Scientist challenges belief plant-based food is safer; temperature is key for safe fruit salads

A food safety researcher in Sweden has called for more awareness of the risks posed by plant-based foods.

“There is a naive belief that plant-based food is safer than animal-based food. Plant-based foods are just as vulnerable to the same pathogens we find in meat, fish, milk and eggs,” said Jenny Schelin, a researcher on food safety at Lund University in Sweden.

Schelin said there is a need to increase knowledge and awareness of the risks associated with plant-based foods.

“We have to learn how to cook these new ingredients to avoid food poisoning from lectins in beans that are not properly cooked, for example,” she said. 

“We know a lot about animal-based foods and are well aware of the risk of pathogens being present. This knowledge is not nearly as extensive when it comes to plant-based raw materials, manufacturing processes and ready-to-eat products, which has sometimes led to an underestimation of the risks, including people becoming seriously ill.”

Hygienic design
Plant-based semi-prepared products often require more manufacturing steps, meaning there are several points when something could go wrong, and a contaminant introduced.

Residue from plant-based foods can also be difficult to wash off after production is finished. Among other things, plants contain more fibers that can get stuck in manufacturing equipment, said Schelin.

“This can cause microbiological issues if the residue left over from the previous production run contains bacterial spores that could end up in the product manufactured in the next production run. We need to think about the design of the equipment, and the cleaning methods need to be adapted to the new raw materials that we are now starting to prepare.” 

Schelin said knowledge of food safety must be maintained, expanded and communicated to younger generations — especially as people start eating new foods.

“We live in an incredibly privileged environment where access to water, refrigeration, freezing, energy and safe ready-to-eat food is taken for granted. But this has also made us vulnerable and serves to remind us that more knowledge, awareness and insight are always needed,” she said.

Listeria and energy efficiency study
Meanwhile, scientists have warned that even small deviations in the cold chain can make pre-cut fruit a health risk.  

A study by researchers at the Swedish University of Agricultural Sciences (SLU) found that energy-saving measures — such as raising the temperature during distribution and in store refrigerators — could have serious consequences for food safety. They investigated how Listeria monocytogenes grows in fresh-cut fruit salads (fruit cocktails) under different storage conditions. Findings were published in the journal Foods.

Current guidelines state that fruit cocktails should be stored at a maximum of 4 degrees C and for up to four days in stores.

The fruit cocktail, consisting of pineapple, apples, cantaloupe and red grapes, was inoculated with a strain of Listeria and stored at 4 and 8 degrees C (39.2 and 46.4 degrees F), or a dynamic temperature of 39.2 degrees F for one day and 46.4 degrees F for seven days.

At 46.4 degrees F, the amount of bacteria increased more than ten-fold compared to storage at 39.2 degrees F, which the researchers believe is enough to pose a health risk to vulnerable groups.

“We see a worrying trend where energy efficiency is leading to increased cooling temperatures or shortened cooling times. This can have serious consequences in products such as fruit cocktails, which are not heat-treated,” said Beatrix Alsanius, a professor at SLU and one of the researchers.

(To sign up for a free subscription to Food Safety News, click here)

Source: https://www.foodsafetynews.com/2025/11/scientist-challenges-belief-plant-based-food-is-safer-temperature-is-key-for-safe-fruit-salads/