Ultrasound cleaning of salad could reduce instances of food poisoning A study published in the magazine Ultrasound in Medicine and Biology reveals that cleaning salad with an ultrasound system would be the best way to reduce the microbial load in fresh salads. Since salad is rarely cooked, it is essential to wash it before eating it. Water cannot however remove all harmful bacteria, and the use of cleaning products, bleach or other disinfectants is not recommended. Professor Timothy Leighton from the University of Southampton has invented a technology to clean salad with ultrasound. He uses gentle streams of water carrying sound and microscopic air bubbles in order to remove bacteria from salad leaves.