Dialling In Espresso: Dose, Time and Yield

Why Espresso Is Unforgiving

Espresso is the least forgiving brew method. A two-second drift that would go unnoticed in filter coffee shows up clearly in the cup. The good news: there are fewer variables than people assume.

Three Numbers

Every shot is described by three figures:

• Dose: the coffee you put in the basket. 18 grams is a common starting point for a double.
• Yield: the liquid that ends up in the cup. The classic ratio is 1:2, so 36 grams out of an 18 gram dose.
• Time: from the moment the pump starts to the moment you stop it. Aim for 25–30 seconds.

Write these down before you adjust anything. Untracked experiments just repeat themselves.

Reading the Taste

If the shot tastes sour and thin, you have under-extracted. Grind finer; the time will stretch and the flavour will settle.

If it finishes bitter and drying, you have over-extracted. Grind coarser, or pull a slightly shorter yield.

Change one variable at a time. Adjust grind and dose together and you will never know which one helped.

About Tamping

Tamping pressure matters less than people think. What matters is a flat, even bed. Water escapes through the weakest point of a tilted puck — that is channelling, and it makes a shot sour and bitter at once.

Water and Temperature

Around 93 °C works for most coffees. Going to 94–95 °C brings out sweetness in lighter roasts; dropping to 90–91 °C keeps darker roasts from turning harsh.

A Practical Routine

1. Leave the grinder where you left it yesterday.
2. Measure the first shot and record dose, yield and time.
3. Taste it: finer if sour, coarser if bitter.
4. On the second shot, change only the grind.

By the third attempt you are usually there. Run the routine again whenever you open a new bag — every batch asks for its own setting.