Enumeration of Salmonella enterica in meat samples with Droplet Digital PCR
This project will demonstrate the sensitivity and specificity of droplet digital PCR as an enumeration assay for Salmonella enterica in pure culture and in mixed microflora cultures as well as inoculated ground beef of different fat contents
Several different serovars of Salmonella enterica, corresponding to those commonly found in meat products based on the USDA-FSIS quarterly reports on Salmonella serotyping, will be enumerated at different populations using digital droplet PCR, and compared to conventional surface plate enumeration methods. The experiments will be repeated using a mixed microflora, using purge from vacuum-packaged beef as a source of the non-pathogenic bacteria.
Ground beef with different fat contents will be inoculated with individual strains of Salmonella. The target populations of Salmonella will range from 2 cells/10 grams to 1000 cells per gram. The samples will be enumerated by both DDPCR and standard methods, and a comparison will be made between the two methods to establish the sensitivity of the DDPCR method.