Toothbrushes have been using sonic power to clean teeth for years. Now, researchers at the University of Illinois at Urbana-Champaign have found that adding ultrasound pulses to the washing cycle used to sanitize spinach can reduce bacteria count, especially when coupled with the traditional chlorine solution rinse.
Reserachers Bin Zhou, Hao Feng and Arne Pearlstein created and tested a spinach-washer with three pairs of ultrasonic heads operating at 25, 40, and 75 kilohertz and found that its use resulted in “significantly lower microbial count reduction” than the chlorine bath alone.
Spinach and other leafy greens that grow close to the soil can harbor dangerous bacteria such as E.coli which can cause serious sometimes llife-threatening illness. So finding a better way to wash greens could lead to a reduction in foodborne illness.
Last month, an E.coli outbreak linked to spinach and spring mix salad greens sold at Wegmans and other grocery stores became the third multi-state E.coli outbreak linked to salad greens in the last three years, according to information from the Centers for Disease Control and Prevention (CDC). The outbreak has sickened 28 people in New York, Connecticut, Virginia, Massachusetts and Pennsylvania. Of those 10 have been hospitalized, two with hemolytic uremic syndrome (HUS), a serious complication that develops from some E.coli infections that leads to kidney failure.
In 2011, an E. coli outbreak linked to romaine lettuce sickend 60 people in 10 states. About 67 percent of those case patients were hospitalized, and 2 people developed HUS. And, in 2010, 28 people in five states were sickened in an E.coli outbreak linked to shredded romaine lettuce.