I am trying to hard boil a dozen eggs here and I boiled the water, set the eggs into the water with a slotted spoon 3 at a time. As soon as my cold eggs hit the boiling water, 5 of them cracked and started shooting whites into the water.
I know they weren’t cracked when I took them out of the carton so why did they crack immediately upon being dropped in the water? How do I avoid this in the future?
I have heard that if you add salt to the water this will not happen. I have not tested this but…
I’m guessing that the eggs were kept in the refrigerator? If so, perhaps the cold eggshells failed when they hit the boiling water beause of the temperature difference, much like a car’s frozen windshield might crack if you put boiling water on it.
I put my eggs (on the rare occasions that I eat eggs) in cold water and bring them to a boil.
Well, I have tested this, and it does work. Occasionally, I still might have one crack, but it isn’t near the crack they I normally would have gotten. I may have not used enough salt when it did happen. The salt works because it changes the temperature of when the water will boil.
John
As a footnote, I also do as another poster, and put them in the cold water first, then bring to a boil. I think dropping them in already hot boiling water only exacerbates your problem.
John
I always take the eggs I’m going to use out of the refrigerator before I’m ready to cook with them and let them warm up to room temperature. You should never cook with cold eggs. Boiled eggs, omelettes, fried eggs, etc., don’t come out right if the egg that hits the heat is cold.
There is very little risk of salmonella if the eggs have been properly stored in the back of the fridge (the coldest part) since they were brought home from the grocery and you have only warmed up the eggs you’re going to use right away.
Cooking 101:
Always place the egg in lukewarm water in the pot before placing it on the stove. Even then some eggs will crack slightly, nothing that would make a difference in the end though. acsenray has the best solution if you want perfect eggs. It’s all about cold meets hot.
I sat down at a table in a NJ restaurant with three of my friends when the waitress came over and poured us each a glass of ice water prior to taking our orders. As she walked away one of the glasses shattered spilling water and ice cubes all over the table. Pretty creepy, we were talking and suddenly the glass burst, before any of us had touched it. The best that I could figure an already stressed glass just came out of the steam sanitizer and couldn’t handle in instant contraction of a cargo of ice water. Same thing with the egg shells…
If you poke a little hole (a push-pin works good) in the fat end of the egg, very few will crack. You’ll see bubbles come out into the water. Also, if you want to peel them, dump the hot water, shake the eggs around in the pot to crack them, then immediately fill the pot with cold water. After they cool some, peel the eggs under the water. They’ll slip right out of their shells. Magic!
I am the egg man. 
Peace,
mangeorge
According to my handy Cooking for Dummies (p. 173),
It then gives, on p. 174, the steps to do it. I’ve been following this method now for a year and have yet to get a cracked egg. Back when I boiled the eggs, I always got cracked shells.
You can’t soft boil eggs using that method, though. Your timing goes all out of whack.
Mangeorge has it right - you equalise the pressure by putting a tiny pinhole in the round (non-pointed) end of the egg, where the air-sac is. It prevents cracking 99% of the time.
The salt thing is not to prevent cracking, it instead causes less leakage after a crack. That’s what I was told, though it may be an Old Wives’ Tale… Worth a try, it might be just as good, in the long run, for hard boiled eggs.
Soft boiling eggs is easy –
Bring the water to a boil and then remove the pan from the heat. Ease the (not cold!) eggs into the pot and cover. Let it sit for eight minutes (remember, off the burner) and you have perfect soft-boiled eggs.
Monty’s cookbook, Cooking for Dummies is an excellent recommendation. It’s full of good tips, and a good first cookbook for anyone who doesn’t cook, but needs to. Simple, basic stuff.
Peace,
mangeorge
Bah. I have the perfect method for cooking eggs to any degree of doneness you desire, and it’s very easy. No one ever believes me though.
Get an Eggsact Eggtimer. It’s a plastic hemiegg that you put in the water with the eggs. It changes color at the same rate that the eggs cook, with a graded scale to tell you how done they are. Fill the pot with cold water, place the eggs (gently) and the timer in the pot, bring to a low boil, and cook until done. The timer looks totally stupid and 70s, but it really does work.
Cracking is caused by rapid and uneven temperature change, or by being jostled around too violently at a high boil.
Sounds interesting, sturmhauke. The thing has the graded scale on it for us colourblind folks?
You can’t try and test a theory by assuming it’s true and searching for an explanation when your observations don’t fit to it. Question that hearsay theory instead.
Only if you call a tiny fraction of a degree a ‘change’. A different altitude or air pressure affect the temperature more than any sane amount of salt in the water. Or even just put a lid on the pot.
Here are some threads about cooking with salt water:
How does salt stop egg shells from cracking when you are boiling eggs?
Salt in boiling water
salt and boiling water
Seems to me that in cooking threads, for every scientific explanation actually basing on a lot of research work, expert knowledge, experiments, and reasoning, there pop up ten “I’ve heard”, “could it be that”, “works for me but don’t know why”, “never worked for me but why shouldn’t it for you”, “if it works this way there why not here” … not easy to sort out the real information.
It’s a good thing that cooking folks like to share and repeat recipes, that’s how it works best. But it also makes them prone to just share and repeat old wives’ tales about cooking science.
Excuse me if I sneak out of this thread. I don’t even eat eggs. 
The best method is to place the eggs in cold water (temperature of eggs doesn’t matter) and bring to a boil. Remove from heat and let sit in the water for 20 (twenty) minutes. Remove from water. They will be perfectly done, and no cracks.
Here’s a picture of the Eggsact Eggtimer. I think I got mine at Target, but I can’t remember.
Bring your water to boil in the pan as usual. Have your eggs ready. But, when the water boils get a box of matches - yes - matches. Strike a match, and put the lighted match into your boiling water so it sizzles and goes out. Do this with a second match. Now put your eggs in one at a time. They won’t crack. I’ve been using this wierd method for a couple years now and no eggs have cracked. I heard it on a phone-in and tried it. It works every time. 
That, cold shell hitting boiling water.
Just let the eggs warm up first.
I don’t put eggs in the refrigerator, they go in a bowl on the counter, but i don’t know if you can do that with store bought eggs?
After 15 years the zombie’s awakened for a weird old trick that’s perhaps BS.
