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Market hog lymph nodes (LNs) can contaminate carcasses with Salmonella, as well as ground and comminuted pork products. The objective of this study was to perform a qualitative and quantitative analysis of LNs from several regions and seasons in the United States to establish a Salmonella prevalence and concentration baseline. Six types of LNs (axillary, mesenteric, subiliac, tracheobronchial, superficial inguinal, prescapular), and tonsils were sampled from market hog carcasses from different regions (east, central, and west) and seasons (winter, spring, and summer/fall). Salmonella was detected and enumerated using BAX®-System-SalQuant® methods and the BAX®-System Real-Time Salmonella Assay. Salmonella prevalence (N = 4,132) was 36% for tonsils, 35% for mesenteric LN, and less than 10% for the other LN types. Of the 601 carcasses tested, 62% were positive for Salmonella, with the highest prevalence occurring during spring in the east (90.9%), and the lowest prevalence occurring during spring in the central region (26.0%). Tonsil prevalence was greatest in the eastern region during spring. Mesenteric LN prevalence was high (>20%) regardless of season or region. Salmonella prevalence in tracheobronchial, subiliac, axillary, and superficial inguinal LNs was generally greatest during the spring or fall and in the eastern region. The median SalQuant® Salmonella concentration was 2.18 log 10 Salmonella cells/sample. Median SalQuant® concentration for all other sample types fell below the limit of quantification (1 log 10 Salmonella cells/sample). This longitudinal study can be used by the pork industry for risk assessments and risk-based decision-making., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Chicken carcass and parts rinsate samples and fecal samples were collected at different stages in a commercial poultry processing facility. Microbiological analysis was conducted to determine the levels of multiple indicator microorganisms and prevalence of Salmonella . Antibiotic susceptibility testing was conducted on Salmonella isolates to determine antimicrobial resistance profiles. Whole genome sequencing was performed for tracing isolates in the processing chain, serotyping, and determining genetic features associated with virulence and antimicrobial resistance in the bacterial genome. The overall contamination rate was 55% for Salmonella . Prevalence increased by 80% in chicken parts compared with the previous processing site (postchill carcasses), suggesting possible cross-contamination during the cutting and deboning processes. The levels of indicator organisms were reduced significantly from the prescalding to the parts processing sites, by 3.22 log CFU/mL for aerobic plate count, 3.92 log CFU/mL for E. coli, 3.70 log CFU/mL for coliforms, and 3.40 log CFU/mL for Enterobacteriaceae . The most frequent resistance in Salmonella was associated with tetracycline (49 of 50, 98%) and streptomycin (43 of 50, 86%). Some Salmonella isolates featured resistance to the cephems class of antibiotics (up to 15%). Whole genome sequencing analysis of Salmonella isolates identified nine different clonal populations distributed throughout the samples taken at different stages; serotype Kentucky was the most commonly isolated. This study provides insights into microbial profiling and antibiotic-resistant strains of chicken rinsate samples during poultry processing.

Thermal inactivation of Salmonella is a critical component of the calculated thermal process to ensure the safety of cooked human and animal products. However, lethality performance standards for meat processing by-products that may harbor Salmonella have not been properly set under the actual conditions of rendering processes. The goal of this study was to evaluate the thermal inactivation parameters for Salmonella in high-fat beef trimmings as a model system for animal food products treated under simulated "worst-case scenario" commercial rendering conditions. Ground high-fat beef trimmings (50% fat) were artificially inoculated with a 10 8 CFU/g Salmonella cocktail containing human outbreak strains including the highly thermotolerant serotype Salmonella Senftenberg. The meat samples were packaged and immersed in either water or silicon oil at predetermined temperatures ranging from 60 to 121°C (from 140 to 250°F). D-values of Salmonella at each temperature were calculated from the negative inverse slope of the log CFU per gram versus time plot. The z-values were determined from the negative inverse slope of the log D versus temperature plot. The D-values in thermal death curves for low-fat (20%) content materials (between 60 and 95°C) were 2.175, 0.658, 0.237, 1.563, 0.356, 0.284, 0.264, and 0.201 min, whereas materials with 50% fat (between 100 to 121°C) were 0.277, 0.286, 0.159, 0.143, 0.137, and 0.087 min. The z-values for low- and high-temperature schedules were 43.7 and 42.9°C, respectively. Thermal lethality data for Salmonella inactivation in high-fat rendering raw materials will help animal food processors design adequate thermal processing schedules and support critical control points to ensure the safety of final beef-based rendered products.

The poultry processing industry has been undergoing a series of changes as it modifies processing practices to comply with new performance standards for chicken parts and comminuted poultry products. The regulatory approach encourages the use of intervention strategies to prevent and control foodborne pathogens in poultry products and thus improve food safety and protect human health. The present studies were conducted to evaluate the efficacy of antimicrobial interventions for reducing Salmonella on inoculated chicken parts under simulated commercial processing conditions. Chicken pieces were inoculated by immersion in a five-strain Salmonella cocktail at 6 log CFU/mL and then treated with organic acids and oxidizing agents on a commercial rinsing conveyor belt. The efficacy of spraying with six different treatments (sterile water, lactic acid, acetic acid, buffered lactic acid, acetic acid in combination with lactic acid, and peracetic acid) at two concentrations was evaluated on skin-on and skin-off chicken thighs at three application temperatures. Skinless chicken breasts were used to evaluate the antimicrobial efficacy of lactic acid and peracetic acid. The color stability of treated and untreated chicken parts was assessed after the acid interventions. The lactic acid and buffered lactic acid treatments produced the greatest reductions in Salmonella counts. Significant differences between the control and water treatments were identified for 5.11% lactic acid and 5.85% buffered lactic acid in both skin-on and skin-off chicken thighs. No significant effect of treatment temperature for skin-on chicken thighs was found. Lactic acid and peracetic acid were effective agents for eluting Salmonella cells attached to chicken breasts.

Salmonella contamination continues to be one of the major concerns for the microbiological safety of raw poultry products. Application of more than one decontamination agent as a multihurdle intervention to carcasses in a processing line might produce greater reductions than one treatment alone due to different modes of action of individual antimicrobials. In this study, all possible two-way combinations and individual applications of ε-polylysine (EPL), lauric arginate (LAE), and acidic calcium sulfate (ACS) solutions were evaluated for their effects against Salmonella enterica serovars, including Enteritidis and Typhimurium, using a sterile membrane filter model system. The combinations that provided higher Salmonella reductions were further evaluated on inoculated chicken carcasses in various concentrations applied in a sequential manner. Sequential spray applications of 300 mg of EPL per liter followed by 30% ACS and of 200 mg of LAE per liter followed by 30% ACS produced the highest Salmonella reductions on inoculated chicken carcasses, by 2.1 and 2.2 log CFU/ml, respectively. Our results indicated that these sequential spray applications of decontamination agents are effective for decreasing Salmonella contamination on poultry carcasses, but further studies are needed to determine the effectiveness of these combinations over a storage period.

The poultry industry in the United States is one of the largest in the world. Poultry consumption has significantly increase since the COVID-19 pandemic and is predicted to increase over 16% between 2021 and 2030. Two of the most significant causes of hospitalizations and death in the United States are highly related to poultry consumption. The FSIS regulates poultry processing, enforcing microbial performance standards based on Salmonella and Campylobacter prevalence in poultry processing establishments. This prevalence approach by itself is not a good indicator of food safety. More studies have shown that it is important to evaluate quantification along with prevalence, but there is not much information about poultry mapping using quantification and prevalence. In this study, enumeration and prevalence of Salmonella and Campylobacter were evaluated throughout the process at three different plants in the United States. Important locations were selected in this study to evaluate the effect of differences interventions. Even though there were high differences between the prevalences in the processes, some of the counts were not significantly different, and they were effective in maintaining pathogens at safe levels. Some of the results showed that the intervention and/or process were not well controlled, and they were not effective in controlling pathogens. This study shows that every plant environment is different, and every plant should be encouraged to implement a bio-mapping study. Quantification of pathogens leads to appropriate risk assessment, where physical and chemical interventions can be aimed at specific processing points with higher pathogen concentrations using different concentrations of overall process improvement. [ABSTRACT FROM AUTHOR]

Finalyse, a T4 bacteriophage, is a pre-harvest intervention that utilizes a combination of bacteriophages to reduce incoming Escherichia coli O157:H7 prevalence by destroying the bacteria on the hides of harvest-ready cattle entering commercial abattoirs. The objective of this study was to evaluate the efficacy of Finalyse, as a pre-harvest intervention, on the reduction in pathogens, specifically E. coli O157:H7, on the cattle hides and lairage environment to overall reduce incoming pathogen loads. Over 5 sampling events, a total of 300 composite hide samples were taken using 25 mL pre-hydrated Buffered Peptone Water (BPW) swabs, collected before and after the hide wash intervention, throughout the beginning, middle, and end of the production day (n = 10 swabs/sampling point/timepoint). A total of 171 boot swab samples were also simultaneously taken at the end of the production day by walking from the front to the back of the pen in a pre-determined 'Z' pattern to monitor the pen floor environment from 3 different locations in the lairage area. The prevalence of pathogens was analyzed using the BAX® System Real-Time PCR Assay. There were no significant reductions observed for Salmonella and/or any Shiga toxin-producing E. coli (STEC) on the hides after the bacteriophage application (p > 0.05). Escherichia coli O157:H7 and O111 hide prevalence was very low throughout the study; therefore, no further analysis was conducted. However, boot swab monitoring showed a significant reduction in E. coli O157:H7, O26, and O45 in the pen floor environment (p < 0.05). While using Finalyse as a pre-harvest intervention in the lairage areas of commercial beef processing facilities, this bacteriophage failed to reduce E. coli O157:H7 on the hides of beef cattle, as prevalence was low; however, some STECs were reduced in the lairage environment, where the bacteriophage was applied. Overall, an absolute conclusion was not formed on the effectiveness of Finalyse and its ability to reduce E. coli O157:H7 on the hides of beef cattle, as prevalence on the hides was low. [ABSTRACT FROM AUTHOR]

Bio-mapping studies conducted in pork harvest and fabrication facilities have indicated that Salmonella is prevalent and mitigations are needed to reduce the pathogen in trim and ground products. Salmonella can be isolated from the lymph nodes and can cause contamination in comminuted pork products. The objective of this study was to determine if physically removing topical and internal lymph nodes in pork products prior to grinding would result in the mitigation of Salmonella and a reduction in indicators in the final ground/comminuted products. In total, three treatment groups were assigned in a commercial pork processing facility as follows: (1) untreated control, (2) topical (surface) glands removed before grinding, and (3) topical, jowl, and internal lymph nodes and glands removed before grinding. Indicator microorganisms were determined using the BioMérieux TEMPO® system and the quantification of Salmonella was performed using the BAX® System Real-Time Salmonella SalQuant® methodology. The removal of lymph nodes located on the topical and internal surfaces and in the jowl significantly (p < 0.05) reduced the presence of Salmonella and also reduced the presence of indicator organisms according to this study. Briefly, 2.5-Log CFU/sample of Salmonella was initially observed in the trim samples, and the ground samples contained 3.8-Log CFU/sample of Salmonella. The total numbers were reduced to less than 1-Log CFU/sample in both trim and ground products. This study indicates a need for lymph node mitigation strategies beginning prior to harvest, in order to prevent contamination in further-processed pork products. [ABSTRACT FROM AUTHOR]

A bio-mapping study was conducted with the aim of creating a microbiological baseline on indicator organisms and pathogens in commercial broiler processing facilities located in a country in South America. Whole chicken carcass and wing rinses were collected from five stages of the poultry processing line: live receiving (LR), rehanger (R), post-evisceration (PE), post-chilling (PC), and wings (W). Rinses (n = 150) were enumerated using the MicroSnap™ system for total viable counts (TVC) and Enterobacteriaceae (EB), while the BAX®-System-SalQuant® and BAX®-System-CampyQuant™ were used for Salmonella and Campylobacter, respectively. TVC and EB were significantly different between stages at the processing line (p < 0.01). There was a significant reduction from LR to PC for both microbial indicators. TVC and EB counts increased significantly from PC to W. Salmonella counts at PC were significantly different from the other stages at the processing line (p = 0.03). Campylobacter counts were significantly higher than the other stages at PC (p < 0.01). The development of bio-mapping baselines with microbial indicators showed consistent reduction up to the post-chilling stage, followed by an increase at the wings sampling location. The quantification of pathogens demonstrates that prevalence analysis as a sole measurement of food safety is not sufficient to evaluate the performance of processing operations and sanitary dressing procedures in commercial processing facilities. [ABSTRACT FROM AUTHOR]

Bio-mapping studies play an important role, as the data collected can be managed and analyzed in multiple ways to look at process trends, find explanations about the effect of process changes, activate a root cause analysis for events, and even compile performance data to demonstrate to inspection authorities or auditors the effect of certain decisions made on a daily basis and their effects over time in commercial settings not only from the food safety perspective but also from the production side. This study presents an alternative analysis of bio-mapping data collected throughout several months in a commercial poultry processing operation as described in the article "Bio-Mapping Indicators and Pathogen Loads in a Commercial Broiler Processing Facility Operating with High and Low Antimicrobial Interventions". The conducted analysis identifies the processing shift effect on microbial loads, attempts to find correlation between microbial indicators data and pathogens loads, and identifies novel visualization approaches and conducts distribution analysis for microbial indicators and pathogens in a commercial poultry processing facility. From the data analyzed, a greater number of locations were statistically different between shifts under reduced levels of chemical interventions with higher means at the second shift for both indicators and pathogens levels. Minimal to negligible correlation was found when comparing aerobic counts and Enterobacteriaceae counts with Salmonella levels, with significant variability between sampling locations. Distribution analysis and visualization as a bio-map of the process resulted in a clear bimodality in reduced chemical conditions for multiple locations mostly explained by shift effect. The development and use of bio-mapping data, including proper data visualization, improves the tools needed for ongoing decision making in food safety systems. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the food safety efficacy of common antimicrobial interventions at and above required uptake levels for processing aids on the reduction of Shiga-toxin producing E. coli (STEC) and Salmonella spp. through spray and dip applications. Beef trim was inoculated with specific isolates of STEC or Salmonella strains. Trim was intervened with peracetic or lactic acid through spray or dip application. Meat rinses were serially diluted and plated following the drop dilution method; an enumerable range of 2–30 colonies was used to report results before log transformation. The combination of all treatments exhibits an average reduction rate of 0.16 LogCFU/g for STEC and Salmonella spp., suggesting that for every 1% increase in uptake there is an increase of 0.16 LogCFU/g of reduction rate. There is a statistical significance in the reduction rate of Shiga-toxin producing Escherichia coli in relation to the uptake percentage (p < 0.01). The addition of explanatory variables increases the R2 of the regression for STEC, where all the additional explanatory variables are statistically significant for reduction (p < 0.01). The addition of explanatory variables increases the R2 of the regression for Salmonella spp., but only trim type is statistically significant for reduction rate (p < 0.01). An increase in uptake percentages showed a significant increase in reduction rate of pathogens on beef trimmings. [ABSTRACT FROM AUTHOR]

The goal of this study was to develop a rapid RT-PCR enumeration method for Salmonella in pork and beef lymph nodes (LNs) utilizing BAX®-System-SalQuant® as well as to assess the performance of the methodology in comparison with existing ones. For study one: PCR curve development, pork, and beef LNs (n = 64) were trimmed, sterilized, pulverized, spiked with 0.00 to 5.00 Log CFU/LN using Salmonella Typhimurium, and then homogenized with BAX-MP media. Samples were incubated at 42 °C and tested at several time points using the BAX®-System-RT-PCR Assay for Salmonella. Cycle-Threshold values from the BAX®-System, for each Salmonella concentration were recorded and utilized for statistical analysis. For study two: Method comparison; additional pork and beef LNs (n = 52) were spiked and enumerated by (1) 3M™EB-Petrifilm™ + XLD-replica plate, (2) BAX®-System-SalQuant®, and (3) MPN. Linear-fit equations for LNs were estimated with recovery times of 6 h and a limit of quantification (LOQ) of 10 CFU/LN. Slopes and intercepts for LNs using BAX®-System-SalQuant® when compared with MPN were not significantly different (p < 0.05), while the same parameters for 3M™EB-Petrifilm™ + XLD-replica plate were significantly different (p > 0.05). The results support the capability of BAX®-System-SalQuant® to enumerate Salmonella in pork and beef LNs. This development adds support to the use of PCR-based quantification methodologies for pathogen loads in meat products. [ABSTRACT FROM AUTHOR]

The United States Department of Agriculture Food Safety and Inspection Service (USDA FSIS) does not maintain a zero-tolerance policy for Salmonella in poultry and poultry products, despite being a known food safety hazard throughout the poultry industry. In 2016, USDA FSIS established performance standards for a 52-week moving window with the maximum acceptable percent positive for comminuted turkey (325 g sample) at 13.5% (7 of 52 samples). Based upon FSIS verification sampling results from one 52-week moving window, the Salmonella prevalence for each poultry establishment in category 1 (below limit), 2 (meeting limit), or 3 (exceeding limit) are published for public viewing. Moreover, many poultry producers continue to have post-intervention samples test positive. Therefore, the use of quantification would be more valuable to determine the efficacy of process control interventions, corrective actions, and final product Log CFU/g of Salmonella to make rapid, within shift, food safety decisions. Therefore, the objectives of these studies are to develop, verify, and validate a rapid and reliable quantification method utilizing RT-PCR to enumerate Salmonella in the poultry industry from flock to final product and to utilize the method in an application study. BAX® System SalQuant® is an application of the BAX® System Real-Time PCR Assay for Salmonella to enumerate low levels of Salmonella with shortened enrichment times. Curve development encompassed inoculating poultry matrix samples at four levels with an ATCC strain of Salmonella, with three biological replicates per inoculation level, and five technical replicates being run on the BAX® System for various timepoints, gathering the data, and creating a linear-fit equation. A linear-fit equation was provided for each timepoint. The ideal timepoint, based on the statistical parameters surrounding the equation (R2 > 0.80, Log RMSE < 0.60, and enumerable range 0.00 to 4.00 Log CFU/mL (g)) that most accurately estimate Salmonella compared to most probable number (MPN), was chosen to be utilized for further studies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a quantitative baseline of indicator organisms and Salmonella by bio-mapping throughout the processing chain from harvest to final product stages within a commercial conventional design pork processing establishment. Swab samples were taken on the harvest floor at different processing steps, gambrel table, after polisher, before final rinse, after the final rinse, post snap chill, and after peroxyacetic acid (PAA) application, while 2-pound product samples were collected for trim and ground samples. The samples were subjected to analysis for indicator microorganism enumeration, Aerobic Count (AC), Enterobacteriaceae (EB), and generic Escherichia coli (EC), with the BioMérieux TEMPO®. Salmonella prevalence and enumeration was evaluated using the BAX® System Real-Time Salmonella and the SalQuant™ methodology. Microbial counts were converted to Log Colony-forming units (CFU) on a per mL, per g or per sample basis, presented as LogCFU/mL, LogCFU/g and LogCFU/sample, prior to statistical analysis. All indicator microorganisms were significantly reduced at the harvest floor (p-value < 0.001), from gambrel table to after PAA cabinet location. The reduction at harvest was 2.27, 2.46 and 2.24 LogCFU/mL for AC, EB and EC, respectively. Trim sample values fluctuated based on cut, with the highest average AC count found at neck trim (2.83 LogCFU/g). Further process samples showed the highest AC count in sausage with a mean of 5.28 LogCFU/g. EB counts in sausage (3.19 LogCFU/g) showed an evident increase, compared to the reduction observed at the end of harvest and throughout trim processing. EC counts showed a similar trend to EB counts with the highest value found in sausage links (1.60 LogCFU/g). Statistical microbial process control (SPC) parameters were also developed for each of the indicator microorganisms, using the overall mean count ( X = ), the Lower control limit (LCL) and Upper control limit (UCL) at each sampling location. For Salmonella prevalence, a total of 125/650 samples were found positive (19%). From those positive samples, 47 samples (38%) were suitable for enumeration using the BAX® System SalQuant™, the majority detected at the gambrel table location. From those enumerable samples, 60% were estimated to be between 0.97 and 1.97 LogCFU/sample, while the rest (40%) were higher within the 2.00–4.02 LogCFU/sample range. This study provides evidence for the application of indicator and pathogen quantification methodologies for food safety management in commercial pork processing operations. [ABSTRACT FROM AUTHOR]

The poultry industry in the United States has traditionally implemented non-chemical and chemical interventions against Salmonella spp. and Campylobacter spp. on the basis of experience and word-of-mouth information shared among poultry processors. The effects of individual interventions have been assessed with microbiological testing methods for Salmonella spp. and Campylobacter spp. prevalence as well as quantification of indicator organisms, such as aerobic plate counts (APC), to demonstrate efficacy. The current study evaluated the loads of both indicators and pathogens in a commercial chicken processing facility, comparing the "normal chemical", with all chemical interventions turned-on, at typical chemical concentrations set by the processing plant versus low-chemical process ("reduced chemical"), where all interventions were turned off or reduced to the minimum concentrations considered in the facility's HACCP system. Enumeration and prevalence of Salmonella spp. and Campylobacter spp. as well as indicator organisms (APC and Enterobacteriaceae—EB) enumeration were evaluated to compare both treatments throughout a 25-month sampling period. Ten locations were selected in the current bio-mapping study, including live receiving, rehanger, post eviscerator, post cropper, post neck breaker, post IOBW #1, post IOBW #2, prechilling, post chilling, and parts (wings). Statistical process control parameters for each location and processing schemes were developed for each pathogen and indicator evaluated. Despite demonstrating significant statistical differences between the normal and naked processes in Salmonella spp. counts ("normal" significantly lower counts than the "reduced" at each location except for post-eviscerator and post-cropper locations), the prevalence of Salmonella spp. after chilling is comparable on both treatments (~10%), whereas for Campylobacter spp. counts, only at the parts' location was there significant statistical difference between the "normal chemical" and the "reduced chemical". Therefore, not all chemical intervention locations show an overall impact on Salmonella spp. or Campylobacter spp., and certain interventions can be turned off to achieve the same or better microbial performance if strategic intervention locations are enhanced. [ABSTRACT FROM AUTHOR]

Foodborne salmonellosis is commonly associated with poultry and poultry products, necessitating continued development of pre- and postharvest food safety interventions and risk management strategies. Evaluation of technologies and strategies is limited by availability of cost-effective, rapid laboratory methods. The objective of this study was to evaluate a commercial qualitative PCR assay and its novel quantitative application to detect and enumerate Salmonella in poultry ceca as an analytical matrix. Ceca were collected at harvest, the contents were homogenized, and paired samples were evaluated with buffered peptone water (BPW) and BAX MP+Supplement (MPS) preenrichment broths followed by PCR screening with a BAX System Q7 PCR and by culture isolation. Additional ceca were inoculated with Salmonella to develop a standard curve for the BAX System SalQuant quantitative PCR application (QA), and estimates were obtained by the QA and most-probable-number (MPN) methods. For preenrichment media, PCR outcomes were equivalent to those of culture isolation for detecting Salmonella in ceca with 95.65 and 87.88% sensitivity and 82.00 and 100.00% specificity (P = 0.074) for BPW and MPS, respectively. However, at the sample level, BPW performed significantly worse (47.92%) than did MPS (68.75%) for overall isolation of Salmonella (P < 0.0001). After standard curve development, the mean QA estimates obtained for the inoculated samples were 1.14 (95% confidence interval [CI]: 0.62 to 1.66), 1.79 (1.50 to 2.08), 2.91 (2.65 to 3.17), and 3.76 (3.26 to 4.25) log CFU/mL for each targeted inoculation of 1.0, 2.0, 3.0, and 4.0 log CFU/mL, respectively, and were within or comparable to the 95% CI values of paired MPN estimates. These data support the use of MPS for the detection and isolation of Salmonella enterica from poultry ceca when screening with PCR and indicate that QA may be useful as an alternative tool to estimate Salmonella loads in poultry ceca, which may support preharvest food safety interventions. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of sequential applications of ε-polylysine (EPL) or lauramide arginine ethyl ester (LAE) sprays followed by an acidic calcium sulfate (ACS) spray on inoculated chicken carcasses to reduce Salmonella (Salmonella enterica serovars including Salmonella typhimurium and Salmonella enteritidis) contamination during 6 days of storage (4.4°C). Secondly, reductions of the resident microflora were studied on uninoculated chicken carcasses following the sequential application of the treatments, chilling and 10 days of storage at 4.4°C. The treatment of Salmonella inoculated carcasses with 300 mg/L EPL followed by 30% ACS (EPL300-ACS30) sprays reduced Salmonella counts initially by 1.5 log cfu/mL and then by 1.2 log cfu/mL (p<0.05) following 6 days of storage at 4.4°C. Likewise, 200 mg/L LAE followed by 30% ACS (LAE200-ACS30) treatment reduced initial Salmonella counts on poultry carcasses by 1.8, 1.4 and 1.8 log cfu/mL (p<0.05), respectively, after 0, 3, and 6 days storage. Immediately after the treatments, EPL300-ACS30 and LAE200-ACS30 both reduced Escherichia coli counts significantly by 2.6 and 2.9 log cfu/mL, respectively. EPL300-ACS30 and LAE200-ASC30 were effective in lowering psychrotroph counts by 1 log cfu/mL on day 10 when compared to the control and distilled water treatments. This study demonstrated that EPL300-ACS30 and LAE200-ACS30 were effective in reducing Salmonella on inoculated chicken carcasses both after treatment and during the storage at 4.4°C for up to 6 days. In addition, reductions in psychrotroph counts indicated that these treatments might have the potential to increase the shelf-life of poultry carcasses. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the antimicrobial efficacy of an aqueous ozone (Bio-Safe) treatment and lactic acid solutions on natural microbiota and E. coli O157:H7 and Salmonella surrogates on beef carcasses and trim in a commercial beef processing plant. For every repetition, 40 carcass and 40 trim swabs (500 cm2) were collected. Samples were taken using EZ-ReachTM swabs, and plated into aerobic plate count (APC), coliform, and E. coli PetrifilmTM for enumeration. In addition, a five-strain cocktail (MP-26) of E. coli surrogates was inoculated onto trim. For every trim surrogate repetition, 30 trim pieces were sampled after attachment and after ozone intervention. Samples were diluted and counts were determined using the TEMPO® system for E. coli enumeration. Ozone and lactic acid interventions significantly reduced (p < 0.003) bacterial counts in carcasses and trim samples. Moreover, lactic acid further reduced APC and coliforms in trim samples compared to ozone intervention (p < 0.009). In the surrogate trials, ozone significantly reduced (p < 0.001) surrogate concentration. Historical data from the plant revealed a reduction (p < 0.001) of presumptive E. coli O157:H7 in trim after a full year of ozone intervention implementation. The novel technology for ozone generation and application as an antimicrobial can become an alternative option that may also act synergistically with existing interventions, minimizing the risk of pathogens such as Salmonella and E. coli O157:H7. [ABSTRACT FROM AUTHOR]

The poultry industry in Colombia has implemented several changes and measures in chicken processing to improve sanitary operations and control pathogens' prevalence. However, there is no official in-plant microbial profile reference data currently available throughout the processing value chains. Hence, this research aimed to study the microbial profiles and the antimicrobial resistance of Salmonella isolates in three plants. In total, 300 samples were collected in seven processing sites. Prevalence of Salmonella spp. and levels of Enterobacteriaceae were assessed. Additionally, whole-genome sequencing was conducted to characterize the isolated strains genotypically. Overall, the prevalence of Salmonella spp. in each establishment was 77%, 58% and 80% for plant A, B, and C. The mean levels of Enterobacteriaceae in the chicken rinsates were 5.03, 5.74, and 6.41 log CFU/mL for plant A, B, and C. Significant reductions were identified in the counts of post-chilling rinsate samples; however, increased levels were found in chicken parts. There were six distinct Salmonella spp. clusters with the predominant sequence types ST32 and ST28. The serotypes Infantis (54%) and Paratyphi B (25%) were the most commonly identified within the processing plants with a high abundance of antimicrobial resistance genes. [ABSTRACT FROM AUTHOR]