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ARS Home » Northeast Area » Wyndmoor, Pennsylvania » Eastern Regional Research Center » Microbial and Chemical Food Safety » Research » Publications at this Location » Publication #281472

Title: Initial contamination of chicken parts with Salmonella at retail and cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation

Author
item Oscar, Thomas

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/17/2012
Publication Date: 1/13/2013
Citation: Oscar, T.P. 2013. Initial contamination of chicken parts with Salmonella at retail and cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation. Journal of Food Protection. 76:(1)33-39.

Interpretive Summary: Although the poultry industry and regulatory agencies are doing their best to reduce or eliminate Salmonella from poultry farms and processing plants, ready-to-cook chickens sold at retail continue to be contaminated with Salmonella. Therefore, a study was undertaken to determine the levels of Salmonella on edible parts prepared from chickens purchased at retail and to determine how many Salmonella are transferred to other foods during meal preparation. Data for cross-contamination were obtained by cutting up a sterile, cooked chicken breast with the same board and knife used to cut-up the raw chicken. Prevalence of initial contamination of chicken parts was 3%, whereas incidence of cross-contamination of cooked chicken with Salmonella from raw chicken was 1.8%. The positive chicken parts were thigh from chicken #4, which contained 3 cells of Salmonella, and both wings, one thigh and one cooked breast portion from chicken #15, which all contained 1 cell of Salmonella. These results indicated that the poultry industry is providing consumers in the studied geographical area with chicken that has a low prevalence and low number of Salmonella at retail and that even under a worse-case food handling scenario has a low potential for cross-contamination of other foods with Salmonella from raw chicken during meal preparation.

Technical Abstract: The current study was undertaken to acquire data for initial contamination of chicken parts with Salmonella at retail and to acquire data for cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation. Whole raw chickens were obtained from local retail stores and cut into two wings, two breasts without skin or bones, two thighs and two drumsticks. Data for cross-contamination were obtained by cutting up a sterile, cooked chicken breast with the same board and knife used to cut-up the raw chicken. The board, knife and latex gloves used by the food handler were not rinsed or washed before cutting up the sterile, cooked chicken breast; thus, providing a worst-case scenario for cross-contamination. Standard curves for the concentration of Salmonella in 400 ml of buffered peptone water after 6 h of incubation of chicken parts as a function of the initial number of Salmonella inoculated onto chicken parts were developed and used to enumerate Salmonella. Standard curves were not affected by type of chicken part but did differ (P is less than 0.05) among the five isolates of Salmonella examined. Consequently, Salmonella were enumerated on naturally-contaminated chicken parts using a standard curve developed with the serotype of Salmonella that was isolated from the original sample. Incidence of initial contamination was 3% (4/132), whereas incidence of cross-contamination was 1.8% (1/57). The positive chicken parts were thigh from chicken #4, which contained 3 CFU of serotype Kentucky, and both wings, one thigh and one cooked breast portion from chicken #15, which all contained 1 CFU of serotype 8,20:-:z6. These results indicated that the poultry industry is providing consumers in the studied area with chicken that has a low prevalence and low number of Salmonella at retail and that has a low potential for cross-contamination of cooked chicken with Salmonella from raw chicken during meal preparation under a worst-case scenario.