11
4
When the temperature rises to 125º Celsius, turn the blower control to the maximum to clear
released chaff and help dry the beans.
5
When the temperature reaches 150º Celsius, return the blower control to the minimum setting
(but not stopped).
6
About 10-20 seconds before the desired drop temperature, turn off the heat and turn the blower
control to high to suck out any remaining chaff.
7
At the desired drop temperature, open the drum door to let the beans out into the collector bin.
8
Immediately place the collector bin in the cooling chamber for two or more minutes with the
blower on high to stop the roast, or use an external cooler.
Profile 2
This profile demonstrates how to vary the controls to create a new profile.
1
Begin the same as for Profile 1, up to and including step 5.
2
Upon hearing the start of 1C, turn the heater control so that the current drops one mark on the
ammeter.
3
Mid-way through 1C, turn the blower control up by one digit.
By limiting the heater current, one can roast smaller batches using these two profiles. Roasting
smaller batches makes the roaster more responsive. For example, in the M6, a 350-gram roast
can be done by setting the heater current to about 9-Amperes (120-volt model).
These are merely examples of how to profile. Achieving mastery and consistency requires considerable
practice and experimentation to understand how each adjustment influences the roast. The best way to
proceed is to reduce the number of variables. Roasting a consistent sample size and sticking with a
single type of bean are two examples. Other variables include the temperature at the time of charge,
varying the temperature during various phases of the roast, varying the blower speed, and
lengthening/shortening the overall roast time.
Adjustments:
When cupping the coffee, make a note of any defects. If it is sour, aim to shorten the
roasting time on the next roast using a bit more heat or charging at a higher temperature. If it is bitter,
lengthen the roasting time using a bit less heat or charge at a lower temperature. If the roast is
underdeveloped, increase the time between 1C and 2C by lowering the heat a little immediately before
1C. Make all such changes in small increments to better learn from your changes; for example, when
reducing or increasing heat, do so one graduation at a time on the ammeter.
Do not confuse roasting deficiencies with brewing deficiencies when tasting
; both processes
can produce sour, acidic or bland coffee. To properly analyze a roast, one must "cup" the
coffee. Cupping is a specific process of brewing and analyzing, which is beyond the scope of
this handbook.
Here are some rough guidelines to correct roasting defects, based on an overall roast time between 11
and 22 minutes, in three phases.
Phase
Too Short
Good
Too Long
