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Shiga toxin producing Escherichia coli (STEC) are common etiological agents of food borne illnesses and outbreaks, most often caused by consuming contaminated beef products, followed by raw vegetables and dairy products. Patients infected with E. coli O157 are more likely hospitalized than patients infected with non-O157 STEC, making E. coli O157 an important target for microbiological interventions. We show that a cocktail of bacteriophages EP75 and EP335 effectively reduces E. coli O157 on beef, romaine lettuce, spinach, and zucchini. Treatment of contaminated beef with either 2 × 107 or 1 × 108 PFU/cm2 of bacteriophage cocktail EP75/EP335 resulted in reductions of 0.8-1.1 log10 CFU/cm2 and 0.9-1.3 log10 CFU/cm2, respectively (P less then 0.0001). Similarly, bacteriophage treatments of contaminated romaine lettuce, zucchini, or spinach showed significant (P less then 0.05) E. coli O157 reductions of 0.7-1.9 log10 CFU/cm2 (2 × 107 PFU/cm2), and 1.4-2.4 log10 CFU/cm2 (1 × 108 PFU/cm2). An E. coli O157 reduction of 0.9 log10 and 2.0 log10 was observed already 30 min after phage application of 1 × 108 PFU/cm2 on beef and romaine lettuce, respectively. These data show that bacteriophages EP75 and EP335 can be effectively used as a processing aid on beef and vegetables, and thereby can aid industry to reduce the risk of E. coli O157 food poisoning.The development of the stationary-phase, low-pH-inducible acid tolerance response (ATR) in the Salmonella contaminant of beef during the processing arises food safety concerns, because it may evoke bacterial coping mechanisms against bactericidal insults and alter gene expression that contribute to pathogen virulence. However, information on the development of the ATR and the stability (defined as the capacity to maintain the acquired acid tolerance after induction) in the Salmonella during the production and distribution of beef is limited. After adaptation overnight, ATRs in the 79 strains of Salmonella isolated from beef processing plants were investigated by comparing the log reduction in the 2-h acid challenge trials at pH 3.0. Six representative strains were selected to further estimate the effect of three factors in the incubation period on the development of the ATR, including adapted pH values (5.0, 5.4, 6.0, and 7.0), temperatures (10 °C and 37 °C), and the adaptation media (meat extract and brain ho ATR was developed when adapted in 4 °C. This emphasizes the importance of keeping a low temperature of beef throughout the supply chains of beef industry.Salmonella, a foodborne pathogen, has been frequently associated with recalls of fresh food products, including poultry meat products. Atmospheric cold plasma (ACP) is a novel non-thermal technology, which has potential to reduce pathogens in food products. This study demonstrates the synergistic interactions of food grade organic acids (i.e., lactic acid (LA) or gallic acid (GA)) and ACP to inactivate Salmonella enterica Typhimurium ATCC 13311 inoculated on polycarbonate membrane filter paper and poultry meat surface. Organic acids were used in the form of a spray to enhance dispersion on samples surface. The sequential treatment of organic acid followed by ACP synergistically reduced S. Typhimurium on poultry meat surface. Irrespective of the type of organic acid, an average reduction of more than 3.5 log CFU/cm2 in S. Typhimurium on filter paper was obtained, when a combination of 10 mM LA or GA with an ACP exposure of 30 s was tested. However, the individual treatments of LA, GA, and ACP resulted in only 0.4, 0.3, 1.2 log CFU/cm2 reduction in S. Typhimurium, respectively. On poultry meat surface, a higher level of organic acid concentration (i.e., 50 mM) in combination with 30 s ACP was required to achieve more than 2.5 log CFU/cm2 reduction in S. Typhimurium. Our investigation on inactivation mechanisms revealed that the sequential treatment of LA or GA with ACP resulted in a significantly higher level of membrane permeability and membrane lipid peroxidation in S. Typhimurium cells. Additionally, the combined treatment significantly reduced the cell metabolic activity and affected the intracellular reactive oxygen species level of S. Typhimurium. In summary, this study demonstrated the potential synergistic benefits of combining organic acids and ACP to achieve a higher level of bacterial inactivation.Multiple foodborne routes of Salmonella infection have been observed; however, the majority of the literature to date has been dominated by research into the most frequently observed reservoirs, such as chicken, beef, and pork. While less commonly observed, outbreaks of Salmonella within sheep meat still occur, requiring extensive investigation by food safety inspectors. Risk assessment models inform policy makers and investigators of the risks posed by pathogens at each stage of the food chain, and help suggest at which stages in the food chain outbreaks are likely induced. This work is the first risk assessment into the prevalence of Salmonella throughout the sheep meat food chain, from farm to fork. A Bayesian evidence-synthesis model is used, informed by data gathered from 27 individual studies - an exhaustive search of the existing literature, to express and enumerate the current understanding of Salmonella prevalence in the sheep meat food chain in the form of probabilities of colonisation throughout the food chain. The resulting posterior estimate projects that 9 (0-29 95% HDI) UK individuals are likely to fall ill with salmonellosis due to sheep meat every year. A variance-based sensitivity analysis reveals that the abattoir module is the stage of greatest bacterial proliferation, highlighting it as the most probable source of outbreaks, though not to the exclusion of other factors.Thousands of yeasts have the potential for industrial application, though many were initially considered contaminants in the beer industry. However, these organisms are currently considered important components in beers because they contribute new flavors. Non-Saccharomyces wild yeasts can be important tools in the development of new products, and the objective of this work was to obtain and characterize novel yeast isolates for their ability to produce beer. Wild yeasts were isolated from environmental samples from Olympic National Park and analyzed for their ability to ferment malt extract medium and beer wort. Six different strains were isolated, of which Moniliella megachiliensis ONP131 displayed the highest levels of attenuation during fermentations. We found that M. megachiliensis could be propagated in common yeast media, tolerated incubation temperatures of 37 °C and a pH of 2.5, and was able to grow in media containing maltose as the sole carbon source. Yeast cultivation was considerably impacted (p less then 0.05) by lactic acid, ethanol, and high concentrations of maltose, but ONP131 was tolerant to high salinity and hop acid concentrations. This is one of the first physiological characterizations of M. megachiliensis, which has potential for the production of beer and other fermented beverages.The red king crab (RKC, Paralithodes camtschaticus) and snow crab (SC, Chionoecetes opilio) are valuable decapods that can undergo live holding (LH) in onshore facilities before either live export or processing into two cooked-frozen sections (i.e., clusters). This study investigated the effect of the LH time (up to two months without feeding) and temperature (5│10 °C for RKC; 1│5 °C for SC) on the total viable psychrotrophic count (TVCP) and Pseudomonas spp. in the leg meat of cooked RKC and SC. The effect of freezing after cooking was also evaluated. The counts were determined during storage at 4 °C after cooking on the clusters undergoing either immediate refrigeration (IR) or 24-month frozen storage before refrigeration (FBR). selleck kinase inhibitor In the RKC cooked leg meat, the LH temperature significantly affected the TVCP, with LH at 10 °C leading to higher counts, while the Pseudomonas spp. levels were mainly influenced by the freezing, with lower levels in FBR samples compared to their IR counterparts. In the SC cooked leg meat, the LH conditions did not significantly affect the counts, which were instead significantly lowered by the freezing. From an industrial and commercial standpoint, it can be concluded that LH of RKC at high temperature (10 °C) led to a shorter microbial shelf-life of cooked RKC clusters, with the clusters undergoing FBR showing longer microbial shelf-life than their IR counterparts. By contrast, with the mild cooking regime applied, the LH time and temperature of SC had a lower influence on the microbial shelf-life of cooked SC clusters than that given by the choice of the storage type (IR or FBR) after cooking.The stochastic growth of homogeneous bacterial populations in the wells of a microtiter plate was studied as a function of the random initial cell number and their random individual lag times. These significantly affected the population growth in the well, while the maximum specific growth rate of the population was constant (or its variance was negligible) for each well. We showed the advantages of the mathematical assumption that a transformation of the single cell lag time, called the single cell physiological state (or, more accurately, that of the sub-population generated by the single cell) follow the Beta distribution. Simulations demonstrated what patterns would such assumption generate for the distribution of the detection times observed in the wells. An estimation procedure was developed, based on the beta-assumption, that resulted in an explicit expression for the expected value of the single cell physiological state as a function of measured "time to detection" values using turbidity experiments. The method was illustrated using laboratory data with Escherichia coli, Salmonella enterica subsp. enterica strains. The results gave a basis to quantify the difference between the studied organisms in terms of their single-cell kinetics.While Cas9-based genome editing enabled precise and sophisticated genetic perturbations in conventional and non-conventional yeast strains, its applications for food fermentations have been extremely limited. In order to improve quality and flavor of various yeast-fermented foods, we isolated and engineered a diploid or polyploid Saccharomyces cerevisiae strain (N1) which exhibits robust sugar fermentation, strong acid tolerance, and rapid gas production from Korean Nuruk. First, RGT2 and SNF3 coding for glucose sensors were deleted to increase respiration. A bread dough fermented with the N1ΔRGT2ΔSNF3 strain showed an 18% increased volume due to higher carbon dioxide production. Second, ASP3 coding for asparaginase was overexpressed and URE2 coding for a transcriptional factor of nitrogen catabolite repression (NCR) was deleted to increase asparagine consumption. When the N1ΔURE2PGPD-ASP3 strain was applied to a potato dough, asparagine was rapidly depleted in the dough, resulting in potato chips with negligible amounts of acrylamide. Third, the N1ΔURE2 strain was utilized to increase levels of the amino acids which provide a savory taste during rice wine fermentation. The above genome-edited yeast strains contain no heterologous DNA. As such, they can be used to improve fermented foods with no subjection to GM regulation.