sakei/Staphylococcus xylosus (LS)] exhibited strong antioxidant activity, and their total phenolic contents were found as 2952.78 ± 0.4 and 1819.44 ± 0.39 mg GAE/L, respectively (P 0.05). In conclusion, postbiotics and their combinations with natural preservatives may be an alternative approach to reduce the food-borne pathogens and to extend the shelf-life of poultry meat and meat products.Dry-aging of beef comprises the storage of carcasses and (sub)primal cuts at a low temperature and relative humidity for a prolonged period, aiming to increase the sensory quality of meat. Limited data are available on the survival and potential growth of pathogens on the surface of beef during dry-aging. Therefore, this study evaluates the changes in Salmonella, Shiga toxin-producing Escherichia coli O157H7 and Listeria monocytogenes counts during dry-aging. A mixture of pathogenic strains was inoculated on the surface of beef loins, which were stored under four different process conditions (2 °C and 6 °C × relative humidity 75 and 85% during 42 days). Salmonella and E. coli O157H7 counts significantly decreased during dry-aging. The daily reductions varied from -0.07 to -0.14 log10 CFU and from -0.09 to -0.14 log10 CFU, respectively, depending on the loin, matrix and condition. The reduction of L. monocytogenes was slower, with a maximum of -0.07 log10 CFU/day. L. monocytogenes counts increased with 1.0 log10 CFU on the lean meat of one loin with pH > 6.0 at the end of dry-aging, indicating that this pathogen can potentially grow under certain dry-aging conditions.Antibiotic Resistance is a growing concern for public health and global economy. Lactic acid bacteria (LAB) involved in the production of dairy products and commonly present in the agro-zootechnical environment can act as reservoirs of antibiotic resistance genes, acquiring or transferring them to other microorganisms. The review focuses on LAB group of dairy origin (Lactobacillus, Lactococcus, Streptococcus, Leuconostoc, Pediococcus and Weissella) and Bifidobacterium genus, considering its large use in dairy industry. We have analyzed data in the last 25 years, highlighting atypical resistance, genetic traits correlated to antibiotic resistance and their ability to be transmitted to other microorganisms; comparative analysis of resistomes was also considered. Differences were observed among wild strains isolated from different regions because of authorized antibiotic use. Commercial strains belonging to Lactobacillus, Streptococcus and Bifidobacterium currently used for industrial dairy products are frequently resistant to gentamycin, kanamycin, chloramphenicol together with tetracycline. The presence of resistant wild LAB in raw milk products has been significantly reduced as a result of worldwide restrictions on the use of antibiotics in animal husbandry. Transmissible resistances are still present in industrial cultures, despite the great effort of starter industries in the process control and the safety screening of commercial cultures.This study aims to discuss the microbial ecology of the broiler gut environment, Campylobacter prevalence across the broiler production chain with a follow-up focus on a possible mitigation strategy, based on the use of bacteriophages. Scientific literature published from the last two decades was reviewed and data were collected to establish the ranges of Campylobacter loads from different samples. Results showed that the pathogen load in the sample is likely to increase from the different stages of the production chain. Contamination of water and feed represents the most notable source of contamination during the primary production, while cross-contamination of broiler carcasses, skin, and meat occurs during the slaughter, dressing, and processing via machinery, work surfaces, water, and air partially due to the leaking of contaminated feces from visceral rupture. Knowledge gaps were identified and included a lack of studies detecting Campylobacter in broilers in most of the European countries over the last decade and a low number of studies determining the bacterial load in crates used to transport broilers to the slaughterhouse. Determining the prevalence of Campylobacter in the broiler industry will enable us to set critical control points to produce broiler flocks and meat products with a low risk of Campylobacter contamination.Salmonella is the leading cause of zoonotic foodborne illnesses worldwide and a prevalent threat to the poultry industry. For controlling contamination, the use of chemical sanitizers in combination with biological compounds (e.g., enzymes) offers a solution to reduce the chemical residues. The current study investigated the biofilm reduction effects of a food-grade enzyme-ficin-and a common sanitizer-peroxyacetic acid (PAA)-against an emerging pathogen, Salmonella enterica ser. Thompson, on plastic, eggshell, and chicken skin surfaces. Results showed that PAA could kill S. Thompson, but ficin cannot. Maximum biofilm reduction was 3.7 log CFU/cm2 from plastic after individual treatment with PAA. However, sequential treatment of ficin and PAA led to biofilm reductions of 3.2, 5.0, and 6.5 log CFU/cm2 from chicken skin, eggshell, and plastic, respectively. Fourier-transform infrared spectroscopy and microscopic analysis confirmed that ficin increased PAA action, causing biofilm matrix destruction. Moreover, the quality of the food surfaces was only altered by 12.