A.MFS.0251 Effects of chilling on the survival of Escherichia coli on carcasses | 2011
| Project start date: | 25 March 2011 |
| Project end date: | 31 August 2011 |
| Publication date: | 31 August 2011 |
| Project status: | Completed |
| Livestock species: | Sheep, Goat, Lamb, Grassfed cattle, Grainfed cattle |
Summary
The review panel was appointed to review and extract additional information from the data obtained by the Australian Food Safety Centre on the transcriptomic and proteomic analysis of the response of pathogenic E. coli to the stresses encountered during chilling of meat carcasses, to suggest possible vulnerabilities and risk mitigation strategies for pathogenic E. coli and make recommendations for further studies.The panel met with the researchers from the Centre and representatives of MLA on two occasions, and provided feedback on the initial meeting and after the provision of the transcriptomics and proteomics data to assist where possible with the analysis.
The panel members are of the view that these analyses have been performed very well and they have both generated many potential new research leads for further investigation.It is clear that the original concept that E. coli cells entered a non-viable state when subjected to lowering of temperature and water activity as a possible way to reduce the burden of the organism during carcass chilling is not a solution to the problem since the organism undergoes recovery and some growth during the later stages of the chilling. Most of the effect of chilling is due to the lowering of water activity on surfaces exposed to chilled airflow.
The data obtained by the researchers do, however, indicate that during exposure to the chilling processes the organism may become more sensitive to other stresses such as to oxidants such as hypochlorite or to DNA damage induced by, for example, UV. This potential vulnerability of the E. coli might therefore provide a suitable way for the industry to use an adjunct treatment to reduce the microbial load. The panel therefore recommends that further research on the non-culturable state of E. coli during the early stages of chilling, the physiology of the changes occurring to E. coli cells during chilling, and the sensitivity of the cells to other stresses could provide a possible way to reduce the load of E. coli on meat surfaces.
