Survival of a desiccated five-strain Listeria monocytogenes mixture during storage in sand at 4 degrees C for 2 months was determined using the acridine orange direct count method with novobiocin and plate counts. Samples of inoculated sand were taken every 2 weeks, incubated at 37 degrees C for 6 h, stained with acridine orange, and then examined with a fluorescence microscope. Elongated viable but nonculturable cells were most frequently observed during weeks 2 and 4.
View Article and Find Full Text PDFFive individual strains of Listeria monocytogenes and a mixed cocktail of all five were studied for attachment on frankfurters, ham, bologna, and roast beef relative to their cell surface characteristics. The ratio of strongly attached (sessile) L. monocytogenes cells compared with total (sessile and planktonic) attached cells on ready-to-eat meats was also determined.
View Article and Find Full Text PDFA five-strain Listeria monocytogenes culture was inoculated onto six different types of ready-to-eat (RTE) meats (frankfurters, ham, roast beef, bologna, smoked turkey with lactate, and smoked turkey without lactate). The meats were vacuum packed and stored at 4 degrees C for 24 h prior to irradiation. Populations of L.
View Article and Find Full Text PDFDust from construction was theorized to serve as a vector for L. monocytogenes transmission to ready-to-eat (RTE) meats after heat processing but before packaging. A five-strain Listeria monocytogenes culture including serotype 4b was continually stressed on a sand vector under four sets of nutritionally depleted and dry conditions to simulate postprocessing contamination by dustlike particulates.
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