Unboiling an egg? You must be yolking
There was a lot of hype about unboiling eggs last week. Yes, scientists have indeed discovered how to unboil an egg and it definitely more useful than just being a party trick. This feat would surely net the team who discovered it an Ig Nobel Prize, if it weren’t for the fact that this new technique could allow accelerated progress in cancer research.
Eggs constitute about 90% water and 10% protein. Amino acids that form the proteins bond together and capture water, giving raw eggs their gloopy appearance.
When an egg is cooked, the protein molecules unravel themselves, link up and get tangled like unspooled fishing line, turning solid as the water is forced out. In order to ‘uncook’ the egg, you need to detach the protein molecules from each other and if possible refold them to their original shape.
Hervé This, French chemist and molecular gastronomy giant (inspiration to Heston Blumenthal himself) was the first to discover a method of unboiling an egg. This guy is the closest thing we have to a mad scientist, a quick Google search is strongly advised. He found that by adding a product like sodium borohydride to a cooked egg, the egg becomes liquid within three hours as the proteins become detached. For those who want to try it at home, vitamin C also does the trick. This method changes the bonding patterns of the proteins and they don’t function or fold as they did before.
This is, however, quite different to the method recently discovered by a group of technical eggsperts at the University of California, Irvine, the University of Western Australia, and Flinders University.
They boiled an egg at 90°C for 20 minutes to make sure the proteins were tangled beyond recognition. Following this, urea (a main component of urine) was added to the cooked albumen in the hope of restoring lysozyme, a key protein in the albumen. As the urea begun to break the proteins apart, the mixture was spun at high speed in a vortex fluid device. This device (essentially a very expensive and very fancy blender) imparts a shear stress, which further untangles the amino acids.
It was found that when the lysozyme proteins where spun in this way, they stretched to the point where they snapped back into their original form, restoring 85% of their original activity through mechanical stress. The finished result unfortunately 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 fun. They wanted to unboil an egg to solve a larger question in science: How do you quickly refold an unfolded protein? Their study appeared in January in the journal ChemBioChem.
UCI have filed a patent for this technique that could allow cancer research to be carried out more easily and cheaply. Gummy proteins formed when preparing batches of proteins, such as antibodies that detect cancer, can be cleaned easily from test tubes with this new technique, making lab work easier everywhere. This will allow the cancer detecting antibodies to be formed using yeast or E.coli bacteria instead of the current expensive method which uses hamster ovary cells (the proteins in these cells are less likely to misfold). Industrial cheese makers could benefit from cost savings too as they work with bacteria and proteins – meaning cheaper cheese for the masses.
Alice Hargreaves Jones
Feature Image: Steve Zylius / UC Irvine