Home Roasting Guide
Roasting your own coffee is simpler than it sounds: heat, movement, and attention. This guide covers the equipment, what happens inside the bean at each stage, how to hit the roast level you want, and how to fix the roasts that go sideways.
Every method works on the same principle — hot air or a hot surface, plus constant agitation so the beans brown evenly. What changes is batch size, control, and how much smoke you'll deal with.
The classic starter. Fast, bright roasts with very little control over heat — you manage the roast by batch size and timing. Chaff blows out the spout, so run it outdoors or over the sink.
Cast iron over medium-high heat, stirring without pause. Expect some unevenness and a lot of smoke, but it teaches you to read color and sound better than any machine.
A purpose-built hot-air roaster with fan and heat controls and a chaff collector. Clean, quick, and consistent — the natural upgrade from a popper.
A rotating drum heated from below, like a scaled-down café roaster. The most control over the roast curve, bigger batches, and the ability to repeat a profile exactly.
Skip the oven. It's possible, but the beans sit still, brown unevenly, and you can't hear first crack over the fan. If you want a no-equipment start, the skillet is the better lesson.
Temperatures below are approximate bean temperatures. Machine readouts vary — trust your eyes, nose, and ears more than the number.
Roast level is decided by when you drop the beans relative to the two cracks. Lighter roasts show the coffee's origin; darker roasts show the roast itself.
Bright acidity, floral and fruit notes, lighter body. Dry surface, no oil. The most honest expression of a single-origin bean.
Balanced — sweetness, body, and acidity in proportion. Caramel and chocolate start to show. Still a dry surface. The safest target when learning a new bean.
Bittersweet, dark chocolate, low acidity, heavy body. A few oil spots appear. Classic espresso territory.
Smoky, roasty, little acidity, thin body. Glossy with oil. Origin differences mostly disappear — use an inexpensive bean here.
This sequence is the same on a popper, a skillet, or a drum roaster — only the timings change.
100–250 g depending on your roaster's capacity. Too big a batch is the most common reason for slow, baked roasts. Note the green weight — you'll compare it after.
Bring the roaster to temperature before the beans go in. A cold start stretches the drying phase and flattens the cup. Poppers: run empty for 30 seconds. Drums: 350–400°F charge.
Add the beans and start the clock. From here on, beans never sit still — agitation is what keeps color even and stops scorching.
Green → yellow → tan → brown. Grass → bread → caramel. Then the pops of first crack. Note the time it starts; that number is your anchor for every future roast of this bean.
After first crack, the roast moves fast. Decide your drop point before you start (see roast levels) and stick to it — hesitating 30 seconds is the difference between medium and medium-dark.
Dump immediately into a metal colander and stir or fan until the beans are cool to the touch — under 4 minutes. Beans keep roasting on their own heat until you stop them.
Toss the beans between two colanders outdoors, or blow across them with a fan. Chaff is harmless but adds a papery note if it ends up in the grinder.
Weigh again — 12–15% loss suggests light, 16–20% dark. Rest 12–24 hours (3–5 days for espresso) in a container with a one-way valve, then brew within 2–4 weeks.
Cooling is part of the roast. A 400°F bean carries enough heat to keep developing for a minute or more after it leaves the roaster. Slow cooling pushes a planned medium roast toward medium-dark and dulls the aromatics. Spread the beans thin and move air across them — a box fan under a colander works as well as anything.
Fresh-roasted is not the same as ready. Roasting produces a lot of CO₂ that keeps escaping for days. Brewed too soon, the coffee tastes sharp and hollow and pour-overs bloom uncontrollably. Give filter coffee 12–24 hours; give espresso 3–5 days, since gas interferes with extraction under pressure.
Store roasted coffee in an opaque, airtight container with a one-way valve, at room temperature, away from the stove. Not the fridge — condensation is worse than air. It peaks between day 3 and day 14, and is still good to about a month.
Store green coffee in a cool, dry, dark place in a breathable bag or a bin with a loose lid. Kept around 60–70°F and out of humidity, green beans hold their quality for 12–18 months — which is why it's worth buying green in larger bags than you'd ever buy roasted.
Repeatable roasts come from written notes, not memory. Record these for every batch — after five or six roasts of the same bean you'll be able to dial it in on purpose.
| Bean & lot | Origin, process, and the lot number from the bag label |
|---|---|
| Green weight / roasted weight | Weight loss % tells you roast level more reliably than color |
| Charge temperature | Roaster temperature when the beans went in |
| Yellowing time | When the last green disappears — end of drying |
| First crack start & end | Your anchor points. Aim for first crack around 8–10 minutes on a drum, 4–6 on a popper |
| Drop time & temperature | Total roast time and bean temp at the drop |
| Development time ratio | Time after first crack ÷ total time. 18–25% is a good starting range for filter coffee |
| Tasting notes (day 2 & day 7) | What you actually tasted, and how it changed with rest |
| Next time | One thing to change — only one, or you won't know what worked |
Almost every defect traces back to heat that was too high, too low, or applied too late. Match what you see and taste to the cause.
Every green coffee we sell lists its origin, process, elevation, harvest, moisture, and screen size — everything you need to plan the roast before the beans arrive. Available in 5 lb and 10 lb bags.