After overshooting into dark roast territory twice with Khun Kong Peaberry, I approached Mae Ukho with cautious optimism and hard-earned lessons. The goal: achieve an actual medium roast, not accidentally sprint past it. For the first time on the Kaleido M6, I succeeded.

Building on M6 Experience
Several roasts in, I’m finally starting to understand the M6’s bean temperature (BT) behavior, how it responds to heat adjustments, how quickly momentum builds, and crucially, how to slow things down before they run away from me.
For this first Mae Ukho roast, I loaded 380 grams, not too small to create erratic heat behavior, but conservative enough to stay flexible if things went sideways.
The Roast: Controlled Aggression
Dry End Strategy
At approximately 153°C, I hit dry end right where expected based on Mae Ukho’s similar density (0.73) to my Mae Salong beans. This is where previous roasts had gotten away from me—I’d failed to reduce heat aggressively enough, and the beans would sprint through Maillard.
This time, immediately after DE, I reduced heat and increased airflow. These dual adjustments work together: less heat input slows the charge, while increased airflow carries away excess heat and prevents stalling.
Maillard Phase
The result? A 2-minute 22-second Maillard phase before first crack. Still faster than ideal—I’d prefer 3-4 minutes for full sweetness development—but significantly better than the sub-2-minute rushes I’d experienced before.
Progress, not perfection.
First Crack Window
Mae Ukho announced first crack around 179°C—slightly lower than Khun Kong’s 183°C. The crack progression was notably long, continuing until approximately 187°C. That 8-degree window gave me time to assess, adjust, and plan my next move rather than panic-reacting.
With Khun Kong’s lessons fresh in my mind, I reduced heat again during first crack, trying to give myself cushion before second crack.

The Second Crack Question Mark
Here’s where things got interesting and where I learned something valuable about my own ears and the M6’s acoustics.
Around 194°C, I thought I heard second crack beginning. My notes from previous roasts screamed warnings: SC happens earlier than you think! Drop now or face dark roast consequences!
But something felt different. The sounds weren’t as definitive as I’d expected. The beans looked right for medium roast through the sight glass. I hesitated, listened harder, watched closely.
I dropped at 196.6°C, bracing myself for another accidentally-too-dark outcome.
The Reveal: Actually Medium
After cooling, the beans told the truth: genuine medium roast. Not even pushing toward medium-dark—solidly in the target zone I’d been chasing.
Conclusion: What I thought was second crack at 194°C wasn’t. Based on the final roast color and development, Mae Ukho’s second crack likely begins closer to 200°C, not 194°C.
This discovery is crucial. I’ve been dropping too early based on phantom second crack sounds, sacrificing development time and potentially leaving flavor on the table. The M6’s drum noise and soundproofing continue to challenge my audio cues, I need to trust temperature, time, and visual assessment more than questionable crack sounds.

What Worked This Time
Three things made the difference:
- Aggressive post-DE heat reduction + airflow increase – Finally slowed the Maillard rush
- Heat reduction during FC – Gave me breathing room approaching SC
- Trusting multiple data points over audio alone – Temperature, visual, and experience beat uncertain crack sounds
Next Roast: Refining Further
With 600 grams of Mae Ukho remaining, my next roast will target:
- Longer Maillard phase: 3-4 minutes instead of 2:22, to fully develop those palm sugar notes
- More confident development: Now knowing SC is around 200°C, I can develop more assertively through 195-198°C
- Better heat control earlier: Start reducing heat slightly before DE to ease into Maillard smoothly
For the first time, I’m building on success rather than correcting mistakes. That feels like real progress.
Roast Status: Success – Medium achieved
Key Discovery: SC @ ~200°C for Mae Ukho
Next Action: 600g roast with extended Maillard phase in a couple of days
