Decaf Coffee Beans for Espresso: How to Dial Them In
Most guides on decaf espresso say something like "treat it the same as regular coffee" and leave it there. Which is fine advice, up to a point — but it doesn't explain why your decaf keeps pulling differently to your regular bean on the same settings, or what to actually do when it does.
The reason decaf coffee beans behave differently on an espresso machine comes down to something the decaffeination process does to the bean's physical structure. Once you know what that is, the grinder adjustments are straightforward. That's what this guide is actually about.
Why Decaf Beans Extract Differently
This is the part most guides skip, and it's the part that actually matters.
The Swiss Water Process — the decaffeination method used for Simmer Down — works on green, unroasted coffee beans. The beans are soaked in water to draw out the caffeine. That water immersion swells the bean's cell walls and changes their internal structure. The bean is then dried and later roasted, but the structural change from the water process persists. The result is a bean that is slightly more porous and marginally less dense than a regular coffee bean from the same origin roasted to the same level.
On an espresso machine, porosity matters a lot. A more porous bean lets water move through the puck faster. At the same grind setting you use for regular coffee, that faster flow means the water doesn't spend enough time in contact with the coffee — you get under-extraction. Sour, thin, unsatisfying.
How roast level affects this
The gap between decaf and regular bean behaviour is not fixed. A medium roast decaf has more of this porosity difference because medium roasting doesn't break down cell structure as dramatically as dark roasting does. Dark roast decaf — where the roast itself is doing significant work on the bean's internal structure regardless of the decaffeination — narrows the gap considerably.
Simmer Down is a medium roast, which means you'll likely need a small grinder adjustment. Not dramatic. But worth knowing before you pull your first shot and wonder why it ran fast.
What this means for the grind
The practical implication is simple: to compensate for faster water flow through a more porous puck, you need to slow the shot down. The easiest way to do that is a slightly finer grind. Sometimes a slightly higher dose helps too. In most cases you're not talking about a major recalibration — one or two clicks on a stepped grinder, a small nudge on a stepless one. But if you switch from your regular bean to a decaf at identical settings and pull straight away without adjusting, expect the shot to run fast.
How to Dial In Decaf Espresso
There's a temptation when switching to decaf to treat it as a completely different category of thing that requires a completely different approach. It doesn't. The process is the same as dialling in any espresso — you're just starting from a slightly different point.
Step 1: Pull a shot at your normal settings first.
Before touching anything, pull one shot at your usual grind, dose, and yield. Taste it. A lot of people skip this and go straight to adjusting, then end up chasing a problem that may not have been as bad as they assumed. Some decafs — particularly darker roasts — extract close enough to regular coffee that the adjustment needed is minimal. Find out what you're actually dealing with before you start moving dials.
Step 2: Diagnose what's wrong.
Sourness is under-extraction — the shot ran through too fast and not enough dissolved from the coffee. Grind finer.
Bitterness is the opposite. Too much contact time, or a grind that's already too fine. Open it up.
If it tastes weak but not sour — watery, lacking body — the dose is probably the issue rather than the grind. Try adding half a gram and pulling again before you start moving the grinder.
Pale crema or no crema is normal with decaf. Not a sign of bad extraction. More on that below.
Step 3: Adjust grind first, dose second.
Grind is the primary variable. Change one thing at a time. If you adjust both grind and dose simultaneously, you won't know which change fixed the problem — and you'll repeat the confusion every time you switch beans.
For most medium roast decaf, go a step or two finer than your regular setting and pull again. That's usually enough. If the shot is now pulling too slow or tasting bitter, you've gone too far — come back one step.
Step 4: Settle on a recipe.
A standard espresso recipe works well for decaf: 18g in, 36g out, 25–30 seconds. Some people prefer to push toward a slightly longer ratio with decaf — 1:2.5 or 1:3 — to compensate for a marginally lighter body. Taste is the guide, not adherence to a number.
Step 5: Write it down.
Decaf isn't usually the daily driver — most people who buy Simmer Down are drinking it in the afternoon or evening, which means the bag lasts longer and the next time you return to it you'll have forgotten the settings. Note the grinder position, the dose, and the yield. Takes thirty seconds and saves you re-dialling from scratch.
Dialling In on Specific Machines
Sage Barista Express
The Barista Express has a stepped grinder with an inner burr setting and an outer adjustment ring. For decaf, most users find they need to go one or two steps finer on the inner burr compared to their regular coffee setting — the outer ring is better for coarse adjustments, the inner burr for the fine work. Start finer than you think you need and work backwards if the shot pulls too slowly. It's easier to open the grind up from an over-extracted shot than to recover from several shots' worth of wasted coffee chasing a fast pull.
Sage Bambino
The Bambino has fewer grinder adjustment points than the Barista Express, which makes the transition between beans slightly less precise. If you're regularly switching between a regular bean and a decaf, it's worth using a separate hand grinder for the decaf and pulling shots with the pressurised basket — this keeps you from re-dialling the machine's built-in grinder every time. If the built-in grinder is your only option, move one step finer for the decaf and evaluate from there.
Bean-to-cup machines
Most bean-to-cup machines handle decaf without much drama. The machine adjusts pressure automatically, which takes some of the finesse out of it. If output seems weak or under-strength, find the machine's internal grind setting and nudge it a step finer — usually accessible in the settings menu. The one thing to avoid is mixing decaf and regular beans in the same hopper. Two beans with different extraction behaviours trying to work together through one machine setting gives you inconsistent results neither bean deserves.
If you're serious about espresso — from decaf or any other bean — a dedicated grinder gives you a level of control that built-in machine grinders don't. Not a prerequisite for good decaf espresso, but it makes the whole process less frustrating.
Does Decaf Espresso Produce Crema?
Yes. But less of it, and it doesn't last as long. This is normal, and it's worth knowing before you pull your first shot and conclude something has gone wrong.
Crema forms from CO2 dissolved in the coffee during extraction. That CO2 comes from the bean — freshly roasted coffee off-gasses CO2 over the days and weeks following roasting, and the gas that's still trapped in the bean when you pull the shot contributes to crema formation. Decaf beans are more porous, which means they off-gas faster. By the time you're brewing them, there's often less dissolved CO2 available, so the crema is thinner and dissipates more quickly.
This is cosmetic. A well-extracted decaf espresso with light crema tastes the same as — often indistinguishable from — a regular espresso with a thick crema. The crema is not the coffee.
Freshness helps more with decaf crema than with regular coffee. Roasted-to-order decaf (Simmer Down ships the day it's roasted) produces noticeably better crema than beans that have been sitting in a warehouse for a month. Rest matters too — give the bag at least seven to ten days after roasting before pulling shots. The standard espresso resting window applies here just as it does with any other bean. Don't open it the day it arrives and pull straight away.
Decaf Espresso as a Milk Drink Base
Decaf pulls well under milk. Medium roast decaf in particular — where the roast has developed sweetness and body without pushing into bitter territory — holds up in a flat white or latte without the espresso getting lost.
Simmer Down's vanilla fudge and caramelised biscuit notes were noted by Great Taste judges specifically in the context of a milk drink: "with milk, it becomes a vanilla fudge — soft, round, full of malt." That's a good flat white. The judges didn't know it was decaf when they wrote that.
If you're making decaf flat whites and finding the coffee flavour is getting swallowed by the milk, try a ristretto-style pull — shorter ratio, more concentrated, same or slightly higher dose. This compensates for the marginally lighter body you sometimes get from decaf and gives you a more expressive espresso base. A 1:1.5 or 1:2 ratio works well here.
One thing to avoid for milk drinks: very light roast or high-acidity decaf. Delicate origin notes that are interesting to drink black tend to disappear under steamed milk. Medium roast is the practical choice for lattes and flat whites.
For more on what makes a good espresso base for milk drinks, see our guide to the best coffee for a flat white.
Simmer Down Decaf
We've mentioned it throughout, so here's the full picture.
Simmer Down comes from Cajamarca, a high-altitude growing region in northern Peru. Bourbon and Typica varietals, washed process, medium roast. Strength 3 out of 5 — which in practice means it's forgiving to dial in on espresso and works as well black as it does under milk.
Swiss Water processed. No chemical solvents. 99.9% of the caffeine removed from the green beans before roasting. Like every coffee in our Roastery Collection, it's independently lab-tested for mycotoxins, moulds, and artificial pesticides before it ships.
The Great Taste judges called it "a darker roast that delivered a rich crema" and noted that "no one would guess this was a decaf." We're inclined to agree, though we're obviously not neutral.
Available whole bean or pre-ground for espresso, cafetière, filter, or Aeropress. Roasted to order, same-day dispatch, free next-day delivery over £15.
If you're stepping down from regular coffee rather than cutting it out entirely, Simmer Down 50% Decaf is the same bean as a 50/50 blend — same Peru origin, same roast, roughly half the caffeine.
Frequently Asked Questions
Can you use decaf coffee beans in an espresso machine?
Yes — decaf pulls on an espresso machine the same way as regular coffee. The main practical difference is that decaffeinated beans are slightly more porous, so water moves through the puck a little faster at the same grind setting. You'll likely need to grind slightly finer than your usual setting. The adjustment is usually small — one or two steps on a stepped grinder.
Why does my decaf espresso taste sour?
Sourness in espresso means under-extraction — the shot ran through too quickly. With decaf beans, this happens more readily than with regular coffee because the decaffeination process leaves the beans more porous. Grind one or two steps finer than your normal setting and pull again. If you're on a Sage, work on the inner burr adjustment first.
Why does my decaf espresso taste bitter?
Bitterness means over-extraction — too fine a grind or too much contact time. Open the grind slightly. If you've gone very fine trying to slow a fast shot down and ended up with bitterness, try backing off the grind and adding a small amount to your dose instead. The two adjustments often work better together than either does alone.
Does decaf coffee produce crema?
Yes, though usually less than regular coffee and it doesn't hold as long. Crema comes from CO2 dissolved in the espresso during extraction. Decaf beans are more porous and off-gas CO2 faster post-roasting, so there's less available when you pull the shot. This is cosmetic — it has no effect on flavour. Freshly roasted decaf and a proper resting period of seven to ten days after roasting both improve crema noticeably.
What grind setting should I use for decaf espresso?
Start at your normal espresso setting and pull a shot before adjusting anything. If it runs fast or tastes sour, go finer — one or two steps on a stepped grinder, a small nudge on a stepless one. Most medium roast decaf needs a slightly finer setting than the equivalent regular coffee. Dark roast decaf needs less adjustment, sometimes none.
Can I use decaf beans in a bean-to-cup machine?
Yes. Most bean-to-cup machines handle decaf without significant changes. If the output seems weak or watery, use the machine's internal grind setting to go slightly finer. Avoid mixing decaf and regular beans in the same hopper — the extraction behaviours are different enough to cause inconsistency in the cup.
What is the best decaf for espresso in the UK?
Look for a medium roast decaf from a speciality roaster that uses the Swiss Water process. Chemical-free decaffeination preserves the bean's original character, which matters more on espresso than in any other brew method — the extraction process amplifies everything, good and bad. Freshly roasted beats anything sitting on a shelf, and single origin decaf tends to have more to offer than anonymous blends.
