Thermal Inactivation of Microorganisms

Abstract This paper serves as an overview of various aspects of thermal processing. Heat processing of foods has a long history and is still one of the most important preservation methods. To guarantee microbiological safety and stability, large safety margins are often applied in traditional heat processes. Because of the need for more fresh like foods, there is a need for milder preservation methods without compromising on safety and stability. The review deals with heat resistance data and mathematical models that describe heat inactivation. The effects of food composition are not yet fully clear and more knowledge of the cell physiology of the target microorganism could be of help in predicting the effects of food constituents. Finally, special attention has been paid to biological time temperature indicators to enable proper process calculations. Keywords: Bacterial spores D and z valuetime temperature integratorheat stresssublethalnonlinear ACKNOWLEDGMENTS The authors would like to thank Tom McMeekin, June Olley, Marcel Zwietering, and the anonymous reviewer for critically reading the manuscript and for helpful suggestions.