Escolar, Lepidocybium flavobrunneum

The escolar (Lepidocybium flavobrunneum) is a species of fish found in tropical to temperate waters 650 to 2,900 feet in depth, around the world. It is also known as the snake mackerel, walu and sometime sold as butterfish or white tuna.

It has been mislabeled in restaurants and fish markets as white tuna. In studies from 2010 to 2013, it was found that 84 percent of over 114 samples of tuna were actually escolar. However, the studies were conducted with no quality control so the accuracy is in question.

The escolar has also been confused with, Atlantic cod, oilfish, rudderfish, blue cod, black cod, king tuna, grouper, orange roughy, sea bass, gemfish, Chilean sea bass and albacore tuna.

There is a health risk by consuming escolar. The escolar cannot naturally metabolize the wax esters giving it an oil content of 14 to 25 percent. This can cause stomach cramps to rapid loose bowel movements which could occur from 30 minutes to 36 hours after consuming. This condition is called steatorrhea. Two ways to avoid this is limit intake to six ounces or less and only consume meat that is closest to the tail.

The body color of the escolar is a dark brown that becomes darker with age until it is black. There are four to six small fins after the anal (bottom fin near the rear) and second dorsal (top fin).

The sale of escolar has been banned in Italy and Japan. In 1977, Japan considered the fish to be toxic. Hong Kong, in 2007 investigated the mislabeling of fish and recommended the escolar not be used in catering and labeling and identification of the fish must be done before sale. Also consumers must be informed of the health risk of escolar and related species.

The FDA from the United States, issued a bulletin in the early 1990s recommending against importing the species, but retracted their decision after determining the fish was nontoxic and nonlethal. Currently the FDA recommends the fish should not be marketed in interstate commerce.

The Canadian Food Inspection Agency didn’t ban the fish, instead issued a fact sheet advising of the potential effects if consumed and recommended to only eat small portions.

In 2010 a bill was deferred banning the catch, sale or possession of escolar.

Image Caption: Escolar (Lepidocybium flavobrunneum). Credit: Allen Shimada, NOAA NMFS OST/Wikipedia (public domain)