ABSTRACT
The objective of thermal processing of food products, which involves heating and cooling, is to produce a shelf-stable product, which is free from pathogenic organisms and will not produce food spoilage. The primary necessity is to destroy microorganisms capable of growing in the product and to prevent further spoilage by suitable packaging. In the conventional canning process, which uses a wide range of packaging materials, including tinplate, aluminum, glass, plastics, and composites, the fi lled and sealed containers are subjected to a heating and cooling regime. Alternatively, continuous fl ow heat exchangers can be used and the product packaged under aseptic conditions. The heating and cooling regime is known as the process and this chapter is concerned with the determination and validation of a process for a specifi c product, packed in a particular container size and heat processed in a given type of pressurized retort. The heating medium may involve steam, steam/air mixtures, or hot water, and the cooling medium is primarily water. The technology of canning is not discussed here but is detailed in numerous texts (see, e.g., Lopez, 1987; Fellows, 1990; Rees and Bettison, 1991; Brennan et al., 1992; Larousse and Brown, 1997; Ramaswamy and Singh, 1997). Current developments in the technology of in-container sterilization are fully discussed by Richardson (2001, 2004).
