ABSTRACT
Thermal processing of canned foods has been one of the most widely used methods of food preservation during the 20th century and has contributed significantly to the nutritional well-being of much of the world’s population. Thermal processing consists of heating food containers in pressurized retorts at specified temperatures for prescribed lengths of time. These process times are calculated
on the basis of achieving sufficient bacterial inactivation in each container to comply with public health standards and to ensure that the probability of spoilage will be less than some minimum. Associated with each thermal process is always some undesirable degradation of heat-sensitive vitamins and other quality factors. Because of these quality and safety factors, great care is taken in the calculation of these process times and in the control of time and temperature during processing to avoid either under-or overprocessing. The heat transfer considerations that govern the temperature profiles achieved within the container of food are critical factors in the determination of time and temperature requirements for sterilization. This chapter will focus on the development and application of deterministc heat transfer models capable of accurately predicting internal product temperature in response to retort operating conditions, and coupling these with deterministic models that mathematically describe the thermal inactivation kinetics of bacterial spores and food quality factors for thermal process simulation.
