ARS | Publication request: ENUMERATION OF TOTAL COLIFORMS AND ESCHERICHIA COLI ON BROILER CHICKENS BY WHOLE CARCASS RINSING AND AN ALTERNATIVE SCRAPE METHOD

Submitted to: European Poultry Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 24, 2006
Publication Date: September 10, 2006
Citation: Smith, D.P., Cason Jr, J.A., Fletcher, D.L., Hannah, J.F. 2006. Enumeration of total coliforms and escherichia coli on broiler chickens by whole carcass rinsing and an alternative scrape method. European Poultry Conference Proceedings.

Technical Abstract: An experiment was conducted to compare the whole carcass rinse method (WCR) versus scraping the breast skin or back skin for enumeration of total coliforms and E. coli. In each of two replicate trials, four pre-chill broiler carcasses were collected from two different commercial processing plants. WCR was conducted on each carcass using 40 mL 1% peptone and 1 min of shaking. After the WCR, a blunt edge stainless steel blade (2.5 in wide) was used to scrape an area measuring approximately 80 square cm of the breast skin. A similar area was scraped on the back of the carcass. After scraping, the blades were placed in plastic tubes and vigorously shaken for 3 sec in 30 mL 1% peptone. One mL from the WCR rinsate and from each scrape blade tube was plated to determine total coliforms and E. coli. Results are reported as log cfu/mL. Total coliforms WCR counts (5.0) were significantly higher (P<0.05) than back scrapes (2.8), which were higher than front scrapes (2.2). E. coli WCR counts (4.5) were higher than back scrapes (2.4), which were higher than front scrapes (1.6). There were no significant differences in counts due to the plant of origin. WCR counts were higher than scrape counts due to the difference in surface area sampled. Higher back scraping counts (vs. front) suggest that either more bacteria are present on the back of the carcass or that the back is more sensitive to the scrape method as compared to the front. Keywords : whole carcass rinse, scraping, broiler chicken, coliforms, E. coli