What does it mean to reduce a sauce?
Reduction, in one line
To reduce a sauce means to simmer it so water evaporates, leaving a thicker liquid with a more concentrated flavor.
Why it works
As a liquid simmers, water leaves as steam but flavor molecules, sugars, and dissolved solids stay behind. The sauce gets thicker and stronger in taste. Gelatin and starch add body, too. Salt does not evaporate, so salt a sauce lightly before reducing or you may end up with a sauce that is too salty.
How to do it
Common mistakes
- Salting heavily before reducing, which makes the final sauce too salty.
- Boiling hard, which can break emulsions and scorch the bottom.
- Using a deep narrow pot, which slows evaporation a lot.
Questions about reduction
How long does it take to reduce a sauce?
It depends on the pan and heat, but halving a cup of liquid usually takes 5 to 10 minutes at a simmer. A wide pan is faster.
How do you know when a sauce is reduced enough?
It should coat the back of a spoon and leave a clear line when you drag a finger through it. This is called nappe.
Can you fix a sauce that reduced too much?
Yes. Whisk in a splash of water or stock until it loosens. Taste and adjust the seasoning.
Chicken Stock
Red Wine
Balsamic Vinegar
