Kristin Struck, food and beverage director at Not Your Average Joe’s, said she was surprised by the DNA results. She said the company, which has 14 Massachusetts restaurants, would not deliberately place a threatened species on the menu, and had changed seafood suppliers before the chain learned of the Globe’s DNA test.
“It is just sad,’’ said Jennifer Jacquet, a post-doctoral researcher at the University of British Columbia Fisheries Centre who has written about seafood fraud. “Even if you are doing all you can to avoid a fish species like bluefin, you are still not protected from eating it.’’