Journal
FOOD MICROBIOLOGY
Volume 36, Issue 2, Pages 355-364Publisher
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1016/j.fm.2013.06.015
Keywords
Sublethal injury; Mild heating; Cell colony; Food model systems; Xanthan gum; Escherichia coli; Salmonella Typhimurium; Listeria innocua
Funding
- KU Leuven Research Council [PFV/10/002]
- KU Leuven Industrial Research Fund [KP/09/005]
- Belgian Program on Interuniversity Poles of Attraction by the Belgian Federal Science Policy Office
- Belgian chemistry and life sciences federation essenscia
Ask authors/readers for more resources
The occurrence of sublethally injured cells in foods poses major public health concerns and is an essential aspect when assessing the microbial response to food preservation strategies, yet there is limited research dealing with its specific implications for mild heating. All available studies so far have been performed in broths colonized by planktonic cells, although their susceptibility to lethal agents has often been reported to be markedly different to the stress tolerance of cell colonies developed in solid foods. In this work, the effect of planktonic and colony growth, as well as the influence of colony density on sublethal injury induced by mild heating of Escherichia coli, Salmonella Typhimurium and Listeria innocua were assessed in food model systems. Detection of injured survivors relied on their inability to form visible colonies on salt-based selective media, which do not affect the growth of healthy cells. Sublethal injury (SI) increased rapidly with shorter exposure times and afterwards, decreased progressively, suggesting a mechanism of cumulative damage triggering lethal instead of SI. Cell arrangement affected the degree of SI, higher values being generally found for gelified systems, although the effect of colony density depended on the target microorganism. This information is essential for optimizing the design of food safety assurance systems. (C) 2013 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available