Project Number: 1935-41420-013-01
Project Type: Specific Cooperative Agreement

Start Date: Sep 15, 2007
End Date: Jun 30, 2009

Objective:
Compare mechanisms of inactivation of Salmonella Typhimurium by three nonthermal processing technologies, pulsed electric field (PEF), pulsed ultraviolet radiation (PUV) and super-critical carbon dioxide (ScCO2).

Approach:
This collaborative research is scheduled for 12 months. A post-doctoral researcher will be hired by Ohio State University and trained to conduct mechanistic studies using very specific gene chips developed and contributed by OSU. The training of the post-doc and initial studies will be conducted at OSU. The post-doc will conduct a 3-months study at ERRC with pilot plant processing equipment for PEF, PUV and ScCO2 technologies. As part of the collaboration, OSU will transfer a pilot plant PEF system to ERRC ($640k value when new) to be integrated with the aseptic processing and packaging line where products may be processed and packaged for safety, quality and shelf life studies. Spotted-array gene chips will be used to assess changes in gene expression in response to applied treatments. Salmonella Typhimurium will be treated with sublethal doses of PEF, PUV and ScCO2. RNA of treated cells will be extracted, and cDNA is prepared, labeled, and applied to the gene chips. After hybridization, the chips are scanned in a microarray scanner, and results are statistically analyzed. Results of the analysis will reveal the alternations in gene transcription in response to these treatments. These preliminary gene expression data will allow us to propose pathways these cells use to overcome treatment lethality.