Black stuff on cooked dungies

Of all the years of eating dungies, this happened for the first time this past year and then again recently and wanted to see if I was doing something wrong.

Last month, I steamed up the crabs with shell on, then put them in the fridge to eat next day.  When I cracked opened the shell, there was a lot of black fluid pouring out and noticed that there were black stuff around the meat area.  Tasted a piece and it was fine so I just ate around the black stuff.

I thought this happened because I had left the shell on.  So last week after cooking, I removed the shell then put them in the fridge and the same thing happened.  This time, the plate had bunch of black fluid pooled up and the meat tasted a bit off so I threw them out. 

Anyone know what causes this?

Not sure about the black stuff but the dark green stuff is good over rice

Were there black spots on the outside of the shells?

Sometimes if you don't cook them long enough they will turn a little black inside.

Try steaming hard for 18 minutes. If they have black spots when you catch them than throw them back.

-Eliot

Were they still alive when you cooked them? Or had they been dead for some time S.O.T.W.?

I am with Eliot.  I think those crabs were not cooked long enough.

I've had that happen with store-bought crabbies, which is why I stopped buying them.

from CDFW:
Question: I just bought two crabs and found one with black spots on the outside shell. I’ve seen these before and usually avoid them, but this time the seller sneaked it into my package. When I called him about it, he said he didn’t know what it is, but it doesn’t permeate the shell. This isn’t true—I’ve seen this stuff on the flesh at the joints. It looks like oil. Can you enlighten me? Besides being ugly, is it unsafe? (Mari V., Berkeley)

Answer: According to our senior fish pathologist Jim Moore, black spots on the shells of crustaceans are typically composed of melanin, which is the end product of a series of immunological reactions. This means the crab was likely responding to some shell damage that could be caused by physical trauma or a disease agent. In this case, the black spotted crab is probably safe if cooked correctly. However, if the discolored shellfish tissue has an unpleasant taste or texture, or looks or smells unusual, we always recommend not eating it.

There were no black spots on the shell and they were nice and lively when they went into the steamer pot.  Its just that I notice a pool of black liquid in the plate I put them on after cooking as well as black looking gunk forming around the edges of the meat.  But this all happens after several hours, shell on or without.

I usually steam them about 12-15 minutes per 2 crab and when I eat them after steaming, they seemed to be fully cooked.  Maybe I'll just try steaming them a little longer next time and check the results.   

Thanks for the input guys.

I've seen that liquid many times after refrigerating or freezing a cooked crab.  It's that yellow liquid that's inside the crab that turns black after it cools.  Sometimes it turns more dark green than black.  The longer you cool it the blacker it gets.  Still safe to eat though, I think cause I'm still here.  If you want to avoid that clean your crab right away after cooking by washing it in cold water and removing all the junk.  Then freeze or refrigerate it.

Rey

I've seen that liquid many times after refrigerating or freezing a cooked crab.  It's that yellow liquid that's inside the crab that turns black after it cools.  Sometimes it turns more dark green than black.  The longer you cool it the blacker it gets.  Still safe to eat though, I think cause I'm still here.  If you want to avoid that clean your crab right away after cooking by washing it in cold water and removing all the junk.  Then freeze or refrigerate it.

Rey

Are you SURE you're still here? Better pinch yourself a few times just to be sure. 

I've seen that liquid many times after refrigerating or freezing a cooked crab.  It's that yellow liquid that's inside the crab that turns black after it cools.  Sometimes it turns more dark green than black.  The longer you cool it the blacker it gets.  Still safe to eat though, I think cause I'm still here.  If you want to avoid that clean your crab right away after cooking by washing it in cold water and removing all the junk.  Then freeze or refrigerate it.

Rey

Ah...I'll try that next time. Thanks Rey.

from CDFW:
Question: I just bought two crabs and found one with black spots on the outside shell. I’ve seen these before and usually avoid them, but this time the seller sneaked it into my package. When I called him about it, he said he didn’t know what it is, but it doesn’t permeate the shell. This isn’t true—I’ve seen this stuff on the flesh at the joints. It looks like oil. Can you enlighten me? Besides being ugly, is it unsafe? (Mari V., Berkeley)

Answer: According to our senior fish pathologist Jim Moore, black spots on the shells of crustaceans are typically composed of melanin, which is the end product of a series of immunological reactions. This means the crab was likely responding to some shell damage that could be caused by physical trauma or a disease agent. In this case, the black spotted crab is probably safe if cooked correctly. However, if the discolored shellfish tissue has an unpleasant taste or texture, or looks or smells unusual, we always recommend not eating it.

Yeah that. Lately I've been seeing a lot more "dirty crab" like this coming from HMB.  I throw those back, unless it is isolated to something like a single leg.  But I've been seeing it on the body a lot lately, enough that I've been wondering if there is some sort of disease going around.

-Allen

I agree.  I have been seeing more crabs with the black spots at HMB this year.  Mostly on the legs and not as much on the actual shell though.

Those all get tossed back in the water.

I agree.  I have been seeing more crabs with the black spots at HMB this year.  Mostly on the legs and not as much on the actual shell though.

Those all get tossed back in the water.

For some of the leg wounds, it's obvious that the crabs are getting pinched by other crabs, perhaps as they sit in the pots before they are released back or escape.  But the body spots are not that and it's not just a spot or 2.  It's more prevalent, like a rash or something like that.

-Allen