ARS | Publication request: Effect of Dry Air and Immersion Chilling on Bacteria Recovery from Broiler Carcasses

Submitted to: Southern Poultry Science Society Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 13, 2006
Publication Date: January 26, 2007
Citation: Huezo, R., Northcutt, J.K., Smith, D.P., Fletcher, D.L., Ingram, K.D. 2007. Effect of Dry Air and Immersion Chilling on Bacteria Recovery from Broiler Carcasses [abstract]. Southern Poultry Science Society Meeting Abstracts. Poultry Science. 86(Suppl.1):737.

Technical Abstract: A study was conducted to investigate the effect of chilling method (air and immersion) on Escherichia coli, coliforms, Campylobacter, and Salmonellae counts and prevalence recovered from broiler carcasses. During each of four replications, 60 broilers were inoculated orally and intra-cloacally with 1 mL of a suspension containing approximately 108 cells/mL of Campylobacter. After one day, broilers were inoculated with 1 mL of a suspension containing approximately 108 cells/mL of Salmonella. Broilers were processed and carcasses were cooled by dry air (3.5 m/s, -1.1o C, 150 min) or immersion chilling in ice water (0.6o C, 50 min). Pre-chill counts recovered from carcasses averaged 3.5, 3.7, 3.4, and 1.4 log10 cfu/mL of rinse for E. coli, coliforms, Campylobacter, and Salmonella, respectively. Overall, both chilling methods significantly reduced bacteria levels on the carcasses, and no difference in the bacteria counts was observed between the two chilling methods (P < 0.05). Both chilling methods reduced E. coli and coliforms levels by 0.9 to 1.0 log units. Chilling reduced Campylobacter levels by 1.4 log (air) and 1.0 log (immersion), while Salmonella reductions were 1.0 log and 0.6 log units for air and immersion chilling, respectively. Chilling method had no effect on the prevalence of Campylobacter and Salmonella recovered form carcasses. These results demonstrate that air and immersion chilled carcasses, without any chemical intervention, are microbiologically comparable, and a 90% reduction in counts of E. coli, coliforms, and Campylobacter can be obtained after chilling.