This unique tool used ‘trace elemental fingerprinting’ of shellfish soft tissues and shells to identify the harvest location of blue mussels and king scallops with a 100% success rate — including mussels reared from two sites located just 6km apart within the one bay.
The technique used not only correctly identified the site of harvest of scallops, but was also able to distinguish between harvesting events just six weeks apart, both with 100% success.
The Marine Institute provided scientific advice and input into the initial stages of the research project, as well as providing samples of mussels and scallops for the studies led by Dr Conor Graham of the GMIT Marine and Freshwater Research Centre in collaboration with Dr Liam Morrison of Earth and Ocean Sciences and the Ryan Institute, NUI Galway.
The research was also conducted in association with the Food Safety Authority of Ireland, European Food Safety Authority and University College Dublin.
Lead scientist Dr Graham said: “In recent years consumers have become more food-conscious, seeking traceability of produce, and while such tools exist for agriculture, until now no scientifically based system existed to trace both farmed and wild shellfish produce to their source.
“The aquaculture of shellfish such as mussels and oysters and the wild fisheries for scallops, razorfish and clams is a multi-million industry in Ireland supporting thousands of jobs in rural maritime communities around our coasts. This research aimed to create the world’s first bivalve shellfish scientifically based traceability tool for Irish produce to promote this ecologically sustainable food.”
Trace elemental fingerprinting is somewhat similar to genetic analyses, the Marine Institute explains, except that instead of identifying the variation in a number of genes to create a unique genetic identifier, it analyses how large numbers of trace elements contained naturally within the flesh and shells of shellfish vary uniquely according to growing sites.
Although the shells of mussels and scallops are composed primarily of calcium carbonate, other elements are incorporated into their shells at relatively low levels as they grow, which is determined by the bioavailable concentrations of these elements in the surrounding water column in which the shellfish live.
Details will also be presented by Dr Graham at the Marine Institute’s 11th Shellfish Safety Workshop next Tuesday 8 October at the Radisson Blu Hotel in Athlone. The event will include presentations from representatives from a variety of state agencies, academic and research institutions and the shellfish industry.
The Marine Institute is the national reference laboratory in Ireland for the monitoring of marine biotoxins and microbiological/viral contamination of bivalve shellfish, and provides this information to the competent authorities under legislative and statutory requirements.