Combined Water Activity and Solute Effects on Growth and Survival of Listeria monocytogenes Scott A

A J Miller

doi:10.4315/0362-028X-55.6.414

Combined Water Activity and Solute Effects on Growth and Survival of Listeria monocytogenes Scott A

J Food Prot. 1992 Jun;55(6):414-418. doi: 10.4315/0362-028X-55.6.414.

Author

A J Miller¹

Affiliation

¹ Eastern Regional Research Center, Agricultural Research Service U. S. Department of Agriculture, 600 E. Mermaid Lane, Philadelphia, Pennsylvaina 19118.

PMID: 31071853
DOI: 10.4315/0362-028X-55.6.414

Abstract

Water activity and solute effects were determined on the growth and survival of Listeria monocytogenes Scott A in bacteriological media. Media were adjusted to water activity (a_w) levels of 0.99-0.80 with NaCl, glycerol (GLY), or propylene glycol (PG). Minimum a_w levels for growth occurred at 0.90, 0.92, and 0.97 for GLY, NaCl, and PG, respectively. Survival was related to the a_w level, as well as the solute employed. Cells survived the longest in GLY and died earliest in PG; NaCl was intermediate. These results provide quantitative isothermal criteria for estimating the a_w level necessary to prevent growth of L. monocytogenes in food.