Why this roast exists

This was a second ~52g sample roast to continue the small-batch consistency experiment — but this one was started intentionally on a warm machine to see what changes (and what doesn’t).

Coffee

  • Coffee: Costa Rica San Isidro 48 Red Honey (Finca Carrizal)

Setup (what I actually did)

  • Roaster: Gene Café CBR-301
  • Batch size: 52.5g green
  • Set temperature: 250°C
  • Start condition: warm start (start temp logged at 52°C)
  • Cooling: stopped based on colour looking “about right” (and overall feel of the roast)

Measured results (from the roast log)

  • Roast date/time: 2026-02-09 20:55:51
  • Weight in → out: 52.5g → 44.3g
  • Weight loss: 15.6%
  • Total roast time (cooling initiated): 11:47 (707s)
  • End temperature: 244°C
  • Max temperature: 252°C
  • Fan behaviour: Fan 2 → 3 at 3:51, then 3 → 2 at 7:28
  • Crack marker in app: not flagged

What I observed during the roast (notes, not claims)

  • I thought I heard a few pops, but it didn’t build into a clear crescendo for me.
  • The machine still showed the same familiar airflow/protection shape (fan stepping up, then recovering back down).

Interpretation (kept deliberately modest)

  • Starting warm clearly changes early pacing (everything gets hot sooner), but the roast still settles into the machine’s normal rhythm later on.
  • Even though the end temperature was lower (244°C), the weight loss was higher (15.6%), which is a good reminder for me that “end temp” isn’t a reliable roast-level marker on this roaster.

What I’ll do next

  • Brew after rest and evaluate structurally: body, balance, finish.
  • If I do more sample roasts for comparison, I’ll avoid warm starts unless I’m specifically testing warm starts — it makes comparisons harder.

Source: Gene Café roast log export (JSON)