See Basa

Or how the Pangasianodon lost its teeth.

So I am making a stir-fry using a recipe from the excellent Chinese cookbook 'Ken Hom's Hot Wok.' It is a great book from which we have not had a bad meal after trying 30 of the recipes, and I now always use his 'one pint of water to 400 g of rice' method for steamed rice. The recipe in question this time was stir-fried fish with black bean sauce, which required procuring some white fish.

So off to the supermarket to get some. Cod fillets were available at £14/kg and something called basa at £10.50/kg (or 25% cheaper).

As stir-fry flavours are usually robust, cheaper is OK with me. But what sort of fish is a basa?

The source of the fish stated that it was Pangasianodon hypophthalmus; so that is the binomial name for a basa fish, yes?

No, in Vietnam P. hypophthalmus is called tra and basa is a different, although closely related, catfish species Pangasius bocourti. P. hypophthalmus is preferred by aquaculturists there as it is faster growing than P. bocourti. Outside of Vietnam basa is a marketing name and depending on where you are buying it around the globe "tra", "basafish", "catfish", "swai", "river cobbler", "cobbler", "basa", "pangasius", or "panga" might be used to describe one of two the main commercial species, P. bocourti or P. hypophthalmus, or more rarely any one of the other 30 species in the shark catfish family (Pangasiidae).

Pangasianodon hypophthalmus

P. hypophthalmus can grow to over 4ft in length and up to 100 lbs in weight and are omnivorous, so it is a pretty chunky fish, but actually similar in size to cod. Its generic name stems from the Bengali word pāṅgā (पांगा) meaning bowlegged or bow-form (presumably due to the shape of the type species for the related Pangasius genus, Pangasius pangasus, which originates from that region) and -odon, which derives from the Greek for teeth (or lack of in this case, as adult members of this genus lose their teeth during maturation); the specific name derives from the Greek hypo- meaning below and -ophthalmus meaning eyes, relating to the lower setting of the eyes in relation to other Pangasiidae species.

As with any farmed fish there are some hints of issues, but nothing major, and it is safe to assume that Tesco are fairly stringent about production quality. The Marine Conservation Society rates it as a 2-4, but mostly 3, on its' 5-point sustainability scale compared to cod, which is rated 1-5 but mostly 4-5. So it is a more sustainable option, apart from the food miles, and Vietnam produces major quantities (>1M tonnes/yr) of the fish.

Even though the recipe calls for cod, halibut or sea bass, which are Northern hemisphere marine white fish, they aren't commonly available in China and the consumption of farmed freshwater fish is actually higher than that of marine species. In the early 1990s when Ken Hom was preparing his book for publication P. hypophthalmus hadn't been introduced into the UK (basa arrived in 2007). So the recipe was probably anglicised and, ironically, using farmed freshwater fish from Vietnam is probably closer to what is actually eaten in China.

Either way, it was another good recipe from the cookbook.

PS The first title of this post is a hat tip to the incomparable Groucho Marx and his See Bass joke that he played on George Burns (see him recount it).