When it first reaches you, the idea of seafood is one of cleanliness. Maybe it's the associated freshness of the ocean, or its reputation as a healthy food. However, underneath upscale presentations or coastal dreaming, there is a complex and opaque part of the global food system at work, and it's not always at the front of mind when shopping for fish and seafood.
The fish can't legally be called catfish in America because that title is reserved for domestic catfish, so it is usually sold as basa, swai, pangasius, and tra. It has been illegally substituted for at least 18 other fish worldwide, according to research by Oceana. Investigative researchers found the fish, which is actually called pangasius, being sold as much higher-value fish such as perch, grouper, sole, and halibut.