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You may remember a few months back when I was doing some serious testing on the Sous Vide Supreme. During the course of that testing, I cooked a few burgers that absolutely blew my mind. We're talking burgers that oozed juices for nearly a minute after biting into them. Burgers that were thick, juicy, and perfectly medium rare from edge to edge with crisp brown crusts. We're talking nearly perfect burgers here.
N.B. For those of you who are still unfamiliar with the technique of cooking sous-vide, see here
Well since then, I've taken the time to try and push those burgers a little bit closer towards getting rid of the "nearly." Here's what I've discovered.
Cooking a thin burger is simple. Just get your pan ripping hot, use fresh beef, and it's tough to go wrong. With a thin burger, it's all about the crust and deep brown flavors, so hitting that perfect medium rare is not that big of a deal. Cooking big fat burgers is when you run into some trouble, and it usually goes like this:
Now I admit, this particular photo is a pretty extreme case, but even in the best of times, a big fat burger has the problem of overcooking around the outside before the center gets a chance to finish (for a great example of this, try the burgers at the Corner Bistro). Of course, for anyone whose read the Sous Vide Steak Primer, this is nothing new. It happens with pretty much any large piece of meat cooked at a high temperature.
We've already talked about how flipping repeatedly while cooking and how starting a fat burger in a low oven can help with this problem, but cooking the burger sous-vide offers advantages in that it's totally foolproof, creates an even more evenly cooked center, and also affords you the option of flavoring your meat (as we'll discuss later on).
That said, there are still a few choices to make when it comes to cooking a burger sous-vide.
That's My Bag, Baby!
Cooking sous-vide starts by placing the food in a plastic bag. While normally the goal is to remove as much air as possible, requiring the use of a vacuum pump, with burgers, using a pump that's too powerful can lead to to problems.
The burger on the left was sealed using a Food Saver brand vacuum sealer, while the burger on the right was sealed using the dip-in-water technique—an ingeniously simple method which was explained to me by Dave Arnold at the French Culinary Institute a few months back. Essentially, you place your food in a plastic zipper-lock bag, close up all but the very edge of the seal, then slowly dip it into water, pressing the air out as you go, keeping the sealed corner out of the water for as long as possible. Once your food is almost fully submerged, you zip up the last bit just before it reaches the water level. You're left with food in a nearly airless bag, but with very little compression.
That little bit of extra compression may not seem like a big deal, but look what happens when you cook the suckers:
See the difference in texture? While the burger on the right keeps a nice puck shape and has a loosely textured interior, the compressed burgers on the left gets squished into a discus-shaped saucer, with a firm, dense texture.
It's been suggested by several sources that browning the burger before sealing it will help those browned flavors penetrate into the meat. Similar to my findings with sous vide steak, I found this to be a totally unnecessary step. Whatever extra flavor you get from the browning is completely lost, provided that you brown it properly after you get it out of the bag.
There are two basic options here, and each have their own advantages: searing in a skillet vs. deep frying.
Deep frying the burger, (as seen on Ozersky TV's "22nd Century Hamburger" segment) creates a wicked crispy crust, with the advantage that the crust forms evenly on all sides of the patty—top, bottom, and all the way around. It's also not messy, and won't smoke out your apartment the way searing can. The problem with it is that deep frying oil temperature maxes out at around 400 degrees—even lower if you consider that the temperature of the oil immediately surrounding a piece of frying food is significantly lower than the rest of the pot.
This brings us back to the same old problem with fat burgers: By the time a decent crust has formed, we're talking a good 1/8th to 1/4-inch of meat that has overcooked and turned leathery around the edges:
Pan-searing, on the other hand, does not have that problem. As long as you have a thick, heavy pan (a cast iron or carbon steel skillet will do), and let it preheat until it's really really hot, your burger will form a deep brown crust in well under 45 seconds or so, preventing that leathery skin from forming. Pan-searing also produces better flavors in the crust.
The disadvantages are that first of all, you don't get much browning around the edges of the burger, and secondly, if the photo at the top of this section proves anything, it puts a lot of smoke in the air, and makes a mess of your stovetop.
So which method wins in the end? It's all about personal preference. Deep frying produces a superior crusty texture without creating a mess in the kitchen, but pan-searing offers better flavor development and better internal texture. As I don't mind cleaning the kitchen, my vote goes towards pan-searing.
What's in the Bag
I've seen it recommended to add butter to the bag for all kinds of sous-vide recipes, and frankly, I don't get it. When added to a bag with steak, it actually decreases the steaks flavor, as many of the fat-soluble flavor compounds dissolve in the melted butter, which then gets thrown away. Same thing with the burgers. The burgers I made with butter in the bag came out with a distinct flavor disadvantage, and no gains in moisture or texture.
It's the equivalent of boiling chicken parts to extract their flavor and make a great stock, then throwing that stock away. All the flavor goes down the drain with it. Don't do it.
On the other hand, cooking burgers sous-vide offers you an opportunity to flavor burgers in a way that has never been possible before by adding aromatics directly to the bag.
Now now, I know what you're going to say: "But a burger should be beef and beef alone!," and I agree.
But my main gripe with adding shallots, garlic, herbs, or other such junk to a patty by mixing it in the traditional way is that it by necessity forces you to overwork the meat in order to evenly distribute the flavorings, irrevocably altering its structure. In addition, those ingredients pick up that telltale "steamed" flavor as they cook inside the patty. You ultimately end up with a burger that has the texture and flavor of meatloaf.
By adding the aromatics directly to the sous-vide bag, on the other hand, none of these disadvantages occur. As the burger slowly cooks in its water bath, the exterior gets gently perfumed with whatever it is you put in there with it. I tried a sliced garlic clove, parsley stems, and coriander seed. After it comes out of the bath, I discarded the spent aromatics, and seared as usual. The result is a burger with the interior texture and flavor of a regular burger, but with a distinctly and deliciously flavored outer crust. Yum
The Short Of It
So to sum up:
- Don't bother pre-searing your burger. It makes little difference to the end product.
- Don't seal your burger with a vacuum sealer. It'll compress the texture.
- Do sear or deep fry your burger, depending on how you like it. Deep fried for superior exterior texture, seared for better interior texture and better crust flavor
- Don't add butter or any other fat to the bag. All it does is dilute flavor.
- Do add aromatics to the bag if desired.
Oh, and by the way, that burgers cook fast and at a relatively low temperature make them an ideal candidate for Beer Cooler Sous-Vide. Does anyone else smell a BBQ?
Continue here for the recipe for Sous-Vide Burgers »
About the author: After graduating from MIT, J. Kenji Lopez-Alt spent many years as a chef, recipe developer, writer, and editor in Boston. He now lives in New York with his wife, where he runs a private chef business, KA Cuisine, and co-writes the blog GoodEater.org about sustainable food enjoyment.