The Top Three Food Frauds and how Nuclear Scientists can Help Detect them

By comparing stable isotope ratios, scientists can distinguish between authentic and adulterated foods and identify mislabelling of a food’s geographical origin and false claims about the production process. Stable isotopes are measured using isotope ratio mass spectrometry, and very small differences in the ratios of the heavy and light forms of isotopes can be detected. These ratios are like nature’s ‘fingerprints’, or signatures, on food. This hidden evidence can be used to determine whether the foods we buy contain the ingredients listed on the label, or whether they have been falsified.

Selvarani Elahi, Deputy Government Chemist for the Government of the United Kingdom and Executive Director of the Food Authenticity Network (FAN), emphasizes the network’s collaborative effort to prevent food fraud: “By leveraging the free information, training and tools available through this global network, countries can enhance their capabilities to detect food fraud and mitigate their vulnerability to it.” FAN facilitates collaboration between scientists, the food industry, government bodies and academia.

Among the food products most affected by food fraud are olive oil (valued for its beneficial effects on the heart); seafood (sought after for its omega-3 essential fatty acids); and honey (prized for its natural sweetness and health-enhancing properties).

Olive oil can be adulterated with cheaper alternatives such as sunflower, rapeseed or even hazelnut oil, posing health risks to individuals allergic to the substitute oils. This practice has implications for food safety, as the adulterated oil may contain other compounds that are potentially toxic or harmful.

Using stable isotope analysis, scientists can effectively trace the geographical origin of a food item, differentiate between organic and conventionally produced foods, and detect adulteration by identifying inconsistencies in the expected isotopic signatures.

Rapid screening approaches are another method used to detect fraud and verify the authenticity and provenance of food.

Using near infrared spectroscopy, scientists at the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture (Joint FAO/IAEA Centre) were able to distinguish between extra-virgin olive oil from Slovenia and other countries with 94 per cent sensitivity and 86 per cent specificity.

“Infrared spectroscopy and other techniques such as headspace gas chromatography–ion mobility spectroscopy can be used to analyse samples in the laboratory or directly in the field. They offer high sample throughput and low operational costs as they require little or no sample preparation, and there is no need for chemicals or specialized laboratory facilities,” says Christina Vlachou, Head of the Food Safety and Control Laboratory of the Joint FAO/IAEA Centre.

Honey fraud is similarly prevalent, with cheaper sweeteners such as high-fructose corn syrup being added to natural honey. Stable isotope analysis and rapid screening tools can help to detect honey adulteration, verify claims about floral or geographical origin, and differentiate authentic manuka honey — which commands a high price — from fake versions.

In the case of seafood, scams often take the form of mislabelling, whereby a cheaper species of fish or seafood is sold as a more expensive variety — a practice that not only deceives consumers but undermines conservation efforts aimed at preventing overfishing of endangered populations. Stable isotope analysis allows scientists to verify whether products are correctly labelled, and can even be used to distinguish between farmed and wild-caught fish.

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The IAEA supports food safety and quality globally and forges partnerships to fight food fraud under Atoms4Food, a new flagship initiative launched last year.