155 | Emerging Trends in Food Safety | A Yersinia mystery solved | E-book out now |
Plus, reader insights for food safety hazards
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Reader insight: Intrinsic versus extrinsic hazards;
Emerging trends in food safety (2024);
Yersinia mystery solved - a case study;
Food Safety News and Resources;
Out now: The Rotten Apple e-book, Issues 126 to 150;
Food fraud news, emerging issues and recent incidents.
Hello, lovely readers!
And a special hello to Tania from Australia who just upgraded to a paid subscription, and to Catherine from Ireland and Anna from Poland for renewing. You’re the best 👏👏 thank you for your support 👏👏 I couldn’t make this newsletter without you.
Welcome to Issue 155 of The Rotten Apple. This week has been quiet on the food safety front, there haven’t been any unusual recalls. Instead, the news has been dominated by the fallout from the huge and deadly Listeria-deli-meat outbreak in the USA, after a freedom of information request revealed major sanitation failures at the manufacturing facility. The first lawsuit was just announced: a cool US$10 million is being sought by a woman who spent 6 days in the intensive care unit with listeriosis after eating contaminated liverwurst.
This week’s issue features a case study into a Yersinia enterocolitica outbreak. I confess I didn’t remember that this pathogenic bacterium can grow in the fridge…. some good learnings for hazard analyses there.
Also this week, I revisit physical hazards with a reader insight and wonder about the response of a vodka brand owner to a potentially deadly counterfeiting incident.
Happy reading.
Karen
P.S. Our September meetup is on Thursday afternoon/evening or Friday morning, depending on your location. Everyone is welcome, so come and say hi.
Intrinsic versus Extrinsic Hazards
Reader insight
After I shared my story of swallowing something large and sharp last month, a bunch of you wrote with best wishes (thank you!)
If you missed it, I required emergency surgery after getting a large piece of broken mussel shell lodged deep in my oesophagus while eating spaghetti marina. Ouch.
I discussed the nature of the hazard in my subsequent post. It was mussel shell in a dish containing on-the-shell mussels - a hazard that could reasonably be expected to be present, even without major negligence on the part of the food business. In my post, I compared my feelings about the situation to how I would have felt if I had, for example, swallowed a piece of glass which should not have been in the food under any circumstances.
Reader Chris, of England, responded with a helpful way of thinking about such hazards and provided better language than I could conjure at the time. Over to you, Chris:
“Hi Karen, a great read as usual!
Also, I am glad to hear there was no lasting damage from your experience with an intrinsic foreign body; that is what I call them vs. extrinsic. The term does not judge severity; as you point out, they can both be damaging and a risk. However, in my experience, this categorisation helps people focus on the two types in different ways.
Talk about going beyond the norm in the cause of food safety, though!”
Intrinsic hazards versus extrinsic hazards, yes, of course! That’s super helpful, thank you, Chris. Here are some other examples of intrinsic versus extrinsic hazards:
Physical hazard: olive seeds in pitted olives (intrinsic) versus glass from a broken window in cheesecake (extrinsic).
Chemical hazard: cyanogenic compounds which are naturally present in apricot kernels/seeds (intrinsic) versus fuel oil contamination of bulk edible oil from improper cleaning of tankers (extrinsic).
Microbial hazard: Vibrio vulnificus, a natural marine bacterium found in clean water, in oysters (intrinsic) versus norovirus in oysters due to the presence of human sewerage in harvest waters (extrinsic).
Takeaways for food professionals
Categorising hazards as intrinsic or extrinsic can assist in food safety hazard analyses because food safety teams are able to tackle the two types using different approaches while acknowledging that intrinsic hazards can be just as severe as extrinsic hazards.
🍏 More about physical hazards: Frogs and Other Foreign Objects in Food (Issue 118) 🍏
Emerging Trends in Food Safety (2024)
We’re three-quarters of the way through 2024, which feels like a good time to review what’s been happening in the world of food safety this year, and do a little crystal ball gazing for the coming year.
But don’t despair, this won’t be your typical food safety prediction article, like the ones where pundits predict that industry-wide blockchain for traceability is imminent, that we’ll soon be eating cultured meat and insects by the bucket-load, or that every pack of low-priced food will carry smart-sensors for detecting spoilage. Nope.
Instead of trotting out those tired old predictions that never seem to come true, I want to talk about things I have personally noticed in my weekly scans of hundreds of food industry news items and remind you of the challenges that continue to emerge as we plunge towards the second half of this decade.
Better outbreak investigation results
The most impactful trend I’ve seen this year has been the increasing numbers of tricky microbial foodborne illness outbreaks that are being ‘solved’. By tricky, I mean outbreaks that would not previously have been recognised as an outbreak, but rather as unrelated sporadic illnesses, or perhaps missed altogether.
The existence and sources of such outbreaks are being discovered using whole genome sequencing which can compare the genetic fingerprint of pathogens in patient samples with microorganisms in environmental samples from food facilities, agricultural areas and foods, finding links that would otherwise be missed.
For example, in April 2024, 20 illnesses caused by Listeria monocytogenes which had occurred over the previous five years were able to be linked using genomic data analyses on the microbes isolated from patients and from sliced smoked salmon products from a single manufacturing site in Denmark. The outbreak strain was found in four batches from the same factory between 2021 and 2024 and in environmental samples from within the factory in 2023.
Investigators concluded that the outbreak strain of L. monocytogenes was persisting within the environment of the smoked salmon facility and that the points of contamination had not been adequately identified or controlled.
Such links between samples from different sources, and over long time frames would have been too expensive to conclusively prove until recently, when the cost of genetic sequencing dropped to levels that now allow it to be used for foodborne illness investigations, at least in wealthy countries.
Similarly, epidemiologists in the US were able to link one brand of charcuterie meats to a Salmonella outbreak that affected 104 people across 33 states in 2023 and 2024. A deadly 10-year Listeria outbreak from white cheese was also solved using whole genome sequencing in 2024.
Key takeaway: Food businesses that cause sporadic cases of illness from unhygienic facilities or poor food handling practices are now much more likely to be caught, with whole genome sequencing providing the ‘smoking gun’ linking their products to sick patients.
An increased focus on low-dose chemical hazards
In the past year or so, I’ve noticed an increase in the attention being paid to chemical contaminants and their possible long-term health effects on consumers. The health and wellness industry has been talking about these for decades, but what’s new is that mainstream food industry media is now also covering this issue.
I suspect this is in part because of the stellar work being conducted by the European Food Safety Authority (EFSA) which provides independent scientific advice on food safety risks. Unlike the US Food and Drug Administration (FDA), the EFSA does not make risk management decisions, freeing it up to focus on the scientific aspects of each risk assessment, leaving the European Commission to negotiate the social and political ramifications of managing any risk it finds.
Bisphenol A (BPA) exposure from food packaging is one area where food safety risks are being taken increasingly seriously, at least in Europe. In April 2023, the EFSA revised its safe intake recommendations for BPA down by a factor of ten thousand, and one year on, the European Commission is set to ban BPA in most food contact materials.
Good to know: A ban on BPA in food packaging in Europe could be problematic for businesses that export canned foods and beverages in polycarbonate containers to Europe, since such packages often contain BPA.
It’s not just BPA. Other low-dose chemical hazards which have been getting attention lately include micro- and nanoplastics, lead and cadmium in chocolate, arsenic in rice (especially baby foods made with rice flour) and per- and polyfluoroalkyl substances (PFAS) chemicals in packaging and food.
For example, a study that links exposure to PFAS chemicals in early childhood with the symptoms of attention-deficit/hyperactivity disorder (ADHD) was published last year. Around the same time, calls for the packaging industry to phase out PFASs in food contact materials reached a peak.
Other food contact materials are also getting attention. Just this month, the United Kingdom’s Food Standards Agency issued a warning about the long-terms risks of exposure to chemicals in melamine servingware.
The increased use of recycled plastics for food contact has also raised concerns about contamination of food from chemicals present in the recycled materials.
Insect foods and allergen concerns
As the food investment industry continues to hype insect proteins as a solution to food security and sustainability issues, food safety experts are quietly working to explore the ramifications for allergic consumers. Because insects have chitin exoskeletons, the same as crustaceans such as shrimp and crab, there are allergen cross-reactivities between the two food categories. Work has commenced to understand the allergen profiles of different insect species.
Side note: The most practical use for farm-raised insect protein seems to be as aquaculture feed. Currently, most aquaculture feed relies on wild-harvested fish, leading to serious concerns about overfishing for aquaculture feed production. Terrestrial food sources for aquaculture such as insects, could help prevent overfishing.
Other continuing trends
🦠 Antimicrobial resistance in foodborne pathogens continues to be a growing risk, with every survey of resistance in pathogens finding a significant proportion of samples to be resistant to at least one clinically important antibiotic. This means that bacterial foodborne illnesses will continue to become more difficult to treat and will also be more dangerous to victims.
🌾 Mycotoxin contamination continues to be a concern for certain commodities. With our planet becoming hotter, and some food-growing regions becoming wetter, commodities and regions that didn’t previously have mould problems are increasingly affected by mould and thereby mycotoxin contamination. For example, in the past month there have been 10 European notifications for aflatoxins in nuts and nut products imported from the USA.
🌿 Tropane alkaloid contamination of food crops from weeds appears to be continuing. Some commentators blame a climate-change-induced increase in the number of flood events for spreading the seeds of weed which contain tropane alkaloid toxins. Soy beans and leafy greens have been affected in recent years. The World Health Organisation is calling for data in an attempt to understand the size of the problem.
🦪 Risks from non-cholera Vibrio in seafood are increasing, due to warming seas. Vibrio bacteria are found in coastal waters and can cause foodborne illness from the consumption of raw or undercooked seafood such as oysters and other shellfish. Rising sea surface temperatures in the US and Europe have expanded the bacteria’s habitat, leading to new risks for seafood from those regions. Lately, when experts talk about Vibrio risk their language has changed from “could become more frequent” to “has become more frequent”, with the US Centers for Disease Control and Prevention (CDC) reporting an eightfold increase in Vibrio vulnficius wound infections in the Eastern United States since 1988.
🥛 Unpasteurised milk products are not getting safer. Despite well-known risks and well-understood preventive controls for pathogens in raw milk and raw milk cheeses, the number of illnesses caused by these products has not declined. Recent outbreaks in Europe include Yersinia in raw goat milk cheese and E. coli in morbier, raclette, and tomme cheeses. In the US, consumption of raw milk increased by more than 20 percent in the first months after news of bird flu in dairy cows hit social media. So far, no human cases of bird flu from raw milk consumption have been publicly reported.
Takeaways for food professionals
New hazards, such as new forms of antimicrobial resistance, are emerging and the risks posed by some old hazards are changing. For example, more people may be exposed to mycotoxins in cereal foods and Vibrio bacteria in seafood due to changing weather patterns and ocean temperatures.
In more positive news, our industry is putting more effort into understanding the long-term risks of low concentrations of chemical contaminants in foods. Best of all, we are getting better at discovering the sources of foodborne illness outbreaks, so food businesses that cause illness are now more likely to get caught.
In short: 🍏 Food safety trends for 2024 include more outbreaks solved with genetic techniques, an increasing focus on long-term health risks from chemical hazards and growing knowledge of allergens in insect foods 🍏 Trends that have continued from past years include increasing risks from antimicrobial-resistant pathogens, mycotoxin contamination, tropane alkaloid contamination from weeds, non-cholera Vibrio in seafood, and increasing risks associated with raw milk, particularly related to increased consumption and bird-flu-related risks in the US 🍏
Milkshake mystery solved!
An outbreak in January 2023 in Australian aged care homes caused by Yersinia enterocolitica has been traced and a likely food source has been found. The probable culprit? Nutritional milkshakes, which were fed to elderly residents.
The source is thought to be a contaminated batch of an ingredient in the milkshakes. Epidemiologists used whole genome sequencing (WGS) to link bacteria from the patients to three samples of milkshake.
During the outbreak investigations, it was noted that staff at the facilities were following correct food handling procedures. They prepared jugs of milkshake using pasteurised dairy products. The jugs were stored in the refrigerator for 24 hours until requested by residents, and then discarded if not used.
Yersinia enterocolitica is usually associated with meat, poultry, or unpasteurised milk products. It can grow at refrigerator temperatures.
Five facilities were involved in the outbreak, with at least 55 residents affected by yersiniosis (11 confirmed, 14 probable and 30 suspected cases).
The specific ingredient was not identified but researchers think it was an ingredient also available to the wider community because there were more cases than usual in the community at the same time as the outbreak. However, infection numbers reduced to ‘normal’ baseline levels within a month, suggesting that the source of the outbreak strain of Y. enterocolitica was a single batch of an ingredient, presumably one with a short shelf life.
Takeaways for food professionals
The milkshakes that sickened the patients in this outbreak had been prepared correctly using pasteurised milk, stored in the refrigerator, and unused servings had been disposed of after 24 hours. The pathogen, Yersinia enterocolitica can grow at refrigerator temperatures. Y. enterocolitica infections are usually associated with meat, poultry, or unpasteurised milk. The illnesses seem to have been caused by a contaminated ingredient in the milkshakes, but this ingredient could not be identified by investigators.
Source:
Candice Colbran, Fiona May, Kate Alexander, Ian Hunter, Russell Stafford, Robert Bell, Anne Cowdry, Fiona Vosti, Sharon Jurd, Trudy Graham, Gino Micalizzi, Rikki Graham, Vicki Slinko (2024). Communicable Diseases Intelligence 2024 – Volume 48 [online]. Available at: https://www1.health.gov.au/internet/main/publishing.nsf/Content/CA1DBF11D71F5F3ECA258ADE0019B036/.
Did you know? 🦠 Yersinia enterocolitica 🦠 can grow in vacuum-packed foods, as well as refrigerated foods.
Food Safety News and Resources
It’s been a very quiet week in food safety news. This week’s highlights are an unusual foodborne illness caused by Lactococcus lactis and three free webinars.
Click the preview below to check those out.
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Below for paying subscribers: Food fraud news, research and incident reports
📌 Food Fraud News 📌
In this week’s food fraud news:
📌 Food fraud trends (China);
📌 Authenticity features on counterfeited vodka brand revealed;
📌 Improvements in the number of products adulterated with Sudan dye;
📌 Fraudulent fertiliser.
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