DIY Sous Vide Temperature controller

[bennelson]

http://www.youtube.com/watch?v=t_FsO_4gplY#t=21

Recently, I started playing around with "Sous-Vide".

For those of you who don't know, this is a cooking technique where food is sealed in a vacuum bag and then cooked in hot water AT THE TEMPERATURE YOU WANT TO FINISH IT AT. That means it's pretty much impossible to overcook your food, and it's great for hold times, one reason that restaurants have been using it for years.

But perhaps even more importantly, it's nerdy as hell.

By building my own "Sous-Vide Controller", I can turn my Crock-Pot into a PRECISION TEMERATURE CONTROLLED DEVICE.
That means good-bye to HI/LO and hello to exactly 137 degrees.

There's already lots of good info on building your own from essentially off-the-shelf parts (Here's one of the better ones) so I won't bore you with the details. Essentially, I'm using an all-purpose temperature controller ordered from Amazon.com to turn an electric outlet on and off. I used a project box I had kicking around, so that's why it has too many holes in it and there's that gap in the front, I'm using what I had instead of spending another ten bucks to buy a box.

The setup is pretty much like a home furnace thermostat. Below a certain temperature, the controller turns the outlet on (creating heat, by turning your Crock-Pot or other heating device on) and above that temperature, turns it off (which allows the water to cool, trying to get back down to room temperature.) In this way, the temperature is always held very closely around your set temperature. This works really great for steaks! (Just sear them in a pan when all done for show!)

You might be thinking by now that this sounds like a very nerdy/overly-complicated way of cooking a steak. It's actually pretty simple, and you get super-tender food, but if you aren't a steak/venison/bison person, how does a DIY YOGURT-MAKER sound? Making yogurt requires a fairly specific temperature range. Why not drop a few mason jars into a Crock-pot, fill with your pasturized and cultured milk, and set the controller overnight for 107 degrees?

Into exotic beer-making and other kitchen science? A lot of that can use temperature control as well!

Besides kitchen uses, the controller can turn on and off any other AC appliance based on temperature. For example, you could have a light-bulb heat your chicken coop in the winter, and have it turn on and off as needed. This both keeps your birds warm and saves energy when not needed.

The only down-side I can think of is that "Sous-Vide" typically relies on the food being vacuum-sealed in plastic. Since I'm trying to get away from plastic in general, I'd like to figure out what the other options are. Mason jars are one possibility, but would require that they are completely full to conduct heat from the water bath. Canned beef stew for dinner anyone?

Anyways, I'll keep you updated as my kitchen experiments continue.

-Ben

PS: Commerical Sous-Vide appliances run $250-to $500. That's pretty pricey for a fancy Crock-Pot. I built this controller box for about $30.