Science and Our Food Supply: Investigating Food Safety from Farm to Table

Time/Temperature Relationship  

Traditional pasteurization is achieved by exposing foods to heat for a certain length 

of time. Bacteria are very heat-sensitive, and the higher the temperature, the quicker 

they can be inactivated. Using higher heat takes less time to kill pathogenic bacteria, 

whereas using lower heat takes more time. 

Irradiation 

Irradiation is the process in which ionizing energy is used to kill foodborne pathogens. 

During irradiation, an intense pulse of energy is emitted, either from a gamma  

radiation source like Cobalt 60 or from an electrical source like an electron beam  

accelerator. The energy penetrates the food and destroys any bacteria. 

Irradiation damages the microbe’s DNA. Unless it can repair the damage, the microbe 

will die when it grows and tries to duplicate itself.