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This research project aims to investigate the ways butter and butter-containing spreads are formulated, manufactured and handled and to determine how these factors affect the growth and survival of different strains of L. monocytogenes, particularly outbreak strains.
<p>This project will look at the ways in which butter and butter-containing spreads are formulated, manufactured and handled. It will link the characteristics of L. monocytogenes, especially outbreak strains, to the attributes of the butters.
<p>Following practical work in butter production, the project will derive conclusions about the safety of butter and butter-containing spreads with respect to L. monocytogenes.
Butter has recently been implicated in a small but significant number of listeriosis outbreaks, including an outbreak that occurred in England in 2003.
<p>This has raised a number of questions about the growth and survival of L. monocytogenes in relation to the formulation and structure of butter and how subsequent storage and handling practices influence the behaviour of this organism.
<p>Butter is a water-in-fat emulsion comprising water droplets of varying size and number, depending on the formulation and manufacturing conditions.
<p>While some studies have shown little or no growth of L. monocytogenes in butter, other studies have reported growth at both refrigeration and ambient temperatures.<P>
The final report, "<a href="http://www.foodbase.org.uk/results.php?f_report_id=335" target="_new">To Investigate the Impact of Butter Production on Growth of Listeria Monocytogenes</A>" is available at Foodbase, an open access repository of the <acronym title="Food Standards Agency"> FSA</acronym>.
<p>Find more about this project and other FSA food safety-related projects at the <a href="http://www.food.gov.uk/science/research/" target="_blank">Food Standards Agency Research webpage</a>.