Iowa State University researchers are targeting leafy greens in an effort to protect older adults from foodborne illnesses. Leafy greens are a common source of contamination in such outbreaks, according to a 2013 report by the Centers for Disease Control and Prevention, and older adults are often most susceptible to severe illness or death.
Leafy vegetables, such as lettuce and spinach, accounted for 2.2 million illnesses of the more than 9 million reported annually in the CDC report. Susan W. Arendt, an associate professor of hospitality management at Iowa State, says with a growing aging population, it is critical to focus on food safety in operations that serve older adults. Proper handling and preparation of leafy greens will help reduce the number of food poisoning cases, she said.
Arendt is leading a team of researchers that spent time observing how foodservice workers at hospitals, assisted living and long-term care facilities, as well as restaurants, handle, prepare and serve leafy greens. Employees were also interviewed about the steps they follow in the kitchen. The research team took swabs of utensils and food contact surfaces at different times throughout the process to measure bacteria levels and contamination.
"We want to make sure leafy greens are served safely. Employees in these facilities are really the last line of defense in protecting against foodborne illnesses. Proper handling of leafy greens is especially important because they are mostly served raw," Arendt said. "We identified several potential problems that could lead to contamination."
The purpose of the two-year study, funded by the USDA, is not to criticize, but to educate employees on how to minimize the risk for cross contamination. Based on their observations, researchers developed a series of posters to use at each facility. The team plans to return to each location for follow-up testing and observations to see if the educational campaign had an impact.
Researchers wanted a simple and effective way to deliver the information to employees who are working in a fast-paced environment. Instead of requiring classroom training or providing material for the employees to read, the posters hit on key messages and use several visuals to make a point. Arendt says the material will be translated into Chinese and Spanish.
"We know that foodservice directors do not have a lot of time to search for materials that are beneficial for their employees. With a minimal amount of text we hope the posters will reach a broad audience, regardless of language or reading skills," Arendt said.
Reminders we can all use
The posters make you stop and think about what you're doing and touching when preparing food, even in your own kitchen. One features images of the germs found on your hands after touching your phone or face, or if your hands are not properly washed. Arendt says those germs can easily be transferred to lettuce or spinach if the food is not handled properly, thereby increasing the chances for contamination.
Another poster illustrates how to handle and store pre-packaged or bagged vegetables – it does not recommend washing the produce after opening the package. It's a precaution many people may take following a 2006 E. coli outbreak linked to bagged spinach. However, Arendt says these items are triple washed and extra handling before serving is an added risk. The Food and Drug Administration also recommends not rewashing, pre-washed produce.
"The importance of safe handling of food is paramount particularly for those at highest risk for a foodborne illness," Arendt said. "Because older adults are more vulnerable to foodborne illness, the result can be deadly."
Iowa State researchers Catherine Strohbehn, an adjunct professor of hospitality management, Lakshman Rajagopal, an associate professor of hospitality management, and Angela Shaw, an assistant professor of food science and human nutrition, are working with Arendt on the project. Kevin Sauer, an associate professor at Kansas State University, is also part of the team.
Explore further: Lettuce: buy bagged or not?