"White Tuna?"

For many who have come across ‘white tuna’ as part of sashimi menu, the truth is there isn’t such a fish in the world! It is certainly not a Tuna; rather a nick name given to a fish commonly known as Escolar, Lepidocybium flavobrunneum.

What type of fish is Escolar?  Escolar is known in the west as snake mackerel or walu walu. It is a dark fast swimming fish which is found in tropical and temperate waters around the world. In the USA, they are found in the Gulf of Mexico. As these fish is not able to metabolize wax esters found in its diet, hence, Escolars have a very high oil content. In fact, it’s Chinese name is ‘油魚’ which literally mean Oil Fish. 

The fish has a whitish to yellow texture and has flavourful and  oil-rich taste. While it may be super tasty to many but unfortunately, it can also cause something called keriorrhea.  

Often this fish can be mislabeled as the Chilean Sea Bass and sold generically as ‘Cod’. It is banned in Japan and Italy.

Chilean Sea Bass vs Escolar

About 

What's the difference?

The Chilean Sea Bass flesh is white. The fish produces the fatty acid to protect the flesh against the icy cold water in the Antarctic. Hence it is natural. The skin has also a diamond shape arrangement. As the fatty acid is embedded in the cells of the meat, it does not have an oil smell. In terms of taste and quality, this is far superior, hence, price is always at a premium.

The Escolar has a yellowish tinge to the meat. As the wax esters are not metabolise by the fish, they are stored outside the cells of the meat. This gives it an oily feel and smell. The skin has a poker dot pattern. The price is much cheaper as compared to the Chilean Sea Bass, mainly due to it’s lower quality of the flesh and the ease of harvest. 

Smart Tip

How to buy a good Chilean Sea Bass?

colour of Flesh

White flesh with few blemishes. If it is yellowish, it may have been exposed to the environment for an extended period causing the fatty acid to oxidise and degeneration of the meat.

Keep frozen

If anyone says that it is fresh and chilled, likely it has been defrosted. When caught at sea, the fish is normally flash frozen at -40degC to keep the freshness and integrity of the meat. The cold chain should be kept till it's ready to be cooked. As there are oil in the meat, the best treatment is to keep it frozen. Ineffective technique in freezing can also cause the meat to be of inferior quality.

Vacuum pack

Using vacuum treatment will prevent interaction of oxygen on the flesh and keeping it from degrading even after prolonged storage in the freezer. Hence, if the fish is not vacuumed pack, be more cautious in buying them as the quality of the meat may not be of the expected standard.

Source

There are numerous companies that harvest these fishes. However, not all are MSC certified which is important to ensure we continue to maintain sustainable fish stocks around the Antarctica. We usually obtain our stocks from Australia and France which arguably have the best quality control amongst all other producing countries.