Imagine you climbed the Mount Everest! You have achieved something unbelievable and wonderful, you are unspeakably proud of yourself and you are absolutely excited and happy. But you will not be able to have one thing: a freshly hard boiled egg!Mount Everest
After you have done the unthinkable you believe anything is possible, just not boiling an egg. Why?
Well, the problem is with the height, the air pressure, and the water temperature.
Air pressure and temperature – a never-ending relationship
As higher you get as lower the air pressure becomes. And air pressure is always connected with temperature. So, if the air pressure goes down the temperature goes down, logically if the air pressure goes up the temperature goes up as well. They are always in a relationship and connection.
So due to the low air pressure on a high mountain, the water boils, with bubbles and steam, already at a low temperature. We have to remember that once the water boils it will not get hotter. So if the water boils at a specific water temperature it will stay at this temperature, no matter what.
It’s about height, air pressure and water temperature!
At sea level water boils at 100 degrees Celsius (212 degrees Fahrenheit). And with every 300 m we go up the temperature at which the water boils goes down by 1 degree Celsius.
So what’s the story with boiling eggs? Eggs have something interesting, the yolk and the egg white don’t harden at the same water temperature. The yolk needs around 65 C (149 F) to get hard and the egg white needs around 85 C (185 F) to get completely hard. So if we are at the Mount Everest, which we climbed up at the beginning, we are at 8 848 m (20 236 feet). There the water boils already at around 70 C (158 F). So the yolk might get hard but the white outside will stay glibber and we can’t enjoy our egg.credit besthomechef.com.au These eggs were not boiled at Mount Everest
What about other famous mountains? Mont Blanc at 4 810 m (15 782 feet), Mount Kilimanjaro at 5 895 m (19 341 feet) and Mount McKinley at 6 194 m (20 237 feet)?
Well, at Mont Blanc water boils at 84 C (183 F). We can boil our egg there with no problem. At Mount Kilimanjaro the water boils at 80 C (176 F) and at Mount McKinley the water boils at 79 C (174 F). There we might have a problem with boiling the egg white. But maybe, if we boil the egg long enough, we will be successful there as well. But once we are above 7 000 m (22 966 feet) no eggs can be boiled anymore.
And do you know what a pressure cooker has to do with all I mentioned above? Well, in a pressure cooker you get the pressure really high which allows the temperature to be above 100 Celsius (212 Fahrenheit). This speeds up cooking.