Bone broth is a savory liquid made by simmering animal bones and connective tissue for hours, sometimes days, so the collagen, minerals, and amino acids dissolve into the water. Here is what that means, and what it does not.
At its simplest, bone broth is what you get when bones are simmered long and slow. The heat and time break down collagen into gelatin, which is why a good bone broth turns to jelly in the fridge and feels silky when warm.
Bone Broth vs. Stock vs. Broth
The three terms overlap, but the distinction is mostly about time and ingredients. Broth is usually meat and vegetables simmered for a short time, producing a thin, seasoned liquid. Stock uses bones and simmers longer for more body. Bone broth takes stock further still, simmering bones and joints long enough to pull out collagen and minerals, then is often sipped on its own rather than used only as a cooking base.
What Is Actually in Bone Broth
The exact makeup of bone broth varies by the bones used and how long it simmers, but most contain a recognizable set of components.
Collagen & gelatin
Collagen from bones and joints breaks down into gelatin, which gives bone broth its body and its set.
Amino acids
Glycine, proline, and glutamine are the amino acids most associated with bone broth.
Minerals
Small amounts of calcium, magnesium, and other minerals leach from the bones into the liquid.
How Bone Broth Is Made
Bones are often roasted first for flavor, then covered with water and a splash of vinegar, which helps draw minerals out. The pot is brought to a bare simmer and held there, with the surface skimmed occasionally, until the liquid is rich and the bones give up their collagen. Beef bone broth tends to need the longest simmer; fish the shortest.
To learn how to drink it, cook with it, and store it, see How to Use Bone Broth .
Common questions
Is bone broth the same as bouillon?
No. Bouillon is a concentrated, often heavily salted cube or paste meant to be diluted. Bone broth is a slow-simmered liquid valued for its collagen and body, and is usually much lower in sodium.
Does bone broth have to gel?
A firm gel is a sign of plenty of dissolved collagen, but a broth that stays liquid when cold is still perfectly good. Gelling depends on the ratio of joints and bones to water.
Is bone broth vegetarian?
No, by definition it is made from animal bones. A vegetable broth is the closest plant-based alternative, though it does not contain collagen.