The sliver of raw fish sold as white tuna at Skipjack’s in Foxborough was actually escolar, an oily, cheaper species banned in Japan because it can make people sick. The Alaskan butterfish at celebrity chef Ming Tsai’s Blue Ginger in Wellesley was really sablefish, traditionally a staple at Jewish delicatessens, not upscale dining establishments.
At Chau Chow Seafood Restaurant in Dorchester, the $23 flounder fillet
turned out to be a Vietnamese catfish known as swai - nutritionally
inferior and often priced under $4 a pound.
The Globe collected fish from 134 restaurants, grocery stores, and
seafood markets from Leominster to Provincetown, and hired a laboratory
in Canada to conduct DNA testing on the samples. Analyses by the DNA lab
and other scientists showed that 87 of 183 were sold with the wrong
species name - 48 percent. ...
The Globe-sponsored DNA testing found 24 of the 26 red snapper samples
were in fact other, less prized species, including fish collected at
Minado restaurant in Natick, Teriyaki House in South Boston, and the now
closed Big Papi’s Grille in Framingham, owned in part by Red Sox
slugger David Ortiz.
All 23 white tuna samples tested as some other type of fish, usually
escolar, which is nicknamed the “ex-lax’’ fish by some in the industry
because of the digestion problems it can cause. ...
Frozen fish at grocery stores was far less frequently misidentified,
with some sellers - including Walmart, Trader Joe’s, and BJ’s Wholesale
Club - passing muster in all instances. At restaurants, mahi mahi and
swordfish were correctly labeled in all samples tested. ...
For example, nearly all of the sushi restaurants surveyed replaced
wild-caught red snapper with tilapia, a farm-raised species usually from
Asia that has a significantly higher concentration of the fatty acid
Omega 6, which some research suggests increases the risk of heart
--Jenn Abelson and Beth Daley, Boston Globe, on bait and switch