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Listeria monocytogenes exhibits increased heat tolerance to lethal heating temperature when pre-exposed to sublethal heat stress. The objective of this study was to investigate the differences in survival of L. monocytogenes EGD (Bug600)(serotype 1/2a) in various disinfectants and essential oils after sublethal heat stress at 48[degrees]C for 60 min. The survival of heat stressed L. monocytogenes cells was lower in lethal acid (HCl or [H.sub.3]P[O.sub.4] pH 2.5), lethal oxidative stress ([H.sub.2][O.sub.2] 1000 ppm) and lethal quaternary ammonium compounds (QAC 2.5-3.5 ppm) than the non-stressed control cells. By contrast, the survival of heat stressed L. monocytogenes cells was higher when exposed to lethal alkali (NaOH or KOH pH 12) than the control. In essential oils, the survival of heat stressed L. monocytogenes cells was higher when exposed to lethal carvacrol (428 ppm) and bay oil (1100 ppm) and the survival was lower in red thyme oil (300 pm) compared to control. On the other hand, there was no change in the survival of heat stressed cells in lethal cinnamon oil (1050 ppm) compared to control. This study indicated that the heat stressed cells of L. monocytogenes are not easily killed by NaOH- or KOH-based alkaline disinfectants, and in essential oils containing carvacrol and bay oil. Therefore, these sanitizers should be carefully considered when sublethal heat stressed cells of L. monocytogenes may be present. Keywords: Listeria monocytogenes, heat stress adaptation, cross protection, disinfectants, essential oils, INTRODUCTION Listeria monocytogenes is a Gram-positive, facultative anaerobic foodborne pathogen associated with a variety of food products such as meat, poultry, fresh produce and dairy products (Farber and Brown, 1990; [...]