SSR fingerprint reveals mislabeling in commercial processed tomato products.

The presence of inaccurate food identification is an increasing global concern. The occurrence of species substitution in the fish and meat sectors has been documented in numerous cases. In comparison, there is much less information on the incidence of food mislabeling in the plant sector, where variety substitution is the most frequent problem. Our aim was to reveal possible mislabeling of commercial tomato products by a means of molecular genetic analysis. We focused our study on the “San Marzano” because it is considered among the most important industrial tomato in the world and fetches a higher market price. Since 1996, an EU Protected Designation of Origin (PDO) scheme guarantees the authenticity and origin of the true “San Marzano” production. In this work, SSRs were tested on 20 tomato varieties, validated on foodstuff and then employed to establish the genetic identity of 25 commercial tins labeled as “San Marzano”. SSR fingerprint was able to reveal that cans contained fruits that do not have the genetic profile of the ‘San Marzano sel. 2’ or ‘Kiros’ varieties, the only ones allowed for the production of PDO labeled products. Our work proved the usefulness of DNA-based tools to guarantee the authenticity of premium plant varieties. Furthermore, it strongly prompted the introduction of DNA tests for the control and law enforcement in agro-food chain. Our work demonstrated that SSR fingerprint could be used to optimize business objectives and match consumers' demand of authentic plant-derived foodstuff.