Thursday, February 13, 2014

Cod fish

When I was living in UK, I love to eat cod fish and chips due to its delicious lean and firm dense white flaky meat. But when I returned here and ate steamed cod fish, I find that the texture of the meat is different, the cod fish here has finer, very much softer flesh, not firm at all.

Later I found out why. The cod used for fish and chips in UK are the Atlantic cod (Gadus morhua) or North sea cod (according to reports, several Atlantic cod stocks have collapsed but with efforts made by fishermen to conserve cod stocks there are now an“encouraging rise” in stocks) whereas the cod fish sold here are the Pacific cod (Gadus macrocephalus).

In chinese, cod fish is known as "鳕鱼" (鱈 sounds the same as 雪 which means snow 鱼 means fish). Recently after reading this blog post, I am made aware of a fish known as 龙鳕鱼 (dragon cod) that according to the post: "Dragon cod is supposed to have fat that the human body cannot digest" but eating in small amount should be all right but eating more will give the person diarrhea (Keriorrhea to be accurate).

So I wanted to find out exactly what fish this "dragon cod" is and a google search came up with two possibilities - The escolar (Lepidocybium flavobrunneum) or oilfish (Ruvettus pretiosus). Both are species of snake mackerels and the oil of both consists of wax esters, which cannot be digested like edible oils and when consumed in a large amount some people experience a laxative side effect.

Some restaurants and fish sellers purposely mislabel these fish as cod, butterfish, white tuna, and many other types of fish. According to wiki, there was a Hong Kong oilfish controversy in 2006/7 and several cases in Canada where people fell ill after eating mislabelled oilfish that was sold at Chinese supermarkets (also in 2007). After knowing this, I think I will just stick to eating salmon and tilapia because I won't be able to tell the difference between a real cod and a mislabelled fish.