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.

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.

The objective of the study was to determine the impact of antimicrobial interventions and refrigerated dark storage on the shelf-life of pork chops. Boneless pork loins (n = 36) were split and stored for 1, 14, 28, and 42 days at 2–4 °C after being treated with the following antimicrobials: water (WAT), Bovibrom 225 ppm (BB225), Bovibrom 500 ppm (BB500), Fit Fresh 3 ppm (FF3), or washing solution 750 ppm (WS750). After the end of dark storage, pork loins were further processed and sliced into chops, overwrapped in trays, and displayed for up to an additional 96 h in a retail case. Instrumental and visual color measurements as well as mesophilic and psychrotrophic aerobic bacteria, and lactic acid bacteria were measured. BB500 and FF3 performed better in inhibiting the growth of indicator bacteria under 6 logs; however, FF3 presented the best stability for color during storage. Principal component analysis clustered initial dark storage days with a* and chroma while % discoloration, hue, b* and microorganisms where clustered with longer dark storage times. In general, treatment FF3 presented the best performance, both in inhibiting microbial growth and maintaining the stability of color, thus increasing the shelf-life of pork loins.

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.

Thirty-six strip loins and top sirloin butts were collected from USDA Low Choice, “A” maturity carcasses and were assigned to freezing treatment. Subprimals were fabricated into Gluteus medius (GM) and Longissimus lumborum (LL) steaks. Beef steaks were evaluated during a 28-d retail display following freezing as a subprimal (SNGL), subprimal and steak (DBL), or never frozen (CON). Steaks were evaluated in 2 packaging films: standard/traditional rollstock packaging (ROLL) and sodium nitrite-embedded (NIT). Steak color was evaluated every 12 h instrumentally and visually every 24 h. Spoilage organisms, lipid oxidation, and purge loss analyses were conducted on days 0, 14, and 28. Trained sensory analyses were conducted on steaks without display. Color data and purge loss were analyzed using a generalized mixed linear model, while other analyses utilized a mixed model with freezing, packaging, and display as fixed effects. Redness scores of GM and LL were greatest in DBL-NIT steaks on day 0 (P < 0.05); LL in NIT had increased (P < 0.05) redness values compared with ROLL on day 28. The a* values of LL and GM were increased (P < 0.05) in NIT on day 0 and 14 compared with ROLL. Aerobic counts, Enterobacteriaceae, and lactic acid bacteria of GM and LL were increased (P < 0.05) on day 28 compared with 0. In LL steaks, there was a packaging × display interaction with increased (P < 0.05) MDA in ROLL on day 28 compared with the NIT across all timepoints. Initial juiciness was reduced in GM from SNGL compared with CON and DBL (P < 0.05). Juiciness was reduced in SNGL and DBL compared with CON of LL (P < 0.05). Freezing beef subprimals had minimal influences on descriptive sensory attributes. Markers of beef color varied little due to freezing regimen after the first day of display, while NIT improved color performance.

Poultry bio-mapping helps identify microbial contamination and process optimization opportunities such as sanitary dressing procedures, equipment adjustments, cross-contamination controls, and chemical intervention applications in commercial poultry processing operations. This study focuses on the development of a preliminary microbiological baseline of microbial indicators, including total viable counts (TVC), Enterobacteriaceae (EB), and the quantification and detection of pathogens such as Salmonella and Campylobacter spp. in four commercial broiler processing facilities in Honduras. Whole chicken and wing rinses were collected from four poultry processing plants at different locations: live receiving, rehanger, post-evisceration, post-chiller, and wings. The MicroSnap^® system was used for the enumeration of microbial indicators, the BAX^®-System-SalQuant^® was used for the quantification of Salmonella, and the BAX^®-System-CampyQuant™ was used for Campylobacter spp. Negative samples after enumeration were tested with BAX^®-System Salmonella and BAX^®-System Campylobacter for prevalence analysis, respectively. The TVC and EB counts were continuously reduced from the live receiving to the post-chiller location, presenting a statistically significant increase (p < 0.01) at the wings location. The Salmonella counts were significantly different between stages (p < 0.01). The prevalence of Salmonella was highest in the live receiving stage, with 92.50%, while that at the post-chiller stage was the lowest, at 15.38%. Campylobacter spp. counts were lower than that at the other stages at wings 1.61 Log CFU/sample; however, Campylobacter spp.’s prevalence was higher than 62.5% in all stages. Microbial bio-mapping using novel technologies suitable for mobile applications was conducted in this study to establish statistical process control parameters for microorganisms. A nationwide microbial baseline for commercial broiler processing facilities in Honduras was developed. In-country data serve as a benchmark for continuous improvement at each facility evaluated and can assist regulatory officers in the development of risk-based performance standards aimed at reducing the risk of exposure to consumers.