217 | Introduction to an illegal colourant | Tomato paste dramas | Glove safety
Plus a free food fraud e-book
This is The Rotten Apple, an inside view on food fraud and food safety for professionals, policy-makers and purveyors. Subscribe for insights, latest news and emerging trends straight to your inbox each Monday.
Introduction to an illegal colourant: Auramine O
Tomato paste: ripe for fraud
Are PVC gloves unsafe?
Prodded, poked and punctured (Just for fun)
Food Fraud News and Recent Incidents
Hello everyone,
Welcome to The Rotten Apple. If you’re new here, I’m Karen and I spend hours each week trawling the interwebs so I can keep you up to date with the latest knowledge in food safety, food fraud and sustainable supply chains with not-boring, ad-free articles and news roundups.
This week’s issue is heavy on food fraud, with an introduction to an illegal adulterant and insights from a food fraud expert into an unfolding commodity crisis. Plus, do PVC gloves really pose a significant threat to public health?
Karen
P.S. This independent publication is made possible by my paying subscribers. If you value high-quality, ad-free content and want to join hundreds of happy supporters, please consider upgrading to a paid subscription today. It costs less than $2 per week and is tax-deductible if you work in/with food*.
*(probably! 😉)
Introduction to an illegal colourant: Auramine O
Illegal colourants are a major food fraud problem and an important source of food safety hazards in fraud-affected foods.
Reminder: many food frauds do not pose threats to food safety but are instead related to false claims made about foods or ingredients. However, economically motivated adulteration is a subset of food fraud that poses serious risks to consumers.
Economically motivated adulteration occurs when a person adds a substance to food to enhance its perceived value and does not declare its presence. Adulterants can be used to mask signs of spoilage or improve the apparent quality, flavour or freshness of the food. Adulterants are also used to increase weight or volume so the perpetrator receives more money when the food is sold.
Illegal colourants are just one of many types of adulterants used for economic gain in food fraud.
I’ve explored a few different illegal colourants in The Rotten Apple over the years – from lead chromate in turmeric and cinnamon to Sudan dyes in paprika, but the subject of this article, Auramine O, is new to me.
For the record, I’m using the term ‘illegal colourant’ to refer to any dye, pigment or optical brightener added to food but not permitted for use in food. Unlike approved food colours, these substances are often toxic and can be contaminated with dangerous impurities.
However, it’s worth noting that even ‘legal’ and safe food colours can be considered food fraud adulterants if their presence is not declared, expected or explicitly allowed in a food or ingredient.
What is Auramine O?
Auramine O is a bright yellow diarylmethane dye, sometimes called canary yellow, used to colour textiles, leather, paper, straw and rayon goods, as well as in printing inks, ballpoint pen pastes, and as a fluorescent stain in microbiology.
In India and other manufacturing hubs, it is produced in bulk for the textile and ink sectors and sold through chemical wholesalers and informal markets at very low cost, making it readily available to food producers and unethical middlemen who may sell it as legitimate food colouring.
The International Agency for Research on Cancer (IARC) has classified auramine as possibly carcinogenic to humans (Group 2B), based on evidence of bladder cancer in exposed workers, and toxicology studies that link it to liver, kidney and spleen damage and mutagenicity
Which foods are affected?
Auramine O is used as an illegal, undeclared colourant in yellow-coloured foods, particularly foods where colour strongly influences perceptions of quality or flavour.
A social media video (below) that claims to show auramine O being added to chana (roasted chickpea snacks) went viral in India recently, prompting outrage from public figures.
Other susceptible foods include:
curry powder,
turmeric and curcuma preparations,
bamboo shoots,
brightly coloured sweets,
savoury snacks,
chickpea snacks and dishes (chana),
saffron and
Researchers found auramine O in a significant proportion of food samples (n = 211) purchased from markets and grocery stores in Vietnam in 2018 (Tran-Lam et al (2020)). The tested foods included sour bamboo shoots, chicken, sour cabbage, turmeric powder, curry powder, and satay.
Around one quarter (27%) of the samples contained detectable levels of auramine O, at concentrations of 3.2 μg/kg to 13,024 μg/kg, while 13% of samples contained more than 100 μg/kg.
Four food types - chicken, sour cabbage, sour bamboo shoot and turmeric - tested positive for auramine O with the dye at rates of approximately 30% of samples (n = 33, 56, 45, 15, respectively). The most contaminated sample was a chicken sample that contained 13,024 μg/kg. Chicken also had the highest mean concentration at 2,788 μg/kg across the 33 samples, closely followed by sour bamboo shoots. The type of chicken (raw, cooked, or prepared) was not described. Curry powder and satay were affected less often, with 22% and 14% of samples testing positive for auramine O.
Auramine O has been mentioned in two notifications in RASFF, the European Union’s Rapid Alert System for Food and Feed, since 2015: one notification for its presence in food colouring powder imported from India and one for auramine O found in cumin (cuminum cyminum) imported from India.
Here’s a weird fact about auramine O…
Auramine O is said to pose a health hazard in rural India because of its widespread use in synthetic cow dung. Researchers found it in multiple brands of synthetic cow dung, which is used in place of genuine cow dung in rural areas of India, “primarily for domestic cleaning purposes”.
News summaries from India describe Auramine O adulteration as a “persistent” food‑safety issue; however, I found just one published study examining the presence or prevalence of the dye in foods: Tran-Lam et al (2020).
This could be due to the difficulties of extracting the dye, which is cationic and binds strongly to certain foods. A number of recent research papers discuss methods for detecting and quantifying auramine O in foods, without providing evidence of its widespread use, other than citing Tran-Lam et al.
For example, a 2021 paper discusses methods for recovering auramine O from spiked samples of the herbal medicine bullrush pollen (Typha orientalis), another for detecting it in spiked samples of bean curd, candy and curry powder using carbon nanodots and another paper describes methods for detecting it in Durian.
Key takeaways for food professionals
Have I just given you a new hazard to be concerned about?
Maybe.
However, the vulnerabilities associated with auramine O are very similar to those related to other industrial colourants used to adulterate food, such as lead chromate and Sudan dyes, so mitigations will be similar or identical.
Foods that are yellow-coloured, and food colouring preparations, particularly those from regions where cheap industrial and textile dyes are easily available, are most likely to be affected. Food and ingredients (food colouring powder) from India and Vietnam have been found to contain auramine O.
Mitigations for auramine O adulteration include strong supplier approval processes combined with supply chain verification backed by robust purchasing specifications, targeted analytical testing for high‑risk yellow ingredients such as turmeric, curry powders, spice blends and sweets from at-risk regions, and horizon scanning for signals of increased detections, such as import alerts or RASFF notifications.
In short: Auramine O is a carcinogenic, bright yellow industrial dye which is not authorised for use in food 🍏 Foods and ingredients, including colour preparations, that are valued for their intense yellow colour are vulnerable to fraudulent adulteration with auramine O, especially those from countries where industrial dyes are easily available 🍏 Mitigations are as for other non-food dyes: strong supplier approvals processes + supply chain verification backed with systematic inspection of materials upon receipt and targeted analystical testing 🍏
Main source (others are hyperlinked inline):
Tran-Lam, T, Hong, T., Le, G.T. and Luu, P.D. (2020). Auramine O in foods and spices determined by an UPLC-MS/MS method. Food Additives and Contaminants Part B, [online] 13(3), pp.171–176. doi:https://doi.org/10.1080/19393210.2020.1742208. Full text available from: https://www.researchgate.net/publication/340387641_Auramine_O_in_foods_and_spices_determined_by_an_UPLC-MSMS_method
Tomato paste dramas
In December 2024, allegations of forced labour in the tomato puree supply chains of major British retailers caused shockwaves in Europe.
On the surface, the allegations appeared massively shocking. Firstly, the purees were portrayed as the products of the torture and abuse of Chinese religious minorities. Secondly, the news coverage implied large-scale fraud with respect to the origin of the purees, many of which were marketed with the word ‘Italian’ on the pack.
It seemed that British and German supermarkets were selling ‘Italian’ tomato purees that contained Chinese tomato puree supplied by companies that relied on forced labour.
Shocking.
But when I sat down to share the news with you in Issue 168, I found the legal situation was so murky that I actually couldn’t pin a definite ‘food fraud’ label on any of it.
The BBC, reporting on the issue, used very careful language when referring to the allegations, saying “[some products] are likely to contain Chinese tomatoes” and asserting that “most Chinese tomatoes come from the Xinjiang region, where their production is linked to forced labour by Uyghur and other largely Muslim minorities.”
Most of the details that would have helped to reveal whether this was a case of food fraud were not shared publicly or were not known to the BBC at the time. For example, we weren’t told how much Chinese puree was in any of the products – were they 100% Chinese or only 50%, for example?
We could not decipher the degree of fraud (or not) related to the ‘Italian’ claims, since the BBC did not share the exact claims on the packs of products that were found to contain some Chinese tomatoes.
And finally, while the BBC published interviews with workers who had picked tomatoes under forced labour conditions in China, the information it published was not direct evidence of forced labour in the supply chain of any of the puree products mentioned in the story.
Aside: The most compelling part of the 2024 story, for me, was that one of the Italian manufacturers that supplied some British supermarkets, the company that made ten of the seventeen samples which contained Chinese tomatoes, had previously been accused of fraud by Italian authorities for falsely claiming its products contained ‘100% Italian tomato’.
That’s right, the Italian company supplying ‘Italian’ tomato puree that allegedly contained Chinese tomatoes had been accused of fraud by Italian food authorities three years prior.
Background checks, anyone? A simple Google search of the company name followed by the word tomato revealed instant red flags: two of the top three search results were stories about the company’s 2021 brush with Italian food fraud investigators.
Fast forward to 2025. We are now one year on from the BBC report. And, until last month, all seemed quiet on the tomato paste front.
Not so.
The tomato paste market underwent a huge upheaval following the BBC investigation. Suddenly, everyone was paying attention to the origin of their tomato paste. No one wanted tomato paste from China and the Italian paste suppliers who had been importing it for use in their products stopped buying it.
In the months that followed, Italian processors reduced imports of tomato concentrate from China by 76%, according to the CEO of Mutti, a leading Italian maker of tomato purée and passata, leaving China with a huge stockpile of 600,000 to 700,000 tonnes of tomato paste, equivalent to around 6 months of exports.
Tomato News reports that while Chinese tomato exports to Western Europe and Italy have fallen dramatically, the surplus is being taken up by countries in Eastern Europe, Central America, and the Far East. Production in China has also fallen dramatically, with less than half the volume of tomatoes expected this year compared to 2024.
So, with China no longer supplying major markets in Western Europe, where will those markets get their tomato paste - that all-important ingredient for pizzas, pastas, ready meals and soups?
Can Italian tomato growers step up production to meet demand? Or will the supply-demand gap be so large that fraud becomes almost inevitable?
Food authenticity expert Professor Chris Elliott believes the current situation is ripe for fraud, suggesting the following scenarios are possible:
The large stockpile of tomato paste in China could be transhipped or reprocessed in third countries to conceal its Chinese origins, making it palatable for Western European markets.
Other false claims of origin could be made about tomatoes from other major growing areas such as Spain, Portugal, Chile and Iran.
Lower-quality paste may be blended into higher-value pastes (noting this is not fraud unless accompanied by deceptive claims about quality or origin).
Undeclared fillers and diluents, such as starches or sugars, could be used to extend the volume of scarce non-Chinese tomato paste.
Undeclared and unauthorised colourants could be added to enhance the appearance of low-quality, diluted or age-degraded pastes.
With tomato paste having a long shelf life, these fraud risks will remain for as long as surplus stock remains in China and while European market demand is unsatisfied. And that could be for years to come.
Key takeaway
We are currently in a perfect storm for tomato paste fraud. There is an oversupply of Chinese-made tomato paste and an undersupply of genuine Italian tomato paste. This creates vulnerabilities, particularly for products marketed with specific country of origin claims. Possible frauds include transhipping and reprocessing to disguise the true origin of Chinese pastes, other false origin claims, blending, dilution, addition of fillers and other adulterants to extend the volume or enhance the apparent value of low-quality pastes. Also note that Chinese-origin tomato pastes have been linked to labour violations and modern slavery.
Read more:
🍏 Tomato Puree Fraud by Big Name Retailers? | Issue 168 🍏
🍅 Professor Chris Elliott | The Tomato Shockwave | New Food Magazine 🍅
See also:
This week’s food fraud news includes seizures of tomato paste labelled with a false country of origin - you’ll never guess where!
PVC gloves unsafe?
The American glove company, Eagle, has continued its advocacy for nitrile and polyethene gloves by petitioning the US FDA to ban polyvinyl chloride (‘vinyl’, PVC) gloves for food handling in the United States.
They argue that PVC gloves present “consistent risks to food safety and public health”, due to the presence of phthalates in the gloves – using the term ‘poison plastic’ for PVC in their submission to the FDA - and claim that micro-punctures in food handling gloves lead to “food safety risks”.
The petition also claims that “Multiple studies have documented inconsistencies, including mislabeled ‘phthalate-free’ vinyl gloves that contained phthalates”, providing as evidence a link to a document (Olson et al., 2019) that does not directly address false ‘phthalate-free’ claims.
Source:
Petition: Eagle Request to Prohibit PVC Gloves for Food Handling | FDA
See also: 🍏 Dirty Gloves Straight from the Pack (Are food-handling gloves more hazardous than we imagined?) | Issue 147 🍏
Prodded, poked and punctured: Tomatoes share all (Just for fun)
Meet the world’s most traumatised tomatoes in this 2-minute video for bruised produce. 100% safe for work.
Below for paying subscribers: Food fraud news and incident reports
📌 Food Fraud News 📌
In this week’s food fraud news:
📌 Free food fraud e-book
📌 Company executives arrested over chocolate and sugar composition issues
📌 Method: X-ray fluoroscopy for the origin of seafood
📌 Warnings for tomato paste, supplements, white fish.
Food Fraud Protection: 5 Key Drivers Threatening Food Safety & Quality
A new e-book, written by the respected food fraud specialist Dr Karen Everstine, is now available for free download. It explores the rising risks of food fraud, its impact on businesses, and the steps quality assurance professionals can take to protect food from food fraud. Available from FoodChainID. (An email address is required for download.)