Comparison of Neck Skin Excision and Whole Carcass Rinse Sampling Methods for Microbiological Evaluation of Broiler Carcasses before and after Immersion Chilling

Abstract

Sampling protocols for detecting Salmonella on poultry differ among various countries. In the United States, the U.S. Department of Agriculture Food Safety and Inspection Service dictates that whole broiler carcasses should be rinsed with 400 ml of 1% buffered peptone water, whereas in the European Union 25-g samples composed of neck skin from three carcasses are evaluated. The purpose of this study was to evaluate a whole carcass rinse (WCR) and a neck skin excision (NS) procedure for Salmonella and Escherichia coli isolation from the same broiler carcass. Carcasses were obtained from three broiler processing plants. The skin around the neck area was aseptically removed and bagged separately from the carcass, and microbiological analysis was performed. The corresponding carcass was bagged and a WCR sample was evaluated. No significant difference (alpha </= 0.05) in Salmonella prevalence was found between the samples processed by the two methods, but both procedures produced many false-negative Salmonella results. Prechill, 37% (66 carcasses), 28% (50 carcasses), and 51% (91 carcasses) of the 180 carcasses examined were positive for Salmonella by WCR, NS, and both procedures combined, respectively. Postchill, 3% (5 carcasses), 7% (12 carcasses), and 10% (17 carcasses) of the 177 carcasses examined were positive for Salmonella by the WCR, NS, and combination of both procedures, respectively. Prechill, E. coli plus coliform counts were 3.0 and 2.6 log CFU/ml by the WCR and NS methods, respectively. Postchill, E. coli plus coliform counts were 1.7 and 1.4 log CFU/ml by the WCR and NS methods, respectively.

Escherichia coli and E nterobacteriaceae counts on poultry carcasses along the slaughterline: A systematic review and meta-analysis

“…Among 14 studies investigating this stage (Barbut et al, 2009;Berrang & Dickens, 2000;Cox et al, 2010;Fluckey et al, 2003;Gill et al, 2006;Matias et al, 2010;Oyarzabal et al, 2004;Stopforth et al, 2007;Svobodova et al, 2012;Vaidya et al, 2005;Whyte, McGill, Monahan, & Collins, 2004), 11 described a statistically significant reduction. Both the overall effect size as well as the confidence interval described a positive effect of chilling stage on counts reduction.…”

“…Since differences in sample types and methodology used to collect them can hamper the comparability of data across different studies (Cox et al, 2010), we considered three potential sources of bias: sampling method, carcass region sampled and unit of enumeration.…”

“…As regards sampling method it has been demonstrated that, although tissue excision (both skin and meat) provided the highest counts of indicator microorganisms, the rinsing method is fully comparable with tissue excision, when used for process hygiene assessment purpose (Cox et al, 2010;Gill, Badoni, Moza, Barbut, & Griffiths, 2005), while the swabbing method is less effective (Cossi, de Almeida, Dias, de Arruda Pinto, & Nero, 2012;Zhang, Ye, Xu, Zhou, & Cao, 2012). However, when bacteria such as E. coli are present at low levels on poultry carcass portions, rinsing is the most effective technique compared with excision sampling and swabbing represents a valid alternative.…”

Sampling Naturally Contaminated Broiler Carcasses for Salmonella by Three Different Methods

“…With the implementation of hazard analysis and critical control point systems in poultry processing, there has been an increase in microbiological testing, and several researchers have compared different sampling methods for Salmonella recovery from processed broiler carcasses and parts (4,7,16). Most currently used methods to detect Salmonella on processed broiler carcasses were developed to detect a positive result with an acceptable cost and ease of performance.…”

Numbers ofSalmonella recovered by sponge or low volume whole carcass rinse sampling of inoculated commercial turkey carcasses

“…In prior research evaluating the efficacy of methods for bacterial recovery, WCR was evaluated for determination of Salmonella prevalence of broiler carcasses; it compared favorably to the European Union method of neck skin excision, but both methods were shown to have high rates of false-negative results (Cox et al, 2010). The procedures used by FSIS for WCR sampling, with 30 mL subsampled from the original 400-mL rinsate, probably underestimates Salmonella prevalence on raw poultry carcasses (Fletcher, 2006).…”