Silver Case

I’ve done a few small batches so far. The first two batches of PNG I carbonized. Then I tried a batch cooked much lighter. It acted really weird in the espresso machine. The water blasted through at light speed, just roared through the portafilter. Even after I made the grind considerably finer, it rocketed through.

Two considerations: 1) are the default iRoast profiles too hot? 2) are 75g batches too small and get cooked too quick? [I seemed to be finishing up quite early in the roasting profiles]

So today I tried another batch, using a customize profile I found online, on a 150g batch. I used brazillian beans this time, hoping that would make a more appropriate espresso single-origin.

I did the roasting, profile shown above. They nominally look ok. I have to wait for 4-14 hours while the beans outgas CO2. In the meantime, I charted the temperature telemetry I captured from the onboard thermometer.

The colored bars are the target temperatures during the three stages. Sort of silly. It doesn’t seem to have much control on the temperature. It seems to steer it more like a freighter than a golf cart. I can program up to five stages (totalling a dead limit of 15 minutes). I suppose once I have enough of this telemetry, I can figure out approximate over- and under-steering on this thing’s temperature control.

I’ll see how the coffee tastes later.

This entry was posted on Saturday, April 14th, 2007 at 4:07 pm and is filed under Coffee, iroast.You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.