Scientists are developing a new method to identify mislabeled, fraudulent seafood.
According to a report released by marine research organization Oceana in September 2016, seafood fraud is common in the United States. After analyzing more than 25,000 samples worldwide, the report found that one in five was mislabeled. Oceana also looked at more than 200 published studies from 55 countries, finding seafood fraud present in all but one investigation. Salmon, in particular, was subject to this kind of fraud, with cases of mislabeling found seven percent of the time.
But that could soon change.
Over the past six years, NOAA’s National Seafood Inspection Laboratory in Mississippi has been developing a method of rapid testing for seafood authenticity, as part of wider effort to crack down on seafood fraud. The lab is now hoping to expand these efforts to a broader range of species identification.
By employing a method called ‘electrophoresis and protein pattern matching’, NSIL has successfully produced a technique as a more rapid alternative to DNA testing for species identification. Though the technique has so far only been tested on a small number of species, the lab is now in the early stages of expanding those efforts to catalogue a wider range of protein patterns of commercially traded fish across the U.S.
“When we started this process, DNA testing was expensive and time-consuming,” said Dr. Jon Bell, lab director at the National Seafood Inspection Laboratory in Pascagoula, Mississippi. “This is a method we’ve been developing over half a dozen years or more here, to develop a rapid, inexpensive screening method.”
NSIL scientists distinguish proteins by size and charge. By analyzing thousands of samples, the lab has built a protein pattern matching software tool which can be used to determine the species of a fish.
So far, this database is focused on detecting commonly substituted species in whitefish. According to Bell, they’ve been using groupers, snappers and catfish as the species by which to test their methods. The next step, however, is to expand that database. According to Bell, they spent the summer collecting “samples to define the U.S. market.”
NSIL contracted John Kaneko of the Hawaii Seafood Council to acquire 100 seafood market species for the lab. He oversaw collection of finfish and shellfish species from across the country, including Alaska.
Quentin Fong, a seafood marketing specialist who works with Alaska Sea Grant at the Kodiak Seafood and Marine Science Center, was enlisted to collect Alaska fish species. Fong spent the summer working with processing company Alaska Pacific Seafoods to acquire five species of salmon. Samples of king, silver, sockeye, chum and pink, as well as Alaska pollock and Pacific cod were collected. These samples were then sent to NSIL in Mississippi.
Bell stressed that this project is in its nascent stages, though he’s hoping they can apply their method more broadly in the future.
“We did receive samples,” he said. “So we’re hoping that, over time, this method will be able to work for species of salmon as well.”
Bell said that the process uses a simple, off-the-shelf bio-analyser. He also explained that one of the project’s goals is to eventually have the protein pattern database online, which would drastically simplify the process of identifying fish species.
“If you’re a large buyer of fish, right now, you’d have to send samples off for DNA testing,” said Bell. “We’re hoping that this will be a usable tool.”
NSIL will be presenting their findings for feedback at the Seafood Expo North America, in Boston in March.