Tracing hazelnuts geographical origin: Isotopic markers

Food fraud can have many implications. Ranging from ‘counterfeit’ parmesan cheese​ to contaminated pork​ – fraud is a constant presence within the food industry.

Hazelnuts are not immune. The commodity, despite not being deforestation-linked by the EUDR​, is coming under scrutiny​ due to its links to bonded labour and child labour amongst its farmers, many of whom are seasonal workers.

The level of food fraud in hazelnuts, largely consisting of misleading consumers on their geographical origin, is difficult to quantify, but its effect on the sector is profound. With a diverse origin, hazelnut prices vary, and food fraud particularly impacts local producers with a protected geographical origin (PDO or PGI). Furthermore, prevalent food fraud generates consumer distrust in the sector. Now a new study has developed a way to link hazelnuts to their origin.

Isotopic markers as tracers

The study has developed methods of tracking the origin of hazelnuts, using isotopic markers to do so. The composition of isotopes, which are forms of atom that have different weights but the same chemical structure, depend heavily on their geographical locations. Isotopes are affected by factors like the geology of the ground and the type of agricultural practices that are applied on the soil, and thus isotopes can be considered ‘markers’ of a certain environment.

However, ascertaining the level of insight sufficient to ascertain a geographical location is often, from a single isotopic marker, difficult.

One of the major difficulties is that in addition to factors influenced by the climate in the hazelnuts’ geographical origin, there are agricultural factors to contend with. Some fertilisers, for instance, can influence isotopic markers. Others do not provide this issue.