We almost never read news about parasites being found in fish. But don't let that fool you. They are there, much more often than you think. Hundreds of different kinds. In fact, I have just walked back indoors after chatting with one of my gourmand neighbors. The conversation started with the most recent burglary on our street, and ended on parasites in fish (a symbolic connection?). He told me about an experience he had a few days ago.
What happened was this: he had bought a whole halibut fish from Whole Foods Market for a dinner party. As he was in the kitchen with one of the guests, about to put the fish in the oven, the guest noticed a pinkish worm in the fish. What to do? The other guests were waiting. Should they just go ahead, cook and serve the fish and keep quiet about the worms, or go out for pizza? In the end, the guest who spied the parasite made a good suggestion. They called Whole Foods, which was still open and rushed down to exchange the fish for wild salmon. The manager believed their story, and said, yes, it does happen from time to time. Not that unusual at all.
What they found was probably a Cod worm ( the most recent scientific name is Phocanema decipiens) - a common "round worm" in fish. It is found in several kinds of fish such as halibut, haddock, flounder, sole and even red snapper. The larger fish are more likely to carry it. This parasite may sometimes look pinkish, creamy white or brown, and is about 4cm long.
But isn't fish inspected, especially those sold at upper-end ("healthy") stores such as Whole Foods? Yes, it is, and a process called "candling" is also used which is supposed to help the inspectors see any worm-type parasites. But no inspection is ever 100% effective. Candling is also less likely to work well with whole fish where filets are thick and the skin is on - as in the case of my neighbor's halibut.
If you happen to come across such parasites in your fresh fish, you have several options. One, you can cook the fish well, and eat it, parasites and all. They will be killed and harmless. Most of us would not have the stomach for this approach, or want to serve it to guests. The next option is to put on a pair of disposable gloves, take a sharp knife or tweezers, grit your teeth and carefully remove and discard any wormy creatures in the fish. You can then cook the fish and eat it. The third option is the garbage - hopefully getting a replacement fish from the store. Most stores would willingly comply, as Whole Foods did in this case.
The Safe Food Handbook discusses parasites in fish in more detail, and gives you the specifics on how to be safe.
To your good health,
TSF
