Protecting families from contaminated food and water
All fields are required
Protecting families from contaminated food and water
Posted in Our Blog on January 16, 2025
Treatment baths for fish should be the future of food safety.
Are we talking about running a lavender bubble bath for your dinner.
Cue the mood music and flickering candles!
Now, THAT would give new meaning to a romantic dinner.
No. I’m talking about decontamination treatment baths for fish at the producer level.
Is that a thing?
Norwegian food scientists think so. Their project is wrapping up now and the results will hopefully be available soon.
Here’s what researchers are studying about treatment baths for fish to reduce Listeria contamination.
The reason this project came about was due to data showing that the presence of Listeria monocytogenes has been found in up to 10 percent of Norwegian salmon slaughterhouses and processing plants. This has resulted in several seafood product recalls related to this pathogen.
This is a big problem.
But what can be done about it?
Scientists believe they have the answer. But it hasn’t been proven safe yet. And so, the idea for the project began. A project funded by FHF – The Norwegian Seafood Research Fund.
In troubleshooting disinfection activities that would be simple for facilities to perform and safe for the consumer, researchers stumbled upon the idea. Can you bathe a fish?
Ok, maybe not in the most obvious way.
But could you dip these fish or their fillets in a bath to remove or inactivate bacteria.
Eureeka!
“In our experiments, we’ve used several methods that aren’t yet approved by Norwegian authorities. That’s the nature of research. If you don’t try new methods, you won’t know what works and what doesn’t. We need to conduct experiments to get results that will either lead to a new method of being approved – or not,” says senior researcher Tone Mari Rode, who leads the DeList research project.
The study entailed first exposing fish to Listeria bacteria. Those contaminated fish were then dipped in various treatment baths. Most of which are already approved on other types of food.
The fish were analyzed to determine which solutions removed or reduced the amounts of bacteria present in the fish fillet.
“We’ve used acetic acid, low pH, and antimicrobial – bacteria-inhibiting – substances. Nisin, which is approved in Norway for use in dairy products, is one of them,” explains Tone Mari Rode.
The goal?
Reduce the Listeria bacterial count by 99.999%.
Is it doable?
Scientists believe so. But they are trying different methods to both remove bacteria and maintain product quality.
In addition to removing measured Listeria contamination, researchers are also monitoring quality. Following different treatment bath protocols, treated fish are compared to untreated control samples.
Scientists will be looking at changes in color and texture as well as microbial communities and pathogen loads. This evaluation is performed shortly after treatment and after typical storage conditions.
“We compared the test fish with trout that hasn’t been dipped in Listeria, to compare what bacteria-inhibing methods do to color, texture, and microbiology – in other words, shelf life. The fish are also stored over time to check the effect the treatment has on the development of both quality and bacterial growth,” explains the project leader.
The project is expected to conclude in January 2025. Details are expected this year.
Results could be a game changer for the seafood industry to reduce waste from recalled product and improve product safety for consumers. Especially when it comes to Listeria. A notoriously dangerous and cold-hardy microbe.
Listeria, in particular, is a problemsome germ.
Once it gets into a facility, it is quite difficult to remove. Does the Blue Bell contamination event ring a bell?
Listeria is hard to kill. It survives refrigerated storage. It can grow in high salt concentrations. And it can even survive drying out and freezing. One of the more effective ways of killing this bad bug is by heat. Specifically, pasteurization.
While many people can experience exposure without getting sick, and some people experience mild illness. For those who experience severe illness, the infection can be life-threatening. Around 15 to 20% of non-pregnant people die from their infection. Those who are pregnant may experience serious complications.
Listeria bacteria cause a complicated range of symptoms. One uniquely dangerous complication affects those who are pregnant.
Initially it poses an intestinal illness, but other potential system-wide problems are experienced if the bacteria leave the digestive system and attack other parts of the body.
One of the most common symptom profiles of Listeria illness involves intestinal illness. Intestinal illness takes place when the bacteria affect the digestive system.
Common symptoms include vomiting and diarrhea beginning within 24 hours of consuming something contaminated with Listeria bacteria. These symptoms often resolve within three days.
Most people with intestinal Listeria illness do not require medical intervention or antibiotic treatment. Plenty of rest, fluids, and treating the symptoms is the most common treatment.
Intestinal Listeria illness can evolve to more invasive illness.
Here’s where things get tricky.
Listeria bacteria cause invasive illness when they leave the digestive system and enter other parts of the body. Invasive listeriosis affects pregnant people and non-pregnant people in different ways. These invasive illness symptoms usually begin about two weeks after exposure.
While personal symptoms of invasive listeriosis are milder in pregnant people, the impact on the pregnancy poses potentially serious consequences. Someone who is pregnant and experiencing invasive listeriosis may have fever, fatigue, and muscle aches. However, listeriosis during pregnancy can lead to still birth, premature delivery, miscarriage, or life-threatening infection in the newborn.
Those who are not pregnant have a higher personal risk of serious illness or death. Invasive listeriosis in non-pregnant people often includes headache, stiff neck, confusion, loss of balance, and convulsions. Some may also experience fever and/or muscle aches. This infection can be serious or even life-threatening. 1 in 20 nonpregnant people with invasive listeriosis will die from their illness.
People who are not pregnant often experience symptoms such as headache, stiff neck, confusion, loss of balance, and convulsions. Fever and muscle aches are also possible symptoms. This type of illness can be serious and life-threatening. Most people with invasive listeriosis require medical treatment and often need hospitalization.
Treatment baths for fish could be coming to a supermarket or fishmonger near you! What are your thoughts on the topic.
Are you concerned about the quality? Residual disinfectant chemicals?
Or are you pleased with the lengths producers are willing to go to keep your food safe?
If you’d like to know more about food safety topics in the news, like “Treatment Baths for Fish Could be the Future of Food Safety,” check out the Make Food Safe Blog. We regularly update trending topics, foodborne infections in the news, recalls, and more! Stay tuned for quality information to help keep your family safe, while The Lange Law Firm, PLLC strives to Make Food Safe!
By: Heather Van Tassell (contributing writer, non-lawyer)