Learn — Brew Guides
How to Pull Espresso at Home
9 bars of pressure. 25 seconds. The most sensitive brew method — and the most rewarding.
The Parameters
Espresso is a high-pressure extraction method. A pump forces water through a compressed puck of finely ground coffee at 9 bars of pressure — roughly nine times atmospheric pressure — in 25–28 seconds. That speed and pressure extracts a concentrated, emulsified liquid with a layer of crema on top. Every other brew method uses gravity or manual force. Espresso is the only one that uses a pump.
This concentrated extraction is what makes espresso the foundation of milk-based drinks — a flat white, latte, or cappuccino requires a shot strong enough to cut through and flavour a substantial volume of steamed milk. Brewed coffee at any other ratio is simply too dilute to hold up.
Crema
The reddish-brown foam on top. An emulsion of coffee oils and CO₂ formed under pressure — only possible at 9 bar. Crema indicates a fresh bean and correct extraction pressure. It dissipates within a few minutes; a flat, pale surface means old coffee or under-extraction.
Body
The middle layer — the primary liquid of the shot. Where sweetness, acidity, and fruit notes live. A correctly extracted body is thick, smooth, and slightly viscous. Thin and watery means under-extraction; harsh and medicinal means over-extraction.
Heart
The darkest, most concentrated part at the base. The last liquid to extract — carries the deep bittersweet character. In a well-pulled shot the heart integrates into the whole rather than dominating. In an over-extracted shot it is where harshness lives.
Brew Ratio
1:2 — What It Means and Why It Matters
The brew ratio is the single most important number in espresso. It is the weight of dry coffee going into the portafilter divided by the weight of liquid espresso coming out, expressed as a ratio. At 1:2, 18g of coffee produces 36g of liquid espresso. Adjust the ratio and you change the concentration, the sweetness, the bitterness, and how the shot works in a milk drink.
Ristretto
1:1 to 1:1.5 · 18g in, 18–27g out
Short, concentrated, syrupy. Stops extraction early — intensely sweet and aromatic with less bitterness than a standard shot. Common in traditional Italian espresso. Requires very consistent puck prep.
Short · Intense · SyrupyNormale — Standard
1:2 · 18g in, 36g out
The specialty coffee standard. Balanced sweetness, acidity, and body. Works as a standalone shot or as the base for milk drinks. The safe starting point when dialling in any new coffee. Simple Coffee's recommended starting ratio for both Espresso products.
Simple Coffee Standard · BalancedLungo
1:2.5 to 1:3 · 18g in, 45–54g out
Longer and more dilute — a bigger cup with lower concentration. Extended extraction adds bitterness at the end; quality lungo shots require precise grind control. More common in Europe. Not ideal for milk drinks — too dilute.
Long · Lighter · More bitterStop the shot by yield weight — not by time. Start the timer when the first drops fall. Stop the pump when the scale reads your target yield (36g for an 18g dose). Check the time afterward to assess your grind. If 36g arrived in 18 seconds, grind finer. If it took 45 seconds, grind coarser. Time is diagnostic; yield is the target.
Puck Preparation
The Four Steps Before Any Water Flows
Espresso punishes poor puck preparation immediately and specifically. Channeling — where water finds a crack or gap in the puck and flows through unevenly rather than distributing across the full coffee bed — is the most common source of bad shots, and it happens before the machine is ever switched on. Four preparation steps prevent it.
Dose Accurately
Weigh 18g directly into the basket. Consistent dose = consistent puck depth = consistent resistance. A varying dose means the puck height changes between shots, which changes flow rate and shot time unpredictably.
Why: Dose drives puck densityDistribute Evenly
Coffee grinds clump due to static and moisture. Tap the portafilter gently or use a needle (WDT tool) to break up clumps and level the bed before tamping. High spots and clumps become dense areas water bypasses — channeling starts here.
Why: Clumps = uneven density = channelingTamp Level
Press the tamper straight down until the coffee stops compressing. Keep the tamper perfectly level — a 1mm height difference across the puck is enough to channel. Firm and consistent matters far more than achieving a specific pressure number.
Why: Tilted tamp = slanted puck = side channelingPreheat the Group Head
Run a blank water flush through the group head before locking in the portafilter. This purges stale water that has been sitting in the boiler at the wrong temperature, and brings the metal group head up to brewing temperature. Cold metal chills your first pour.
Why: Cold metal drops extraction temperatureStep by Step
The Complete Pull
Flush and preheat
Run about 30ml of water through the group head with no portafilter locked in. This purges the old water sitting in the boiler and group head — which has been sitting at temperature and can be stale or slightly too hot. It also brings the group head metal to the correct temperature. Preheat your cup by filling it with hot water while you prepare the puck.
Grind, dose, and distribute
Grind 18g of coffee to fine — ground cinnamon texture. Grind directly into the portafilter basket. Distribute the grounds evenly across the basket before tamping. Tap the portafilter handle on the bench gently to settle, or use a needle to stir and level. No high spots, no hollow corners.
18g dose · Fine grind · Even bed before tampingTamp firm and level
Place the portafilter on a flat surface. Press the tamper straight down with firm, even pressure until the coffee stops compressing. Use your elbow, not your wrist — your elbow produces a more consistent vertical press. The tamper should be perfectly parallel to the basket rim. Do not twist the tamper at the end; this can break the seal at the edge of the puck.
Level is more important than pressure amountLock in, tare scale, start shot
Empty the preheat water from your cup. Lock the portafilter into the group head and immediately start the shot — do not let it sit, as heat from the group head begins to burn the coffee puck within about 30 seconds. Place the cup on a scale and tare to zero. Start your timer when the first drops fall.
Stop at 36g yield — check the time
Watch the scale. Stop the pump when it reads 36g — this is your 1:2 yield from an 18g dose. Note the time: it should read between 25 and 28 seconds from first drop. If it finished faster than 25 seconds, grind finer next shot. If it ran past 30 seconds, grind coarser. Time is feedback about grind; yield is what you stop by.
Stop at 36g · Time should be 25–28s · Adjust grind if notTaste and record
Taste the shot immediately — espresso changes quickly as the crema degrades. Note what you taste. Sour and thin means under-extracted: grind finer. Harsh and bitter means over-extracted: grind coarser. Balanced, sweet, and complete means you are dialled in. Write down your grind setting. Humidity changes daily and affects grind — you may need to re-dial after rain or very hot weather.
Dialling In
What the Shot Is Telling You
Espresso is direct about what went wrong. Every bad shot gives you a diagnosis — the taste, the time, and the visual all point to the same adjustment. Change one variable per shot. Change grind before anything else.
| What you taste / see | Most likely cause | First adjustment |
|---|---|---|
| Sour · Thin · Sharp | Under-extraction — shot ran too fast, water did not have enough contact time with the puck | Grind finer. One step at a time. Finer grind slows flow, increases extraction time, and extracts more sweetness.→ Also check: ratio, dose, even distribution |
| Bitter · Harsh · Dry | Over-extraction — shot ran too slow, water extracted beyond the sweet zone into bitter compounds | Grind coarser. One step at a time. If time and grind are correct, reduce shot yield slightly (try 1:1.8) to stop extraction earlier.→ Also check: water temperature — above 93°C increases bitterness in dark roasts |
| Sour AND bitter simultaneously | Channeling — water found a path through the puck and part extracted correctly, part did not | Improve puck prep before changing grind. Focus on even distribution and level tamp first. Channeling produces uneven extraction — one side of the puck over-extracts while the other under-extracts.→ Fix: Better distribution + level tamp |
| Watery · No crema · Runs very fast | Grind far too coarse, or channeling severe | Grind significantly finer. If crema is absent, the coffee may also be stale — CO₂ depleted beans cannot form crema under any conditions. Check roast date.→ Crema requires fresh coffee |
| Shot won't flow · Grinds paste-like | Grind too fine or dose too high — puck is too dense for water to pass through at 9 bar | Grind coarser immediately. At extreme fineness, pressure can build dangerously. If using a pressurised basket (standard on most home machines), the mask keeps the shot flowing but flavour will be compromised. |
Recommended for Espresso
Two Simple Coffee Espresso Products
Simple Coffee's Espresso range was built specifically for espresso and Moka Pot brewing. Each variant is a different combination of roast level and bean origin, matched to how they perform under pressure. Two variants suit different preferences best.
Recommended — Simple Coffee Espresso Range
Espresso Med-Drk Thai
Espresso Blend · Northern Thailand · 100% Arabica
Northern Thai Arabica roasted med-dark for espresso. Fruit and Sweet on the Continuum — a softer, slightly brighter espresso character with natural fruit sweetness from the Thai origin. Works well as a standalone shot and holds up cleanly in milk-based drinks without the sharpness of lighter roasts.
Espresso Parameters
Ratio: 1:2 · Temp: 91°C · Time: 25–28s · Grind: Fine
Recommended — Simple Coffee Espresso Range
Espresso Drk Thai
Espresso Blend · Thailand · Arabica + Robusta
Dark-roasted Arabica and Robusta blend — built for crema, body, and intensity. Chocolate and Roast on the Continuum. The Robusta component adds a thicker, more persistent crema and bolder mouthfeel that cuts through milk in a flat white or cappuccino. For those who want a strong, traditional espresso character.
Espresso Parameters
Ratio: 1:2 · Temp: 91°C · Time: 25–28s · Grind: Fine
Espresso is the most demanding method — and the most satisfying when it goes right. Start with the ratio, dial in the grind, and change one variable per shot. The machine is the last variable. Good puck prep on an average machine beats bad puck prep on an expensive one every time.