Print Thread
Paper on Roasting Defects
TomC, over on Home-Barista, posted a link to a report on characterising roasting defects. There's a graph that shows the template profiles that were used to create various defective roasts. It looks to me as if the various profiles are substantially 'parallel', meaning the big differences among them are the preheat temperature and turn point temperature, the rates of change at 'time-from-TP' look very similar and the plots mostly don't cross.

I've tried the same on my popper, charging after a steady 120C setpoint and, after stabilizing ROC at 20Cdpm / 100C, gradually reducing ROC through the roast. Previously I'd been doing 140C charge and 30Cdpm through 100C etc. I can say for sure the result is better to my taste ( I'm not sure _how_ it's different ) but, more importantly,
the business of just varying the charge temperature is helping me resist winding the ROC knob all over the place during the roast.

The authors of the paper also claim to be monitoring true BT with 3mm drill holes in the bean. Their graph shows temperatures a lot lower than I expected. Would anyone have an idea where FC is on those graphs ?
True BT measurement Grin
Jump to Forum: