Abstract
To confirm the usefulness of Zero Tolerance Verification at a slaughterhouse, we collected surface samples of beef carcass contaminated with animal hair (5 samples), feces (8 samples), gastrointestinal contents (6 samples), rail dust (5 samples), and foot cutter residue (5 samples). The aerobic bacteria counts (ABCs) (mean±standard deviation) of samples contaminated with animal hair, feces, gastrointestinal contents, rail dust, and foot cutter residue were 3.27 ± 1.23, 4.37 ± 1.83, 4.20 ± 0.90, 1.04 ± 0.58, and 1.70 ± 0.23 log cfu/cm2, respectively, while the Enterobacteriaceae counts (mean ± SD) of samples contaminated with animal hair, feces, and gastrointestinal contents were 1.40 ± 0.73, 2.22 ± 0.93, and 2.12 ± 1.35 log cfu/cm2, respectively. No Enterobacteriaceae were found in the samples contaminated with rail dust or foot cutter residue. There were no significant differences of ABCs and Enterobacteriaceae counts between animal hair, feces, and gastrointestinal contents. ABCs of the hair-feces-gastrointestinal contents samples was statistically higher (P＜0.05) than that of rail dust-foot cutter samples. Bacteria from the phylum Firmicutes were the most common in samples contaminated with gastrointestinal contents, whereas those from the phylum Proteobacteria were the most common in those contaminated with animal hair, rail dust, and foot cutter residue. Both phylum Firmicutes and Proteobacteria were common in fecal samples. The results suggest the necessity of removing not only gastrointestinal contents and feces but also animal hair from the surface of carcasses in slaughterhouses.
