How to make fish stock

Why it is so fast

Fish bones are small, thin and soft, with far less dense connective tissue than a mammal or a bird. Everything worth extracting comes out within twenty to thirty minutes.

Beyond that, the bones themselves begin to break down and release compounds that are bitter and faintly metallic. The stock also becomes unpleasantly gluey.

This is the reverse of the usual stock intuition, and it is the mistake people who are used to chicken stock reliably make.

The method

Half an hour, start to finish. Cooling, storing and reheating a stock or broth safely is a food-safety matter rather than a question of taste, and the Food Standards Agency is the authority on it. Follow its guidance rather than a recipe timing.

1. Use bones and heads from white fish — sole, plaice, turbot, cod, haddock, whiting. Oily fish such as salmon, mackerel and herring make a strong, greasy stock that suits very little.
2. Remove the gills from any heads. They are bitter and they cloud the stock. Rinse the bones well to remove blood.
3. Sweat chopped onion, leek, celery and fennel in a little butter without letting them colour. A fish stock should stay pale.
4. Add the bones and sweat them for a couple of minutes.
5. Add a splash of white wine and let it bubble off, then cover with cold water.
6. Bring to a bare simmer and skim. Never let it boil.
7. Simmer for twenty to thirty minutes only, then strain immediately through a fine sieve without pressing.

Uses and variations

• Fish soup, chowder and bisque, which all depend on it.
• Risotto with seafood, where a fish stock makes an enormous difference.
• Poaching liquid for fish, sometimes reduced first.
• Reduced into a sauce with cream or butter for a fish dish.
• Paella and other rice dishes built on seafood.
• Shellfish stock, made from prawn shells and crab or lobster shells roasted first, which is a different and excellent thing.
• Freeze it in portions. It is quick to make and worth having.

Notes

Which fish

Lean white fish. Oily fish gives a strong, greasy stock suited to almost nothing.

Gills

Remove them. They are bitter and cloud the stock.

Time

Twenty to thirty minutes. This is the whole difference from other stocks.

Colour

Pale. Do not brown the vegetables or the bones.

Shellfish shells

Roast prawn, crab or lobster shells first for a deeper, sweeter stock. That one can simmer a little longer.

Which fish, and which never

The one place fish stock genuinely goes wrong is in the choice of bones, and it is not recoverable.

• Use flat white fish. Sole, plaice, turbot, brill, halibut. The classic and the best.
• Round white fish work well too — cod, haddock, whiting, hake, monkfish.
• Never oily fish. Mackerel, herring, salmon, sardines and tuna give a strong, greasy, unpleasant stock that nothing rescues.
• Prawn and crab shells make an excellent stock by the same method, and they want roasting first.
• Never the guts, gills or blood, all of which turn it bitter. Rinse the bones thoroughly first.
• Heads are excellent once the gills are removed, and they carry a great deal of gelatine.
• Ask the fishmonger. Bones are usually free and they will know what came in that morning.
• Salmon is the exception people try, and it is genuinely unpleasant. Make it once if you do not believe it.

Common questions