April 25, 2017 — When you order ahi tuna tartare at a D.C. restaurant, can you be sure that’s what you’re getting? A new study from George Washington University found that some restaurants are serving similar, but not the exact, species of fish advertised on local menus.
A group of scientists led by Keith Crandall of the university’s Milken Institute School of Public Health tested 12 dishes at six seafood chains with locations in Washington to see if the fish or crustacean DNA matched what it was called on the menu. They found that one-third of the samples were incorrectly labeled.
But these weren’t cases in which tilapia was being sold as snapper. In most of the mislabeled samples, the DNA matched a closely related species and wasn’t an egregious substitution.
The study discovered “pretty mild substitutions,” Crandall said. “We didn’t see anything that looked like some kind of comprehensive fraud, to swap out an expensive piece of seafood for something much less expensive.”
Still, there were a few restaurants whose results might raise an eyebrow. At Bobby Van’s steakhouse, a dish advertised as a rock shrimp tempura was a DNA match with whiteleg shrimp, which is typically a much cheaper, farmed shrimp.
The testing was performed in 2015, and Bobby Van’s doesn’t have a rock shrimp tempura on the current menu. Jonathan Langle, the chain’s head of operations for Washington, said he doesn’t recall it being on the menu, and that it may have been a special.