I've heard some say that fish only smells offensive if it's old. But my experience suggests that some fish, like salmon, are simply "fishier" and that the smell can put some people off. Is that right? If so, is there a simple explanation for the smell, or does it vary according to species? And which fish smell the least and most fishy?
Certain people who are "super smellers" who have a heightened sensitivity to smells. Assuming you aren't one of them: fish smells "fishy" when it's starts to age. If you can find a reputable fish monger, that would help.
That said, if you're sure you have fresh fish, and some fish just simply smell more, you can cut down on the smell, by a quick rinse and a marinade with an lemon juice.
As for why fish smell fishy... it has to do with amines contained in the fish. Amines get released as bacteria work to release them. Salmon, Tuna, others... are higher in amines, while fresh white fish, tend to be lower. You'd have to do a bit more research to find out more specific species...
Sure, some fish are smellier than others. The fishy smell arises from the production of various amines in the dead flesh. If you let your fish sit out on a warm counter for a day, it will get quite reeky. Here's a nice little explanation of the reaction between these stinky amines and lemon juice: Why fish is served with lemon juice.
I've never had salmon that had a fishy smell. I think it may be time to find a new fish monger or start buying a different brand if you buy frozen.
I imagine that oily fish (like bluefish) would have a stronger fishy smell and taste. It's very much not to my liking so I stick to 'white meat' fish like fluke, flounder, black fish, ling, sole, Nile perch, tilapia, etc.
Having said that, I also LOVE tuna steaks and salmon. It's just a small fortune here so I don't buy it often.
I have never had mackerel that didn't smell. And I've had it all kinds of ways, from all kinds of restaurants. Raw-cured in saba battera, canned in brine, grilled, baked, pan-fried, even in ceviche (marinated in lime juice)... doesn't matter. Mackerel has a REALLY pungent fish smell to me. It's the strongest-smelling of all the edible fishes by far. It's in a league of its own. I don't mind it to eat, but make sure not to get any on your skin, clothes or furniture.
Fish should never, ever smell! When it comes out of the water, whether fresh, sea or ocean fish never has an odor. The only way to prevent this is to buy from someone you know in a fish market. Sometimes they'll try and preserve shell fish by packing it in salt, so be careful not to add any before you taste it 'cause the salt taste will never leave the fish once it is packed that way.
Part time commercial fisherman and fishmonger most my life. Whoever started the fish shouldnt smell like fish is full of crap. The eyes the smell everything it all depends on how it is stored. I will tell you straight up as delivering fresh fish to stores nobody knows wtf there talking about. For example, if you take 100 pounds fresh sardines just off loaded from the boat and put them in a cooler with ice. In a matter of hours the eyes will be glazed, they won't look fresh. If you put them in cooler with fresh water and ice, in a matter of minutes the gills will be bleached looking. I would never eat fish that doesn't smell like fish, or the ocean. Some fish natural smell, for example halibut, lingcod. If there isn't a distinct fish and ocean smell to it I wont eat it. If the fish you buy doesnt smell like fish I would seriously start asking question.
I think the best thing to do is to not buy it until you are ready to eat it that day. Because when you buy it, its already as fresh as it will ever get in your hands short of catching and cleaning it yourself. But, most sea food should never have a fishy odor. It should always smell fresh and neutral clean. If that makes sense?
Salmon starts to deteriorate as soon as dead. Why you gill them as soon as you bring then into the boat. Put on ice. Tuna is a oil fish. I think the pink has a stronger smell. Fish caught on seaweed can have a stronger smell. Over those caught on the reef. But fish should not have a strong smell. Or be soft to the touch. Fish spoils fast. If buying fish look at the eyes they should be clear. Look at the gills they should be pink. If not do not buy the fish it has been out to long. Then they start to smell.
In my experience the mucus covering the body of bony fish can have a fishy smell even fresh from the water. I've caught tench that definitely had a fishy smell to them while they were still alive. And, in addition to that the mucus deteriorates very quickly, enhancing the odor.
as a side note: For some fish, including the tench and the carp there are recipes in Germany called Blaukochen (cooking blue) where the whole fish with the mucus intact is prepared in water with vinegar. That results in the mucus turning blue.
In the shop the mucus is normally washed off and thus should not be the reason for the smell.