Once the food is cooked, you cannot uncook it; soup, cake, pasta, you name it. But, perhaps, not the egg. Somehow, though, the egg has defied the rule, as scientists have shown that an egg can be unboiled to some extent.
Boiling eggs involves reactions occurring at the microscopic level, involving the egg white proteins. Scientists attempted to bring back boiled egg white proteins to their former state – a process that lasts for a few minutes only. The study was published in the journal ChemBioChem.
The purpose of the study, you ask? Well, let’s just say that a group of chemists just wanted to test the feasibility of unboiling an egg, as well as developing a new technique the application of which extends much further than just dismantling old kitchen rules. The strategy used can be extended to food production and even to research on one of the deadliest diseases, cancer.
To understand ‘how to unboil an egg’, we have to first understand the make-up of an egg. Eggs are rich in proteins, with proteins constituting 12 % of the egg white, and 16 % of the yolk. Proteins are construction from building blocks called amino acids which are arranged specifically according to the particular protein. The special pattern and arrangement of the amino acids confer on the protein its particular shape and govern its properties. Furthermore, the links bonding the molecule together are sensitive to changes in pH and temperature – that is how proteins unfold and tangle. The process where the protein is subject to changes that distort it out of its shape is called denaturation. Once denaturation occurs, the protein cannot be recycled.
Denaturation of the protein is what happens when egg whites actually turn white (from transparent) when it is being cooked.
The existing techniques of ‘saving’ proteins are time-consuming (lasting for 4 days) and expensive. So, the scientists wanted to go about this ‘problem’ of losing precious proteins.
The lead author, Gregory Weiss, stated that:
“It’s not so much that we’re interested in processing the eggs; that’s just demonstrating how powerful this process is. The real problem is that there are lots of cases of gummy proteins that you spend way too much time scraping off your test tubes, and you want some means of recovering that material.”
The scientists devised a methodology that would take only a few minutes to ‘unboil the egg’.
They began boiling egg whites for 20 minutes at 90 degrees Celcius, thereby scrambling the proteins. Then, they added urea to the mixture to restore main protein lysozyme. The urea breaks down the clumped proteins and changes the solid material into a liquid.
Next, the researchers placed the solution into a vortex fluid device to apply stress on the proteins so that they untangled and refolded back to their former state.
The results showed that eggs can, in fact, be unboiled. The strategy can now hopefully be applied in both research and industrial sectors. For instance, it can help reduce the costs of creating therapeutic antibodies which are proteins in nature.