Wormy Fish

[Papasail]

I have been trying to learn everything I can with respect to life on a boat. I love to fish, and watch Youtube fishing shows in Florida. They talk about which species to stay away from, but relate that parasitic worms keep slowly getting worse. The research I’ve read is bearing this out as well, stating that it should come as no surprise, and they can be found in nearly every species, though some are worse than others.

To kill them, you can either blast freeze them down into negative temperatures, or cook them at high temperatures…

What are most folks doing?
What are (your) general practices?
(Caribbeans)

[rslifkin]

If you go for the freezing option, you've gotta freeze cold and for at least a few days. The standard for sushi is to freeze for a week at something like -4* F. There a second standard where you can freeze significantly colder (I think it's around -30) for a shorter time (but most of us don't have freezers that can get cold enough, especially on the boat).

[Wheelguns]

I think you are worried about nothing. I worked as a charter boat captain and mate off and on for over 30 years, and have only found worms in a very few species. I have found them in red grouper, but not very often. I have also found them in amberjack and black drum, but not in every fish. Cooking the fish thoroughly will kill them, although I usually just don’t keep these species. The worms are usually found in the larger specimens.

[GordMay]

Originally Posted by rslifkin

If you go for the freezing option, you've gotta freeze cold and for at least a few days. The standard for sushi is to freeze for a week at something like -4* F. There a second standard where you can freeze significantly colder (I think it's around -30) for a shorter time (but most of us don't have freezers that can get cold enough, especially on the boat).

Cook fish, for about 10 minutes per inch thickness, to an internal temperature of 63°C (145°F).
Fish is fully cooked when the colour of the flesh turns from translucent to opaque (becomes white), and flakes easily at the centre, and separates easily from the bone, when tested with a fork.
Freeze fish, until the centre of the fish is solidly frozen, to an internal temperature of -35°C (-31°F) for 15 hours, or to -20°C (-4°F) for at least 7 days.

[Overdue]

Worms and Parasites. In addition to worms, many are concerned with parasites from water/ certain foods (Montezuma's revenge), in parts of MX and maybe some places in the Caribbean. You can protect yourself with "Food Grade Diatomaceous Earth", very inexpensive, can be stored in a ziplock plastic bag, 1/2 gallon bag will last a long, long time. 1/2 tablespoon mixed with cranberry juice, for example, will eliminate from your digestive tract whatever you might have. Make sure you get the food grade, and be careful, it is ok to ingest, but do not inhale it. A few Youtube videos if interested in a detailed explanation.

[stormalong]

Having caught dozens or even a hundred fish at sea I have only encountered one with worms, I cut out that part of the meat and cooked the rest.

There is nothing as tasty as fresh Dorado sushi dipped in wasabi.

[SailingHarmonie]

It is a little more complicated that people suggest here.

MOST parasitic worms in SALTWATER fish are harmless to people. You could eat them raw without a problem, although they can be a little gross... The only "tropical" fish I have come across that routinely carries a significant visible parasite load in the meat is greater amberjack. They can have a LOT.

There are two fish parasites that I know of that can make humans unhappy. Pacific salmon can host a tapeworm (Diphyllobothrium nihonkaiense) that lives quite happily in the human gut.

Atlantic cod and herring host a "seal worm" that can cause illness (anisakiasis) in humans if ingested while alive. These can (rarely) even cause problems when cooked because they can trigger an allergic reaction in some people. With the HUGE rebound in the seal population in New England and the Canadian Maritimes, it is now very rare to find an adult cod without at least a dozen or more of these larval nematodes in the meat.

Other than cod, I have seen no evidence that fish parasites are more numerous, and I catch and clean a LOT of fish.

[MicHughV]

Interestingly, I first came across fish worms while diving for grouper in the B'mas. Not all the grouper species has them though. Seems to be isolated to the Nassau grouper species.

The worms are clearly visible once you have filleted the fish.
I simpy cut them out. Usually no more than two or three of them. Once out, you can't tell any difference. As above, the number of grouper I've speared are countless. Never had any issues.

The only other fish I've come across that had fish worms is Amberjack, usually found near the tail. Amberjack is not considered a good eating fish by most and is rarely seen on a menu.

Besides those two species, I have never come across worms in other fish and I've been diving and fishing for decades.

[chris mac]

My experience comes from a background as a chef, including acouple years at a seafood restaurant. As well as 4 years aboard now spearing and line fishing.
Many "bottom" fish will have worms in their flesh. Halibut is actually quite bad with it. Grouper, as mentioned by others, has them as well. They are mostly harmless to humans. I cut them out if I find them though, anyways.
When cooked, they usually turn the same white color as the fish. So most people have eaten them without knowing it.
It's more rare to find them in deep water fish, like Mahi or tuna.

[Marathon1150]

Parasitology classes taught at universities typically buy saltwater fish from a market to demonstrate the presence of round worms (mostly nematodes). As noted above, other fish can be infected with tapeworms. Neither are very good for people if they enter the "wrong" organ or the life stage of a tapeworm is in the wrong organism.

Best advice is noted in a previous post above: cook the fish or if you prefer raw fish, freeze it before eating it.

Tropical reef fish like the Parrotfish can also contain ciguatera, a toxin produced by one or more species of reef algae. This can make people quite sick and is best avoided by not eating reef fish where ciguatera has been previously found.

[Cheechako]

My experience is it's always bottom fish. Not pelagic species. Never seen a worm in those. Ling Cod is one of the worst for worms.

[wholybee]

It is worth it for many in this thread to do some research. While historically Pelagic fish have been considered safe, there has always been a small risk, and in recent years it has grown considerably. Tuna very well might have worms.

https://www.healthline.com/nutrition/raw-tuna#parasites
https://www.foodsafetynews.com/2020/...eafood-dishes/

[MicHughV]

When I'm not catching fish myself, I buy it from a seafood market. In all my years I have never come across any fish tainted with worms.
I can't say whether the seafood market checks for worms and removes them if found, but across the board, whatever fish you select, is worm free.

I've never eaten Parrotfish as they are reputed to contain ciquatera, nor have I eaten barracuda for the same reason above, but I've known many that have eaten both without ill affect. Despite that, I still refrain from eating them.

[flightlead404]

Originally Posted by Overdue

Worms and Parasites. In addition to worms, many are concerned with parasites from water/ certain foods (Montezuma's revenge), in parts of MX and maybe some places in the Caribbean. You can protect yourself with "Food Grade Diatomaceous Earth", very inexpensive, can be stored in a ziplock plastic bag, 1/2 gallon bag will last a long, long time. 1/2 tablespoon mixed with cranberry juice, for example, will eliminate from your digestive tract whatever you might have. Make sure you get the food grade, and be careful, it is ok to ingest, but do not inhale it. A few Youtube videos if interested in a detailed explanation.

This material, essentially dried ground up dirt from places like Nevada that used to be shallow inland seas, is also excellent at killing insects, absorbing oil spills, and interestingly companies like MacDonalds use it as a thickener in their milkshakes.

I don't think its used in toothpaste any more, but I'm sure its used in various polishes as its a decent cutting compound.

[sv_pelagia]

Originally Posted by flightlead404

This material, essentially dried ground up dirt from places like Nevada that used to be shallow inland seas, is also excellent at killing insects, absorbing oil spills, and interestingly companies like MacDonalds use it as a thickener in their milkshakes.



I don't think its used in toothpaste any more, but I'm sure its used in various polishes as its a decent cutting compound.

haha

But no science backing the use of "Food Grade Diatomaceous Earth" by humans to disinfect drinking water nor, alternatively, to treat human intestinal disorders from drinking water containing, for example, giardia or cryptosporidium....