Beef limb, shin or ankle bones are the most suitable for making beef bone stock due to the rich tendons, cartilage and ligaments, and bone marrow close to the surface of the meat. Have your butcher cut the bone down the middle lengthwise.
Take a sharp pointed knife and cut the joint capsule.
You need to expose the ankle cartilage to release the most of the collagen as you can from the bone. If you buy a whole long bone, you will need to ask your butcher to chop it into smaller pieces of about 6-7 cm2. If you want to do it yourself, use a hacksaw blade with either 18 or 24 teeth.A commercial grade bone knife can only be used to chop the chicken bones and pork ribs, but is not safe for cutting beef leg bones.
Chicken bones add excellent flavor to the stock. The general rule is to use 0.5 kg chicken bones for every 2 kg other bones.
The hemoglobin and myoglobin in the bones and muscles are the main reason for the loss of clarity in beef broth and produce reddish brown broth. These two iron-rich proteins turn brown when heated. Soaking the bones in water for 4 hours removes some of the proteins.
Chicken bones should also be soaked.
Choose a soup pot bigger than 5 liters capacity, place the pre-soaked bones in the pot and add enough water to immerse the bones. Cover and heat on high until it comes to the boil.Remove the lid and continue cooking for 10 minutes.At this point, there will be quite a lot of foam on the surface of the water.
Remove the bones and rinse thoroughly, removing any dark pieces. Discard the water in the pot and wash it out.
Put the bones back into the clean pot and fill with water, completely submerging the bones to a depth of 2cm from the rim of the pot. Heat on high until the water temperature reaches to 90 degrees Celsius, then turn to low.
When cooking the stock, the water temperature should be maintained at about 90 degrees Celsius. If the temperature is too low, the collagen precipitation rate is too slow and does not produce enough flavor. If the temperature is too high and the stock boils too rapidly, the liquid will be muddy.
Use a thermometer to monitor the water temperature accurately.
It takes eight hours for collagen to precipitate fully from meat bones. If this is not convenient, you can divide this into two or three cooking times without affecting the result.
Filter the beef stock before use. This quite simple to do by lining a sieve with coffee filter paper. Filter the stock while it is still hot otherwise the collagen will form a greasy residue on the paper inhibiting the straining process.
Cooking at a lower temperature of 90 degrees Celsius means that there will not be as much fat released into the stock, which is the main source of the ‘mutton’ smell.