MadSci Network: Environment |
In the US, eggs are typically run through a hot water shower/pasteurization process. This is essentially to reduce the number of pathogenic microorganisms on the surface of the shell.
During this process, the inner membrane of the egg just under the shell is heated slightly and goes through a sort of "cooking" process. The membrane hardens a little, kind of like the film you get on the top of instant pudding, and pulls away slightly from the shell. Freshly layed eggs don't go through this process so the membrane doesn't harden and sticks to the inside shell making it more difficult to peel than a storebought egg.
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