Cooking for Geeks: Real Science, Great Hacks, and Good Food (72 page)

Since heat is a form of energy (heat = kinetic energy of molecules in a system), adding energy to a system can cause it to heat up, which is why a hot dog gets hot when electricity runs through it. (Hot dogs happen to be made of materials — proteins, fats, a little bit of salt — that are conductive enough for this to work.)

But the potential for killing yourself on a live wire is high enough that it’s not even funny to joke about doing it. If you really want to electrocute your dogs, search
http://eBay.com
for “Presto Hotdogger.”

PHOTOS OF ELECTROCUTED HOT DOG USED BY PERMISSION OF WINDELL OSKAY

Visit
http://www.evilmadscientist.com/article.php?story=hotdogs
for more information.

P.S. LEDs light up when “plugged in” to a hot dog!

You too can make an
Apple
apple pie. Lenore and Windell used their laser cutter and a square springform pan, but with care, you can use a knife to cut the logo and a square glass pan to bake the pie. (If you’re not a purist shooting for an edible replica of a Mac Mini or Apple TV, a standard round pie will taste just as good.) For details, see
http://www.evilmadscientist.com/article.php?story=ApplePie
.

PHOTOS OF APPLE PIE USED BY PERMISSION OF LENORE EDMAN

Prepare six ramekins for baking by placing them in a large glass baking dish; set aside. Preheat oven to 325°F / 160°C.

In a bowl, separate out five large egg yolks, saving the egg whites for some other dish (see the section on egg whites in
Egg Whites
in
Chapter 5
for suggestions). Whisk the egg yolks until light and frothy; set bowl aside.

In a saucepan, measure out:

Heavy cream and whipping cream are essentially the same thing in the United States. Heavy cream usually has a slightly higher percentage of fat while whipping cream typically has a stabilizer such as carrageenan added, but you can usually use either one regardless of what is called for.

Cut a vanilla bean lengthwise and use the edge of a spoon to scrape out the seeds. Add both seeds and bean to saucepan. Set the burner to medium heat and cook the cream, sugar, and vanilla for 10 minutes, stirring continuously. Meanwhile, in a separate pot, bring to a boil enough water to partially fill the glass baking dish holding the ramekins.

After the cream mixture has been cooked for 10 minutes, fetch out the vanilla bean and discard it. Strain the mixture through a ~400 micron filter (cheesecloth works fine) into a measuring cup or other container that’s easy to pour from.

Set the bowl with the egg yolks on the counter, where you can whisk the yolks with one hand and hold the saucepan with the other. Slowly drizzle the hot cream mixture into the egg yolks, whisking the entire time to prevent the hot cream from cooking the egg yolks. Too slow is okay; too fast, and you’ll end up with scrambled eggs. (Sweet, tasty scrambled eggs, to be sure.)

Ladle the mixture into the six ramekins, taking care to not transfer any foam that you may have whisked up. (The foam will float and set on top of the brûlée.) Add the boiling water into the baking dish — enough to reach halfway up the sides of the ramekins — and transfer to oven.

Bake until the centers of the custards jiggle just a little when shaken, about 30 to 35 minutes. They should reach an internal temperature of 180°F / 82°C. Remove ramekins from baking dish and chill in fridge until cold, about three hours. (You can store them longer, of course.)

You can create a quick work surface for blowtorching by flipping a cookie sheet upside down and setting the ramekins on top.

Once cold, sprinkle a thin coating of sugar over the top of the custard. Using a blowtorch, melt and caramelize the sugar, sweeping the flame slowly across the surface until you’re happy with the color and appearance. Keep in mind that darker sugar will be more bitter; also make sure to at least melt all of the sugar, as otherwise the granulated, unmelted sugar will give an odd mouth-feel.

Transfer ramekins to fridge and store for 10 minutes to allow the sugar to cool; then serve. You can hold the torched brûlée for up to an hour before the sugary crust begins to get soggy.

Note

Charcoal or wood grill method.
This is by far the easiest method. Grills fueled by charcoal or wood get hot, easily up into the 800°F / 425°C temperature range. (Propane grills tend to run cooler, even though propane itself technically burns hotter.)

Place a pizza stone on top of the grill and light the fire. Once the grill is good and hot, use a pizza peel (a piece of cardboard works just as well) to transfer the pizza with toppings onto the grill. Depending upon the size of your grill and the size of your pizza, you might be able to cook the pizza directly on top of the grill, sans stone — give both a try!

Superhot cast iron pan method.
What if getting a grill isn’t an option for you, as is the case for many apartment dwellers? There are still a few ways left to get up to sufficiently hot temperatures. While most consumer ovens reach only 550°F / 290°C, both the oven’s broiler and the stovetop can reach higher temperatures. Leave an empty cast iron pan on a burner at full throttle and it’ll reach 650°F / 340°C in 5 or 10 minutes. And the infrared radiation from a broiler is even hotter.

Preheat oven to 550°F / 290°C, or as hot as it goes.

Superheated cast iron under broiler.

Heat up cast iron pan on stovetop at maximum heat for at least five minutes.

Place cast iron pan upside down in the oven under a broiler set to high and par-bake the pizza dough until it just begins to brown, about one to two minutes.

Transfer dough to cutting board and add sauce and toppings. Transfer back to cast iron pan and bake until toppings are melted and browned as desired.

If you don’t have a broiler, you can try a doubled-up cast iron pan approach:

Doubled-up cast iron.

Heat up two cast iron pans on maximum heat.

Par-bake the dough, flip it onto a cutting board, add toppings, and return it to the hot cast iron pan.

Cover the first cast iron pan with the second one, preferably using a larger pan so that it doesn’t touch the pizza toppings.

Cleaning cycle method (a.k.a. “oven overclocking”).
As we’ve discussed, one of the key variables for good thin-crust pizza is an extremely hot oven. Consumer ovens just don’t get hot enough; 550°F / 290°C is still a good 150–200°F / 80–110°C away from where the “real” thin-crust pizzas are cooked. If only there were a way to hack an oven to get it that hot! It turns out that there is, but it’s dangerous, voids your warranty, and, given that the alternative ways of getting this kind of heat are far, far easier, is really not worth doing. Still, for the sake of my readers, I tried this method, conceived by Jeff Varasano. (See the interview with him in
Jeff Varasano on Pizza
for details.)

Ovens get a lot hotter — a lot, lot hotter — when they run in the cleaning cycle. The problem is that consumer ovens mechanically lock the door, preventing you from slipping a pizza in and out at those temperatures, and leaving a pizza in for the entire cleaning cycle will result in a most unpleasant burnt taste, to say the least.

Cut or remove the lock, however, and ta-da! You’ve got a superheated oven. After a bit more fiddling and testing, I had an oven that I measured at over 1,000°F / 540°C. The first pizza we tried took a blistering
45 seconds
to cook, with the bottom of the crust perfectly crisped and the toppings bubbling and melted.

However, the middle of the pizza — the top portion of the dough and the bottom portions of the sauce — never had a chance to cook, so the 1,000°F / 540°C pizza wasn’t quite right (too hot). Another attempt at around 600°F / 315°C resulted in the opposite outcome: the pizza was good, but it didn’t capture the magic of the crispy thin crust and toasty-brown toppings (too cold). Around 750–800°F / 400–425°C, however, we started getting pizzas that were darn good (just right).

Ovens aren’t designed to have their doors opened when running in the cleaning cycle. Honestly, I don’t recommend this approach. I broke the glass in my oven door and had to “upgrade” it, although it is cool to have bragging rights to an oven sporting a piece of PyroCeram, the same stuff the military used for missile nose cones in the 1950s.

There’s also the issue of how hot the surrounding countertop and cabinetry can get. Commercial stoves are designed for these sorts of temperatures and as a result require a large air gap between the appliance and any combustible materials. Given that an upside-down cast iron pan under a broiler or a wood-fired grill turn out delicious flat-crust pizzas, I’m afraid I have to recommend that you skip the oven overclocking, even if it is fun.

PHOTO USED BY PERMISSION OF NATHAN MYHRVOLD

Nathan Myhrvold, formerly CTO of Microsoft, is among many things an avid cook. He has been working on a book covering the techniques of modernist cuisine.

Tell me about your background with food and how you came to be so interested in it.

I’ve been interested in food as long as I’ve been alive. When I was nine years old, I announced to my mother I was going to cook Thanksgiving dinner. I went to the library, got a bunch of cookbooks, and I did. Amazingly, she let me do it, and even more amazing, it worked out!

In 1995, while I was working at Microsoft as a Senior Vice President, I decided that I wanted to go to cooking school. I took a leave of absence and went to a school in France,
L’école de la Varenne
. I went through an intensive professional program. After retiring from Microsoft, I started my own little company, but I’d been interested in food and so decided to write a book.

There were lots of big, thick books on cooking, teaching you how to do classical cooking, but there was no modern technique within those books; they were all about the techniques of the past. I got the notion that there really was an opportunity to write a book about modernist cuisine — something that would be encyclopedic for the techniques of modern cuisine.

If I didn’t do it, it’s not clear that anyone else would, at least not for a very long time. I decided that this was my way to make a contribution to the food world. I could create a book many years sooner than anybody else because of the time, energy, and money involved. It could do something unique in terms of bridging the gap between the understanding of science and the practice of cooking in an accessible way.

What’s your definition of modern cooking? The term that would come to many people would be molecular gastronomy.

I deliberately don’t use that name. The term that I’m using is
modernist cooking
. I call it modernist because it’s analogous to what modernist architecture and modern art did in that it is a somewhat self-conscious attempt to break with the past. It has all of the intellectual hallmarks of modernism.

That happened 100 or 50 years ago in art and architecture but not in cooking. There are chefs who take offense to it if you call it
molecular gastronomy
. It’s not a terrible name per se, but it means so many different things to different people. Modernist is a more inclusive term.

Can you give me an example of something that’s surprised you in studying these techniques?

There’s a cooking technique called
confit
that means “preserved” in French. You cook the meat in oil or fat at a relatively low temperature for a long period of time, like 8 or 12 hours. Any chef would tell you that confit is a cooking technique that involves cooking in fat, which has a characteristic effect on the meat.

One day we were discussing this, and I said, “How can this possibly work? How can cooking meat in oil actually change the meat? That makes no sense to me at all. The molecules are actually too big to penetrate into the meat. It’s got to be on the outside and so on and so forth.”

So we did a bunch of experiments, and it doesn’t really have the effect that you would think. If you steam meat without any oil and you put oil in at the end, you can’t actually tell the difference.

Presumably you can’t do it just in a water bath with no fat.

We did that, too. You can’t tell the difference! You can tell the difference if you cook it at a different temperature or for a different period of time. But if you’re cooking at the same temperature and time, whether it’s sous vide or steamed or cooked confit, you really can’t tell the difference afterward. That was a big shock to us.

There’s a bunch of other things that have been quite surprising in determining how techniques work. People will frequently drop meat into ice water to stop the cooking. It’s called
shocking
.

Suppose you’re cooking a big roast or something that’s got some thickness to it. A lot of books will say take it out and then plunge it in ice water to really stop the cooking. It doesn’t work at all! The temperature at the core of the meat will not be affected by you dumping it in ice. You will cool the whole thing by dumping it in ice water, but it’s not actually going to affect the maximum temperature the core reaches.

Heat and cold “travel” at the same speed. It’s not exactly correct, but if you think about a wave of heat going from the outside in, shocking it is going to put a wave of cold, a “negative” wave of heat. But it doesn’t go faster, and the hot wave that started before will hit the center before the cold wave does.

Wow, that makes a lot of sense. Are there other examples of processes that you’ve discovered that apply to the way that most people cook on a day-to-day basis?

One of the things that we’ve spent a bunch of time on in the book is explaining the role of humidity in cooking. Most food is wet. When you heat wet things, they give off water and that takes a tremendous amount of energy to do. The rate at which the water evaporates depends on what the humidity is.

If you cook something in Aspen in the winter when the humidity outside is really low, and you cook that same thing in Miami in the summer when the humidity is very high, you actually get radically different results. It can make a 10 degree difference in the temperature that the food is experiencing, particularly at the onset.

We went through a whole bunch of examples like this. It turns out that humidity is a huge factor in how cooking actually happens. A convection steam oven controls the humidity, and that’s its huge advantage. One of the advantages of sous vide is you seal the food up in a plastic bag where there is no variation in humidity. But if you’re cooking out in the open air, humidity actually makes a big difference. That’s one of the reasons that people don’t have their recipes turn out quite like they thought.

Is that something that’s important to absolutely every cook in America? I can’t tell you that it is. I think it’s kind of cool; it certainly will matter to professional chefs. Every chef has had the situation where they try the recipe in the book and it doesn’t work, or the chef travels and the food doesn’t quite turn out right. This is one of the reasons. If you’re not controlling humidity, it’s a free variable, and it will make a big difference.

People don’t generally understand how much energy it takes to boil water. This dramatically affects cooking. If you just look at the latent heat of vaporization of water, it takes four joules of energy to move a gram of water one degree Celsius, 400 joules to take it from just above freezing up to the edge of boiling, and 2,257 joules to boil it. That’s why steam engines work. All kinds of things are driven off this one fact.

How do you think what you’ve learned will change the approaches of chefs and amateur cooking enthusiasts?

What we’re hoping to do is enable chefs to use a broad range of techniques to make the kinds of food they want to make. Right now there is a set of chefs who are using these very modern techniques. There are a lot of others who don’t.

It’s very hard to learn all of this stuff. We’re hoping that we can give chefs and amateurs an accessible way to understand how it works. If we can do that, I think that we can really make a difference in how folks cook. That’s not world peace; it’s not solving global warming or something like that, but it is something that, within the cooking world, I think people are going to find tremendously exciting and empowering.

Any parting words of wisdom that you would give somebody learning to cook?

Learning to cook is a wonderful thing to do and I highly recommend it to folks. The message in a lot of recipes is, “Don’t worry about how it works, just do this, this, and this, and the right thing will happen.”

When it works, that’s okay. When it doesn’t work, you don’t really know why. I always feel cheated when that’s the case. I want to find out why. I’m still learning how to cook. I think even the best chefs in the world are still learning how to cook, and it’s that learning and that exploration that makes it interesting.