Advances to prevent food fraud in the consumption of virgin olive oil and pine nuts

Food fraud occurs when products that do not meet consumer expectations reach the market and, in extreme cases, this can lead to health problems. To combat this misleading and critical practice in the food sector, a team from the University of Barcelona has published new studies presenting technologies to verify the geographical origin of two food products: virgin olive oil — emblematic of the Mediterranean diet — and pine nuts, the most expensive nuts on the market.

Professors Stefania Vichi and Alba Tres lead the study that is part of the doctoral thesis conducted by researcher Berta Torres, from the UB’s Faculty of Pharmacy and Food Sciences, the Nutrition and Food Safety Research Institute (INSA) and the UB’s Torribera Food Campus.

How can the authenticity of virgin olive oil be guaranteed?

Knowing the country of origin of products such as olive oil significantly influences consumers’ purchasing decisions and affects the market price. The virgin olive oil supply chain is particularly vulnerable to fraud, and falsification of the declaration of origin is especially difficult to detect. This is because, despite European regulations on mandatory declaration of origin, there is still no official method to verify this information and this opens a critical gap in the food chain.

To address an issue that urgently requires effective solutions, a number of fast, cost-effective and efficient authentication techniques have been developed and presented to identify frauds entering the market. But, which method has the highest level of reliability? An article published in the journal Food Chemistry compares, for the first time, the two most promising methods between specific and non-specific techniques to authenticate the geographical origin of virgin olive oil: stable isotope analysis and sesquiterpene fingerprinting.

The study, carried out in collaboration between the UB, the Research and Innovation Centre of the Fondazione Edmund Mach (Italy) and the University of Perugia (Italy), highlights the great potential of sesquiterpene fingerprinting to verify the geographical authentication of virgin olive oil. “The results indicated that the sesquiterpene fingerprinting method outperformed isotopic methods in reliability in several aspects, such as classification accuracy, sensitivity and selectivity”, note the authors, members of the UB’s Department of Nutrition, Food Science and Gastronomy.

The study also identifies the need to increase the transferability of this biochemical technique to ensure its global application and thus more effectively combat counterfeiting in the food chain.

Determining the region of origin of the pine nuts
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In a second paper, also published in the journal Food Chemistry, the team adapts the above analytical strategy to make progress in an area where reliable verification methods are still lacking: ensuring the authenticity of the geographical and botanical origin of pine nuts for consumption.

“The traits and price of pine nuts vary according to the pine species and the region of origin. In this context, Mediterranean pine nuts get much higher prices than Asian pine nuts, which encourages fraudulent counterfeiting”, researchers explain.

The study, carried out in collaboration with the Institute of Agrifood Research and Technology (IRTA), indicates that monoterpene and sesquiterpene fingerprinting analysed with solid-phase microextraction and gas chromatography-mass spectrometry — combined with chemometrics — is a fast and highly efficient system.
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“With almost no sample preparation, the methodology reveals 100% accuracy in distinguishing between pine nuts originating in the country and those from abroad. In addition, it reaches 99% in the ability to differentiate stone pine (Pinus pinea) from different regions of Spain. This powerful and automatable tool represents a breakthrough in the fight against fraud and counterfeiting in the sector”, concludes the team.