Is anyone else making heavy use of PID controllers?
I have an anova sous-vide controller generating cocoa butter seed; on the included picture it's set at 92.5F.
A ziploc bag at 34C for 12 hours then at 33.5C, up to 100g of cocoa butter seems to work well; I dry the bag and cut a tiny bit of a corner to use the seed, which takes care of any remaining lumps. It's also worked with a glass jar inside a ziploc bag. The same setup was also used at higher temperatures to infuse cocoa butter with spices.
On the second attached picture is another PID controller, this time a Sous-Vide Magic 1500. I used plexiglass, duct tape, a heater, fan and hacked chafing dish to assemble this heater. This probably doesn't make economic sense if you have to buy all those things - I had an old spare PID controller hanging around and wanted a proof of concept. I learned that ceramic heaters are a really bad choice and will use a hair dryer next 
Next I'm getting quotes to build the box in stainless steel and cut the chafing dish holder that would sit on top, so I can use regular restaurant-sized chafing dishes.
In another chocolate workshop I saw a micro-controller running a PID algorithm, controlling an old freezer to keep it at a higher temperature than the one it was designed for. Arduino, Raspberry Pi and others would be good choices - and given time I would get some together to have a seed generator that isn't water based and maybe hack a freezer to be a cooling tunnel.
For the moment my bottleneck is molding bars and packaging them fast enough to be able to get to break-even, so those projects have to wait. I hope this gives people ideas and this thread encourages people to share.
updated by @daniel-haran: 02/10/16 04:46:08PM
