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Peaches Recalled Nationwide After 101 Sickened, 17 Hospitalized Across North America
If you bought peaches at any of the country’s largest supermarkets this summer—including Target, Walmart, and Kroger—you should probably toss ‘em
by Jessica Fu
08.25.2020
If you bought peaches at any of the country’s largest supermarkets this summer—including Target, Walmart, and Kroger—you should probably toss ‘em.
Federal agencies on Monday expanded a nationwide recall of peaches linked to the country’s largest stone fruit company, Prima Wawona, due to potential contamination with Salmonella Enteritidis. The recall, first announced last week, was originally limited to bagged fruit, and has now been extended to individual and loose peaches as well. Both yellow and white, conventional and organic peaches are affected. A full list of recalled products, including specific produce codes, can be found here.
According to the Centers for Disease Control and Prevention (CDC), at least 68 individuals have become sickened by the outbreak strain, Salmonella Enteritidis, and 14 have been hospitalized across nine states. In Canada, U.S.-imported peaches have sickened an additional 33 people in two provinces.
The Food and Drug Administration (FDA) is urging eaters to toss any of the specified fruit purchased from some of the country’s largest grocery chains—such as Aldi, Walmart, Kroger, and Target—between June and August, including peaches you might have in your freezer. It’s also encouraging both restaurants and suppliers to throw potentially contaminated fruit away.
“Salmonella is really sturdy, meaning it’s very good at surviving on plants like fruit and produce.”
Salmonella is a foodborne illness that can cause gastrointestinal issues, ranging from stomach aches to bloody feces. While most infections resolve themselves without treatment within hours or a few days, many eaters—including children, elderly people, and those who may have compromised immune systems—face a heightened risk for serious complications.
There are numerous points along any supply chain where fruits and vegetables can be infected with illness-causing bacteria. This can happen anywhere from farm fields, where animal feces can spread disease to produce; to processing plants that fail to properly sanitize equipment; to one’s own home, where raw meat or eggs can cross-contaminate with other groceries, said Mary Anne Amalaradjou, an associate professor of food microbiology at the University of Connecticut
“All of these factors can play a role in how salmonella can get into food and how it gets into us,” she said. In the past, Amalardjou has studied this particular outbreak strain and its ability to survive in mangos, finding that Salmonella Enteritidis can stay alive inside fruit for multiple days, and can remain on surfaces even after washing.
“Salmonella is really sturdy, meaning it’s very good at surviving on plants like fruit and produce,” she said.
In addition to our peach problem, an outbreak of Salmonella Newport linked to red onions has sickened over 500 people in the U.S. and Canada, and a Cyclospora outbreak linked to bagged salads sickened nearly 700.
For this particular outbreak, FDA and CDC have reportedly traced multiple infections back to Prima Wawona, the nation’s biggest stone fruit supplier.
“We’re conducting this voluntary recall in cooperation with the FDA out of consideration for the wellbeing and safety of our customers and consumers,” said George Nikolich, Prima Wawona’s vice president of technical operations in a press release. “We continue to be committed to serving consumers with high quality fruit.”
This isn’t the first time the company has been linked to foodborne illness. In the summer of 2014, it had to recall peaches, nectarines, plums, and pluots due to potential listeria contamination, food safety lawyer Bill Marler noted for Food Poisoning Journal.
You couldn’t be blamed for feeling like 2020 has been banner summer for foodborne illnesses: In addition to our peach problem, an outbreak of Salmonella Newport linked to red onions has sickened over 500 people in the U.S. and Canada, and a Cyclospora outbreak linked to bagged salads sickened nearly 700.
Outbreaks of foodborne illness occur every year, and advancements in detection technology help officials pinpoint and trace pathogens along the supply chain with increasing efficiency.
Nonetheless, Amalardjou said, there’s no reason to feel too alarmed quite yet: Outbreaks of foodborne illness occur every year, and advancements in detection technology help officials pinpoint and trace pathogens along the supply chain with increasing efficiency.
With peach season in full swing in numerous growing regions, you can likely rest assured that stone fruit produced by other companies or sold at a nearby farmers’ market is still safe to enjoy.
“I’ll still have my peaches,” Amalaradjou said. “I love my peaches.” Safe peaching is just a matter of keeping an eye on FDA’s recall list, and steering clear of any fruit that gets flagged.
We will continue to update this story as it evolves.
Jessica Fu is a staff writer for The Counter.
Lead photo: Jessica Fu
Disease-Causing Bacteria Can Grow on Hydroponic Microgreen Mats
Salmonella enterica and Listeria monocytogenes are two bacteria that can make you sick when eating contaminated produce. It turns out, some microgreen grow mats might be a breeding ground for these bacteria
Posted on July 2, 2020, by Gina Misra
Salmonella enterica and Listeria monocytogenes are two bacteria that can make you sick when eating contaminated produce. It turns out, some microgreen grow mats might be a breeding ground for these bacteria.
You may be like a lot of people and associate foodborne illness with eating improperly cooked meat. Did you know that raw vegetables can also carry foodborne illness? Bacteria and viruses get on produce in a variety of ways: by food handlers, contaminated water, or soil fertilized with untreated manure. Romaine lettuce grown in Arizona made the news in 2018 because of widespread E. coli contamination. Sprouts, another popular health food, have been involved in 74 outbreaks of (mostly) Salmonella since 1973. Turns out these nasty pathogens are not just reserved for chicken and beef! There is no cooking step to kill the bacteria or virus on produce before it goes into your salad. Sometimes washing doesn’t even help, so prevention is key.
Microgreens are a hot new leafy green on the market. A microgreen is the first 2 to 3-inch (5 to 7-cm) tall shoot from a germinating vegetable seed. They are grown indoors in trays or hydroponics systems in soil, soil-substitutes, or without any rooting medium at all. Scientists understand a lot about how bacteria get to leafy greens from soil, but little about contamination in indoor farms. Are indoor farms safer if they don’t use dirt? We wanted to find out.
This is what a typical microgreen hydroponic system looks like. Source: Wikimedia Commons, by Kchittock0511 / CC BY-SA
Microgreen growers do use soil. However, they also use materials such as coco coir (made from coconut husks), Biostrate(TM) mats, plastic, perlite, rice hulls, and hemp in soil-free indoor systems. Our hypothesis was that if soil can transfer bacteria to lettuce, other growing materials can too.
E.coli and Salmonella survived better in hydroponic nutrient solution compared to soil, so we wondered if there would also be differences among soil-free materials. Within the last few years, there have been close to 10 microgreen recalls over diarrhea-causing Salmonella and Listeria monocytogenes found during routine testing. So, we decided to compare the survival of these two pathogens among popular soil-free growing materials to see if the bacteria lived longer on any of them.
An example of a Biostrate mat. Source: The author | Creative Commons Share Alike 4.0
We watered multiple samples of coco coir, Biostrate(TM) mats, hemp mats, and peat-based potting mix and contaminated them with Salmonella and Listeria monocytogenes. To imitate microgreen growing conditions, we left them on the lab bench for 10 days. We took samples from the mats on the first day, and then at 24 hours, 3 days, 6 days, and 10 days to measure the growth of bacteria. Each sample was spread onto Petri dishes containing a gel called agar, enriched with nutrients preferred by each species. The idea behind this classic microbiology technique is that if any cells from the samples were viable, they would multiply on the Petri dishes and form colonies. The colonies are easy to see with the naked eye, and each represents one cell from the original sample.
We found out that Biostrate(TM) mats and hemp mats supported the growth of these two pathogens, while coco coir and peat potting mix did not. In fact, on Biostrate(TM) and hemp, Salmonella and Listeria levels increased after 24 hours and then maintained their original levels for 10 days. On peat and coco coir, Listeria began to die off after the third day and was undetectable on coco coir by the 10th day. Salmonella survived better on all the materials, but on the 10th day, there were 10 times fewer colonies on peat and coco coir compared to the two mats.
Both pathogens showed poorer survival on peat and coco coir compared to no media at all. That means there may be some feature of the peat and coco coir that suppresses the growth of these bacteria. Understanding if that is true, and if so, what exactly that feature is will require more experiments.
It is necessary to point out that because this experiment did not involve microgreens, we still don’t know if microgreens grown in Biostrate(TM) and hemp actually do take up greater amounts of bacteria. These tests are underway! However, this preliminary information may be useful to indoor growers. Until we know more, microgreen growers may want to avoid using fibrous mats, perform additional sanitation steps, or do more testing to keep their customers safe.
Posted in Agriculture, Biology, By Science Writers, By Scientists, Food Science, Microbiology, Science NewsTagged agriculture, Biostrate, coco coir, contamination, food safety, food science, growing media, hemp, hydroponics, indoor farming, leafy greens, Listeria, Microgreens, peat, Salmonella
Study Information
Study published on: May 12, 2020
Study author(s): Gina Misra and Kristen E. Gibson
The study was done at: University of Arkansas
The study was funded by: National Institute of Food and Agriculture, U.S. Department of Agriculture (USDA NIFA) and University of Arkansas
Raw data availability: Available from the author upon request by email.
Featured image credit: Jenny Nichols WallpaperFlare.com