Boiling an egg doesn’t sound like the most challenging thing in the world. Just put a kettle on the stove, leave some eggs to boil for a couple minutes — presto! But if you’re after the perfectly boiled egg that is exactly to your taste, it’s going to take more diligence because eggs can be quite complex. Luckily, one quantum physicist has devised a calculator that tells you everything you need to do, based on pluggable parameters. With Easter right around the corner, you might want to give this a try.
The egg boiling calculator
There are many reasons why boiling an egg can go awry. For one, the yolk and white inside have different compositions of fats and proteins, which cook and harden at different temperatures and rates. This is why for a soft-boiled egg, you typically have to boil at a lower temperature and for a shorter while than for a hard-boiled egg. A smaller egg has a smaller surface area than a bigger egg, so it will cook faster — another thing you ought to consider.
An egg plucked straight from the fridge and into a kettle will boil differently than an egg that is stored at room temperature. Finally, altitude is very important as it affects the boiling point of water and, hence, the quality of your desired type of boiled egg. This latter parameter is also the most overlooked among the lot, despite having a significant impact. The higher up you climb relative to the sea level, the lower atmospheric pressure becomes. A liquid boils when its internal vapor pressure is equal to the atmospheric pressure, which is why the boiling point of water is lower at higher altitudes. In the city of El Alto, Bolivia (4,150 meters altitude), it takes two and half minutes longer to make a soft-boiled egg than at sea level. On Mt. Everest, the highest peak in the world, it’s impossible to boil an egg because the boiling point is too low for the proteins to get ‘cooked‘.
Miłosz Panfil, a theoretical physicist at the University of Warsaw, worked with Omni to devise an online calculator that takes all of these parameters into account and returns the optimal boiling time. The calculator is based on a formula devised almost twenty years ago by Charles Williams, a physicist at the University of Exeter. According to Science Alert, the simplified version looks like this:
t = m * K * log(ywr * (Tegg – Twater)/(T – Twater))
Where t stands for time, m is mass, K is the thermal conductivity of the egg, T is the temperature measured at a point between the white and yolk, Tegg is the egg temperature, Twater is the water temperature and ywr is the yolk-white ratio.
“We encountered typical issues with modeling natural phenomena: you have to make your ideas meet reality. Most of the work was done and perfectly explained by Charles Williams in his old paper. We had to tweak a bit some of the parameters, but with people working at OMNI this is not a challenge. Their enthusiasm for science made it a great adventure,” Panfil told ZME Science.
“I’m kind of excited to see if other people can follow our recipe and get a perfectly boiled egg,” Panfil added.
The maximum temperature you should set for a perfect soft- and hard-boiled egg is 65°C (149°F) and 77°C (170°F), respectively. If you’re using a gas burner to boil, you might find it difficult to maintain a constant temperature. A kitchen thermometer will save you a lot of headaches if you can’t control temperature.
Another parameter that might influence the quality of a boiled egg its source. The calculator, however, does not differentiate between eggs comes from free-range or caged hens, as this would have complicated matters even further.
“The type of hen’s diet likely influences the composition of an egg and there are claims the nutritional data varies for caged and free range eggs. That being said I would not expect a large difference. In home conditions, other factors are probably more important. However, I’m far from being an expert on the biochemistry of eggs so take it with a grain a salt,” according to Panfil, who said he likes his boiled eggs, “again, with a grain of salt. And a bit of pepper. I like them in their pure form. As I’m getting older my choice shifts from soft-boiled eggs to hard-boiled ones. My wife has a strong preference for soft-boiled eggs though. I guess it keeps me younger.”