Gas plasmas consist of particles in a high-energy state which are capable of inactivating micro-organisms without the need for chemical solvents or high temperatures.
But a team at the Institute of Food Research in Norwich found that the technique's efficacy in disabling Salmonella Typhimurium depended on the surface features of the fruit or vegetables being treated, with bacteria able to "hide" from the plasmas in the pores of lettuce leaves or the cell walls of potatoes.
That meant the length of exposure time required varied depending on the type of produce, though all took longer to treat than a synthetic surface. By contrast, other factors such as ambient temperature or growth stage of the Salmonella did not affect the required treatment time.
According to one of the team, Dr Arthur Thompson: "The results suggest scaled up devices or combinations with other mild treatments could provide a very effective solution for destroying bacteria with little or no effect on the produce itself. But it will be important to take into account the type of food and its surface structure."
The results are published in the current Food Microbiology.