This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Goepfert, J. M. Articles by Amundson, C. H. Search for Related Content PubMed Articles by Goepfert, J. M. Articles by Amundson, C. H. Agricola Articles by Goepfert, J. M. Articles by Amundson, C. H.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1970 March; 19(3): 429-433
Copyright © 1970 American Society for Microbiology. All Rights Reserved.

Relation of the Heat Resistance of Salmonellae to the Water Activity of the Environment ¹

Food Research Institute, Department of Bacteriology, and Department of Food Science, University of Wisconsin, Madison, Wisconsin 53706

ABSTRACT

The effect of water activity (a_w) on the heat resistance of eight strains of Salmonella was studied. Heat resistance of the organisms increased as the a_w of the heating menstruum was reduced. Sucrose afforded the cells a greater degree of protection than did fructose, glycerol, and sorbitol. A direct correlation between a_w and heat resistance could not be established over the range of a_w levels tested in this study. There was variation among the strains of salmonellae in the magnitude of the increase in heat resistance as the a_w level was reduced. All strains of Salmonella tested showed a greater increase in heat resistance than S. senftenberg 775W as the environment became drier. Washed cells had D values 25 to 75% lower than unwashed cells. Prior growth of the organisms in media with a reduced a_w increased the heat resistance of the organisms when glycerol, but not when sucrose, was the controlling substance.

¹ Published with the approval of the Director of the Research Division, College of Agricultural and Life Sciences, University of Wisconsin.