How to cook a fish to make its bone as soft as those in sardines?

If you can go with picking out big bones from fish before cooking/eating then there is this Chinese (as far as I know) method to soften smaller bones - like smaller bones in a Carp's back.

I've tried this method with roasting stuffed carps in the oven. The carps were rather big - 2-3 kg and spent like an hour and a half in the oven. I suppose this approach won't work with frying or boiling. Haven't tried it, though.

Before cooking the fish, cut its skin in several places (not very deep just to make sure the skin is cut). Then rub it with salt, soak in wine, and let it rest for about 15 minutes. After an hour and a half in the oven smaller back bones should be soft enough to go down unnoticed.

I have cooked salmon and all of the bones were soft enough to be edible. My method:

1. Put butter or oil on the cooking surface of the cooking dish or pot.
2. Lay the washed fish on the oiled surface.
3. Slice an onion and lay the slices on and around the fish.
4. Put on salt, pepper and a dash of powdered garlic.
5. Cover the cooking dish/pot and put in an oven at 200 degrees F.
6. After three hours, the fish and onions are well cooked. And the bones are as soft as those in a can of sardines.

1. Raw Sardines do not have soft bones. If they did they wont have a strong skeleton.
2. All canned fish that have bones in them have soft bones be it large fish or small fish because they are cooked. You will know this because bone in canned salmon has soft bones
3. Its not about chemicals. As organic canned fish with bones have soft bones. It is because once inside the can the cans are heated to kill any germs, and at the same time cooks the fish like it is in a pressure cooker.
4. You can cook fish in many ways to make its bones soft and edible. You can cut fish into slices with your favorite spices and use a pressure cooker and cook for 1 hour.
5. You can also cook it like you would cook pot roast overnight. 8 hours is enough. Use whole fish if you do so.

The spices you put are your choice. I personally like yogurt, chili, lime, cumin and little oil on mine. But you can use anything. Its not the chemicals or spices that make it soft but the cooking method.

cook the whole fish with pressure cooker for 30+ minutes depending on the size of the fish to soften the bones. Here is the article about the popular Indonesian Milkfish dish cooked with high pressure cooker. As we know, milk fish is known for being much bonier than other fish :)

http://presto-milkfish.blogspot.com/

Here is the recipe to try :)

http://lelakimemasak1.blogspot.com/2011/07/high-pressure-cooked-smoked-milkfish.html

The USDA released a paper on the effects of cooking on 'fish bones softening', and you can find it if you search online...they tested pressures of 15, 20 and 25 psi (which gave them temperatures of 220 to 270 degrees water temp under pressure)...and found that even tuna and rockfish had 'gelatinous bones' at the highest temp-pressures.

The only way to cook fish to 'soft bones' (gelatinous) consistency, and not destroy nutritional or flavor values, is to do so with a GOOD pressure cooker capable of 20-psi or more, and cook times from 30-to 120 minutes, based on your own personal tastes.

One time I made a mistake making fish stock. I put it on and fell asleep thinking it would be a short nap. Some hours later I woke to find the stock simmering. All the bones and heads were GONE. This is not even a hard boil!

I believe everyone who says fish bones can soften with pressure cooking. Think: When has a fish ever had to live in boiling water? Never. The bones never have to survive this. If Darwin is correct, you need only bones that are good for water that is not boiling :-)