Two more gems from The Best American Scientific Writing 2007, both about molecular biology being applied to something unexpected, and both from Discover Magazine.
First, molecular paleontologist Mary Schweitzer uncovers soft tissue in 65-million year-old T-rex fossils. You can imagine the huge uproar the media raised, running the gamut from whimsical (“Now we can create Jurassic Park!”) to the crazy (“Now we know the Earth is only 6000 years old!”). Craziest thing, though, is that when Schweitzer injected the tissue into lab animals their blood raised antibodies active against turkey proteins. There you have it — definitive proof that God exists, and intends for us to eat stuffed T-rex next Thanksgiving dinner. Please, NSF, fund this woman so our gastronomical dreams come true.
Speaking of which, molecular gastronomy is the next hot thing among techno-savvy chefs in Europe, and apparently, a well-funded field of scientific endeavor in France (maybe Mary Schweitzer should try to get funding from the French for potentially growing dinosaur steaks). How could you refuse a grant to these researchers, after hearing the following mouthwatering description of the coagulating proteins responsible for an egg’s texture?
when an egg cooks, its proteins first unwind and then link to form a rigidifying mesh. But not all its proteins solidify at the same temperature. Ovotransferrin, the first of the egg-white proteins to uncoil, begins to set at around 61 degrees Celsius, or 142°F. Ovalbumin, the most abundant egg-white protein, coagulates at 184°F. Yolk proteins generally fall in between, with most starting to solidify when they approach 158°F. Thus, cooking an egg at 158°F or so should achieve both a firmed-up yolk and still-tender whites, since at that low temperature only some of the egg-white proteins will have coagulated.
“Cooking eggs is really a question of temperature, not time,” says This. To make the point, he switches on a small oven, sets the thermostat at 65°C, or 149°F, takes four eggs straight from the box, and unceremoniously places them inside. “I use an oven in the lab; it’s easier. But if the oven in your kitchen is not accurate, cook eggs in plenty of water, using a good thermometer.” About an hour later—timing isn’t critical, and the eggs can stay in the oven for hours or even overnight—he retrieves the first egg and carefully shells it. “The 65-degree egg!” he announces. The egg is unlike any I’ve eaten. The white is as delicately set and smooth as custard, and the yolk is still orange and soft. It’s not hard to see why l’oeuf à soixante-cinq degrés is becoming the rage with chefs in France. (Salmonella can’t survive more than a few minutes at 60°C, or 140°F, so a 65-degree egg cooked for an hour should be quite safe.)
["Cooking for Eggheads" by Patricia Gadsby]
Did you know that even though one egg white can only yield half a pint of meringue, simply by adding water you can extend this limit several-fold? This is because the egg-white proteins hold air bubbles in a matrix containing water molecules, and the limiting reagent normally is water. I know. I’m moving to France.