Researchers led by Cranfield University have developed new ways to detect adulteration of sugar syrup in honey, paving the way for rapid and accurate testing to spot counterfeit products.
There is growing consumer demand for honey, with £89.8 million worth of honey imported into Britain by 2023. But because it is a high-quality product, it is vulnerable to fraud because syrups are added to dilute the pure honey – a report from the European Commission. The Commission found in 2023 that 46% of 147 honey samples tested were likely adulterated with cheap plant syrups.
Because the characteristics of honey vary due to nectar sources, harvest season and geography, detecting adulterated products can be very difficult and complex. Authentication methods are expensive and time-consuming, and there is a growing need for reliable testing and the adoption of new rules to combat fraud.
Now scientists from Cranfield University have successfully tested two new methods to quickly and accurately authenticate British honey.
Detect fake honey without opening the jar
A research project led by Dr Maria Anastasiadi, lecturer in bioinformatics at Cranfield University, with the Food Standards Agency and the UK Science and Technology Facilities Council (STFC), used a specialist light analysis technique to detect fake honey without opening the jar.
Samples of British honey fortified with rice and sugar beet syrups were tested using the non-invasive Spatial Offset Raman Spectroscopy (SORS) method – originally developed at STFC’s Central Laser Facility (CLF) – which is more commonly used in pharmaceutical and safety diagnostics. This proved to be very accurate in detecting sugar syrups in the honey. SORS quickly identified the ‘fingerprint’ of each ingredient in the product, and the scientists combined this technique with machine learning to successfully detect and identify sugar syrups from different plant sources.
The analytical method is portable and easy to implement, making it an ideal screening tool for testing honey throughout the supply chain.
Dr. Anastasiadi noted: “Honey is expensive and in high demand – and can be targeted by fraudsters, leaving genuine suppliers out of pocket and undermining consumer confidence. This method is an effective, quick tool to identify suspicious honey samples to identify, allowing the industry to protect consumers and verify supply chains.”
The paper Application of spatial offset Raman spectroscopy (SORS) and machine learning for the detection of sugar syrup adulteration in British honey was published in Foods 2024, full. 13.
DNA traces in honey are used to distinguish real from fake
In a second study, DNA barcoding was used, in collaboration with the Food Standards Agency and the Institute for Global Food Security at Queen’s University Belfast, to detect rice and glucose syrup spiked in British honey samples.
Scientists used 17 honey samples collected from bee farmers in the United Kingdom, representing different seasons and floral nectar sources, and purchased four samples of British honey from supermarkets and online retailers. The samples were then enriched with corn and rice syrups produced in a number of countries.
DNA barcoding – a method already used in food authentication to identify plant species in products – was effective in breaking down the composition of each sample, to successfully detect syrups even at the 1% adulteration level .
“Until now, DNA methods have not been widely used to investigate the authenticity of honey,” said Dr. Anastasiadi. “But our research shows that this is a sensitive, reliable and robust way to detect adulteration and confirm the origin of the syrups added to honey.
“The wide variation in honey composition makes it extremely difficult to verify authenticity, so having this consistent technique in the testing arsenal could take the sting out of honey fraud.”
Sophie Dodd, who is completing her PhD on the subject of honey authentication at Cranfield University, added: “It is essential to have samples of known origin and purity to validate the methods, so we would like to express our thanks to the Bee Farmers Association who we work closely with in our projects.”
The two methods developed can work together to increase the chance of detecting exogenous sugar adulteration in honey.
