Articles - Boat fishing tips - how to fillet flat fish
A guide to filleting round fish
Des Westmore - Posted on 07 Jul 2010
AS with round fish, there are many methods and while there are similarities with round fish, the techniques for filleting flatfish do have subtleties of their own.
As with round fish and in my opinion any fish that your plan to eat, flatfish should be gutted as soon as possible.
In addition to the cutting or removing of the gills, a flatfish such as turbot or plaice also benefits from a cut across the ‘wrist’ of the tail. Doing this on the white side should ensure that the blood drains, assuming, the fish is kept the right way up in the fish box.
Keeping the gutted fish chilled for 24 hours prior to filleting is even more beneficial to flatfish than round fish as this period of chilled storage relaxes the flesh. As well as making it a better texture for eating, it makes the fish easier to fillet and as the flesh on a flatfish is often quite thin, anything that makes it easier to remove the fillet from the bone with minimum waste has to be a good thing.
Super Sharp Knife
Your knife cannot be too sharp. I plan to have a proper look at sharpening at the end of this series but for now, for those proficient with a stone, the DMT range of diamond dust stones is pretty hard to beat.
For those not so confident the Accusharp range of sharpeners is one of the best solutions that I have found. This type of sharpener has a Tungsten Carbide blade that is simply stroked along the knife blade gently. This can be done quickly and easily as often as necessary and is particularly convenient if filleting at sea. Just remember the age-old adage “You never cut yourself with a sharp knife” (yeah, right!) So, enough of this – let’s take a look at a flatfish.
Step 1
The flatfish in this case is a sole. Perhaps one of the harder fish to fillet, simply because of its size.
Step 2
The guts of the sole have been removed by making an incision through the white side of the fish into the stomach cavity. The incision was made at the front end of the cavity to keep as much of the flesh intact as possible. As with round fish, gutting is simply a case of removing everything inside after making the incision. Some people recommend removal of the fins with scissors before filleting. I don’t bother and simply trim any fin that may end up on the fillet afterwards.
Step 3
This is probably the main difference between flatfish and round fish. With round fish, you generally end up with two fillets. With flatfish the easiest, though certainly not the only, method of cleaning results in four fillets – two per side. The first step is, therefore, to divide the side of the fish. Cut along the length of the backbone from head to tail as shown, cutting down through the flesh until the blade hits bone. Try your best to cut directly above the backbone.
Step 4
This highlights another difference between round and flatfish. With round fish it is generally easier to fillet from head to tail. With flatfish, the problem with this method is that it makes it difficult to start the fillet. This is because the thickness of the head hinders maintaining a shallow angle on the knife blade for easy removal of the flesh. To highlight this, the first fillet is being removed the ‘wrong’ way.
Step 5
As can be seen, it still gets the job done, but the method doesn’t do you any favours!
Step 6
A far easier way is to start the fillet at the tail and work towards the head. A shallow angle can be maintained to remove the flesh from the bone. The completed fillet can then easily be cut from the body behind the head. The fillet is being supported in the picture for the camera – the knife is not cutting towards the fingers, which would be bad! The picture shows how important it is to keep the knife hard up against the ribs of the fish. The fillets are wide and thin on a flatfish and there is little room for error.
Step 7
Having removed the dark side fillets, your fish should look something like this.
Step 8
Removal of the white side fillets is simply a case of turning the fish over and repeating the process. Again, the fillet is divided with a cut along the backbone and the fillet removed from tail to head. White side fillets are generally thinner than the dark side. This can make things a little bit trickier so concentrate and take your time.
Step 9
The four fillets can now be cleaned up if any fin has been left on or if they look a bit ragged at the edge. The skin can be removed if required using the same method as for round fish. You may prefer a slightly less sharp knife for skinning. Many flatfish recipes however, recommend leaving the skin on as the fillets are often thin and leaving the skin on helps to hold the fillet together when cooked.
How to fillet rays - coming soon.
Read more great boat fishing related features by clicking here.
As with round fish and in my opinion any fish that your plan to eat, flatfish should be gutted as soon as possible.
In addition to the cutting or removing of the gills, a flatfish such as turbot or plaice also benefits from a cut across the ‘wrist’ of the tail. Doing this on the white side should ensure that the blood drains, assuming, the fish is kept the right way up in the fish box.
Keeping the gutted fish chilled for 24 hours prior to filleting is even more beneficial to flatfish than round fish as this period of chilled storage relaxes the flesh. As well as making it a better texture for eating, it makes the fish easier to fillet and as the flesh on a flatfish is often quite thin, anything that makes it easier to remove the fillet from the bone with minimum waste has to be a good thing.
Super Sharp Knife
Your knife cannot be too sharp. I plan to have a proper look at sharpening at the end of this series but for now, for those proficient with a stone, the DMT range of diamond dust stones is pretty hard to beat.
For those not so confident the Accusharp range of sharpeners is one of the best solutions that I have found. This type of sharpener has a Tungsten Carbide blade that is simply stroked along the knife blade gently. This can be done quickly and easily as often as necessary and is particularly convenient if filleting at sea. Just remember the age-old adage “You never cut yourself with a sharp knife” (yeah, right!) So, enough of this – let’s take a look at a flatfish.
How to fillet a flat fish - step by step guide
Step 1
The flatfish in this case is a sole. Perhaps one of the harder fish to fillet, simply because of its size.
Step 2
The guts of the sole have been removed by making an incision through the white side of the fish into the stomach cavity. The incision was made at the front end of the cavity to keep as much of the flesh intact as possible. As with round fish, gutting is simply a case of removing everything inside after making the incision. Some people recommend removal of the fins with scissors before filleting. I don’t bother and simply trim any fin that may end up on the fillet afterwards.
Step 3
This is probably the main difference between flatfish and round fish. With round fish, you generally end up with two fillets. With flatfish the easiest, though certainly not the only, method of cleaning results in four fillets – two per side. The first step is, therefore, to divide the side of the fish. Cut along the length of the backbone from head to tail as shown, cutting down through the flesh until the blade hits bone. Try your best to cut directly above the backbone.
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Step 4
This highlights another difference between round and flatfish. With round fish it is generally easier to fillet from head to tail. With flatfish, the problem with this method is that it makes it difficult to start the fillet. This is because the thickness of the head hinders maintaining a shallow angle on the knife blade for easy removal of the flesh. To highlight this, the first fillet is being removed the ‘wrong’ way.
Step 5
As can be seen, it still gets the job done, but the method doesn’t do you any favours!
Step 6
A far easier way is to start the fillet at the tail and work towards the head. A shallow angle can be maintained to remove the flesh from the bone. The completed fillet can then easily be cut from the body behind the head. The fillet is being supported in the picture for the camera – the knife is not cutting towards the fingers, which would be bad! The picture shows how important it is to keep the knife hard up against the ribs of the fish. The fillets are wide and thin on a flatfish and there is little room for error.
 |
 |
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Step 7
Having removed the dark side fillets, your fish should look something like this.
Step 8
Removal of the white side fillets is simply a case of turning the fish over and repeating the process. Again, the fillet is divided with a cut along the backbone and the fillet removed from tail to head. White side fillets are generally thinner than the dark side. This can make things a little bit trickier so concentrate and take your time.
Step 9
The four fillets can now be cleaned up if any fin has been left on or if they look a bit ragged at the edge. The skin can be removed if required using the same method as for round fish. You may prefer a slightly less sharp knife for skinning. Many flatfish recipes however, recommend leaving the skin on as the fillets are often thin and leaving the skin on helps to hold the fillet together when cooked.
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How to fillet rays - coming soon.
Read more great boat fishing related features by clicking here.
