ABSTRACT
One of the most important objectives of food processing is to obtain shelf-stable and nutritious food products that can be stored and handled under normal conditions. To ensure the stable shelf life the foods to be processed have to be commercially sterilized to destroy both pathogenic microorganisms that cause the food to become unsafe for consumption as well as the microorganisms responsible for spoilage. So that they can provide valuable nutrients, foods after processing must continue to remain safe and healthy during storage. Thermal processing, one of most widely used sterilization technologies, is still the dominant technique in food industries. As detailed in Chapter 9, thermal processing can be successfully used to produce safe and shelf-stable foods. Usually, the heat resistance of nutrients and other quality components is much larger than that of microorganisms. This fact is taken advantage of in high temperature short time (HTST) processing techniques and in the optimization of several thermal processing technologies, such as retort pouch processing, agitation processing, and aseptic processing. In recent years, advanced processing techniques such as microwave heating and ohmic heating, as well as related computer control
technologies, have made it possible for food industries to produce foods with optimal qualities using the idea of deliverable rapid temperature profiles. However, it is a fact that all thermal processing techniques, however advanced, cannot fully eliminate nutrient degradation. Hence, several advanced nonthermal processing technologies such as high-pressure processing and electrical pulse processing have received attention in recent years as alternatives to conventional thermal processing for producing higher quality products. In this chapter, the concepts involved in some novel processing techniques are introduced.
