[timtadh]

I don't know a lot about sous-vide, I am more of a wood fire and smoking kinda person, but what would prevent you from using a stainless steel canister? That would eliminate the risks from plastic. Perhaps, a ceramic would also work?

[tptacek]

You still need to put the food in something that keeps it out of direct contact with the water while not leaving enough space for air to insulate the food.

[timtadh]

I see. So a hard sided container won't trasfer heat properly? Sounds like I need to talk to a friend in polymers to really get a grasp on the right approach because I can't really think of a non-polymer material that would meet the flexibility requirement.

In general it seems like sous-vide would result in food similiar to a braise but without the browny bits and the pan sauce? (saying it that way makes it sound unappetising but I understand it is quiet nice) That said, I think while it doesn't have the asthetic of a wood fired smoker, a device like the op's could replace the slow cooker.

[tptacek]

Noooooooo. Food is not similar to a braise. The point of low-temp cooking (sous vide is low temp under a hard vacuum) is that the cook locks in a perfect temperature for the food and the water bath never exceeds that temperature. In practice, you aim never to exceed the temperature at which the protein expels all the water from the food; think: absolutely perfectly cooked steak --- or, more magically, think a short rib, cooked to the doneness of a perfect steak, but with all the collagen converted to gelatin as if in a braise; it's the best of both worlds. Because a short rib cooked to the temperature of a perfect steak in an oven would be tough as nails, it's something you can really only achieve in a water bath.

There are other tricks too; you can simultaneously cook a dozen eggs to perfect running or "walking" yolk, without paying any attention; you can cook veg to a temperature between the breakdown of pectin and cellulose; you can heat-temper carnaroli or arborio rice and set the starches, so that you can make bulletproof risotto in a pan by dumping all the liquid in at once.

It's a pretty nifty tool.

[thenomad]

I've been cooking sous-vide for years and somehow missed the risotto trick - thanks for that!

It's worth noting that sous-vide can also cook meats that are somewhere between "a right pain" and "almost impossible" to cook another way. In particular, sous-vide and a bit of time transforms mutton into one of the tastiest, cheapest meals imaginable. I had real trouble going back to lamb after a few months of sous-vide mutton.

[timtadh]

Sounds neat I will definitely do some research on it. Smoking is a similar process but without a fancy rig you can't get control very precise (+/- 30°f is what I can achieve over an 8 hour smoke. pros can do much better). The idea is similar, low temperature forea long time, until the meat hits the desired temperature.

[ahh]

Can you elaborate a bit on the risotto? I've never gotten a clear answer on how that's supposed to work.

[tptacek]

The premise is amylopectin retrogradation. Heat a starch to the point where it breaks up and liberates its network of amylopectin. Cool it, and the starch crystallizes in a much stronger structure. Heat it again, or (in the case of, say, potatoes) beat the hell out of them in a blender, and they'll retain their structure; they become somewhat bulletproof.

Retrograded arborio is stable enough that you can dump boiling liquid onto it, stir it, reduce the liquid, and end up with perfect risotto --- rather than carefully tempering the rice with small amounts of slowly stirred liquid. Hence: 7 minute risotto.

It turns out you can also simply hydrate risotto rice (soak it in cold liquid for a couple hours) and do the same thing to it, but it doesn't hold long term the way the retrograded risotto does.

These ideas are due to Ideas in Food, a really amazing blog. The authors have published a couple of books; their first (I think it's just "Ideas In Food") is one of my favorite cooking books.