A few notes on the physics of egg-boiling.

[samvara]

There is some debate as to whether it is possible to soft-boil the perfect egg. Let me put your mind at rest; it is indeed possible. Not only that you can have some fun working out how to go about it. The perfect soft-boiled egg has a firm, tender and completely cooked white with a soft, runny yolk.

Some facts:

Egg white is composed of a lot of long organic molecules, if you cook the white quickly; they form a rubbery spaghetti heap. If you cook the white slowly, the molecules line up and the cooked white is soft and tender. This stops you concentrating on the texture and leaves you able to focus on the taste. The ideal soft-boiled egg should be cooked slowly.

Egg white cooks at 62C while egg yolk cooks at 68C. The ideal soft-boiled egg should be prepared at 65C.

There are a number of ways to achieve this: 

CONTROL TIME

Some people think you should be able to produce the perfect 3 minute egg without considering that conditions vary considerably between kitchens. 

What size eggs do you buy? Larger eggs take longer to cook

Where do you store your eggs? Colder eggs take longer to cook

What are you cooking with? Electric stoves take time to warm up

Where do you get your water? Hot water comes to the boil faster than cold water.

What do you do to the egg after you've boiled it? Dunking the egg in cold water stops it from continuing to cook in the shell.¹

These are all factors that can be addressed by changing your timer. Work out how long it takes with your prefered implements/system and it's just a matter of getting that egg out at exactly the right time.

¹ The shell also separates from the skin making them easier to peel.

CONTROL TEMPERATURE

Bake your egg in an accurate oven set to 65C rather than boiling it.

Acquire a laboratory hotplate in the correct temperature range.

Cook on a stove-top with a thermometer at 65C and don’t boil the water.

Arrange for water to boil at 65C². 

Please note eggs do not cook nearly as quickly at 65C. 

²As it happens, water only boils at 100C at sea level because of the weight of all that air pushing down on it. If you go higher, where there is less air, water boils at lower temperatures. Some dodgy mathematics says the following conditions apply:

Elevation: 28 300 feet = 8,625.84 meters
Current Barometric Pressure: 25.9 mmHg
Boiling Point Estimate: 149 degree Fahrenheit = 65 degree Celsius

This means that the perfect soft-boiled egg is in sight at 8.6km. Alas, you will need to take oxygen as it takes a good few minutes to boil an egg at 65C and you’ll have less than that conscious.

"The first men to reach 30,000 feet (9,144 meters) did not know what they were facing. It is now known that at an altitude of only 10,000 feet (3,048 meters), the brain loses 10 percent of the oxygen it needs and judgment begins to falter. At 18,000 feet (5,486 feet), there is a 30 percent decrease in oxygen to the brain, and a person can lose consciousness in 30 minutes. At 30,000 feet (9,144 meters), loss of consciousness occurs in less."

Comments

[strangedave.livejournal.com]

The books of Harold McGee are highly recommended for kitchen science.

[black-samvara.livejournal.com]

Ta. This is a kind of follow up to a conversation I had years ago with someone who swore that his egg boiling time was longer than his mother's because of genetically engineered chickens designed to lay slower boiling eggs.

[tiger-75.livejournal.com]

I think the footnote regarding oxygen depletion, faltering judgement coupling together with egg boiling says it all. Have you been climbing up big hills again?

x
;-)

[black-samvara.livejournal.com]

Jogging, and doing situps - silly me.

I talked about egg boiling at Fandomedia and just wanted a convenient repository of what I'd said all prettied up.

[tiger-75.livejournal.com]

Wish I was well enough to jog and do sit ups. I would kill to go to training...

I will beat the bug (chants to self)

[black-samvara.livejournal.com]

Get better! [thinks healthy thoughts]

It was a short jog and only 30 situps - am scarily unfit right now.

[ironed_orchid]

I just love this. So geeky and completely and utterly useful. Now, if only I could poach the perfect egg every time, well, then I'd be better at poaching eggs.

[black-samvara.livejournal.com]

[hug] Thanks!

I'm not too clear on the science of egg poaching, I do them in a small non-stick pan with a dash of cider vinegar. Mostly the trick seem sto be getting them out at exactly the right time.

[divineway.livejournal.com]

excuse me, while I'm a total geek for stuff like this, the montion of boiled eggs made think of Tigh's eye.

Would that constitute an obsession with BSG?

[black-samvara.livejournal.com]

The fact that Tigh thought of boiled eggs disturbs me!

[haircaspian.livejournal.com]

Work out how long it takes with your prefered implements/system and it's just a matter of getting that egg out at exactly the right time.

I'm assuming you do this by trial and error.

What do you do with the failed experiments? In particular, when they're undercooked. I usually put them back in the water even though they're open, but I'm not too happy with the results.

[black-samvara.livejournal.com]

I had to stop and think about this, I tend to overcook and work my way down so my eggs tend to be hard boiled rather than runny.

Also I have a dog/vacuum cleaner.