Coffee Science Update

Wednesday, March 18, 2009 

Magnetically stirred coffee seems to be a success, but still tuning the parameters. I have a surplus temperature control module connected to a thermocouple probe to monitor the temperature.
My first attempt was confounded by not programming the controller to read a K-type thermocouple, it came set for a J-type and so the water never got over 88C even boiling… which it did for a while and that’s not good. Not good at all.
Today I let the water temp get up to 80C and the coffee was very good, smooth and not bitter at all. Perhaps a bit too smooth, a bit like the cold-brew taste but warm and much faster thanks to the stirring action. I will try 90C tomorrow and if success continues, modify the hotplate to add a direct thermal element bypass to the outside so the temp controller can control the heater directly (now I just watch and turn off the heater at the target temp.)
The theory is that by continuously stirring the coffee, a lot of flavor is extracted without relying on heat, and that the stirring also ensures uniform heating through the entire volume and thus the temperature can be set fairly precisely (to about a degree C, +/- 1 degree or so) to optimize differential extraction of the organics in the grounds.

DSCN5486.JPG
Posted at 16:00:26 GMT-0700

Category: Related Links

Aggro Spider

Wednesday, March 18, 2009 

There was a cool looking spider (apparently Phidippus johnsoni or the literally named “red backed jumping spider” )  exploring my monitor, nice red  abdomen
what are you looking at.jpg
He sees me taking his picture and gets pissed and jumps at the camera – BAM! then jumps back to the monitor.

what are you looking at spring.jpg
Cool!  So I tried to take another shot and this time he gave me a look like “I may be small, but you’re going to regret this if you don’t leave me alone” and smacked my camera again.

what are you looking at spring want some more.jpg
Posted at 01:35:05 GMT-0700

Category: funnyphoto