Guides
Dialling in is how you find the grind and recipe that make a particular coffee taste good as espresso. Every bag is a little different, so even on a great machine your first few shots will probably come out sour or bitter. That’s normal. Most people pull a handful before one tastes right.
Go round this until you get a shot you like. It usually takes a few tries.
| If it tastes | It means | Change |
|---|---|---|
| Sour, sharp or thin, often a fast shot | Under-extracted. Not enough of the coffee dissolved into the shot | Grind a step or two finer and keep the dose and yield where they are. |
| Bitter, harsh or drying, often a slow shot | Over-extracted. Too much dissolved, harsh parts included | Grind a step coarser, again keeping the dose and yield the same. |
| Sour and bitter at once, or the shot spurts | Uneven extraction, usually from channelling | Look at your prep before you touch the grind. Break up clumps, tamp level and don’t overfill the basket. |
| Good, but too strong or heavy | The ratio is shorter than you like | Pull a bit more, say 40 g instead of 36 g, and leave the grind alone. |
| Good, but weak or watery | The ratio is longer than you like | Pull a bit less, say 32 g instead of 36 g, and leave the grind alone. |
Watch next: James Hoffmann on YouTube
James Hoffmann dials in a new coffee on camera. He pulls a shot, tastes it and talks through what he changes and why. Parts 2 and 3 pick up where this one leaves off.
Dose is the dry coffee you put in and yield is the espresso that comes out. We weigh both because a shot comes out topped with crema, a foam of gas and oils, and how much crema you get varies a lot between coffees. Two shots can look identical in the glass and still be several grams apart, so measuring by volume doesn’t tell you much.
Shot time tells you how quickly water is getting through the coffee, and that mostly depends on the grind. If you hit 36 g in 18 seconds you’re probably too coarse, and if it takes 45 seconds you’re probably too fine. But if a shot tastes great at 33 seconds, it’s a great shot. Don’t chase the number.
A 1:2 ratio means twice as much espresso comes out as the coffee you put in. Go shorter, around 1:1 to 1:1.5 (what cafés call a ristretto), and the shot gets thicker and more intense. Go longer, around 1:2.5 to 1:3, and it gets lighter in body and extracts more. That can turn a sour shot sweet, or push a good one over into bitter.
Light roasts are harder to extract. They usually want a finer grind, a longer ratio of about 1:2.5 to 1:3, and hotter water, around 93 to 96 °C. They often run past 30 seconds, which is fine as long as they taste good. Dark roasts are the opposite. They extract easily and turn bitter quickly, so use a shorter ratio, about 1:1.5 to 1:2, and cooler water, around 90 to 92 °C. If you can’t set the temperature on your machine, don’t worry too much about it. Grind and ratio do most of the work.
| Setting | Light | Dark |
|---|---|---|
| Grind | Finer | Coarser |
| Ratio | 1:2.5 to 1:3 | 1:1.5 to 1:2 |
| Water | 93 to 96 °C | 90 to 92 °C |
| Time | Often past 30 s | Goes bitter fast |
Coffee that’s just been roasted is full of carbon dioxide. It bubbles out during the shot and makes it foamy, uneven and hard to dial in. Most espresso roasts settle down 7 to 14 days after the roast date, and light roasts often need longer. Old beans have the opposite problem: less crema, faster shots and a flat taste, and you’ll find yourself grinding finer and finer to keep up.
When you’d happily drink the shot again, you’re done. Leave the settings alone for the rest of the bag, though you’ll probably need to nudge the grind finer as the beans age.
Since grind is the thing you’ll adjust most, the grinder matters more than most people expect. Our recommended builds pair a machine and grinder at each budget, or you can price out your own setup in the builder.
Photos: Arwen on Unsplash, Olha Ruskykh on Pexels.