ARS | Publication request: An enumeration method and sampling plan for mapping the number and distribution of Salmonella on the chicken carcass

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 29, 2007
Publication Date: July 8, 2007
Citation: Oscar, T.P. 2007. An enumeration method and sampling plan for mapping the number and distribution of Salmonella on the chicken carcass. Meeting Abstract. IAFP. P2-69.

Technical Abstract: Knowledge of the number and distribution of pathogens on foods will improve food safety by allowing better assessment and management of this important risk to human health. However, knowledge of food pathogen ecology and its response to food production and processing practices is limited. Consequently, a selective plating media with multiple antibiotics (XLH-CATS) and a multiple drug resistant (MDR) strain of Salmonella Typhimurium DT104 were used to develop an enumeration method and sampling plan for mapping the number and distribution of Salmonella on young chickens in the Cornish game hen class. The enumeration method was based on the concept that the time to detection on XLH-CATS during incubation of chicken parts in buffered peptone water (BPW) is inversely related to the initial log10 number (ID) of Salmonella. The sampling plan for mapping involved dividing the chicken into 12 parts that ranged in average size from 42 to 80-g. To develop the enumeration method, the parts were spot inoculated with 0 to 6 log10 CFU of the MDR strain of DT104 followed by incubation in 300 ml of BPW and detection on XLH-CATS. An inverse relationship between detection time (DT) on XLH-CATS and log10 ID was found: DT (h) = 7.72 – (0.973*No); R2 = 0.968. Type and size of chicken part and brand of chicken did not alter (P > 0.05) the linear relationship between DT and ID. Because DT was variable within ID among chickens (n = 12), the final linear equation for enumeration included a 95% prediction interval that provided stochastic results for ID. The enumeration method and sampling plan will be used in future studies to map changes in the number and distribution of Salmonella on young chickens fed the MDR strain and subjected to different production and processing practices.