It's easy to think of soap suds when one thinks of bubbles, but these bubbles can clean without chemicals. These are cavitation bubbles, which are created when air is churned up in water. And what researchers are learning could ultimately lead to chemical-free cleaning methods for fruits and vegetables.
With support from the National Science Foundation (NSF), biofluid scientist Sunghwan "Sunny" Jung and his team at Virginia Tech are studying how a cavitation bubble creates a suctioning effect when it collapses, pulling everything close by toward it. Cavitation bubbles are already in use for certain industrial applications, such as cleaning water at treatment plants. Jung's fluid mechanics lab is working with food scientists to see how effective cavitation bubbles are at pulling everything from soil to E. coli and Salmonella away from the smooth surface of a tomato or the bumpy surface of a cantaloupe. In the future, Jung envisions bubble machines as a common appliance at farmer's markets and maybe even in households. 11 Jan 2016