TY - JOUR TI - Understanding and managing the risk from Salmonella on cucumbers DO - https://doi.org/doi:10.7282/T3PV6PT7 PY - 2018 AB - Recent multistate outbreaks of salmonellosis directly associated with fresh cucumbers highlight the importance of understanding the factors that may influence or contribute to the risk of Salmonella contamination on cucumbers. The studies in this dissertation increase our limited knowledge of select factors on Salmonella behavior in cucumbers. The results in Chapter 2 show that significant bacterial transfer from cucumber skin to edible flesh portion and peeler occurred during peeling no matter what microorganisms exist on the surface of cucumber. There was no significant difference between transfer of S. Newport and E. aerogenes, indicating that E. aerogenes B199A could be used as surrogate for S. Newport in cross-contamination studies regarding cucumbers. The main finding from Chapter 3 was that curli and cellulose-producing S. Newport wild type showed better attachment to the surface of cucumber compared to non-producing mutant strains, but curli and cellulose did not have a significant influence on transfer of S. Newport to edible flesh portion of cucumber during peeling. These suggest that bacterial cell surface components including curli, cellulose, flagella, and capsular polysaccharides are all involved in complex interaction of S. Newport with cucumber, but that other, more important mechanisms influence Salmonella attachment and transfer to cucumbers. Chapter 4 shows that Salmonella are able to survive on the surface of cucumbers stored at 7 and 21 °C for up to 7 days, whether the cucumber was waxed or un-waxed. Significant transfer of Salmonella from inoculated cucumbers to brushes and un-inoculated cucumbers was found during cucumber waxing. Salmonella remaining on the contaminated cucumbers after waxing survived up to 7 days, and Salmonella showed better survival on the cucumbers treated with a petroleum-based wax. These results suggest that survival and transfer of Salmonella vary depending on the type of wax coatings. The models developed in Chapter 5 predict the growth and survival of Salmonella on whole and cut cucumbers as a function of temperature and RH. These findings should be useful for future microbial risk assessments and predictions of Salmonella behavior in cucumbers to manage the risk of Salmonella with respect to cucumbers. KW - Food Science KW - Salmonella infections--Prevention KW - Salmonella food poisoning KW - Cucumbers LA - eng ER -