Grind that blonde coffee up and feed it to the compost pile. If the roasting of coffee is interrupted that is it - it is over you only get one shot at it.
I started roasting coffee in a pop corn air popper. Not a great device but will get the job done. I have built and bought various devices over the past 8 years. I use a drum roaster now.
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I has a bunch of programs that may or may not work, I don't use them. I roast by sound, smell and smoke. The start of first crack means it is about 90 seconds to fullcity and another 15 or 20 seconds to fullcity+. These are my preferred roast levels for espresso.
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