Regarding the functioning of this technique, Dr. Pavel Solovyev, an NMR research technologist at the Edmund Mach Foundation (TN), explains that “magnetic resonance (of hydrogen in this case) involves exposing the sample to a very strong magnetic field and recording the response (resonance signals). Food products are usually mixtures of compounds, so it’s possible to understand their composition and even determine the concentration of individual components in the sample, such as sugars, amino acids, and other important substances”.

As for the variety of food matrices, Solovyev notes that virtually any food matrix containing compounds with carbon-hydrogen bonds can be analyzed, with the sole essential requirement being that the sample is in a liquid state, either initially or after extraction: “for example, wines, vegetable oils, and animal fats are analyzed directly, while cheeses, fruits, vegetables, and various solid products must first undergo extraction before analysis.'

Some foods, such as honey, allow for particularly simple sample preparation: just add water to obtain an extract. In the case of liquid foods, like milk, juices, or wines, preparation is even simpler, requiring only the filtration of solids. For solid foods such as fish, fruits, vegetables, pasta, and rice, the process begins with grinding the food into powder. Water or other solvents are then added, and the solid particles are filtered out.

After analyzing an original sample, conventional food or food suspected of fraud is examined for comparison to detect unique molecules across different treatments (organic vs. conventional) or to identify any intentionally added molecules.

When asked about the advantages of this technique, Solovyev highlights 

Its exceptional speed (usually requiring less than 30 minutes per sample), high reproducibility, and the ability to perform quantification along with pattern analysis in the same spectrum. Furthermore, being non-destructive, the sample can still be analyzed with other methods after NMR analysis.

By analyzing the characteristics of wines already classified as authentic, we can identify molecules that help us recognize fraudulent products. For example, some products may contain higher concentrations of sugars that do not come from the natural sugar in grapes.

The same applies to monitoring geographical fraud: wines from specific regions in Italy (or other countries) exhibit a set of typical and unique molecules from that region, which allows us to distinguish them at the molecular level from wines that come from a different, falsely claimed origin.

Food fraud also affects olive oil, of course. As highlighted by the Guardian, the first quarter of 2024 saw a record number of cases of olive oil adulteration in the European Union. In this case, the fatty acids of different types of oil frequently marketed (such as sunflower, soybean, and rapeseed oils) are analyzed. Then, 100% olive oil is used to check whether different oils have been blended together. In the case of olive oil, a common fraudulent practice is to add food-grade acidic substances to give the oil the typical acidity of authentic olive oil.

For functional foods that claim to include ingredients with properties promoting bodily well-being (such as bread or cookies with flax, chia, and sesame seeds), it is possible to verify their authenticity by first analyzing the functional ingredients (the seeds) and then analyzing the final product to identify unique molecules derived from the ingredients, thus confirming their authenticity. A study conducted by KBV Research indicates an annual growth rate of 8.3% for these products in the EU during the forecast period (2021-2027).

Consumers' increasing focus on health and the quality of the food they purchase has led to an increase in the availability of functional and organic products. A study by KBV Research predicts an annual growth rate of 8.3% for these products in the EU market between 2021 and 2027. However, for functional foods such as bread and cookies enriched with flax, chia, and sesame seeds, verifying their authenticity is crucial. This can be done through the analysis of the functional ingredients and subsequent verification of the finished product, or by searching for specific molecules that confirm the actual presence of the declared ingredients.

Similarly, organic products, such as vegetables grown using sustainable methods, require advanced techniques to certify their origin and authenticity. Nuclear magnetic resonance, for example, can detect different concentrations of specific compounds related to fertilizers and treatments used in the soil, providing an effective method for distinguishing truly organic products from those that are not.