Heston Blumenthal's Perfect Steak
I was watching an episode of In Search of Perfection about cooking a "perfect" steak and it left me confused.
Heston started things off by blowtorching the exterior a two-bone big slab of meat. He then popped it into a 120F oven for 24 hours. After removing it and letting it cool for a few more hours, he cut the meat off of the rib bones. And this is when he did something that baffled me. He lopped off the blowtorched exteriors. Huh? In the online recipe, it's referred to as "[trimming] off any overly charcoaled exterior." He then cuts the meat into two steaks and proceeds to sear them in a screaming hot cast iron pan like you would normally do.
But what the heck was the point of blowtorching the exterior? When he pulled out the blowtorch I thought "what a great way of browning a steak without cooking the inside!" And then just like that, he goes and cuts it off. So does that blowtorched exterior actually impart some flavor deep into the meat while it's slow roasting in the oven? Is it just to prevent bacterial growth on the surface? Someone please explain this to me!
Here's info about the steak:
The blowtorched exterior is primarily for safety - 120 F is not high enough to effectively kill bacteria and the steak will take a good while even getting to that temperature in a dry oven. Since most bacteria in beef would be on the surface of the meat, the blowtorch is a way to make sure you don't have active growth as the steaks come up to heat. Once you blowtorch the meat, be very careful in handling it, since introducing staph bacteria (common to many people's nose/mouth/hands) again now could defeat the whole purpose. I use similar tricks to keep meat safe for a long, low temperature sous vide cooking.
The additional theory is that blowtorching creates a maillard reaction that flavors the meat, and given the long cooking time, some of those deeper, browned flavors may start to leech inward and flavor the rest of the steak. Whether this is effectively true after you've cut off and discarded the outside, I cannot say as I haven't actually made steaks in the Heston way.
edit: Also, if you haven't tried browning meat with a blowtorch before, you may be surprised at the difficulty of creating the kind of evenly-brown exterior you're used to enjoying on meats. There is a tendency to get many small black/charred muscle fibers without as much of a browning effect as you get on a grill or hot pan. A little oil can help even it out a bit, but the technique seems to work best for things that already have a high-fat content in them, like foie gras. I mostly rely on other very high-heat methods of creating a browned crust on foods I don't want to overcook.
Heston may be be lopping off the ends of his blowtorched meat in part because the blowtorched exterior is not that appetizing.
The upside of a blowtorch is that it makes for minimal cooking of anything beneath the surface - you're exposing small areas of the meat to far higher temperatures than you could create in a pan for a very short time before re-exposing them to room temperature air, creating very little shortening of muscle fibers (and water loss) or deactivation of enzymes (I'll take Blumenthal's word for it that enzymes are important here). The more brief the exposure and the hotter the source, the less the inside of the meat will cook.
In practice though, I've had fine results with other methods. A dry pan alone will have the tendency to miss spots and crevices in the meat during a very brief sear thus opening the door for bacteria. But I've submerged proteins (in vacuum bags) into boiling water briefly without any noticeable cooking of the interior. In another chowhound thread, another poster mentioned dipping a big chunk of meat into a deep fryer for 30 seconds or so with no problems with overcooking - I think it might have been this very recipe where he did it. I'm sure a fairly hot sauté (generous on the oil, make sure to get the edges) would work with a chunk of meat this big. I suspect Heston is just making a point of refusing to compromise in this recipe and picking the method that has the least effect below the surface while other methods would work too.
Quote, me: 'Also, if you haven't tried browning meat with a blowtorch before, you may be surprised at the difficulty of creating the kind of evenly-brown exterior you're used to enjoying on meats.'
Update: I take back some of the negative things I wrote about using a blowtorch. Posting this the other day got me thinking. As I said above, I've found the blowtorch to be ill-suited to creating a nice brown crust on meats. But was this my fault? I'd seen photos of blowtorched meat that look decent. Dry heat, dry meat - this should work. It bugged me.
So I tried again today. With much better results. Turns out that I was being too impatient and trying to brown each spot of meat before moving on. I was holding the blowtorch in one spot for too long, waiting for that spot to brown. That always resulted in the problems I described above.
This time, I cooked a steak sous vide. I dried the meat (as I always have previously), brushed the surface with canola oil, fired up the blowtorch and got started.
This time, I kept the torch moving and passed it repeatedly around the surface of the meat for a couple minutes. I got a much nicer maillard reaction on the meat with much less charring of individual muscle fibers. Not the same result as you'd get on a grill or hot pan, but a lot more useful nonetheless.
Sorry for misleading anyone.