Cooking time
4-8 hours (if using marrow bones only, up to 24 hours)
Ratio of ingredients for brown beef stock
50% Water
Enough to just cover the bones.
35% Bones – 1.5kg of bones will make 1 litre of unreduced stock
A combination of stock bones, marrow bones and meat trimmings (clean of fat and gristle) gives the stock a rich flavour and full body.
12% Mirepoix – Celery, Onion and Carrot (you can substitute leeks for onion)
Too much mirepoix in a stock can make it taste either too sweet or too bitter.
3% Tomato puree and aromatics – Parsley stalks, Bay leaf, Thyme, Peppercorns.
Add herbs and aromatics about an hour before the stock is finished cooking.
0.1% Spoonful of acid – Apple cider vinegar or Lemon juice.
Acid breaks down the collagen in bones and releases it into the stock.
Do not add salt
The objective of stock is to extract flavour from your ingredients and turn it into a liquid form. The next step is to reduce the stock and concentrate the flavour. But, if you've already added salt, you'll not just be concentrating the flavour – you'll be concentrating the salt too. So the time to add salt is when you use the stock in a dish.
Method
Blanch the bones
Put the bones in cold water and bring them to the boil. Boil for 15 minutes – skim off any scum – then remove the bones and discard the water.
If you're mixing marrow bones and stock bones together, soak the marrow bones in salted water for 25 hours, in the fridge. When done, take them out and rinse them well.
Roast the bones (optional)
Roast the bones in a hot oven for 30-60 minutes. You can add the vegetables too if you want.
For a good colour and flavour it's important they reach a surface temperature of between 140-165°C. (Maillard reaction).
Start with cold water
Put your blanched – or roasted – bones and other ingredients in a pot and add just enough water to cover them.
Add a table spoonful of acid but don't add salt.
Bring everything to the boil then immediately turn it down to a very gentle simmer.
Simmer, never boil
Boiling clouds stock. You're aiming for clear stock with plenty of gelatine in it – but no fat.
Boiling releases fat and other particles which then emulsify into a cloudy suspension, this makes it impossible to separate the fat later if you want to.
Skim frequently – never stir
Don't stir the stock while it's cooking because the impurities get trapped in the liquid. The scum is coagulated protein and can cloud stock – let it rise to the top and then skim it off.
Keep the water level up
Don’t try to reduce the stock, if the water level drops, top it up.
Simmer for 12-24 hours. It's done when the bones have started to crumble a bit, a signal that all the nutrients and proteins have been extracted.
Add the herbs and spices about an hour before it's finished.
When the stock's done, strain it carefully
As soon as it's finished cooking, strain the stock. Avoid excessive agitation to keep the stock from clouding.
Reduce – and concentrate – the stock (optional)
After you've finished straining and removing the fat you can concentrate the flavours by simmering down the stock.
You can reduce it by up to 75 percent to create a rich syrupy glace or glaze. Great for sauces and soups. And it takes up much less space in the freezer.
Re-cook the bones for more stock (optional)
After the stock's cooked and drained, add more water to the bones and a fresh mirepoix (onions, celery and carrots) and fresh aromatics. You'll get a second batch of stock. It won't be as punchy as the first one – but it'll still have flavour.
Food Safety
Always remember to rapidly cool your stock down. It shouldn't be left for more than 2 hours at room temperature. Any more than 2 hours and you'll need to re-pasteurise it.
Link pasteurisation
Beef stock bones
Beef marrow bones