ABSTRACT
The application of microwave energy to heat foods was patented in 1945 by Percy Spencer of Raytheon Corporation as an offshoot of radar technology developed during World War II. Microwave energy is more efficient and rapid than conventional heating, allowing food to be heated in as little as one quarter of the normal time. There are additional commercial applications of microwave heating other than cooking and reheating operations typically in use by consumers. The intensity of a microwave radiation field is expressed in watts or kilowatts, which are transmitted through a unit cross section of space. Milk has frequently been implicated in the transmission of foodborne pathogens, especially psychrotrophic organisms. Microwave energy from the magnetron flows down the waveguide, a hollow metallic tube, into the oven. Production of heat occurs primarily through dipolar rotation and ionic polarization. Heat transfer by microwaves is markedly different from conventional heating using an electric or gas oven.
