Espresso
Dialling in espresso
Fix the dose, fix the yield, and change only the grind until the shot tastes right. Then write it down.
- Skill level
- Intermediate
- How long it takes
- Three to six shots for a new coffee
- Equipment needed
- Burr grinder, Espresso scale, Espresso basket
- Steps
- 7
Why it works this way
Dialling in has a reputation for being fiddly, and most of that comes from people changing several things at once. The procedure that works is boring and reliable: hold everything constant except one variable, move that variable in a known direction, and taste. Grind is the variable to move, because it has the largest effect and the finest control. Dose and yield are the constants, because holding a ratio is what makes the comparison meaningful. Time is not a target — it is a reading that tells you whether the grind moved.
What you need
Helpful, not essential
How to do it
Pick a dose your basket is designed for and keep it fixed.
Weigh it every time. A dose that drifts makes everything downstream unreadable.
Pick a target yield, commonly around twice the dose by weight, and stop the shot there.
Weight, not volume. Crema makes volume a poor proxy and it varies with how fresh the coffee is.
Pull a shot, note the time it took to reach the yield, and taste it.
Time is the diagnostic reading, not the goal. A shot can hit 28 seconds and taste bad.
Too sour, thin or fast: grind finer.
Finer coffee resists more, extraction takes longer, and more of the sweeter compounds come through.
Too bitter, harsh or slow: grind coarser.
Coarser coffee lets water through sooner, taking less of the harsh compounds that come out late.
Change one setting at a time and repeat until it tastes right.
If two changes are made at once, a better shot tells you nothing about which one helped.
Write down the coffee, the dose, the yield, the time and the grinder setting.
Grinder numbers are not comparable between coffees or between grinders, but they are comparable between yesterday and today.
How to tell it worked
A shot that is sweet rather than sharp, with no ashy or drying finish, and a texture that coats the mouth rather than feeling watery.
If it did not work
What you saw, what to change, and why the change works.
Sour and harsh at the same time
Change: Treat it as a distribution problem before touching the grind.
Simultaneous under- and over-extraction is the signature of channelling, not of a wrong grind setting.
The shot changes when nothing was changed
Change: Check dose consistency, grinder retention, and whether the coffee is only a few days off roast.
Very fresh coffee degasses rapidly and its behaviour moves day to day.
Grinding finer no longer slows the shot
Change: Check the basket type and whether the coffee is stale.
A pressurised basket sets flow mechanically, and very old coffee resists less at any setting.
Common mistakes
Chasing a shot time
Shots that hit the number and taste wrong.
Instead: Taste is the target. Time is a reading.
Adjusting grind and dose together
No information from the result.
Instead: One variable at a time, always.
Not purging after a grind change
The first shot after an adjustment contains coffee ground at the old setting.
Instead: Purge a small amount, or accept that the first shot is unreliable.
Diagnose a specific problem
The science behind it
- Extraction
How much of the coffee's flavour has actually dissolved into the water — too little tastes sour or thin, too much tastes bitter or harsh.
- Extraction yield
The percentage of the original ground coffee's dry weight that ended up dissolved in your cup.
- Flow rate
How fast water moves through (or is pushed through) the coffee bed.