[Noisebridge-discuss] used electronic utensils turned in to hitech food culturing devices

[Meredith L. Patterson]

On Wed, Jun 23, 2010 at 1:30 PM, Frantisek Apfelbeck 
<algoldor at yahoo.com> wrote:
>  I've quite pretty good idea what will be
>     handy and how it should look like but how to refurnish for example old
>     refrigerator to a fully automated on-line incubator is a bit mystery
>     to me which I would love to help to resolve. The key words in
>     this project are: refurnished, robust, efficient and low cost
>     (talking about hundreds of dollars max for prototypes).

I wouldn't call it particularly automated, but here's a thing I did in 
my home lab for L. acidophilus culturing. The Sharper Image makes 
travel-size refrigerators which also can keep food warm via a heating 
element -- it's an insulated box with a Peltier device, run current 
through one way and it cools down, run current through the other way and 
heats up. I never put in a real temperature control, but since lactic 
acid bacteria tend to be happy between about 39 and 41 C, I used a cheap 
probe thermometer ($6, IKEA) with an alarm that went off when the 
refrigerator got up to temperature and a lighting timer to turn the 
fridge on and off as needed (a cycle of 15 minutes on, 30 minutes off 
worked well).

Next time I find a discarded dorm fridge, I plan to rig up an Arduino 
with a thermistor and a Peltier device in order to do better temperature 
regulation. I suppose a styrofoam beer cooler would work too.

Cheers,
--mlp