The practicalities of roasting on-site are not that simple because we have to consider space, heat and ventilation. We have opted for a small roaster to get us started and will probably upgrade as things move forward.
This little roaster can do up to 300g of beans in any one batch, so enough for quite a few cups. In go the green beans to the roasting chamber which is then inserted into the roaster. Dial in your roast settings of duration and temperature, the longer the roast the darker. The quality of the roast is a balance between the amount of beans, length of roast and the temperature. This is a cross between a science and an art to get it right and changes between bean types.
I started off with a 15 minute roast at 240 degrees followed by a 10 minute cooling period. This was using organic beans from Peru and resulted in a medium roast which was quite acidic. Then I let the beans cool to room temperature and put them into the hand grinder. I actually ground them too fine which made the filter process very slow as the water took along time to filter through.
See the all action video of the roast in progress.