The effect of temperature of incubation on lag times of two gram-negative foodborne bacteria was investigated. Bacteria were instantaneously transferred between temperatures within and beyond the normal physiological temperature range (NPTR). Abrupt temperature shifts induced lag phases, but the degree of the response was dependent on the direction and magnitude of the shift. Temperature downshifts induced larger relative lag times (RLT; the ratio of lag time to generation time), than equivalent upshifts. The hypothesis of Robinson et al. [Int. J. Food Microbiol. 44 (1998) 83] that lag time can be understood in terms of the amount of work to be done to adjust to new environmental conditions and the rate at which that work is done was supported. Deviation of the reported proportionality between lag time and generation time was observed when late-exponential phase cells were subjected to abrupt temperature shifts from beyond the normal physiological range. © 2002 Elsevier Science B.V. All rights reserved.

Item Type:	Refereed Article
Research Division:	Biological Sciences
Research Group:	Microbiology
Research Field:	Microbiology not elsewhere classified
Objective Division:	Health
Objective Group:	Public health (excl. specific population health)
Objective Field:	Food safety
UTAS Author:	Mellefont, LA (Dr Lyndal Mellefont)
UTAS Author:	Ross, T (Professor Tom Ross)
ID Code:	26371
Year Published:	2003
Web of Science® Times Cited:	69
Deposited By:	Agricultural Science
Deposited On:	2003-08-01
Last Modified:	2004-05-11
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