Numerous examples of non-linear survival curves, plotted as log surviving cells vs. time, for bacteria exposed to heat have been reported. Factors which may affect the shape of a survival curve and the heat resistance of bacteria include temperature, pH, and NaCl concentration. Many studies have examined the effect of these factors individually, but little information exists on the combined effects. The objective of this study was to mathematically model non-linear survival curves to account for these factors and their interactions simultaneously.
Heat resistance of <u>Listeria monocytogenes</u>(L. <u>monocytogenes</u>) was determined in O.lM KH₂P0₄ buffer and in infant formula at three temperatures (50, 55, and 60 C), three pH levels (5, 6, and 7), and three NaCl concentrations (0, 2, 4%). Survival curves were fit using linear regression, non-linear regression with a modified logistic equation, and non-linear regression with a modified Gompertz equation. / Ph. D.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/27971 |
| Date | 06 June 2008 |
| Creators | Linton, Richard Howard |
| Contributors | Food Science and Technology, Pierson, Merle D., Hackney, Cameron Raj, Johnson, Janet M., Marcy, Joseph E. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Dissertation, Text |
| Format | xiii, 189 leaves, BTD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 31183715, LD5655.V856_1994.L568.pdf |
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