Emerging Technology for Mitigating Burden of Foodborne Bacteria of Public Health Concern
Diseases caused by foodborne pathogens are serious public health challenge affecting many lives and creating challenges to the health of the individuals. People who are elderly, small children, the pregnant women, and the immunocompromised people are at greatest risk. It is creating problems both globally and nationally. The first chapter of this dissertation is focused on the studies related with the sensitivity of Staphylococcus aureus to elevated levels of hydrostatic pressure in the presence of antimicrobials such as nisin, carvacrol and caprylic acid. At high pressures, nisin had mild effects to enhance the decontamination efficacy of the pathogen. Mild heat enhanced the decontamination effect of this pathogen and also the antimicrobials were effective to reduce the pressure treatment time. The second chapter is about the studies related with the inactivation of pressure-stressed and wild-type Cronobacter sakazakii using pressure-based pasteurization. The application seems to be effective to enhance the pressure-based decontamination of Cronobacter sakazakii. The application of protamine and defensin were additionally effective to reduce the bacterial counts. The third chapter is focused on the studies related with the biofilm formation of pathogenic Listeria monocytogenes and Salmonella serovars and non-pathogenic Listeria innocua and Salmonella LT2 and their inactivation on stainless steel coupons. All treatments tested were found to be effective for eliminating the planktonic cells of pathogenic and non-pathogenic cells of Listeria spp. and Salmonella serovars. Overall, 5% acetic acid seems to be less effective compared to sodium hypochlorite and quaternary ammonium compounds. The last chapter is focused on the studies related with the decontamination of four bacterial spores using thermal assisted high-pressure processing. Bacterial spores usually show more resistance to harsh conditions unlike the vegetative cells of the bacteria. Modest reduction in the spore counts happened due to high-pressure treatments. The use of nisin at a very high concentration reduced the spore counts of the bacterium Bacillus amyloliquefaciens. When bacteriocin is combined with high-pressure processing, this could effectively reduce the bacterial spore counts by up to 99%.
Agriculture|Environmental Studies|Food Science
"Emerging Technology for Mitigating Burden of Foodborne Bacteria of Public Health Concern"
ETD Collection for Tennessee State University.