She said the company completely rebuilt the facilities after consulting with experts in sanitization and areas of other food safety. Gills Onions is open again and rebuilding its customer base.
“They didn’t just look for one smoking gun, they initiated a top-down investigation,” Parker said. “We focused on quality over speed. To say we took things down to the skeleton would be an understatement.”
That kind of commitment is what you need to win the war against listeria, said Martin Wiedmann, professor and director of graduate studies for food science and technology at Cornell University.
Wiedmann explained how listeria is difficult to eradicate because of its prevalence in nature and its ability to multiply in refrigerated conditions. He said he has documented the presence of a single species of listeria in facilities from three months to 12 years.
“All outbreaks associated with it are linked to long-term presence,” Wiedmann said, adding that the pathogen’s ability to hang on is what makes a search for the root cause mandatory.
Wiedmann also said additional research such as that funded by the Center for Produce Safety is needed to better understand where listeria is most likely to occur so that growers can avoid planting there.