Each of the 10 carcasses were rinsed and tested for Campylobacter. Each rinse was subdivided into twelve 25-mL aliquots, without cryoprotectant. Six were stored at 4C and six at −23C. At 4-month intervals, one aliquot from each was streaked onto Campy-Cefex plates and then 5 mL added to 45 mL of Bolton's (B) or 45 mL of Tecra (T) broth; after 48 h at 42C, both enrichments were streaked onto Campy-Cefex plates. At 4 months (4C), 0 of 10, seven of 10 and three of 10 were positive by direct streak, B and T, respectively, while 0 of 10, one of 10 and four of 10 were positive by direct streak, B and T, respectively, at −23C. At 4 months, all 4C samples were negative, while two of 10 frozen samples were positive in both B and T after 8 months and one of 10 in B at 12, 16 and 20 months. Foods contaminated with Campylobacter may still pose a health hazard after long-term freezing.
In this study, naturally occurring Campylobacter were able to survive in the rinsate of commercially processed broiler carcasses without the use of a cryoprotectant. The Campylobacter isolate was identified as a nalidixic acid and ciprofloxacin resistant strain of Campylobacter jejuni. Survival and periodic recovery were demonstrated after 20 months of frozen storage in broiler carcass rinsate alone. Therefore, naturally contaminated uncooked frozen poultry may pose a potential health hazard.