My book, Cooking for Geeks (O'Reilly Media, 2010), looks at the science behind what happens in the kitchen and uses recipes to illustrate the principles. Take egg whites: why do they whisk up into a foam? Here's a short excerpt on the food science, followed by a recipe for chocolate port cake. Port, not pork! Every time I say this out loud, people think I'm talking about chocolate pork cake. While that might be delicious, chocolate port cake is really, really good, and it's easy to make, too. If you're afraid of baking but want to try making a dessert for a special romantic occasion, give this a try.

Whisked egg whites are the Styrofoam of the culinary world: besides acting as space fillers in cakes, waffles, and soufflés and as "insulators" in desserts like lemon meringue pie, when overcooked, they taste about the same as Styrofoam, too. All metaphors aside though, egg whites are much more forgiving than many cooks realize. With a little attention spent on understanding the chemistry and a bit of experimentation, egg-white foams are easy to master.

The key to understanding egg whites is to understand how foams themselves work. Whisking egg whites turns them into a light, airy foam by trapping air bubbles in a mesh of denatured proteins. Since regions of the proteins that make up egg whites are hydrophobic -- literally, water-fearing -- they normally curl up and form tight little balls to avoid interacting with the water. But when whisked, those regions of the proteins are slammed against air bubbles and unfold, and as more and more proteins are knocked against an air bubble, they form a layer around the bubble and essentially trap it in the liquid, creating a foam that's stable. Oils -- especially from egg yolks or any trace oils present in the whisking bowl -- prevent egg whites from being whisked into a foam because they're also able to interact with the hydrophobic sections of the proteins. Water and sugar don't interfere with the formation of protein-based foams for the same reason.

Once the air bubbles are encapsulated by the proteins in the egg white, it takes quite a bit of effort to get them to break. Exposing the whites to any oil before whisking is a problem; even a trace amount of fat from a small amount of stray egg yolk will interfere with the creation of the foam. But once the eggs are whisked, they're much more resilient. Try this experiment: whisk an egg white to soft peaks, then add 1⁄2 teaspoon (5g) olive oil and continue to whisk. It might surprise you how long it takes before the oil starts to noticeably interact with the foam, and even then, that the foam remains mostly stable.

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For my book, Cooking for Geeks (O'Reilly Media, 2010), I interviewed food scientists, researchers, and chefs; but one of my favorite interviews was the one I did with Adam Savage, co-host of Discovery Channel's MythBusters. And yes, Adam is just as much fun and as animated in real life as you'd suspect from watching the show.

Jeff: How do you go about testing a myth?

Adam: One of the earliest things we realized on the show is that you always have to have something to compare to. We would try to come up with an answer like: is this guy dead, is this car destroyed, is this an injury? And we would be trying to compare it to an absolute value, like X number of feet fallen equals dead. The problem is the world is very spongy and nonuniform, and trying to nail down a value like that can be really difficult. So we always end up doing relative tests. We end up doing a control under regular circumstances and then we test the myth under identical circumstances, and we compare the two things. In that comparison, we get to see our results.

We did one where we were testing whether or not you could tenderize steaks with explosives. We had to figure out what tenderness is. The problem is you can give two different people each a piece of steak from the same cut compared to a piece of steak from a different cut, and they might come up with two different assessments of which one is more tender. We actually did a whole day of testing that didn't end up on film because we realized we were using the wrong parameters for assessing steak tenderness. The USDA actually has a machine for testing the tenderness of steak that measures the pounds of force it takes to punch a hole through a steak. We replicated that machine and to our great surprise, it worked exactly as it was supposed to. Coming up with something for $50 that equals the USDA testing equipment: that was thrilling!

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