Researchers at the U.S. Department of Agriculture’s Agricultural Research Service (USDA’s ARS) have developed a thermal pasteurization method based on Radio Frequency (RF) technology that effectively reduces the presence of Salmonella in intact eggs, in a fraction of the time required for traditional pasteurization.
Although thermal pasteurization is proven to inactivate pathogens in intact eggs, less than 3 percent of commercial eggs are pasteurized in the U.S., as the process can take more than 57 minutes, according to ARS. Conventional thermal pasteurization involves submerging the eggs fully in hot water.
Similar to traditional pasteurization, the novel technique uses heat to reduce the presence of pathogens. When subjected to RF treatment, the water molecules inside an egg rotate and align with the RF instrument’s electric field, causing molecular friction that rapidly heats up the liquid inside of the egg.
The new RF processing method was shown to reduce the presence of Salmonella in eggs by 99.999 percent within 24 minutes. Additionally, the presence of Salmonella was not detected in the RF-processed eggs after being stored at 7 °C for seven days, simulating commercial cold chain conditions. The quality of the eggs was also not diminished by RF processing.
ARS researchers are continuing to progress work on the new technology’s capabilities and expect it to be commercially available in the near future.