Bio-Mapping of Microbial Indicators and Pathogen Quantitative Loads in Commercial Broiler Processing Facilities in South America

Abstract

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.

Keywords: Campylobacter spp. enumeration; Salmonella enumeration; microbial baseline; poultry bio-mapping.

Figure 1

Enterobacteriaceae and total viable counts (Log CFU/mL) at different locations throughout the poultry processing line (n = 30 rinses per location/organism). In every boxplot, the median is depicted by the horizontal line intersecting the box, while the lower and upper quartiles are denoted by the bottom and top of the box, respectively. The vertical line extending upwards represents 1.5 times the interquartile range, and the vertical line extending downwards signifies 1.5 times the lower interquartile range. ^(a–d) Boxes within aerobic counts labeled with distinct letters exhibit statistically significant differences as determined using ANOVA analysis, followed by pairwise comparisons using t-test adjusted Tukey at a significance level of p < 0.05. (x–z) Boxes within Enterobacteriaceae counts labeled with distinct letters exhibit statistically significant differences as determined using ANOVA analysis, followed by pairwise comparisons using t-test adjusted Tukey at a significance level of p < 0.05. The points represent the actual data points.

Figure 2

Salmonella prevalence (%) and counts (Log CFU/sample) at different locations throughout the poultry processing line (n = 30 rinses per location). In every boxplot, the median is depicted by the horizontal line intersecting the box, while the lower and upper quartiles are denoted by the bottom and top of the box, respectively. The vertical line extending upwards represents 1.5 times the interquartile range, and the vertical line extending downwards signifies 1.5 times the lower interquartile range. (a–b) Boxes labeled with distinct letters exhibit statistically significant differences as determined by Kruskal–Wallis analysis, followed by pairwise comparisons using Wilcoxon’s test adjusted with the Benjamin and Hochberg method, at a significance level of p < 0.05. The points represent the actual data points.

Figure 3

Campylobacter spp. prevalence (%) and counts (Log CFU/sample) at different locations throughout the poultry processing line (n = 30 rinses per location). In every boxplot, the median is depicted by the horizontal line intersecting the box, while the lower and upper quartiles are denoted by the bottom and top of the box, respectively. The vertical line extending upwards represents 1.5 times the interquartile range, and the vertical line extending downwards signifies 1.5 times the lower interquartile range. (a–d) Boxes labeled with distinct letters exhibit statistically significant differences as determined by Kruskal–Wallis analysis, followed by pairwise comparisons using Wilcoxon’s test adjusted with the Benjamin and Hochberg method, at a significance level of p < 0.05. The points represent the actual data points.

Figure 4

Visualization of the linear relationship between bacterial counts in Drop Dilution, 3M™ Petrifilm™, and TEMPO^® System compared to MicroSnap ™. (n = 32 per method).