Few people will have forgotten about the pan-European horsemeat scandal that first came to light in January 2013. This discovery of horse DNA in several ready-meal products remains one of the biggest failings of the food industry in recent times, with many consumers across Europe, Scandinavia and Russia subsequently ceasing to purchase processed meat products and ready-to-eat meals containing meat, particularly frozen meals.
“Horsegate,” as it quickly came to be called, saw public confidence in most retail giants plummet, while salivating sections of the media set about digging for the next major food fraud. As the world’s most widely traded food commodity, seafood and the industry supplying it has long presented a considerable target for the latter. Fortunately, the supply chain has so far avoided controversy anywhere close to the level seen in the meat category three years ago. And yet it’s generally agreed that seafood fraud – particularly the selling of products with a misleading label, description or promise – is rife.
The new report “From ocean to plate: How DNA testing helps to ensure traceable, sustainable seafood,” published last week by the Marine Stewardship Council (MSC), points to recent global analysis that found on average 30 percent of seafood products are “misdescribed or mislabeled,” with figures as high as 43 percent in some species-specific investigations; this despite many of the major importing markets like the United States, Japan and the EU introducing new traceability regulations in recent years.
As the title of the NGO’s study suggests, DNA testing offers an accurate means of verifying the authenticity of seafood products, and it duly shares results from its most recent DNA testing program of MSC-labeled seafood sold in retail, which found that 99 percent of products were correctly identified. Overall, 256 of the 257 randomly selected items from 16 countries could be identified through the third-party DNA analysis. Of the 256, just one product was found to be mislabeled – a frozen fish fillet from a European retailer that was labeled as MSC-certified southern rock sole (Lepidopsetta polyxystra), while the DNA tests instead identified it as the northern rock sole species (Lepidopsetta bilineata). The mislabeling was therefore attributed to an accidental mix-up of two closely related species rather than a deliberate substitution.
While the results from MSC’s DNA analysis were very positive, less so were early results from the same organization’s latest survey of more than 16,000 seafood consumers across 21 countries, which finds that 55 percent doubt the seafood that they eat is what it claims to be on the packet. The study, conducted online in January and February this year, also states that 65 percent of those purchasing seafood want to know that their fish can be traced back to a known and trusted source, and that 63 percent look to eco-labels as a trusted source of information.
Of course, as MSC’s own testing has revealed, some mislabeling is unintentional and merely attributable to poor traceability, but there’s no question that much is motivated by profit, particularly when it comes to high value species. Aligned with this, the sheer global scale of seafood mislabeling provides ample cause for public concern.
So does DNA testing present the best way to establish greater consumer confidence? The answer is a resounding ‘maybe.’ The MSC concedes there are some limitations with its testing program. For instance, it didn’t include tuna products in the last round of testing saying it’s “notoriously difficult” to extract good quality DNA from canned tuna because the heating process used to cook and sterilize the fish during canning and the liquid the tuna is stored in (oil, brine, vinegar etc.) can denature the DNA and prevent the genetic barcodes of different species from being identified.
To address this particular problem, the MSC is working with Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO) to develop a test able to distinguish between all commercially important tuna species and their likely substitutes, and is more effective for canned products. This test will enter initial trials this year, and if successful it will be included in ongoing testing from 2017.
DNA testing is also less developed for shellfish and so the MSC is looking to expand the scope of its testing program to include other seafood products like shrimp and mussels. As such, it’s collaborating with researchers to explore the use of trace element fingerprinting (TEF) as a traceability tool. In addition, because of the frequency of mislabeling reports in restaurants, canteens and takeaways, it also plans to introduce a requirement for randomized testing in certified foodservice outlets.
While all are creditable actions, it should also be noted that MSC-certified seafood represents just shy of 10 percent of the global fisheries yield, or about 9 million metric tons (MT). This would imply there’s a huge onus on the markets and the supply chains therein to ensure traceability toolboxes are up to the task of ensuring the remaining 90 percent is authentic and that their consumers get exactly what they pay for.
