“Frenchified” kiwis , actually grown in Italy. “ Honey laundering ” in which the true origin of the sweet stuff is masked for financial gain. Mexican-grown greenhouse tomatoes labelled and sold as Canadian, earning the offending parties a $1.5 million fine and three-year period of probation.
Such false claims of geographical origin constitute food fraud and come at a price far beyond fines, should the perpetrators be caught out. Food fraud impinges on the rights of the consumer, who is stripped of the ability to make informed decisions about the food they buy; and costs the global food industry an estimated $10 to $15 billion per year.
According to the Consumer Brands Association , fraud affects roughly 10 per cent of all commercially sold foods. The most commonly targeted products include dry spices, fish, fruit juices, honey, olive oil and organic items, the Canadian Food Inspection Agency says.
As with other types of food fraud , misrepresented country-of-origin information is difficult to identify. It often requires sophisticated investigative methods to uncover. Now, botanists at the University of Basel have developed a new cost-effective way to detect falsified plant products by building on a well-used technique: stable isotope analysis.
Based on the maxim “you are what you eat,” according to Nature Education Knowledge , stable isotope analysis has a wide range of applications. The isotopic signature — a ratio of chemical elements imprinted on materials, ranging from strawberry flesh to human bones — reflects what the organism has eaten and the particularities of food webs.
As a result, this signature can tell investigators where the life form has been and how it has responded to environmental changes.
Archaeologists use stable isotope analysis to decode past human diets and migration patterns. In law enforcement, it can help officials identify travel behaviour as well as the source of confiscated drugs. Some of the uses in food forensics include pinpointing the geographical origin of fruits and evaluating the purity of vanilla extract, according to the Arrell Food Institute at the University of Guelph.
Food fraud affects roughly 10 per cent of all commercially sold foods
Typically, when food forensics officials have a concern — say “Swiss-grown” strawberries (the botanists’ test case) suspected of being grown in Spain, where they can be produced at a much lower cost — the ensuing investigation would require the collection of physical samples from across Switzerland and Spain, explains Prof. Ansgar Kahmen , who led the research project, which was published in the journal Scientific Reports .
In order to validate the origin of the strawberries, a private forensic laboratory would then analyze the isotope composition of these reference samples and compare them to the signature of the suspect sample in order to determine which region was a match.
“The problem with this method is that you need to collect these reference samples. So you always need to go to the region under suspicion, or you need to send a certified collector there to collect these samples, and then they need to be shipped to the lab and you need to analyze (them),” says Kahmen.
This takes both time and money. By adapting the stable isotope method to use simulations instead, the botanists have bypassed the need to travel the world collecting reference samples. “(Our model) makes the process of origin identification faster and cheaper,” he adds.
In environmental plant biology — as in archaeology, conservation, food forensics and law enforcement — stable isotope analysis is a crucial method.
Because stable isotopes (those that “ do not decay into other elements “) record environmental and physiological variation, Kahmen and his team interpret them in order to learn how plants respond to changes in their surroundings — such as drought or rising temperatures — over time.
Though food fraud isn’t their primary area of interest, they saw the potential to adapt plant physiological isotope models and apply their understanding of how these signals are being generated. “In this case, we turned it around a little bit, and we looked at the potential of plants to record environmental signals across space,” says Kahmen.
- Think you’re buying snapper? Not so fast. New report finds nearly half of seafood samples mislabelled
- Do you actually know what’s for dinner tonight? We are all victims of food fraud
- Avofraudo: ‘Vast majority’ of avocado oil is either rancid or adulterated, study finds
Based on their models, which were driven by a dataset of environmental variables such as temperature and humidity collected across Europe over 11 years, they were able to map the isotopes of different elements and see how they vary by location.
Using their approach, it’s still necessary to measure the isotopic signature for the suspicious product. But by simulating the isotope patterns in plants across space, the researchers have eliminated the need to physically collect reference samples from the regions in question. They can now compare the suspect sample to the values their model generates to see if it supports or contradicts the country-of-origin claims.
“The big advantage of our method here is that it’s not only faster and cheaper, but you can actually simulate the theoretical isotope signals for regions that would otherwise be very, very difficult to get to,” says Kahmen. “With our method, we don’t have to go there. We can essentially simulate what the values there would be and then can compare a product to these values.”
While conventional stable isotope analysis is used to verify the geographic origin of meat products, such as Welsh lamb or beef , and track the migration of monarch butterflies (as in a study led by Environment Canada research scientist Keith A. Hobson ), non-plant organisms are beyond the scope of their model, Kahmen says. But with “minor adjustments,” it could be used to verify the origin of all plant products, including timber.
Illegally extracted timber is a multi-million dollar industry taking an economic, environmental and social toll. Extrapolating their model to wood, Kahmen says, is a potential next step.
“Illegal logging is a big environmental issue that I’m interested in. And so I think we could actually translate some of our basic science that we are doing into something that is applied in a similar way. We could offer a tool to law enforcement agencies or the WWF to try to constrain these illegal timber cuts; I think that would be a useful contribution to society.”