Here I have tried my best to show the novice the basic steps to fillet a flatfish.
Once again I have gone as slow as possible and also tried to keep my hands out of the way as well as keeping the action on screen and in focus. Unfortunately when taking the last fillet off the underside I have not mentioned in the commentary that the piece of flesh (white) left along the anal fin is the belly flap that covers the intestine mass and the gonads that go quite away along the length of a flatfish, that is why the point of the knife went in just at the end of the belly sac. I hope this helps.
General hints and tips that might also help;
Again a very sharp knife is required as flatfish skin, especially flounders skin is quite tough. Although the fish in the video was under 2lb, I would not bother normally filleting a flatfish under 2lb 8oz, it is not worth it. There is nothing to get hold of, and the flesh that runs along the dorsal and anal fins is so thin normally that it is difficult to remove, and the flesh on the underside is quite thin as well and only produces wafer thin fillets. Far better just gut and cook whole. There are exceptions to this, sometimes you do get nice plump smaller fish, which can be filleted.
If you do get a decent sized flatfish, it is also a good idea not only to cut across the tail and down the lateral line, but also along the edges of the dorsal and anal fin so when you take the flesh off the rib cage the fillet comes off neatly and should not need trimming. If, in the future, I get a decent sized flatfish I will endeavour to show you this, as well as another method of filleting flatfish. If you get a nice plump fish it is possible to remove both fillets at the same time. By cutting from the dorsal fin, cutting along the ribs, over the back bone/lateral line and down to the anal fin. Only point here is that when you have done this, you tend to cut the fillet in two anyway for cooking, so it is your choice.
Other points when making a video or filleting, take the phone off the hook, only had one interruption and shut the dog in the kitchen!
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