Title: Survival of naturally occurring Campylobacter in refrigerated and frozen rinsate from a broiler carcass Authors
Submitted to: Journal of Food Safety
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 4, 2014
Publication Date: March 4, 2014
Citation: Cox Jr, N.A., Richardson, L.J., Berrang, M.E., Rigsby, L.L., Buhr, R.J., Plumblee, J., Cray, P.J. 2014. Survival of naturally occurring Campylobacter in refrigerated and frozen rinsate from a broiler carcass. Journal of Food Safety. 34(1):76-78. Interpretive Summary: Campylobacter is the most common cause of bacterial foodborne diarrhea worldwide. Campylobacter is often found in poultry. When naturally contaminated chicken carcasses were rinsed with sterile buffer and then the resulting rinsate was stored either under refrigeration or frozen, Campylobacter cells could be recovered up to 20 months. This study shows that poultry contaminated with Campylobacter may still pose a potential health hazard after long term could storage.
Technical Abstract: The objective of this study was to determine if naturally occurring Campylobacter in a broiler carcass rinsate could survive in cold or frozen storage. Ten commercial broiler carcasses were each rinsed with 500 ml of Butterfield’s buffer and all carcasses tested positive for the presence of 104-105/ml naturally occurring Campylobacter. Each of the 10 rinse samples was subdivided into twelve 25-mL aliquots, without cryoprotectant. Six were stored at 4oC and six at -23oC. At four month intervals, one aliquot from each of the 10 rinse samples was taken from each storage temperature and tested by direct streaking (DS) onto Campy-Cefex plates or by adding 5 ml to 45 ml of Bolton’s (B) and 45 ml of Tecra (T) broth; after 48h at 42oC both enrichments were streaked onto Campy-Cefex plates. After 4 months at 4oC, 0/10, 7/10 and 3/10 were positive by DS, B and T, respectively, while 0/10, 1/10 and 4/10 were positive by DS, B, and T, respectively, at -23oC. From 4 months to 2 years, all 4oC samples were negative, while 2/10 frozen samples were positive in both B and T after 8 months and 1/10 in B at 12, 16 and 20 months and negative at 24 months. With T, all -23oC samples were negative from 8-24 months. Aliquots tested in B from sample #6 were positive after 8 and 20 months frozen storage but negative at other times, while sample #7 was only positive at 16 months. In this limited study it appears that B was slightly better than T for recovery of Campylobacter stored at low temperatures. While Campylobacter are thought to be fragile, this study demonstrates limited survival after long term frozen storage in rinsate alone. Therefore frozen raw foods that are naturally contaminated with Campylobacter may still pose a potential health hazard even after 1-2 years in a freezer.