<P>This research project aims to clarify the mechanism(s) that aid survival of Mycobacterium paratuberculosis (MAP) during heating and to identify the times and temperatures required to inactivate MAP if present in milk. </p>
The aims of the project were:
<li>To determine the mechanism(s) that enables MAP to survive pasteurisation by investigating a number of factors which may influence thermal inactivation characteristics. The factors to be investigated include the effect of suspending menstruum (whole milk v skim milk v UHT milk), source of inoculum (solid v liquid medium), declumping, macrophage engulfment, heat shock response, freezing and thawing, stage of growth and rate of heating.</li>
<li>To identify a processing regime that will achieve the complete inactivation of high numbers of MAP in milk.
To optimise decontamination protocols for the isolation of MAP and Mycobacterium bovis from milk. </li>
<li>To modify the immunomagnetic PCR assay for application to different types of cheese.</li>
Previous MAFF-funded research has found that Mycobacterium avium subsp. paratuberculosis (MAP) was able to survive laboratory heat treatments simulating commercial milk pasteurisation conditions (72°C for 15 seconds). This project was commissioned to clarify the mechanism(s) that aid survival of this organism and also identify what combination of holding times and temperatures would be necessary to ensure the complete inactivation of MAP if present in milk in high numbers.
<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>.