Common Issues for New Roasters

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We field calls on a daily basis. Let’s take a look at the most common errors as you begin to learn that new roaster.

Not using full charge.
North roasters are designed to use full charge. Don’t go smaller in charge size until you have mastered the full charge roasting profile. Then master a 90% of capacity, 80% of capacity, 70% of capacity. Most roasters generally advise not going below 50% of capacity. (Note: I can do 200g sample roasts on our 1K with a slight variance is color).

Getting glued to profiles.
Don’t do that. Software is a tool. It is to assist your eyes, your ears, your nose, and your palate. Trust yourself. Learn to cup!

Turning off the burners on 3Ks and above.
Many of our videos have us working on the 1K on the bench. We turn the burners off for one minute just because we have so much heat. On 3K and above roasters, don’t mimic that. Leave your burners on.

Failing to cup.
Your roasts should be cupped. Of course not every roast, but cup every week. Learn what profiles are working for a coffee and which ones can be tweaked to improve the cup. Find 3 others who wish to learn coffee. Cupping in a group leads to exponential learning.

Struggling to get rate of rise (ROR) to 32-36*F for 1:30-1:45 minutes during drying.

On 3Ks and above, do not turn off the burners. Only on our 1 and 2Ks, do we use 1 minute with burners OFF at the start of our roasts. Try shorter or no periods of burners on OFF. Play around with it.
Gas pressure may be too low. It is possible that your utility’s natural gas pressure is insufficient or that you have your high pressure propane regulator is not set high enough.
You are overloading your roaster. Stay within rated capacity when roasting.
Your airflow is set too high.

Confused about airflow.

• Ignore your friend’s airflow settings. Your roaster is unique.
• Use this YouTube video to set and mark your three settings for roasting.
• Write down your settings. They may be in a tight lo/med/high range (20/24/28) or a wide spread (35/55/75). Numbers are relevant only to your machine.

Not knowing what charge temperature at which to drop.
Learn you coffee’s density by weighing 1L in a graduated beaker. The higher the number, the more dense the coffee is. Denser coffees can manage higher charge temperatures (as read by the PID Controller Temp on your control panel). Write down every origin’s density in your notes.

Wide variation in color in my roasts.

• Your drum speed may be too low. Shoot for a 50-55* slope in the drum. Look through the sight glass.
• Your coffee may have mixed maturities or different growing elevations.

The coffee isn’t good enough.
We field calls from roasters who are trying to make a silk purse out of a sow’s ear. $2.02/lb coffee can not be improved by roasting it. It will remain $2.00 coffee.

Need help? Feel free to give us a call on your roasting challenges. We are here to ensure that you are successful.

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