Pulsed Ultraviolet Light And Radio Frequency Treatments

Pulsed Ultraviolet Light And Radio Frequency Treatments

The Chemistry & Agriculture Program at the Crocker Nuclear Laboratory, in collaboration with several departments at UC Davis, is investigating the applications of pulsed ultraviolet light (PUV) and of selected radio frequency bands (RF) to affect the reproduction mechanisms of pathogenic organisms in several media, including fresh (fruits & vegetables), processed foods, waste materials, and many other non food materials such as soils and wood. PUV has been shown to affect microbial flora on the surface of fresh fruits and control pathogenic bacteria (> 7 log reduction) and viruses (>7 log reduction) in several transparent or partially transparent liquid fluids such as drinking water, fruit juices, milk, and plasma (US patent # 5,364,645, other patents pending). In addition, PUV is effective for surface insect & mites disinfestation applications (US Patent # 5,607,711). The commercial use of PUV is being investigated for several processes.

RF techniques have been shown to be effective for disinfection and disinfestation applications on similar materials as PUV. However, contrary to the surface effects of PUV or its limitations in depth of penetration in liquid fluids, RF interacts homogeneously in the bulk of a material. Therefore, in addition to fresh fruits, disinfection, disinfestation, and desirable biological effects in several agricultural commodities, in waste materials, animal and human diet products, soils, and wood products, have been shown in a laboratory scale. Several commercial applications are being evaluated.

Manuel C. Lagunas-Solar, Crocker Nuclear Laboratory, UC Davis