# Is leaving eggs out of the fridge, prior to cooking them a direct cause as to how shell break?

I have friend who went to culinary school who claims that cold eggs crack cleaner than eggs at room temperature. Do egg shells crack cleaner coming cold out of the fridge?

Does warming up to room temperature for a few minutes cause the eggs to crack less clean?

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Assuming your fridge temperature is around 4 C (39 F) and your room temperature is 22 C (72 F) then that's a difference of 18 C or 33 F. The two temperatures are not particularly polar so why should it crack differently to when it comes straight from the fridge? It won't be like if you threw hot water onto a frozen window where it would crack, the 2 temperatures here are a lot more polar, 1 below freezing point and 1 near boiling point.

The change in temperature would be fairly gradually (I don't have any Scientific evidence for this but I know from experience as when I take an egg out of the freezer and wait for it to reach room temperature -for culinary purposes- it takes around 45 minutes).

Also on a chemical level, an egg shell being mainly calcium carbonate there is no reason for such a gradual change in temperature to weaken its structure especially as it is in the form of a very stable and strong shape. So no is the answer, I don't think it makes any difference in the weakness of an egg or how it cracks!

Hope this helps!

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I think the question is not whether they crack spontaneously but whether the temperature effects the shape of the crack. – Sobachatina Jan 31 '12 at 20:34
@Sobachatina Have I written that? I think what I was trying to convey how a change in temperature gives no different effect on the cracking of eggs. – Sebiddychef Jan 31 '12 at 20:50
@Sebiddychef- you wrote "The two temperatures are not particularly polar so why should it crack?" It sounds like you are referring to thermal shock. If I misunderstood then I apologize and remove the downvote. – Sobachatina Jan 31 '12 at 21:01
@Sobachatina I can see how that could come across I shall edit the question. – Sebiddychef Jan 31 '12 at 21:06

Aside from technique (always on a flat surface, never on a knife or bowl edge) the age and temperature affect the cracking due to moisture and elasticity.

As eggs age the membrane separates from the shell which leads to smaller bits being able to fall away.

An egg which is fully at room temp, which is more than a few minutes, will have more elasticity to its membrane. This will worsen shell chip loss for older eggs. For decently fresh eggs it will not matter.

Bottom line if your eggs are fresh and you crack correctly temp does not matter.

Incidentally if your eggs have a flat spot when hard boiled they are quite old or have been stored improperly.

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