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How Unboiled Eggs Could Help Fight Food Waste

Steve Kudlacek is an undergraduate at the University of California, Irvine who helped Professor Greg Weiss develop a way to unboil an egg.
Steve Zylius
UC Irvine Communications
Steve Kudlacek is an undergraduate at the University of California, Irvine who helped Professor Greg Weiss develop a way to unboil an egg.

Any chef can whip up an egg over-easy, fried or poached. But what about unboiled?

Leave that to a group of scientific eggsperts at the University of California, Irvine, the University of Western Australia and Flinders University. Recently, they figured out how take an egg from a fresh to a boiled back to an unboiled state.

If you were wondering, the unboiled result doesn't much resemble the original egg at all.

"It's extremely unimpressive," says chemist Greg Weiss at the University of California, Irvine. Like, "here's the tube with some liquid on the bottom."

But Weiss and his team weren't doing this just for kicks. They wanted to unboil an egg to solve a larger question in science: How do you refold an unfolded protein? Their study appeared in January in the journal ChemBioChem.

When an egg is boiled, or cooked for any delicious purpose, the proteins inside, which are folded like complex origami into precise 3D shapes, begin to unfold

As proteins unfold, "they start sticking to each other and getting tangled like unspooled fishing line," says Weiss. The boiled egg turns solid as the proteins mesh with other proteins, and force water out.

Unboiling the egg essentially means refolding the proteins into their original shape. And that's a big deal for science – it's estimated the pharmaceutical, environmental and food industries, among others could save $160 billion a year by refolding tangled proteins.

Correctly folded proteins in the form of enzymes are critical in transforming milk into cheese, flour and yeast into bread and grape juice into wine. But when food companies make or get them, some may not be folded properly. And those unfolded proteins are like broken tools, unable to speed up the chemical reactions that turn raw ingredients into these prized foods.

That means that producers have to throw away or tediously separate the faulty enzymes out in a four-day process called dialysis.

The researchers knew that this is a problem that affects not just food producers, but also cancer researchers who struggle with unfolded proteins in some treatments.

So how exactly did Weiss and his team go about refolding the proteins? To unboil the boiled egg, the team first separated yolks from hen eggs using the Julia Child method. Then they boiled the whites for 20 minutes at 194 degrees Fahrenheit (90 degrees Celsius).

The researchers then dissolved the egg whites with a chemical called urea, put them in a test tube, and spun them hard and fast in what's essentially a very expensive and very fancy blender.

Then they looked at a particular protein: lysozyme, an enzyme in the egg white (which also happens to be found in tears).

What they found was that when the lysozyme proteins were spun at high speed, they actually stretched and stretched until they snapped back into their original shape. In fact, the mechanical stress restored the proteins back to about 85 percent of their original activity.

But don't expect the findings to get the food industry excited just yet. Not many food manufacturers need this refolding technique right now, says Srinivasan Damodaran, a food scientist at the University of Wisconsin. The method is more relevant for cancer researchers, who make proteins that may need to be refolded for research, says Weiss.

Other researchers are more hopeful, suggesting if there's less waste from misfolded enzymes, perhaps the food producers will be able to try out new proteins. "Assuming the results can be scaled-up (not always a small task), this could potentially result in savings and new types of enzymes available to both home cooks and larger food producers," Gavin Sacks, a food scientist at Cornell University told The Salt via email.

But Weiss says, for now, "there's no impact on your dinner."

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Corrected: February 2, 2015 at 9:00 PM PST
The photo caption in an earlier version incorrectly identified University of California, Irvine undergraduate Steve Kudlacek as chemist Greg Weiss.
Alison Bruzek