Maple syrup, often called Canada's "liquid gold," has long been a target for fraudulent activities, such as the dilution or substitution with other syrups, due to its high demand.

Amid threats from the United States of increased tariffs and the imposition of a baseline tariff of 10 per cent on all imports that aren't compliant with the Canada-United States-Mexico Agreement, increased maple syrup fraud is a possibility.

Food fraud, or economically motivated adulteration, is the deliberate misrepresentation of food for economic gain. This can include the substitution, dilution, addition and/or the removal of ingredients. Mislabelling of products is another form of food fraud that can happen at any point in the supply chain, from farm to fork.

Read more: Sweet little lies: Maple syrup fraud undermines the authenticity of Canada's 'liquid gold'

Food fraud is a multi-billion-dollar industry and poses serious risks. It can harm consumer health, tarnish brand reputations and value, jeopardize the livelihood of legitimate producers and even hamper biodiversity and conservational efforts.

The threats of tariffs on Canadian goods by the U.S., which includes maple syrup and equipment used to make it, has raised concerns on both sides of the border about price increases and supply shortages.

Canada produces more than 70 per cent of the world's maple syrup and Quebec is the capital of this production. In 2024, the province exported around $450 million worth of maple syrup to the U.S.

Historically, food fraud has increased during harsh economic times, growing financial pressures, pandemics, climate incidents, wars, supply chain disruptions or any other event that destabilizes the balance between food supply and demand. These circumstances often increase food prices, creating an incentive for fraudsters to exploit the system.

From 2020 to 2024, the world faced significant supply chain disruptions due to the COVID-19 pandemic, regional wars and significant climate events. Unsurprisingly, food fraud cases have increased tenfold, according to recent estimations.

Threats of higher tariffs could further contribute to this problem by increasing the likelihood that fraudsters will substitute high-value foods for lower-value products.

Given what we have learned from past cases of food fraud, threats of increased tariffs causes uncertainty in the supply chain, increasing the risk of fraudulent maple syrups from entering the market.

To combat this threat, there is a need for rapid, real-time and cost-effective methods to test maple syrup for authenticity.

Since the 1980s, various methods and tools have been developed or used to detect maple syrup adulteration. However, food fraudsters continuously adapt to evade detection, making it progressively more difficult to test for maple syrup adulteration. The more complex the testing methods, the more difficult they are to circumvent.

Traditionally, maple syrup quality testing involves measuring the dissolved sugar content in syrup through a unit of measurement known as degrees Brix. One degree Brix is equivalent to one per cent sugar. However, applications may be limited if unknown or non-conventional adulterants are used.

As fraud techniques become more sophisticated, new approaches are needed to ensure the authenticity of maple syrup. Non-targeted food analytical methods, such as fluorescence spectroscopy, allow for the screening of a wide range of samples, creating a fingerprint of a sample. The fingerprints can be compared to a reference library of profiles, or multiple attributes specific to maple syrups, rather than just one.

A recent study by our research team at the University of Guelph's Corradini Lab explored how fluorescence fingerprints can be used to detect maple syrup adulteration.

Fluorescence fingerprinting works by examining how internal molecules in maple syrup glow when exposed to UV and visible light. These unique, glowing fingerprints allow for the detection of markers or features that may be indicative of maple syrup fraud.

Our study explored the adulteration of amber and dark maple syrups, with common maple syrup adulterants - namely beet, corn and rice syrups - at values ranging from one to 50 per cent.

We mapped unique and distinctive features in the fluorescence fingerprints, which were then used for differentiating pure from adulterated syrups. When exposed to UV and visible light, maple syrup features changed depending on the type - beet, corn or rice syrups - and amount of adulterant.

Using the markers of maple syrup identity, we were able to apply AI to analyze multiple fluorescent features simultaneously. This allowed for the identification of pure maple syrups from adulterants, with accuracy ranging from 75 to 99 per cent.

In fact, analyzing the fluorescence fingerprints of pure and adulterated syrups with the assistance of AI and machine learning techniques improved detection by up to 30 per cent, and identified adulterants at levels less than two per cent.

However, expanding the fluorescence fingerprint reference library can improve the accuracy and reliability of results. AI models often require very large and extensive databases. This will be crucial for understanding and accounting for how factors like the environment, geographic location and processing conditions may affect the maple syrup glow.

The use of AI to analyze fluorescent markers in maple syrup could allow for rapid and effective identification of suspicious fraudulent samples.

With the increased risk of food fraud due to threats of increased U.S. import tariffs on Canadian products, combining AI and maple syrup fingerprinting can detect maple syrup fraud. This will ensure that consumers receive safe, high-quality foods while protecting the identity of one of Canada's most iconic products.