MICROBIAL MODELING AND BIOINFORMATICS FOR FOOD SAFETY AND SECURITY
Location: Residue Chemistry and Predictive Microbiology
Title: Survival of Campylobacter jejuni and Campylobacter coli in retail broiler meat stored at -20, 4 and 12C, and development of predictive models of survival based on temperature and time
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 18, 2010
Publication Date: September 1, 2010
Citation: Speegle, L., Oscar, T.P., Nyati, H., Oyarzabal, O.A. 2010. Survival of Campylobacter jejuni and Campylobacter coli in retail broiler meat stored at -20, 4 and 12C, and development of predictive models of survival based on temperature and time. Journal of Food Protection. 73:1438-1446.
Interpretive Summary: The survival of two Campylobacter jejuni (c. jejuni) and two Campylobacter coli (c. coli)strains isolated from broiler meat was studied in inoculation experiments using boneless, skinless retail broiler breast meat. Results were then used to design predictive models for survival based on temperature and time. Modeling studies indicated that the kinetics of survival was affected by storage temperature and species of Campylobacter, but not by strains. Data collected at -20C fitted into a two-phase reduction model, with an important reduction in the number of cells in the first 24 h and a slow decline afterward. Data collected at 4 and 12C fitted into a one-phase reduction model preceded by a period of no pathogen death. The survival of C. jejuni and C. coli was similar at -20C, but C. coli had higher survival rates than C. jejuni at 4 and 12C (P < 0.05). It appears that Campylobacter spp. survive better in broiler meat than on chicken skin and therefore more studies should be performed with retail broiler meat to provide more accurate survival data for risk assessment purposes.
Retail broiler meat undergoes variable freezing and refrigeration temperatures during storage, transportation, display in retail outlets and in consumers’ refrigerators. Due to the relatively high prevalence of Campylobacter found in retail broilers and the low infective dose required to cause human disease, studying the ability of Campylobacter to survive refrigeration and freezing is directly relevant to designing new strategies to improve food safety and public health. Data and modeling results from this study indicated that survival was affected by storage temperature and species of Campylobacter. Survival of C. jejuni and C. coli was similar at -20C (frozen storage), but at 4C (refrigerated storage) and 12C (temperature abuse), C. coli survived better than C. jejuni. Interestingly, Campylobacter survival was highest at 4C, lowest at 12C and intermediate at -20C, indicating that the greatest reduction in Campylobacter numbers and risk of foodborne illness was achieved by temperature abuse of chicken at 12C for 14 days. However, storage of chicken at 12C to reduce risk of foodborne illness from Campylobacter could increase the risk of foodborne illness from other pathogens, such as Salmonella, that might be present and can grow to dangerous levels on chicken breast meat stored at 12C. Thus, temperature abuse of chicken for reduction or elimination of Campylobacter can not be recommended as a viable approach for improving food safety and protecting public health.