Espresso Brew Guide

Great espresso is all about getting a few variables working together. Your coffee, grind size, dose, yield and extraction time all affect what ends up in the cup.

For The One, this is where we recommend starting:

Dose: 20g
Yield: 40g
Extraction: Around 28 seconds

Think of these numbers as a starting point rather than a strict rule. Every grinder and espresso machine behaves a little differently, so some adjustment is normal.

Grind Size

For espresso, you’ll need a fine grind. It should feel finer than table salt, but shouldn’t be so fine that it becomes powdery or clumps excessively.

More important than what the grind looks like is how it affects the flow of water through the coffee.

Grinding finer slows the extraction down.

A finer grind creates more resistance, making it harder for water to pass through the coffee bed.

Grinding coarser speeds the extraction up.

A coarser grind creates less resistance, allowing water to move through more easily.

This makes your grinder the main tool you’ll use when dialling in your espresso.

Dialling In

Start by weighing 20g of ground coffee into your portafilter.

Distribute the coffee evenly, tamp level and start your extraction. Place your cup on a scale and stop the shot once you’ve reached 40g of espresso.

Then look at how long it took.

If your shot runs too fast

If you’re reaching 40g in something like 18–22 seconds, your grind is probably too coarse.

The water is passing through the coffee too easily, which can leave the espresso tasting thin, sharp, sour or underdeveloped.

Adjust your grinder finer and try again.

If your shot runs too slow

If it takes 35–40+ seconds to reach 40g, or the espresso is barely dripping from the portafilter, your grind is probably too fine.

This can result in an espresso that tastes bitter, dry, harsh or overly heavy.

Adjust your grinder coarser and try again.

If you’re around 28 seconds

You’re in a good starting range.

Taste the espresso before making any further changes. A shot at 26 seconds might taste better than one at exactly 28 seconds, so don’t chase the number for the sake of it.

Make Small Grind Adjustments

When dialling in, make small adjustments to your grinder.

A small change in grind size can make a surprisingly large difference to extraction time, particularly with espresso.

Change one thing at a time. Keep your dose at 20g and your yield at 40g while adjusting the grind. This makes it much easier to understand what each adjustment is doing.

After changing your grind setting, you may also need to purge a small amount of coffee from the grinder. Some grinders retain coffee from the previous setting, which can make the first shot after an adjustment misleading.

Dose

Your dose is the amount of dry coffee you put into the portafilter.

We’re starting with 20g, but your ideal dose will also depend on the size of your filter basket. If your basket is designed for a smaller dose, don’t force 20g into it simply to follow the recipe.

Whatever dose you choose, weighing it consistently will make dialling in much easier.

Yield

Yield is the weight of liquid espresso in your cup.

With 20g in and 40g out, we’re using a 1:2 brew ratio.

That simply means we’re producing approximately twice the weight of espresso as the dry coffee we started with.

Using a scale is much more reliable than judging your shot by volume. Crema can make two shots of the same weight look very different in the cup.

Extraction Time

We’re aiming for approximately 28 seconds, measured from when you start the extraction.

Time is useful because it tells us how quickly water is moving through the coffee, but it shouldn’t be treated as the ultimate measure of a good espresso.

If your espresso tastes great at 26 or 30 seconds, there’s no reason to change it just to hit 28.

Taste comes first.

Tamping

Once you’ve dosed and distributed your coffee, tamp it firmly and level.

You don’t need to obsess over applying an exact amount of pressure. What’s more important is creating a flat, even coffee bed and being consistent from shot to shot.

An uneven tamp can encourage water to find an easier path through one part of the coffee bed. This is known as channeling and can lead to an uneven extraction.

Fresh Coffee Changes

Coffee doesn’t behave exactly the same way every day.

As roasted coffee ages, it gradually releases carbon dioxide and its behaviour during extraction changes. Temperature and humidity can also affect how your grinder and coffee behave.

That’s why a grind setting that worked perfectly last week may need a small adjustment today.

If your shots suddenly start running faster or slower, don’t assume something is wrong with your machine. A small grind adjustment may be all that’s needed.

The Starting Recipe

For The One, keep it simple:

20g coffee in
40g espresso out
Around 28 seconds

If it’s running fast, grind finer.

If it’s running slow, grind coarser.

Once you’re in the right range, taste it and make small adjustments from there.

The numbers get you close. Your taste tells you when you’ve got it right.