Kingfish With Mushy Flesh

[saltrix]

Over the years I have caught many kingfish and they are usually a good table fish.

I kill my fish and store in an ice slurry or at least covered in ice after bleeding and washing them, but still occasionally served up Kingfish fillets which had a soft mushy flesh and a terrible taste.

After much research I found this to be due to occasional infection of the fish with a parasite called Kudoa, probably Kudoa thyrsites, which infects the muscle tissue of the fish but is not apparent in the appearance of the fish. On death of the fish the parasite releases enzymes which change the flesh to mush.

The fish infected can be Kingfish, Tuna, Mahi Mahi, Tailor, and many others.

So do not think you have been careless with the fish by not getting enough ice on them, as it has nothing to do with that. It is a big problem in fish farms. Some research suggests about 1 in 10 kingfish are infected around Sydney, less further south and more further north.

To be sure the fish is not infected one way is to cook a small sample before freezing, as the infection is usually right through the flesh.

If you have a few fish freeze them seperately and mark them so you know which the crook lot is.

I would be interested to know how many other fishraiders have experianced the problem.

The other common parasite in the fish we catch is the marine tape worm in Jews and large trevally. Some fisherman I have shown them to did not know they were a tapeworm, but as it is not transferrable to humans if cooked I don't suppose ot matters

[framedtrash]

does it still happen if you eat the fish strait away

kings at my house never get frozen they are eaten within a day or 2 max

[mikeh191]

Thanks for the heads up Saltrix,I have noticed this before and thought I must have had to much water in the ice slurry.

Cheers Mike

[pauljm]

Yeah this has come up before.... i have only ever had 1 kingy that had soft flesh and this fish hardly put up a fight.... i was surprised when it got to the boat that it was actually a king.... have u noticed this with your sick fish or have they been the usual arm stretchers that they are? Thanks for the well researched post! Paul

[Piss'n'Broke]

Hmmmm cheers for that. Never had this problem and we eat kingfish all year round but will keep a eye out. Hate mushy fish!!!!!!!!!!!!!!!!!!!

Dan

[finin]

Also caused by varying temps the fish are caught in, especially from the north. I think the parasite or worm breeds more in warmer waters. Interesting spin off cray fishers have trouble with occys as they release a toxin into the shell which turns to mush so the occy can feed on it without damaging the shell, the cray remains in perfect condition, except no meat in it!

Edited April 22, 2010 by finin

[martymonsta]

Hi guys,

I have heard of the flesh turning mushy in the past but haven't experienced it myself.

As I enjoy Sashimi'd kingfish, does anyone what would happen if you ate the infected kingy raw? Or has anyone eaten part of a kingy raw, cooked the rest and discovered it turned mushy? Any side effects?

Cheers

Marty

[saltrix]

does it still happen if you eat the fish strait away

kings at my house never get frozen they are eaten within a day or 2 max

Yes, as soon as the fish dies it goes mushy, maybe you have never had one infected.

[prawn*]

yeah i have had this before and thought it was because i left my fish in the live bait tank full of water not ice.. then i did research and found out it must of had the prarasite even though i ate it it was very fishy smell to it and tasted average, after effects were sitn on toilet with tapass

[alasdair]

I use a lot of fish at work and have had this problem with kingfish, and a couple of mahi mahi over the years. I use both wild and farmed kingfish and from my experience the wild ones are more often infected, but this might just be from stricter quality controls on the farmed fish stopping them getting as far as me.

As for eating it raw I never have, it just doesn't look right.

alasdair

[Jiggy]

As finin said this is caused by warm water temps, as far as I know cold water kills the parasite that causes it. Kings from the north coast and Queensland are often afflicted with this problem. It's not that common in Sydney but it does happen, when it does there isn't anything you can do about it.

Cheers

Jiggy

[monch]

Thanks for the info Saltrix, but i have a few questions for you.

Once the fish is dead and the parasites release the toxin, does the flesh very quickly go mushy? Are there any visible signs on the flesh of the dead fish?

Is there any harm in eating the mushy fish raw? Totally cooked? cooked but still rare?

Thanks in advance for the clarification.

Monch