EFFECT OF RISING TEMPERATURE ON THE HEAT-RESISTANCE OF LISTERIA-MONOCYTOGENES IN MEAT EMULSION

The heat resistance of a strain of L. monocytogenes was determined both in broth and in meat emulsion. The D-values for meat emulsion were approximately two to three times higher than those for broth and also the z-value increased significantly. The micro-organism proved to be more resistant when the cells were heated up slowly (0.5-degrees-C/min) to constant temperatures of 60, 63 and 66-degrees-C in meat emulsion. The D60, D63 and D66 were, respectively 12.95, 5.4 and 2.3 min. Results may have implications in the survival of Listeria monocytogenes in particular food preparations.