How to choose and prepare
It is much easier to judge the freshness of whole fish than fillets or steaks.
First you look at the eyes. If they are clear and plump that means it is fresh. If they are cloudy and starting to dry and collapse, no no no.... not fresh !
Then you can check the gills, they should look wet and lively red/orange/brown colour not dried or dark brown.
Then, third you can gently press the fish's flesh to see how well it springs back, if you leave a dent that doesn't recover at all, move along and buy a chicken instead.
As for smell, a very fresh whole fish doesn't stink even a little. It is not a good sign if the smell is strong, must be light smell mixed with the light parfum of the marine or fresh water.
How to gut, fillet and scale a fish
A filleting knife which is a long, thin and have a flexible blade as it allows you to
press down against the bones as you work and it will contours better than a rigid knife. You can use a different knife but it will be more difficult.
Just make sure you knife is shaaaaaarp because if not, it will tear the delicate fish flesh to shreds.
You can buy an inexpensive filleting knife, I bought mine for about $25 and it
is fine as I don't do filleting very often.
Fish bone tweezers (optional) as it can help pluck pin bones from the fillets.
Scissors/Kitchen shears , strong and sharp.
Fish scaler it is optional as you can scale the fish using the dull side of your knife, running it against the direction of the scale ( that's it... tail to head) but it is much better and faster with a fish scaler
It is useful to know how to break down a fish in case you are cast away on a deserted island and the only
food you can eat is the fish you have caught with your bare hands, or your friends invited you to fish from their beautiful boat and you actually succeeded and proudly came home with a Snapper or Herring (discard blow fish)
But on the civilized land, buying the fish whole means you can better see the quality of the animal, second you can keep the bones & heads and use them to make fish stock (I do freeze them in a special bag , mixed with my prawns heads or crabs shells until I do have enough to make a big quantity of fish stock that I'll freeze again in smaller jars) and third it is cheaper even after you accounted for the bone and head weight
When at the fishmonger, insist on being able to smell and examine your fish before buying it, all of them.
Remove fins, scales and guts.
Snipe off all the fins with kitchen shears.
Scale the fish from tail to head with a fish scaler or knife.
It can be messy, the scales fly absolutely everywhere !
Tricks: -1fill your sink with cold water and submerge the fish while scaling it-The scales will stay in the water.
-2 do it in a transparent plastic trash bag, the scales fly up and stick to the bag around the fish.
Double check for scales as I always find one or two which manage to slip by. There are a few spots where you're most likely to find stubborn scales, around the belly, dorsal area and near the head.
You can use your hand or the dull side of your knife to feel for remaining scales, very often you have to get in there with your fingers and pluck the off one by one.
Clean up as you go, making sure to wipe up any and all scales that litter the cutting board and fish. The cleaner you can keep your fish and your work area, the less you will have to worry about scales sneaking into your food later.
Guts : slice open the belly from tail up to the head and rip them all out then throw it away.
Slice behind the head
Position the fish with its back side nearest to you. Using your knife, slice down through the meaty section right behind where it meets the head. Make the cut angle in toward the head, since the meat extends under it a little and you don't want to lose any of it. If you cut too close to the head, the blade will run into bony obstructions ; too far away, though, and you will lose good meat.
Remove first fillet
Now, with your knife, cut along the back (dorsal side) of the fish, right above where the bones are, moving from the head to the tail. Continue making nice, even cuts as you go deeper and deeper into the fish, separating the fillet from the bones below. Try to exert an even pressure on the blade so that it presses flat against the bones as you cut; this will help ensure that you get as much meat off as possible. Be careful to keep your other hand away from the blade as you work: you'll have to move it around a bit, but placing it directly on top of the fish with your fingers flat is safest.
If you need to take a peek under as you go, you can gently lift the fillet; just be careful not to bend it back too much or you can tear the flesh. Once you're halfway through, the knife will ride over the spine itself, and you'll sometimes hear and feel little clicks as it slips from vertebrate to vertebrate, cutting through pin bones that radiate off the spine.
Then keep on working towards the belly with those same long, even strokes of the blade, sliding it right on top of the bones that run around the belly portion. The fillet gets pretty thin here so it's easy to accidentally cut through. Just take your time, go easy, and keep that blade pressed against the bones as you go.
Once you've gone all the way through, the fillet should come right off; if it's still attached somewhere, just use your knife to cut it free without damaging the meat.
Remove second fillet
Now it's time to turn the fish over and do the other side; once again, position it so that the back is nearest you.
Make another cut behind the head, angling toward the head as you go deeper to avoid losing good meat. Working from about the midway point, slice along the back of the fish towards the head, once again right above the bones.
Now turn your blade so that it's pointing towards the tail and slide it all the way through the fillet until it comes out the other side; make sure you press the knife against the bones as you do this. Riding right on top of the bones, slice towards the tail until the knife cuts the fillet free from the tail half.
Then turn the blade back toward the head and cut the fillet free, once again riding right on top of the bones with a gentle downward pressure, until you've gotten as far as the spine.Once past the spine, take your time and search for a good angle to free the fillet from the belly bones. It can seem a little awkward at first but you'll get it.
When you're done, you should have two good fillets, plus a head and bones that have very little meat left on them. Save the head and bones for fish stock or soup.
Trim the fillets and remove pin bones
The next step is to clean the fillets up and get them ready for cooking. Start by trimming the belly flaps off each one. The belly flaps aren't very tasty: they're thin, often have bones stuck to them, and sometimes a bitter flavor from the organs that they once contained. A nice, clean, even line is what you're looking for here.
Also trim off the very bottom of the fillets at the tail end for a cleaner line there. And lastly, I'll slice off any bones that managed to come off with the fillets (usually hugging the surface on the head side).
Then use your fingers to feel along the fillet where the spine was attached. You'll usually feel pin bones in the fillet, especially nearer the head end. Take your tweezers and very gently try to grab the top of each pin bone without digging into the flesh itself. Then pull each one free. It can help to use the fingers of your free hand to press down on the flesh around the bone as you lift it out, to prevent the flesh from tearing.
There's one little pin bone almost everyone misses, right near the skin on the head end. Get that one too.
Trick : Lay the fillet over an upturned bowl to make the pin bones protrude and easier to find :)
Now repeat this a few hundred more times….
Thank you for www.seriouseats.com for this inspiring and clear method.