Which torch to buy for finishing sous vide meat? Butane or propane?

I use Propane all the time. There are several factors as to why:

1. It is cheap, about 1/4 the price of butane.
2. It’s more readily available. You can buy a propane torch at many different stores for very cheap.
3. The torches typically put out a lot more heat. I’ve used both propane and butane, mostly for crème brulee, but other food as well. The butane torches put out such a focused small area of heat, that it would get uneven burning. Whereas with Propane, they often put out a much larger area of heat, making it easier to caramelize across the surface evenly.

As for the concern of it imparting propane flavor, I have had that happen, once, but I’ve also had that happen with butane. It’s all about flow control. If you have the dial turned up too high and it’s spewing out massive amounts of propane, plus hold the flame too close to the food, you MIGHT get then hint of propane. But if you have the torched dialed in to the proper settings, you really can’t beat the ease and convenience of “energy-efficient clean-burning propane gas”

I agree with Nick's answer and also use a propane torch. I'll add, don't get a "cooking" torch (i.e. one designed specifically for the kitchen). They're expensive, have a smaller flame, and use a small gas container. It would be a huge pain to try and use for something large (like flank steak, a sous vide favorite). Instead, get a plumbers torch at Home Depot. I use a Bernzomatic which just screws a nozzle on to a blue gas cylinder. Much better and way cheaper than anything you'd get at Williams Sonoma.

All that said, I don't think that the propane torch does nearly as good a job as a screaming hot grill or pan (screaming be the operative word in either case as you want to sear the outside without cooking the inside). But a grill takes time and a pan that's hot enough kicks up a ton of splatter. The torch is definitely the most convenient, but unfortunately, it's not a silver bullet.

Dave Arnold's Searzall was invented specifically for use with sous vide cooking, and for the purpose of eliminating "torch taste." I have one and use it frequently. Having said that, depending on the cut of meat, sometimes the best tool for the job is a blistering hot cast iron pan. In the picture below, I am finishing a sous vide burger with the Searzall. ...uses propane...and is cool as hell.

Check out this discussion here: http://forum.chefsteps.com/discussion/13/mapp-gas-vs-propane-torches#latest

For sous-vide cooking your going to want the hottest flame you can get (and are comfortable with). Those tiny creme brulee torches are cute but your food will be cold by the time you put a decent sear on it (trust me i've tried). Most people go with a torch adapter that can be screwed on to butane canisters such as this http://amzn.com/B0027HO3XO

WOW! I went out and bought the $29.99 Greenwood Propane Torch from Harbor Freight. I connected it to a 20 lb propane tank and lit it. STAND BACK! That's like searing with a jet engine! Might be a little over-kill but it blasts an almost invisible blue flame. It will definitely sear a steak quick. However, I have read that the fuel taste comes from too hot of a flame and not from unburnt fuel.

I tested it on two steaks. It will certainly sear steaks quickly. Less than 5 seconds on each side. When you pull the trigger it is very loud and sounds like a fighter jet that turned on its' after-burners! It's way too hot to use indoors. I heated the grill, threw the steaks on and immediately blasted, flipped and blasted the other side. We didn't taste a fuel taste and the steaks had a very nice sealing crust.

I have two propane torches. One is the Bernzomatic-type handheld, and the other is a 500,000 BTU weed burner monster that I call "Mr. Flamethrower". I got mine at Harbor Freight for $20, and it connects to a 20lb tank. The flame is adjustable. I use them both.

I agree that the butane torches are too small, but they work fine otherwise and don't seem to add any taste of their own. They're good for small strips of beef for sushi.

My ideal torch would be either alcohol, from an old-fashioned blow torch, or even better a hydrogen flame. Hydrogen flames are very hot and burn so cleanly that the flame is invisible. Controlling an invisible flame might be an issue though.