48-1

I. A. TAUB, U.S. Army Natick Soldier Center, Natick, MA 01760-5018

The use of irradiation to enhance food safety and to extend shelf life can be optimized by understanding the basic physical, chemical, and biological principles associated with this nonthermal preservation technology. The physical principles determine the nature and extent of energy deposition by the penetrating radiation. The consequent chemical reactions determine the type and amount of chemical change that can occur, depending on the composition of the food and the irradiation conditions. The associated physical and chemical effects on microbial and other biological contaminants determine the effectiveness with which radiation eliminates pathogens and pests.

Because the energy can be uniformly deposited and because the chemical changes are comparatively minor and common to foods of similar composition, irradiation neither compromises nutrition nor introduces any toxicological hazards. Because the changes that do occur might be discerned in such quality attributes as color, flavor, and texture, the foods to be irradiated and the irradiation conditions to be used need to be judiciously chosen to optimize the processing and to produce a safe and highly acceptable pasteurized or sterilized food product.

These principles and their exploitation to optimize irradiated foods are discussed and illustrated.