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Anyone who has spent much time working in a chemistry laboratory has probably shared my idle thought, on returning to their home kitchens, that the traditional technology of cooking is frustratingly imprecise. Though I appreciate the great received traditions of intuitive cooking as much as the next guy, I often wish for a temperature controlled, time-programmable range top—ideally with built-in overhead stirring, a gas-tight cooking vessel, a vacuum pump, and maybe an inert gas line–to repeatably and accurately control the full pressure/temperature/time space of the stuff in the pot.

We’re not there, yet, but the technology is getting cheaper. And the DIY sous-vide experimenters are leading the way, at least as far as home users are concerned.

“Sous-vide” is fashionable French for a method of cooking that involves longer cooking times at lower temperatures and reduced atmospheric pressures. It means, literally, “under vacuum.” Commonly, food is sealed in plastic vacuum bags and cooked at temperatures well below the boiling point of water for dozens of hours, although the particular parameters vary widely with the food to be cooked. The point, really, is that the equipment involved is capable of finer automated control of those parameters than your conventional range, oven, and/or microwave, and the quality and flavor of the natural ingredients can be vastly improved—without sacrificing safety—by using it.

In the title video, which has been wildly popular since we first posted it back in November, Cooking for Geeks author Jeff Potter demonstrates a very simple DIY sous-vide setup using a cheap slow cooker regulated by a low-cost digital temperature controller and thermocouple. Basically, his method involves building a temperature-controlled extension cord. The slow cooker (or whatever you plug into it) will be turned on or off as needed to bring the temperature up to the programmed setting and keep it there. Jeff suggests starting with sous-vide eggs by cooking raw eggs in the shell (which don’t require vacuum-sealing) at 148° F for one hour.

With a bit more time and effort, it’s straightforward to build an all-in-one unit that combines a digital temperature controller, a thermocouple, and a circulating immersion heater, a big advantage of which is that you can attach it to pretty much any cooking vessel you choose. Scott Heimendinger designed, built, and documented a great one for us in MAKE Vol 25, and the build is now featured on Make: Projects.

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Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I write for MAKE, serve as Technical Editor for MAKE magazine, and develop original DIY content for Make: Projects.


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Comments

  1. Mikey Sklar says:

    Jeff’s video inspired me to make a all purpose kitchen controller in kit form for other Makers. The idea is to just have a smart “outlet” than any appliance can plug into. I regularly make cheese using a electric hot plate connected to this temperature controller. It also works just fine as a sous-vide connected to a crock pot. It even runs a chest freezer as a refrigerator to save energy. It doesn’t take much to start automating your meals and have some real precision in the kitchen.

    http://store.holyscraphotsprings.com/index.php?main_page=index&cPath=2

    1. Steve Olsen says:

       Hey Mikey, is it possible to use the controller with 220-240 in Europe…and can you ship to Europe, France to be specific) :)

      Thanks!

  2. Tim Kemp says:

    “We’re not there, yet” And we probably won’t be there in the foreseeable future.

    I have worked as an engineer for two appliance manufacturers and the inaccuracies in the cooking temperatures aren’t an accident.  The temperature in your oven could easily be kept constant.  However, if was, Grandma’s cookie recipe wouldn’t work.  Cooking times and temperatures for most recipes were determined empirically using inaccurate ovens with terrible temperature regulation.If you have a way to log the temperature in your oven give it a try.  You will see the temperature ramp up quickly and completely miss the mark by overshooting by 50-100 degrees F.  Then you will see it settle down to a nice sawtooth wave with an amplitude of 25-50 degrees F.This waveform is defined by the food science people at the manufacturer.  They cook different foods and play with the cooking parameters to make sure that this year’s new whiz-bang oven cooks your food the same way that your old one does and that your parent’s stove did.  The oddities of old electromechanical temperature controls are duplicated using modern electronics.

    None of this is to say that specialty products won’t come out that will work differently.  Many manufacturers (including the one I work for) have cooking products in stores and in development that do a lot of cool things, but it’s unlikely that any of them will abandon the time-tested inaccuracies any time soon.

  3. Eggs boiled at precisely 170 degrees are NEVER overdone or sulfurous… delicious!

    http://www.seriouseats.com/2009/10/the-food-lab-science-of-how-to-cook-perfect-boiled-eggs.html

  4. Leigh Jones says:

    I am a home cook who has used sous vide techniques for years now. I could not cook without it anymore. The reason is that I come home from work to a CrockPot containing a fully cooked beef roast, pork tenderloin, or boneless/skinless chicken breasts and have only minor time and effort remaining before my family meal is on the table. Yes, the results are better than traditional methods, too, but the real advantage is ease of meal preparation.

    I use a Rival oval 7 quart CrockPot SCV700B with a Johnson Controls A419 thermostat and aquarium air pump and air stones to keep the water circulating. ZipLock freezer bags (gallon for roasts, quart for chicken breasts) are as effective as vacuum sealed bags for cooking — though the vacuum sealed bags may be better for keeping unopened meats in the refrigerator after preparation. There’s a technique to be learned for letting air escape under water…

    The CrockPot is really a good choice for this. Cleanup is remarkably easy with a few drops of lemon juice to remove hard water stains. The stoneware goes into the dishwasher! You can’t do that with a Sous Vide Supreme!

    Most sous vide do-it-yourself builders are excited by the PID controllers, but my experience with PID controllers has been spotted. In my neighborhood there are very short (under a second) power outages about once per month. I think they are “switching” episodes. My JLD612 PID controller just shuts down when this happens, and unless I am at home the meat rots. The A419 thermostat recovers and goes on to cook the meal.

    The thermostat results in some water temperature oscillations that might make PID controller users uncomfortable with the loss of control, but a meat thermometer inserted in the roast or chicken breast shows that these do not affect the temperature inside the meat. The meat just holds steady at the average water temperature.

    And the results cooking trump any ideas that the thermostat isn’t adequate. I am now experienced at close to 550 sous vide entrees with this equipment. About a third have been beef, 24 hours at 131F, about a third have been chicken breasts 140 F for 12 hours (4-6 would be preferred, but I have to start the meal before leaving for work). The remainder is pork, 138F for 24 hours. This stuff goes into stews, soups like gumbo, stroganoff, chow mein, etc., or will be served with barbecue sauce or gravy or sauces made from the bag juices. Tri-tip roasts are a favorite, Santa Maria style. The key is to let the meat cool a bit before searing to prevent overcooking, and letting the veggies etc. cool to around the target temperature for the meat before combining.

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