1. Microbiology & Food Hygiene

A study of the factors controlling the survival, germination and outgrowth of Bacillus cereus in rice–based model foods using novel rapid flow cytometry methods and biochemical markers

Project Reference:

03–PG–011

Status:

Completed

Commencement Date:

October, 2003

Project Duration:

36 months

Abstract:

The consumption of takeaway meals and cooked chilled foods containing rice is popular nowadays. The main pathogen associated with cooked rice is Bacillus cereus, which can cause emetic or diarrhoeal food poisoning. It poses a food safety hazard because of its ability to exist as dormant spores and sub–lethally injure vegetative cells after cooking.

In this project, a rapid, precise, accurate, repeatable and sensitive flow cytometric method for detecting Bacillus cereus was developed capable of rapidly identifying and enumerating viable and spore–forming cells. The method was used to assess the impact of various processing, storage and cooking regimes on the survival and reactivation of Bacillus cereus in rice–based foods.

Principal Contractor(s):

Dr Martin Wilkinson, University of Limerick

Collaborator(s):

Single supplier

Outputs:

Report:

The PhD thesis is available on request and can be accessed through the University of Limerick

Peer review:

Cronin, U.P. and Wilkinson, M.G., The use of flow cytometry to study the germination of Bacillus cereus endospores. Cytometry A., Mar, 71(3): 143-53, 2007.

Cronin, U.P. and Wilkinson, M.G., Bacillus cereus endospores exhibit a heterogeneous response to heat treatment and low-temperature storage. Food Microbiology, 25: 235–243, 2008.

Cronin, U.P. and Wilkinson, M.G., Monitoring growth phase-related changes in phosphatidylcholine-specific phospholipase C production, adhesion properties and physiology of Bacillus cereus vegetative cells. J Ind Microbiol Biotechnol., 5: 1695–1703, 2008.

Cronin, U.P. and Wilkinson, M.G., Physiological response of Bacillus cereus vegetative cells to simulated food processing treatments. J Food Prot., Nov 71(11): 2168-76, 2008.