Friendly bacteria could soon be introduced to bagged salad mixes to try to prevent salmonella or listeria outbreaks.
University of Queensland researchers have begun a two-year, $800,000 study in conjunction with Horticulture Innovation Australia, into adding the bacteria ProbiSafe.
It comes after 300 people in Queensland, Victoria and South Australia fell ill in February last year after an outbreak of salmonella in bagged salads and sprouts.
Associate Professor Mark Turner said they would do taste-testing and investigate the cost of adding ProbiSafe, to make it safer and healthier to eat.
They want to commercialise the "friendly" lactic acid bacteria, which inhibits the growth of salmonella and listeria and is naturally occurring in fruit and vegetables.
The lettuce would be washed in a solution containing the bacteria and would stick to it in the packaging during its shelf-life.
"We consume them every day without any negative effects," Dr Turner said.
"We want to increase the level of this bacteria by about 1,000 fold or 10,000 fold."
The researchers would also consider whether they could add other probiotics, already commercially available.
"Instead of putting them in yoghurt or a capsule, we can put it in a bagged salad, and you can have your dose of probiotics that way," Dr Turner said.
The industry has welcomed the proposal, after last year's outbreak impacted growers across the country.
One Queensland farm saw a 50 per cent drop in sales, and general manager Clem Hodgman said it took weeks for consumer confidence to be restored.
"The national sales across the board, all sales, all supermarkets dropped 30 per cent overnight," he said.
"One farm had an incident and the whole industry suffered.
"It was a catastrophic disaster.
"Australia's got a clean, green reputation overseas, so we're already at the forefront of quality fresh food.
"Public safety is paramount and anything that the industry can do to protect the public or make Australian food clean and safe is a good thing."
Growers said the process of preparing ready-to-eat salads was already thorough and expensive, and the cost of adding probiotics would be incidental in the scheme of things.