I've been thinking about my early roasting learning curve...
I've mentioned previously in this blog that the first roaster I purchased was a teeny weeny Taiwanese electric roaster good for, at most, a couple of hundred grams of green coffee. The first few roasts I did on the machine were truly nightmarish though!
I remember one of the early roasts took almost 30 minutes... and at full heating power! Compare that to my current roaster which averages about 12 minutes for a roast. That early roast tasted like ash... the ash of dreams of wonderful coffee roasting gone up in an inferno of "I don't know what the heck I'm doing".
It turns out that small roasters (especially electric ones) are quite variable in build quality and the magic balance between roasting by conduction and convection can be out of kilter. In the case of this roaster there wasn't quite enough power from the electric elements to drive the required level of convective heating. I needed to increase the thermal conductivity of the drum in order to driver more rapid and effective roasting and I did that by painting the drum of the roaster with black thermal paint. This worked a treat and the roaster became a solid roasting companion for many years!
A quick note to my Coffee Prototypers customers. The most recent roast for this product has just been sent out... the Colombian Coconut/Caramel Infusion. For the next edition, we'll be changing processing style to explore an entirely new spectrum of flavours!
Explore Coffee Prototypers Flavours!
To read a primer on espresso extraction click here
To read about pre-ground versus freshly ground coffee click here