182 | Food Defence in Fresh Produce | Dangerous Cheese |
Plus, self peeling bananas
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Self-peeling bananas;
Food defence for fresh produce;
Strawberry wars;
Blue cheese moulds and mycotoxins;
A humorous history of fruit and veg breeding;
Food fraud news, emerging issues and recent incidents.
Eid Mubarak!
Welcome to Issue 182 of The Rotten Apple, where I celebrate the 1st day of April with a sciencey story about bananas.
Also: what does food defence look like for fresh produce? Growing, packing and processing operations have unique vulnerabilities. Plus, more about the ‘safe’ moulds in blue cheese which might have a secret dark side.
As always, there’s food fraud news for paying subscribers at the end of the issue, plus a humorous history of fruit and vegetable breeding by Sam O’Nella (almost safe for work).
Enjoy!
Karen
Breaking News: Scientists Discover Self-Peeling Bananas
From the news desk, 1st April 2025
In a groundbreaking development, researchers at the University of Tropicana have announced the successful cultivation of self-peeling bananas. These revolutionary fruits, dubbed "AutoPeel Bananas," are said to shed their skins automatically when they reach peak ripeness.
Dr. Chiquita Cavendish, lead botanist on the project, explains: "Through careful genetic modification, we've created bananas that develop microscopic 'unzipping' cells along their peels. When the fruit reaches optimal ripeness, these cells activate, causing the peel to split and curl away from the edible portion."
The AutoPeel Bananas are touted as a solution to reduce food waste and make fruit consumption more convenient. Video footage shows the bananas dramatically unfurling their peels, revealing perfectly ripe fruit inside.
Agricultural experts predict that these self-peeling bananas could revolutionize the fruit industry. Supermarket chains are already vying for exclusive distribution rights, with some planning to install special ripening chambers to trigger the peeling process on demand.
However, some critics have raised concerns about potential mishaps, such as premature peeling during transport or bananas suddenly disrobing in shoppers' bags. The research team assures that fail-safe mechanisms are in place to prevent such occurrences.
It remains to be seen how the public will react to this peeling revelation. Will they slip up and believe it, or will they quickly spot the appeal of this fruity tale?
Food Defence in Fresh Produce
Food defence is a systematic process that aims to protect food from malicious adulteration, such as acts of terrorism, disgruntled employees or extortion.
Much of the information about food defence is targeted at food manufacturing systems. Food defence resources rarely describe food defence in the context of fresh produce - fruit and vegetables.
During the growing, harvesting, processing and packing of fresh produce, fruit and vegetables are vulnerable to attack, as evidenced by the ‘needles in strawberries’ incidents in Australia in 2018 (more on that below).
However, fruit and veg are often considered low risk when it comes to food defence because it is physically difficult to distribute adulterants through whole fresh produce in the quantities needed to pose a large-scale threat to public health.
However, if fresh produce does become adulterated, there is a high chance the adulterant will reach consumers without being detected or deactivated due to the low number of control points and processing steps between the field and the home.
While typical food defence plans are built around ‘key activity types’ (KAT) - operational steps where large quantities of dangerous adulterants could be introduced to bulk food - plans for fresh produce must also address the possibility of deliberate contamination during growing and post-harvest treatments.
For example, if irrigation water, liquid fertiliser or legitimate pesticides were deliberately dosed with highly toxic chemicals, natural toxins or pathogenic organisms, the produce grown or treated with them could present significant risks to consumers. Similarly, post-harvest washing, spraying and waxing operations could also introduce adulterants to the fruit or vegetables.
Types of food defence hazards in fresh produce
Biological hazards: pathogenic organisms and viruses.
Chemical hazards: allergens, pesticides, cleaning agents, mycotoxins, neurotoxins, pharmaceutical drugs, veterinary medicines, other hazardous chemicals, radioactive materials.
Physical hazards: Metal, brittle plastic, glass, razor blades, needles, stones, splinters.
Vulnerabilities at growing sites
Growing sites for fruit and veg, such as fields or orchards are often relatively insecure, with easy-to-circumvent site security like low barrier gates and fences. Due to their remote locations, people intending to cause harm may have more time to perpetrate attacks on growing sites while remaining undetected compared to activities on other food sites.
Such harms could take the form of:
contamination of irrigation water,
tampering with irrigation or fertiliser equipment,
the addition of toxic chemicals to fertilisers or herbicides.
Vulnerabilities at packing sites
The number of vehicles coming and going on packing sites can make access difficult to control. Product receival processes, in which large volumes of fresh produce are unloaded from multiple vehicles, could allow for the introduction of adulterated produce or the introduction of adulterants to bulk lots of produce, without such actions being detected.
Insiders could also contaminate produce during on-site handling.
Where processes such as washing, grading, sorting and waxing occur, potential attacks could target wash water, sanitisers, and the adulteration of post-harvest treatment chemicals such as fruit waxes. Equipment could be tampered with.
Vulnerabilities for fresh-cut produce and other ready-to-eat products
Operations that are high risk for food safety, such as the production of cut fruit and veg, sprouts or ready-to-eat leafy greens usually operate certified food safety management systems. Access to such sites is tightly controlled, meaning attackers on these sites are more likely to be insiders.
Any process step where an adulterant could be added such that it would be distributed throughout a large quantity of product is vulnerable in ready-to-eat produce processing. Such steps include mixing, the addition of ingredients, and bulk liquid handling.
As with minimually processed fruit and veg, the water on such sites is vulnerable to tampering and adulteration.
Food defence mitigations for fresh produce
Limit access to the whole site and control access to critical areas
As with all food defence operations, the first line of defence is to prevent unauthorised people from accessing the site, by establishing a controlled perimeter, idealy with secure, visible fencing. While this is potentially difficult at some growing sites, it should be achievable for high-intensity growing operations, such as hydroponics or glasshouses, and for packing and processing sites.
The second line of defence is monitoring and controlling access. Use security cameras that capture, monitor and record activity in areas that are not under constant observation. In processing facilities, conventional closed circuit television systems can be used, while long-range systems are required for on-farm surveillance.
Control access for vehicles entering the perimeter so that visitors and any other unauthorised persons cannot enter the site or move around it unobserved.
Check the identification of visitors and delivery drivers and always accompany visitors while they are on site.
Implement a system of positive identification, in which only employees and contractors with the correct ID are allowed into vulnerable areas. Positive identification systems can include security passes, badges or printed hi-vis vests or uniforms labelled with the site name.
Inside the perimeter, consider the risks posed by insiders in addition to unauthorised visitors. Prevent workers from taking personal items into critical areas. Store chemicals, including fertilisers, herbicides, pesticides, cleaning chemicals and sanitisers in locked cabinets. Prevent access to water sources such as tanks and view-ports with physical barriers such as fencing and locks.
Set up systems to restrict access to critical areas, equipment and materials so that only personnel who require legitimate access can reach these areas. Ensure that equipment for irrigation, spray applications, washing, post-harvest treatments, pre-packing and processing is secured and inaccessible to unauthorised persons – anything that would allow for the introduction or distribution of an adulterant through the product should be considered critical.
Side bar: Needles in strawberries
In 2018, sewing needles were discovered inside whole fresh strawberries sold in supermarkets in Australia, sparking nationwide media attention, public panic and recalls.
The first incident was traced to a packing house near Caboolture in Queensland, which packed strawberries under two brands. Two months later, a supervisor at the site was charged with contaminating goods with intent to cause economic loss. Her DNA was reportedly found on a contaminated punnet of strawberries.
Within days of the first incident, needles were being found – or allegedly found – in other brands of strawberries grown in other parts of the country and even in apples and bananas. Many incidents were later revealed to be copycat incidents and some were hoaxes, with at least one person arrested for faking contamination.
In total, 186 reports of contamination were recorded across Australia in the two months following the first report, and one incident was recorded in New Zealand in connection with Australian-grown strawberries.
Tonnes of strawberries were dumped when contamination was discovered. A farm in Caboolture, 2018, with piles of dumped produce, via News.com.auCuriously, under US definitions, the needles in strawberries incidents would not fall within the intentional adulteration rule - the rule which requires food defence plans for food businesses. This is because the rule is targeted to incidents that could have large-scale public health impacts.
Only one person was confirmed to have been injured in the strawberry-needle saga. That’s not exactly a large-scale public health event. On the other hand, plenty of people were worried about strawberries in the months following the first reports. Perhaps it could be considered a large-scale mental health event.
So the most famous food defence incident for fresh produce does not even fit within the (US) legal remit for food defence activities? Crazy, huh.
Also crazy is that the perpetrator may not have been a disgruntled employee, as was originally suggested by the Queensland Strawberry Growers Association.
At around the same time as the needle incidents, a separate report published by investigative journalists revealed that Donnybrook Berries, one of the strawberry brands caught up in the scandal, which was in the same locality as the site of the first contamination incident, was owned by a convicted drug trafficker with alleged ties to organized crime. In fact, the convicted criminal had invested more than A$6 million in strawberry farms and properties in the region, suggesting serious criminal influence within the strawberry-growing industry in Caboolture at the time.
There is no evidence that these criminal connections were related to the needle contamination incident. Strangely, however, the supervisor who had allegedly contaminated the strawberries had all charges against her dropped on the first day of her trial, which did not start until three years after the incidents occurred.
When announcing the charges would be dropped, the judge did not elaborate, simply saying that the prosecution would not proceed with the charges against her. The defendant, who had maintained her innocence and spoke almost no English, had been living in hiding for the three-year period between being charged and the trial, with a friend saying, “She’s been scared to go anywhere”.
Possible criminal activities in the strawberry growing industry, a long lead time to trial and the abrupt dropping of charges…. it all seems quite mysterious to me. Perhaps there is more to this story than a simple case of a disgruntled employee seeking to harm their employer.
Other incidents involving fresh produce include one in 1978 in which pro-Palestinian activists injected Israel-grown oranges with liquid mercury with the stated aim of sabotaging the Israeli economy. Contaminated oranges were found in five countries. Another incident involved Chilean grapes imported to the United States. The grapes had been injected with cyanide by a group opposed to the Chilean dictator (source).
Monitor and inspect incoming materials
For fresh produce operations, incoming materials could cause adulteration in produce. For example, agricultural chemicals, wash chemicals, or loads of fruit or veg could have been tampered with, introducing adulterants to the site, equipment, water systems and products.
When receiving deliveries of incoming materials, check load documentation and inspect packaging and container seals for signs of tampering before unloading vehicles.
Monitor distribution and transport
If your business is responsible for distribution, be aware of incidents that may happen after the produce has left your site. This can include tampering during transport, including while trucks are parked en route. Consider using GPS trackers to monitor the location of shipments and be alert to unscheduled stops.
Threats from insiders
Finally, take care with people who are authorised to be on-site, such as employees, labour-hire workers and professional contractors like pest controllers. These ‘insiders’ are well-placed to commit adulteration.
Check the identification, credentials and references of new hires before employment commences. Arrange work tasks so that workers do not work alone but rather in teams or pairs.
Monitor staff morale, because disgruntled employees present a higher risk.
Create an anonymous whistleblowing system where staff can report their concerns.
Foster a culture of awareness and action
Finally, and perhaps most importantly, train your workers about food defence, encourage them to be alert to potential vulnerabilities and to report suspicious activities. Conduct mock incidents to test the food defence plan and practice crisis management protocols such as recalls.
Takeaways for food professionals
Food defence guidance is rarely tailored to fresh produce operations, such as growing and harvesting. The guidance presented in this article is specifically for fresh produce and is based on a fact sheet created by the Fresh Produce Safety Centre Australia & New Zealand. It is relevant to fresh produce operations globally.
As with all food defence systems, the aim is to be alert to the possibility that bad actors may try to add dangerous contaminants to food. For fresh produce, adulteration can happen directly, as occurred with needles in strawberries in 2018, but can also be perpetrated using agricultural systems, such as deliberately contaminated irrigation water, fertilisers or pesticides. Wash water, wash chemicals and post-harvest treatments such as anti-fungals or waxes are also points of potential adulteration.
Mitigating the threats requires systems to keep unauthorised people away from produce, inputs including water and chemicals, and equipment. Checks on incoming materials for signs of tampering or adulteration and minimising vulnerabilities during distribution and transport are also important to mitigation.
Finally, threats posed by insiders should also be considered in a food defence plan for fresh produce. A site-wide culture of awareness is a must for preventing and detecting incidents of intentional aduleration.
Main source:
Fresh Produce Safety Centre Australia & New Zealand (2021) FACTSHEET – FOOD DEFENCE FOR THE FRESH PRODUCE INDUSTRY. Available online at: https://fpsc-anz.com/wp-content/uploads/2021/12/FPSC-FactSheet-Food-Defence.pdf
Other sources are hyperlinked in-line.
Blue cheese moulds can be dangerous under certain conditions
Throwback Thursday Monday
In Issue 87 I talked about good mould and bad mould in food production and shared the fascinating and slightly scary information that Penicillium roqueforti – the mould that gives blue cheese its distinctive flavours and colours – can produce harmful toxins under certain conditions.
New research has revealed that plant-based cheese analogues innoculated with P. roqueforti become contaminated with toxins produced by the mould. These toxins include roquefortine C, andrastin, mycophenolic acid and fumigaclavin A.
The researchers attribute their findings to the higher C/N ratio (presumably carbon to nitrogen, though this is not stated in the paper) of plant-based milks, saying this makes them more likely to promote mycotoxin production than dairy milk with its lower C/N ratio.
The research also revealed that toxin production varies from strain to strain, with some strains of P. roqueforti more likely to produce certain mycotoxins than other strains. The type of plant base used for the cheese analogue also influences which toxins are formed and in what quantities, with the researchers sharing results for cheeses made from almond, cashew, soy, cow and sheep milks.
Learn more here:
Gauthier, O., Bernillon, S., Khireddine, R., Saupique, C., Gallegos. N., Callon, C., Chassard, C., Richard-Forget, F. (2024). Use of Penicillium roqueforti in plant-based veined-blue cheese: a source of mycotoxin hazards? Food Control, pp.111130–111130. doi:https://doi.org/10.1016/j.foodcont.2024.111130.
A (humorous) history of fruit and veg breeding
“But hey”, says YouTuber Sam O’Nella, speaking about the seed-filled, unappetising fruit of the ancestor of the modern banana, in his masterful video Why Produce Used to Suck, “if you stick that boy in the ground you’ve got an okay chance of making a new banana tree.
“[On the other hand, if] you bury a modern banana, all you’re going to end up with is a dirty banana. And not that one club in Miami, I mean an actual dirty banana.”
The ancestor of the eggplant (aubergine), he says, has fruit that resemble little green berries, the size of grapes. “The only thing it seems to have in common with the classic purple eggplant is how little both of them have in common with an egg”.
Click the link below to watch (it’s almost safe for work).
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