Hi Khalid.

Bigger roasters roast longer. Green/yellow transition around 6 minutes isn't a big deal. 12 minute first crack is okay. Your graph shows only 45 seconds of post first crack development. That's a big problem.

Is that what happened here or do I misunderstand?

Hi Steve

why is 45 seconds a big problem?

I usually take between 45 Sec to 90 Sec for post-FC depending on the coffee seeds and it was a great batch sweet and balanced and my finish temp as I wanted 210 C

Hi Khalid.

Coffee flavor is a function of avoiding heat defect while heating the seed in a way that balances inner vs. outer seed color.

The short post first crack development time you describe usually results in a lighter inner seed color and more raw or undeveloped flavor notes.

You wrote "when I tried the same setup for 10 KG it took me 16 Min and it was so bad I threw it away."

Why exactly did you throw it away?

Hi Steve

I threw it because the taste was burnt I suspected that maybe because it was the first batch after seasoning the drum but I tried another batch same result so I reduced the batch to 8 KG and it was as I expected in terms of flavor and time.

to be honest I cleaned the drum with a dry towel before the 8 KG batch and I never tried the 10 KG due to having a limited supply of coffee seeds for testing.

for your point regarding the 45 Sec post-FC I didn't face any of your concerns, the notes were balanced, sweet, and fruity

however, I know there is much potential that I didn't unlock from this coffee but it is a lifelong journey I will figure it out eventually.

Have you completed the set up and seasoning roast calls with Aziz?

We should verify your installation before we try to troubleshoot roast issues.

Hi Steve

yes, we completed that and the setup was great, I learned a few tricks from Aziz and he noticed that my gas regulator should be 35 mbar which is not available in Kuwait we used 30 mbar for domestic use I had to order the regulator from Spain it will be delivered next week.

there is no issue with my roaster just it took a long time to roast and you mentioned that because it is a big roaster it takes time.

thank you for the follow up I appreciate your effort.