How We Actually Decide When to Drop the Roast

So you've got 12 kilos of washed Ethiopian coffee, a 15-kilo drum roaster, and a customer who wants a filter roast that tastes like jasmine and bergamot. You get one shot before you burn through your sample budget. This happens to us every week. And the decisions come down to a few temperature markers that separate a bright, floral cup from a flat, ashy one.

Our take: for a filter roast, stop the roast 15–30 seconds after first crack ends. That puts you in the light-to-medium range. It keeps the acidity that makes high-grown Arabica worth the premium. And it avoids the roast-forward flavors that come with second crack. If you're roasting for espresso, push slightly darker—but never past the first few pops of second crack unless you're deliberately building a dark roast for milk drinks.

The two cracks that anchor every roast plan

First crack is when the bean pops like popcorn as steam escapes. It happens around 196–205°C (385–401°F). That's the transition into drinkable coffee and the end of light roasts (Roast Magazine). Second crack begins around 224–230°C (435–450°F) and signals the threshold for medium-dark to dark roasts (Roast Magazine). Those two events are your primary landmarks. Everything else—charge temperature, gas adjustments, airflow—is in service of hitting your drop temperature at the right time relative to those cracks.

For our Ethiopian lot, we charge at 200°C, soak for 45 seconds, then ramp to first crack in about 8 minutes. We want first crack to start at 198°C and last roughly 90 seconds. When it finishes, we drop at 205°C. That gives us a light roast with a dry surface, bright fruit, and high acidity—exactly what the customer asked for. If we let it run to 210°C, we're in medium territory, and the jasmine note starts to flatten into generic sweetness.

Quick tip: Keep a written log of charge weight, drop temperature, and time to first crack for every batch. Without it, you can't repeat a good roast, and you'll waste expensive green coffee chasing a profile you already nailed once. (We learned this the hard way after a particularly expensive Kenyan lot that we couldn't replicate.)

Why roast level names matter less than your drop temperature

Light roast is typically reached at 180–205°C (356–401°F), stopped at or just after first crack. Medium roast is 210–220°C (410–428°F), between the end of first crack and just before second crack. Medium-dark is 225–230°C (437–446°F), and dark roast is 240–250°C (464–482°F), during or after second crack (Roast Magazine). Those ranges overlap with the crack temperatures, which is why we always talk about drop temperature relative to first crack, not just a name like “City” or “Full City.”

Common light-roast names include Cinnamon, New England, and Half City; medium names include American, City, and Breakfast; dark names include French, Italian, and Espresso. But if you're buying green coffee from a specialty importer, the name on the bag may not match what you get in the drum. We've seen “City” roasts that were dropped at 208°C and tasted like a light roast, and “Full City” that hit 225°C and tasted like a medium-dark. Use the names as a starting point, then adjust to your own equipment and taste.

Matching roast level to brew method

Your brew method should influence your drop temperature. For pour over, we want a light-to-medium roast that keeps acidity and clarity. The pour-over guide from Roast Coffee Co. specifies a 1:15 to 1:17 coffee-to-water ratio, water at 200–205°F (93–96°C), a medium-fine grind, and a 3–4 minute total brew time. A light roast at 205°C drop will shine here. For French press, a medium or medium-dark roast works better because the coarse grind and long steep extract more body and less acidity. For cold brew, we recommend a medium or dark roast; the long cold extraction softens bitterness while maintaining body (Roast Coffee Co. roast levels).

Espresso is its own beast. WBC rules define espresso as a 1 fl oz beverage (30 mL ± 5 mL) made from ground coffee, poured from one side of a double portafilter in one continuous extraction. Brewing temperature must be 90.5–96°C (195–205°F) and pressure 8.5–9.5 bar. For that kind of pressure, a medium to medium-dark roast gives you the solubility and crema you need. We usually drop espresso roasts at 215–220°C, just before second crack.

Notice that we never recommend a dark roast for filter. The oils that migrate to the surface during second crack mute the delicate acids that make a single-origin coffee interesting. If you want smoky, low-acid coffee, save that for cold brew or a milk-based drink where the roast character can stand up to dairy.

What about caffeine and decaf?

Many customers ask whether a darker roast has less caffeine. The answer is no—caffeine is heat-stable and does not burn off significantly in roasting. Light roast has slightly more caffeine by weight, but the difference in a brewed cup is typically less than 5% (Roast Coffee Co. roast levels). So if you're roasting decaf, you still need to follow the same crack-based logic. In the United States, coffee labeled “decaffeinated” must have at least 97% of its caffeine removed; a typical cup of decaf has about 2 mg of caffeine, compared with about 95 mg in a typical cup of regular coffee (NCA decaf). The Swiss Water process uses only water, temperature, and time—no chemical solvents—and keeps pre-decaffeination certifications intact, including organic (Swiss Water). That makes it our preferred method for organic decaf lots.

When roasting decaf, expect first crack to happen at a slightly lower temperature and the bean to develop faster. We usually drop decaf 5°C lower than the equivalent regular roast to avoid scorching. The same crack markers apply, but the window is narrower.

Putting it into practice

Back to our Ethiopian lot. We roast three sample batches: one dropped at 200°C (light), one at 208°C (medium), and one at 218°C (medium-dark). We cup them side by side using the SCA cupping protocol, which evaluates coffee across ten attributes on a 100-point scale; scores of 80+ qualify as specialty grade (PyraBrew cupping). The light roast scores 86 with strong jasmine and bergamot. The medium scores 84 with more caramel but less florality. The medium-dark scores 81 with generic sweetness. We send the light roast to the customer and keep the medium as a backup for a future espresso blend.

That's the process: know your crack temperatures, pick a drop point that matches your brew method, and cup every batch. Don't rely on roast names alone. Don't guess. The most important thing to remember is that first crack is your anchor—everything before it is development, everything after it is a choice about how much roast character you want to trade for origin character. For filter, stop soon after first crack ends. For espresso, go a little further. For cold brew, go darker still. And always write it down.

Sources

• Roast Magazine - https://roastcc.com/learn/coffee-roast-levels
• Roast Coffee Co. roast levels - https://www.roastcc.com/learn/coffee-roast-levels
• WBC Rules - https://sca-spain.coffee/wp-content/uploads/2024/10/2023-WBC-Rules-and-Regulations.pdf
• NCA decaf - https://www.ncausa.org/About-Coffee/All-About-Decaffeinated-Coffee
• Swiss Water - https://www.swisswater.com/pages/coffee-decaffeination-process
• PyraBrew cupping - https://www.pyrabrew.com/education/cupping