Authentication of a food product based on DNA analysis of an added natural biological tracer: testing the application to dry cured hams

Food authenticity is crucial for all value chains, including many meat products. Various methods have been developed to authenticate meat products based on the intrinsic DNA information of the animals from which the products originated. In this study, we propose an alternative method of authentication based on DNA analysis of a biological tracer added to the product. To demonstrate its effectiveness, we conducted a pilot study focused on dry-cured hams that were authenticated using genetically characterised wheat flours, obtained from different accessions. The study consisted of three main steps: first, we analysed 23 wheat accessions using random amplified polymorphic DNA assays and seven wheat microsatellites to assess the accession homogeneity/homozygosity and establish accession specific microsatellite fingerprinting; next, we tested, as a proof-of-concept, the feasibility of using genetically characterised wheat flour as natural tracer when mixed with lard (used to cover the skin-free part of the legs) and ink (used to label the legs), which are routinely applied in ham production; finally, we tested the possibility of authenticating hams by retrieving DNA information from the applied matrices (lard and ink mixed with flour) on the legs that were cured and ripened for 16 months. The DNA fingerprinting was consistent throughout all evaluation stages enabling the authentication of the marked hams. One advantage of this system is that the tracer (and its DNA profile) is known only to the the authentication system managers. This approach can be adapted to authenticate many other food products.