ABSTRACT
Thermal processing, the use of heat to reduce the microbial populations in food, inactivates pathogenic and spoilage microorganisms, resulting in an increased shelf life; halts unfavorable enzymatic activity that causes spoilage; and increases the safety of foods. Traditionally, the kinetics of thermal destruction of bacteria was assumed to follow first-order kinetics; that is, the rate of death is expected to be logarithmic. Primary thermal inactivation models describe changes in the microbial cell population as a function of time at a defined set of conditions. Numerous papers discuss the impact of variables, especially temperature, on inactivation of target microorganisms. Increasing fat content has been implicated in increased thermal resistance of pathogens in food. The temperature history of the pathogen prior to thermal treatment can have an impact on thermal inactivation of the pathogen. The level of pathogen inactivation required for any particular food will be dependent on levels of pathogen initially present, as well as the thermal resistance of the pathogen.
