Recently, tapeworms have been found in our wild salmon, and it’s causing quite a brouhaha. The wild salmon in the Pacific Northwest is one of the hallmarks that makes this region of the world unique and special, and as a chef, I have a double obligation to protect this amazing resource.
The “salmon” we get here in the UK is not salmon. It’s pink trout.
Real salmon are born in streams and lakes then migrate to the ocean. They generally eat only while living in saltwater and they breed only in fresh water. After a four-year lifespan in the ocean, they make a migration to their original birthplace(!), they spawn, then they die. As that they don’t eat during their migration, they eat before they make their start, which means that the longer the river they have to travel, the fatter and bigger they will be when they start off. Which is why Copper River salmon are so prized; that river is about 290 miles (or about the distance from Trafalgar Square to Dublin as the crow flies). Finally, wild salmon’s flesh is red/pink/rose from their diet in the wild.
The Atlantic “salmon” (or Scottish salmon as it’s known here in London) are part of the genus Salmonidae, I concede. But they have much more in common with lake and river trout than my mystical Pacific salmon. Atlantic pink trout don’t have a regular 4-year life cycle, and they don’t die after spawning. Worse, their flesh is grey. It’s only pink because of the food dye in the pellets that they’re fed while in their pens.
Worms in fish
But back to the issue at hand: Worms.
Tapeworms are a very common parasite found in fish. In fact, if you buy large fillets of halibut, you will almost always find at least one worm in every single fillet. They’re that common.
But while worms are common, they’re also stupid-easy to deal with. Simply freeze the fish for a couple days, then slowly defrost in your fridge before you cook it (or serve it as sushi). Better still would be to buy Frozen At Sea (FAS) fish, which is fish that’s frozen right there on the ocean trawler right after the fish has been gutted and cleaned. These boats have huge commercial freezers and can do a proper job freezing the salmon, much better and faster than your little consumer-quality freezer.
Fresh vs Frozen
Freezing has a really bad rap amongst consumers, and it’s undeserved. I would never buy “fresh” fish because within my industry, “fresh” equals “not frozen” which means that fish is likely to be just one short day from going bad. If the FAS fish is still frozen when I buy it, all the better, because now I can keep it and serve at my convenience.
To consumers (non-chefs), “fresh” means “is it still good to eat”? So if you buy into the romanticism of buying “fresh” fish, at least ask: “How many days ago did this particular “fresh” fish come out of the water?” If the seller can’t answer that easily and honestly, then don’t buy that fish. You might find it’s not so “fresh” after all.
There is one problem with freezing: For maximum quality, it can only be done once. We all know that water expands when frozen. Meat is mostly water, so those meat cells rupture when frozen and it feels mushy when defrosted. The more times you freeze/defrost, the more meat cells you’re rupturing, destroying the quality of the meat. And the slower the freezing process, the more damage you’re causing, which is why commercially frozen fish is likely to be the highest quality, as long as you don’t freeze it again when you get home.
Incidentally, this freezing policy also works for pork, which is why eating pink (medium-rare) pork is perfectly safe. Trichinosis can’t survive freezing, so if that chop has been frozen before you cook it, you can serve it with a nice tender pink center, instead of the dead grey curled piece of shoe leather we all had to do in the 1950’s (apparently).
Too long, didn’t read?
Buy whatever fish you want, just make sure that somewhere along the line it’s been thoroughly frozen. Then you’ll be ok. But if you’re still worried, make sure you cook it to an internal temperature of 145F.
Finally, if you must have something fish-related to get worried about and lose sleep over, it should be tuna and its mercury content. Tuna are at the top of the fish food chain (relatively speaking) so they accumulate all the mercury of all the fish it eats, and all the fish they ate, and all the fish they ate, so on and so forth. When the tuna gets to your kitchen, unlike tapeworms, there’s no cooking out the mercury.