Food poisoning affects one in six Americans every year caused by rotting meat and vegetables , dirty water and unhygienic kitchens . But a new technique using just electricity and water could one day make food safer , without damaging the environment . Researchers claim that tiny nano-sized droplets of electrically charged water filled with free radicals could be sprayed onto food to kill pathogens lurking on the surface . Researchers claim that tiny nano-sized droplets of electrically charged water filled with free radicals , could be sprayed onto fruit and vegetables , to kill pathogens lurking on the surface ( illustrated ) Scientists at Harvard University in Cambridge , Massachusetts believe that with more research , droplets called Engineered Water Nanostructures ( EWNS ) could replace current methods used to disinfect food , such as applying mild solutions of bleaches and chlorine . ‘ Fruit and vegetables can become contaminated with pathogenic microorganisms anywhere in their production chain , starting from the field or orchard , during harvest , transport , processing , distribution , and marketing , or during preparation in food-service establishments and in the home ( from farm to fork route ) , ’ the scientists write in their study , published in the journal of Environmental Science and Technology . ‘ Possible pathogen sources include contaminated irrigation water , animals , birds , insects , soil , manure , and infected workers/food handlers. ’ Depending on how long fruit and vegetables were exposed to the spray of nanoparticles , lab tests showed that between 80 and 98 per cent of bacteria were destroyed . An SEM image of E. coli is shown . Think of food poisoning and you may immediately consider raw meat to be the culprit . But raw or minimally processed fruit and vegetables can be a source of pathogenic microorganisms , such as bacteria , viruses , and parasites the study said . Every year in the US , approximately 48 million people get sick , 128,000 are hospitalised , and 3,000 die of foodborne diseases . Between 1990 and 2005 , contaminated fresh produce accounted for 13 per cent of all reported food borne outbreaks and for 21 per cent of reported illnesses . In Europe , fresh produce of non-animal origin accounted for 10 per cent of the outbreaks , 26 per cent of the cases , 35 per cent of the hospitalisations , and 46 per cent of deaths between years 2007−2011 , according to the European Food Safety Authority ( EFSA ) . To create the charged droplets , which measure just 25 nanometres , the team led by Philip Demokritou , sprayed water though a strong electrical field - a technique known as electrospraying . The water molecules split into hydroxyl and superoxide radicals , which are usually unstable , Environmental Technology reported . But in the electrospray , a thin layer of charged water captures the radicals and stabilises them . The electrical charge serves to boost each droplet ’ s surface tension so that it stops the radicals evaporating . ‘ EWNS possess unique properties ; they are 25 nm in diameter , remain airborne in indoor conditions for hours , contain Reactive Oxygen Species and have very strong surface charge , ’ the study said . To test the efficiency of process , three strains of bacteria known to cause illness - E. coli , Salmonella and Listeria - were applied to tomatoes and stainless steel surfaces . Tomatoes were then sprayed with nanoparticles in an enclosed chamber for between 30 and 45 minutes , while the steel samples were exposed for 15 to 45 minutes . Scientists believe that with more research , droplets called Engineered Water Nanostructures ( EWNS ) could replace current methods used to disinfect food , such as applying mild solutions of bleaches and chlorine . They tested their technique on tomatoes ( stock picture shown ) Depending on how long fruit and vegetables were exposed to the spray of nanoparticles , lab tests showed that between 80 and 98 per cent of bacteria were destroyed . The study added : ‘ The results presented here indicate that this novel , chemical-free , and environmentally friendly intervention method holds potential for development and application in the food industry , as a “ green ” alternative to existing disinfection methods. ’ The scientists claim that the charged water does not change the taste or texture of food . However , it could be years before it can be used to treat produce sold in supermarkets because current rules stipulate that treatments must kill 99.999 per cent of bacteria .
Experts made droplets using electrically charged water and free radicals . Sprayed onto fruit and vegetables , they can kill up to 98 % of bacteria . E. coli , Americans and Listeria were tested in the experiment on tomatoes . The method could one day replace current ways of disinfecting food .