174 | The Nitty-Gritty of Risk Assessments | Food Waste Follow-up |
Staphylococcus enterotoxin root cause revealed (sort of)
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What is a food safety risk assessment (really?);
Outbreak root cause: Staph toxin in salad;
Food Safety News and Resources;
Follow up: Food Waste Reduction;
Food fraud news, emerging issues and recent incidents.
As a food fraud expert, I’m rarely tempted by natural products with bold claims. Like honey which will enhance your sexual health. In this week’s food fraud news, I share the response of European agencies to an alarming trend: aphrodisiac honey that is marketed as a natural product but actually contains undeclared sildenafil (Viagra).
A 20-second search revealed it’s available beyond Europe. I can purchase a pack of 24 sachets of Super Honey for Him - Sexual Enhancement here in Australia for A$119 (US$73).
(I also found a product called ‘Australian Hot Honey’ which sounded sexy but just turned out to be honey infused with Serrano chillies 😄)
Find the fraudulent honey story in this week’s food fraud news.
Also in this issue: brush up on food safety risk assessments, discover the root cause of a salad-related food poisoning event and learn more about food waste reduction initiatives.
Enjoy!
Karen
What is a food safety risk assessment (really)?
We all know what a food safety risk assessment is, right? Well sort of… I thought it was time to brush up on the basics and get down to the nitty-gritty of risk assessments.
What is risk?
Risk is “the effect of uncertainty on objectives” according to ISO 31000 Risk Management. In food safety, we define risk as “a function of the probability of an adverse health effect and the severity of that effect, consequential to a hazard(s) in food” (FAO, 1997).
Put more simply, risk is the chance that something bad will happen.
For example: the probability of a person becoming sick from Salmonella in fruit salad.
What is a risk assessment?
A risk assessment is a scientific process that attempts to determine the size of a risk and the factors that impact it. Risk assessments are performed using data from scientific literature or other high-quality datasets.
How is a food safety risk assessment different to other risk assessments?
While other risk assessments can be broad, and include risks such as financial risks, reputational damage or worker health and safety, food safety risk assessments focus solely on the risks to consumers from hazards in foods. These can be biological, chemical* or physical hazards.
Who does food safety risk assessments (and why?)
Food safety risk assessments are performed by:
experts in academia and government agencies, who use the results to inform the industry of risks, create guidelines and set food regulations.
food safety managers and other qualified individuals in food manufacturing during the development and maintenance of food safety programs.
The 4 steps in a food safety risk assessment
A food safety risk assessment consists of the following four steps, as outlined by the Food and Agriculture Organisation within the Codex Alimentarius Framework ((FAO, 1997).
(i) hazard identification,
(ii) hazard characterization,
(iii) exposure assessment, and
(iv) risk characterization.
In the hazard identification step, the person(s) conducting the risk assessment identify biological, chemical, and physical agents capable of causing illness or injury in a food.
Each hazard is then characterised with respect to the type(s) of adverse health effect and its/their severity. For example, the relationship between consumers being exposed to a hazard such as Salmonella and the likelihood of disease, as well as the severity of disease.
Factors such as the characteristics of the consumers, the virulence of the Salmonella and effects from the food matrix are considered. If enough data is available, a dose-response relationship should be used. This is a mathematical relationship between the size of the dose of a hazard – for example, how many cells of Salmonella are in a serving of food – and the probable severity and/or frequency of the associated illnesses.
The exposure assessment step provides a quantitative measure of how much of the hazard may reach a consumer. The exposure assessment process requires an understanding of how much food is likely to be consumed as well as the probable concentration of the hazard in the food.
Risk characterisation is the final step in the risk assessment process. It combines the findings from the first three steps to create an estimate of the probability (occurrence and severity) of illness or injury occurring based on the hazards identified, their characterisations and the exposure assessment. The estimate can be risk per portion of food or risk per population and may be qualitative, semi-qualitative or quantitative,
See an example of a quantitative risk assessment calculation done with norovirus exposure and consumption of oysters here: Hunt et. al. (2023)
What is the difference between qualitative and quantitative risk assessments?
Quantitative risk assessments use probabilistic modelling to generate numerical estimates for consumer risk.
For example, if fruit salad contains 1 cfu/g of Salmonella, and the average consumer eats 150 g of fruit salad per serve, then the risk might be quantified as 1 illness per 10,000 servings (numbers for illustration purposes only).
A qualitative risk assessment is performed when there is not enough data to perform a quantitative risk assessment. Qualitative assessments make use of descriptive terms such as ‘negligible’, ‘low’, ‘medium’ or ‘high’. The process relies on a subjective description of quantities based on expert opinions.
For example, if the hazard is defined as 25 cfu/g of Salmonella in fruit salad, an expert might say that an illness is likely to occur and the consequences would be moderately severe. As such, the expert might conclude the risk is high.
Qualitative risk assessments are faster than quantitative risk assessments and can be performed to address day-to-day scenarios and make real-time decisions in food manufacturing such as whether or not to release product for sale, accept incoming raw materials or approve a change to a process.
Such risk assessments can be made without detailed analysis and in the absence of probability data, using a risk matrix such as the one below.
Learn more:
The World Health Organization’s Microbiological Risk Assessment Guidance for Food (MRA 36) provides a structured framework for assessing the risk of microbiological hazards in food.
Quantitative Risk Assessments for Allergens explained an on-demand webinar: Watch here (1.5 h)
*For the purposes of this post chemical hazards include allergens and radiological hazards.
Outbreak root cause: Staph toxin in salad 🤔
An outbreak of illness that affected 43 airline passengers last month has been attributed to beetroot salad contaminated with Staphylococcus aureus toxin.
Salads are rarely associated with S. aureus outbreaks, which are more commonly caused by sliced meats, puddings and pastries.
The passengers experienced vomiting, nausea, abdominal pain, and diarrhoea 10 to 60 minutes after consuming an inflight meal containing beetroot salad.
An investigation by food safety officials at the facility where the salad was made discovered a number of preparation steps that involved direct hand contact with salad ingredients.
Staphylococcus aureus is naturally present on the skin of approximately 25% of people. However for it to cause foodborne illness, it must grow in food to produce a toxin. This means the food must first be contaminated, for example by hand contact, then the food must be stored at non-refrigerated temperatures to allow for the growth of the bacteria.
Once the toxin is present in food it is stable at both high temperatures and low pH (Regenthal, et. al. (2017)).
Unfortunately, although the outbreak investigation report explained a possible cause for Staphylococcus aureus bacteria being present in the food - bare-hand contact during salad preparation - it did not explain what went wrong to allow the bacteria to grow and produce toxin.
In short: 🍏 Staphylococcal enterotoxin in beetroot salad has been declared the probable cause of an outbreak of foodborne illness 🍏 Food safety officials attributed the presence of Staphylococcus aureus in the food to bare hand contact in the salad preparation 🍏 The means by which the bacteria could have grown to produce the toxin was not explained by investigators 🍏
Sources:
CDC (2024). About Staph Food Poisoning. [online] Staphylococcal Food Poisoning. Available at: https://www.cdc.gov/staph-food-poisoning/about/index.html.
Info.gov.hk. (2025). CHP completes investigation into clusters of food poisoning among passengers on flights from Nepal. [online] Available at: https://www.info.gov.hk/gia/general/202501/24/P2025012400395.htm
Regenthal, P., Hansen, J.S., André, I. and Lindkvist-Petersson, K. (2017). Thermal stability and structural changes in bacterial toxins responsible for food poisoning. PLOS ONE, 12(2), p.e0172445. doi:https://doi.org/10.1371/journal.pone.0172445.
Food Safety News and Resources
This week’s food safety news features 2 unusual recalls, 3 helpful (free) webinars and followups from the Boar’s Head Listeria outbreak, an allergen death and bird flu’s risk to humans.
Click the preview below to read.
Follow up: Food Waste Reduction
Nearly one-fifth of food produced for human consumption is lost or wasted globally, amounting to one billion meals wasted per day, with 60% of food waste happening at the household level (UN World Food Program).
In Issue 172 we learned how to get maximum impact while reducing food waste.
If you’re striving to reduce food waste at work this year, here are two more resources you might like:
EBook: Sustainability versus Safety
New Food Magazine has published an ebook on the tradeoffs between food safety and sustainable food practices. Called Sustainability versus Safety it draws on expertise from a panel of ten food and beverage experts and addresses key industry questions including:
Is sustainability potentially changing our contamination sources and what we need to test for?
How can we ensure that we discard unsafe food while still meeting our sustainability goals?
The ebook is downloadable with a free New Food account.
EBook: Sustainability versus safety
Expert Roundtable: Food Waste Fundamentals
Experts from the US, Chile, and Germany joined Foodservice Consultant Magazine in December to discuss changing attitudes and behaviours in the management of food waste. A recording is available at the link below.
Food Waste Fundamentals: An FCSI Roundtable
Below for paying subscribers: Food fraud news, research and incident reports
📌 Food Fraud News 📌
In this week’s food fraud news:
📌 Two food fraud trends;
📌 Botanicals insight;
📌 Turmeric - a new unauthorised colourant;
📌 Wow results for shrimp fraud, and more.
Food fraud trend: Aphrodisiac honey
A Belgium news outlet has reported on a “craze” among consumers for libido-enhancing honey, including honey sachets which claim “one packet, one dose” and claiming there is an illicit trade in such products. Other European countries including France, Germany and the Netherlands have also noted a rise in similar products including honey sticks and honey shots.
The products are being sold through
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